start refactoring to draw parsed text to an intermediary data structure

13 files changed, 1102 insertions, 800 deletions

diff --git a/Makefile b/Makefile
index 866ed58..5b3933e 100644
--- a/Makefile
+++ b/Makefile
@@ -5,6 +5,7 @@ OBJ      = $(BUILD)runes.o \
 	   $(BUILD)display.o \
 	   $(BUILD)term.o \
 	   $(BUILD)parser.o \
+	   $(BUILD)screen.o \
 	   $(BUILD)config.o \
 	   $(BUILD)window-xlib.o \
 	   $(BUILD)pty-unix.o
@@ -27,9 +28,14 @@ $(BUILD)%.o: $(SRC)%.c
 	@$(MAKEDEPEND) -o $(<:$(SRC)%.c=$(BUILD).%.d) $<
 	$(CC) $(ALLCFLAGS) -c -o $@ $<
 
+$(SRC)screen.c: $(SRC)parser.h
+
 $(SRC)%.c: $(SRC)%.l
 	$(LEX) -o $@ $<
 
+$(SRC)%.h: $(SRC)%.l
+	$(LEX) --header-file=$(<:.l=.h) -o /dev/null $<
+
 clean:
 	rm -f $(OUT) $(OBJ) $(OBJ:$(BUILD)%.o=$(BUILD).%.d)
 	@rmdir -p $(BUILD) > /dev/null 2>&1
diff --git a/src/display.c b/src/display.c
index dc2b00f..b0d380a 100644
--- a/src/display.c
+++ b/src/display.c
@@ -3,24 +3,20 @@
 
 #include "runes.h"
 
-static cairo_pattern_t *runes_display_get_fgcolor(RunesTerm *t);
-static cairo_pattern_t *runes_display_get_bgcolor(RunesTerm *t);
 static void runes_display_recalculate_font_metrics(RunesTerm *t);
-static void runes_display_position_cursor(RunesTerm *t, cairo_t *cr);
+static void runes_display_draw_cell(RunesTerm *t, int row, int col);
 static void runes_display_paint_rectangle(
     RunesTerm *t, cairo_t *cr, cairo_pattern_t *pattern,
-    int x, int y, int width, int height);
-static void runes_display_scroll_up(RunesTerm *t, int rows);
-static void runes_display_scroll_down(RunesTerm *t, int rows);
+    int row, int col, int width, int height);
+static void runes_display_draw_glyph(
+    RunesTerm *t, cairo_t *cr, cairo_pattern_t *pattern, char *buf, size_t len,
+    int row, int col);
 
 void runes_display_init(RunesTerm *t)
 {
     runes_display_recalculate_font_metrics(t);
 
     t->cursorcolor = cairo_pattern_create_rgba(0.0, 1.0, 0.0, 0.5);
-
-    t->fgcolor = -1;
-    t->bgcolor = -1;
 }
 
 void runes_display_set_window_size(RunesTerm *t)
@@ -38,11 +34,11 @@ void runes_display_set_window_size(RunesTerm *t)
     t->xpixel = width;
     t->ypixel = height;
 
-    t->rows = t->ypixel / t->fonty;
-    t->cols = t->xpixel / t->fontx;
+    t->scr.max.row = t->ypixel / t->fonty;
+    t->scr.max.col = t->xpixel / t->fontx;
 
-    t->scroll_top = 0;
-    t->scroll_bottom = t->rows - 1;
+    t->scr.scroll_top    = 0;
+    t->scr.scroll_bottom = t->scr.max.row - 1;
 
     old_cr = t->cr;
 
@@ -55,7 +51,6 @@ void runes_display_set_window_size(RunesTerm *t)
         CAIRO_FORMAT_RGB24, t->xpixel, t->ypixel);
     t->cr = cairo_create(surface);
     cairo_surface_destroy(surface);
-    cairo_set_source(t->cr, runes_display_get_fgcolor(t));
     if (t->layout) {
         pango_cairo_update_layout(t->cr, t->layout);
     }
@@ -92,428 +87,19 @@ void runes_display_set_window_size(RunesTerm *t)
     }
 
     runes_pty_backend_set_window_size(t);
-    runes_display_position_cursor(t, t->cr);
-}
-
-void runes_display_focus_in(RunesTerm *t)
-{
-    t->unfocused = 0;
-}
-
-void runes_display_focus_out(RunesTerm *t)
-{
-    t->unfocused = 1;
-}
-
-void runes_display_move_to(RunesTerm *t, int row, int col)
-{
-    t->row = row;
-    t->col = col;
-
-    if (row > t->scroll_bottom) {
-        runes_display_scroll_down(t, row - t->scroll_bottom);
-        t->row = t->scroll_bottom;
-    }
-    else if (row < t->scroll_top) {
-        runes_display_scroll_up(t, t->scroll_top - row);
-        t->row = t->scroll_top;
-    }
-
-    runes_display_position_cursor(t, t->cr);
 }
 
-void runes_display_show_string_ascii(RunesTerm *t, char *buf, size_t len)
+void runes_display_draw_screen(RunesTerm *t)
 {
-    if (len) {
-        int remaining = len, space_in_row = t->cols - t->col;
-
-        do {
-            int to_write = remaining > space_in_row ? space_in_row : remaining;
-
-            runes_display_paint_rectangle(
-                t, t->cr, runes_display_get_bgcolor(t),
-                t->col, t->row, to_write, 1);
-
-            pango_layout_set_text(t->layout, buf, to_write);
-            pango_cairo_update_layout(t->cr, t->layout);
-            pango_cairo_show_layout(t->cr, t->layout);
-
-            buf += to_write;
-            remaining -= to_write;
-            space_in_row = t->cols;
-            if (remaining) {
-                runes_display_move_to(t, t->row + 1, 0);
-            }
-            else {
-                t->col += len;
-                runes_display_position_cursor(t, t->cr);
-            }
-        } while (remaining > 0);
-    }
-}
+    int r, c;
 
-/* XXX this is gross and kind of slow, but i can't find a better way to do it.
- * i need to be able to convert the string into clusters before laying it out,
- * since i'm not going to be using the full layout anyway, but the only way i
- * can see to do that is with pango_get_log_attrs, which only returns character
- * (not byte) offsets, so i have to reparse the utf8 myself once i get the
- * results. not ideal. */
-void runes_display_show_string_utf8(RunesTerm *t, char *buf, size_t len)
-{
-    size_t i, pos, char_len;
-    PangoLogAttr *attrs;
-
-    char_len = g_utf8_strlen(buf, len);
-    attrs = malloc(sizeof(PangoLogAttr) * (char_len + 1));
-    pango_get_log_attrs(buf, len, -1, NULL, attrs, char_len + 1);
-
-    pos = 0;
-    for (i = 1; i < char_len + 1; ++i) {
-        if (attrs[i].is_cursor_position) {
-            char *startpos, *c;
-            size_t cluster_len;
-            char width = 1;
-
-            startpos = g_utf8_offset_to_pointer(buf, pos);
-            cluster_len = g_utf8_offset_to_pointer(buf, i) - startpos;
-
-            for (c = startpos;
-                 (size_t)(c - startpos) < cluster_len;
-                 c = g_utf8_next_char(c)) {
-                if (g_unichar_iswide(g_utf8_get_char(c))) {
-                    width = 2;
-                }
-            }
-
-            runes_display_paint_rectangle(
-                t, t->cr, runes_display_get_bgcolor(t),
-                t->col, t->row, width, 1);
-
-            pango_layout_set_text(t->layout, startpos, cluster_len);
-            pango_cairo_update_layout(t->cr, t->layout);
-            pango_cairo_show_layout(t->cr, t->layout);
-
-            if (t->col + width >= t->cols) {
-                runes_display_move_to(t, t->row + 1, 0);
-            }
-            else {
-                runes_display_move_to(t, t->row, t->col + width);
-            }
-            pos = i;
+    /* XXX quite inefficient */
+    for (r = 0; r < t->scr.max.row; ++r) {
+        for (c = 0; c < t->scr.max.col; ++c) {
+            runes_display_draw_cell(t, r, c);
         }
     }
-
-    free(attrs);
-}
-
-void runes_display_clear_screen(RunesTerm *t)
-{
-    runes_display_paint_rectangle(
-        t, t->cr, t->bgdefault, 0, 0, t->cols, t->rows);
-}
-
-void runes_display_clear_screen_forward(RunesTerm *t)
-{
-    runes_display_kill_line_forward(t);
-    runes_display_paint_rectangle(
-        t, t->cr, t->bgdefault, 0, t->row, t->cols, t->rows - t->row);
-}
-
-void runes_display_kill_line_forward(RunesTerm *t)
-{
-    runes_display_paint_rectangle(
-        t, t->cr, t->bgdefault, t->col, t->row, t->cols - t->col, 1);
-}
-
-void runes_display_kill_line_backward(RunesTerm *t)
-{
-    runes_display_paint_rectangle(
-        t, t->cr, t->bgdefault, 0, t->row, t->col, 1);
-}
-
-void runes_display_insert_lines(RunesTerm *t, int count)
-{
-    cairo_pattern_t *pattern;
-    cairo_matrix_t matrix;
-
-    cairo_save(t->cr);
-    cairo_push_group(t->cr);
-    pattern = cairo_pattern_create_for_surface(cairo_get_target(t->cr));
-    cairo_matrix_init_translate(&matrix, 0.0, -count * t->fonty);
-    cairo_pattern_set_matrix(pattern, &matrix);
-    runes_display_paint_rectangle(
-        t, t->cr, pattern,
-        0, t->row + count, t->cols, t->scroll_bottom + 1 - t->row - count);
-    cairo_pattern_destroy(pattern);
-    cairo_pop_group_to_source(t->cr);
-    cairo_paint(t->cr);
-    runes_display_paint_rectangle(
-        t, t->cr, t->bgdefault, 0, t->row, t->cols, count);
-    cairo_restore(t->cr);
-}
-
-void runes_display_insert_characters(RunesTerm *t, int count)
-{
-    cairo_pattern_t *pattern;
-    cairo_matrix_t matrix;
-
-    cairo_save(t->cr);
-    cairo_push_group(t->cr);
-    pattern = cairo_pattern_create_for_surface(cairo_get_target(t->cr));
-    cairo_matrix_init_translate(&matrix, -count * t->fontx, 0.0);
-    cairo_pattern_set_matrix(pattern, &matrix);
-    runes_display_paint_rectangle(
-        t, t->cr, pattern,
-        t->col + count, t->row, t->cols - t->col - count, 1);
-    cairo_pattern_destroy(pattern);
-    cairo_pop_group_to_source(t->cr);
-    cairo_paint(t->cr);
-    runes_display_paint_rectangle(
-        t, t->cr, t->bgdefault, t->col, t->row, count, 1);
-    cairo_restore(t->cr);
-}
-
-void runes_display_delete_lines(RunesTerm *t, int count)
-{
-    cairo_pattern_t *pattern;
-    cairo_matrix_t matrix;
-
-    cairo_save(t->cr);
-    cairo_push_group(t->cr);
-    pattern = cairo_pattern_create_for_surface(cairo_get_target(t->cr));
-    cairo_matrix_init_translate(&matrix, 0.0, count * t->fonty);
-    cairo_pattern_set_matrix(pattern, &matrix);
-    runes_display_paint_rectangle(
-        t, t->cr, pattern,
-        0, t->row, t->cols, t->scroll_bottom + 1 - t->row - count);
-    cairo_pattern_destroy(pattern);
-    cairo_pop_group_to_source(t->cr);
-    cairo_paint(t->cr);
-    runes_display_paint_rectangle(
-        t, t->cr, t->bgdefault,
-        0, t->scroll_bottom + 1 - count, t->cols, count);
-    cairo_restore(t->cr);
-}
-
-void runes_display_delete_characters(RunesTerm *t, int count)
-{
-    cairo_pattern_t *pattern;
-    cairo_matrix_t matrix;
-
-    cairo_save(t->cr);
-    cairo_push_group(t->cr);
-    pattern = cairo_pattern_create_for_surface(cairo_get_target(t->cr));
-    cairo_matrix_init_translate(&matrix, count * t->fontx, 0.0);
-    cairo_pattern_set_matrix(pattern, &matrix);
-    runes_display_paint_rectangle(
-        t, t->cr, pattern, t->col, t->row, t->cols - t->col - count, 1);
-    cairo_pattern_destroy(pattern);
-    cairo_pop_group_to_source(t->cr);
-    cairo_paint(t->cr);
-    runes_display_paint_rectangle(
-        t, t->cr, t->bgdefault, t->cols - count, t->row, count, 1);
-    cairo_restore(t->cr);
-}
-
-void runes_display_reset_text_attributes(RunesTerm *t)
-{
-    runes_display_reset_fg_color(t);
-    runes_display_reset_bg_color(t);
-    runes_display_reset_bold(t);
-    runes_display_reset_italic(t);
-    runes_display_reset_underline(t);
-    runes_display_reset_inverse(t);
-}
-
-void runes_display_set_bold(RunesTerm *t)
-{
-    PangoAttrList *attrs;
-
-    attrs = pango_layout_get_attributes(t->layout);
-    if (t->bold_is_bold) {
-        pango_attr_list_change(
-            attrs, pango_attr_weight_new(PANGO_WEIGHT_BOLD));
-    }
-    t->bold = 1;
-    cairo_set_source(t->cr, runes_display_get_fgcolor(t));
-}
-
-void runes_display_reset_bold(RunesTerm *t)
-{
-    PangoAttrList *attrs;
-
-    attrs = pango_layout_get_attributes(t->layout);
-    if (t->bold_is_bold) {
-        pango_attr_list_change(
-            attrs, pango_attr_weight_new(PANGO_WEIGHT_NORMAL));
-    }
-    t->bold = 0;
-    cairo_set_source(t->cr, runes_display_get_fgcolor(t));
-}
-
-void runes_display_set_italic(RunesTerm *t)
-{
-    PangoAttrList *attrs;
-
-    attrs = pango_layout_get_attributes(t->layout);
-    pango_attr_list_change(attrs, pango_attr_style_new(PANGO_STYLE_ITALIC));
-}
-
-void runes_display_reset_italic(RunesTerm *t)
-{
-    PangoAttrList *attrs;
-
-    attrs = pango_layout_get_attributes(t->layout);
-    pango_attr_list_change(attrs, pango_attr_style_new(PANGO_STYLE_NORMAL));
-}
-
-void runes_display_set_underline(RunesTerm *t)
-{
-    PangoAttrList *attrs;
-
-    attrs = pango_layout_get_attributes(t->layout);
-    pango_attr_list_change(
-        attrs, pango_attr_underline_new(PANGO_UNDERLINE_SINGLE));
-}
-
-void runes_display_reset_underline(RunesTerm *t)
-{
-    PangoAttrList *attrs;
-
-    attrs = pango_layout_get_attributes(t->layout);
-    pango_attr_list_change(
-        attrs, pango_attr_underline_new(PANGO_UNDERLINE_NONE));
-}
-
-void runes_display_set_inverse(RunesTerm *t)
-{
-    t->inverse = 1;
-    cairo_set_source(t->cr, runes_display_get_fgcolor(t));
-}
-
-void runes_display_reset_inverse(RunesTerm *t)
-{
-    t->inverse = 0;
-    cairo_set_source(t->cr, runes_display_get_fgcolor(t));
-}
-
-void runes_display_set_fg_color(RunesTerm *t, int color)
-{
-    t->fgcolor = color;
-    cairo_set_source(t->cr, runes_display_get_fgcolor(t));
-}
-
-void runes_display_set_fg_color_rgb(RunesTerm *t, int r, int g, int b)
-{
-    t->fgcolor = -2;
-    if (t->fgcustom) {
-        cairo_pattern_destroy(t->fgcustom);
-    }
-    t->fgcustom = cairo_pattern_create_rgb(
-        (double)r / 255.0, (double)g / 255.0, (double)b / 255.0);
-    cairo_set_source(t->cr, runes_display_get_fgcolor(t));
-}
-
-void runes_display_reset_fg_color(RunesTerm *t)
-{
-    runes_display_set_fg_color(t, -1);
-}
-
-void runes_display_set_bg_color(RunesTerm *t, int color)
-{
-    t->bgcolor = color;
-    cairo_set_source(t->cr, runes_display_get_fgcolor(t));
-}
-
-void runes_display_set_bg_color_rgb(RunesTerm *t, int r, int g, int b)
-{
-    t->bgcolor = -2;
-    if (t->bgcustom) {
-        cairo_pattern_destroy(t->bgcustom);
-    }
-    t->bgcustom = cairo_pattern_create_rgb(
-        (double)r / 255.0, (double)g / 255.0, (double)b / 255.0);
-    cairo_set_source(t->cr, runes_display_get_fgcolor(t));
-}
-
-void runes_display_reset_bg_color(RunesTerm *t)
-{
-    runes_display_set_bg_color(t, -1);
-}
-
-void runes_display_show_cursor(RunesTerm *t)
-{
-    t->hide_cursor = 0;
-}
-
-void runes_display_hide_cursor(RunesTerm *t)
-{
-    t->hide_cursor = 1;
-}
-
-void runes_display_save_cursor(RunesTerm *t)
-{
-    t->saved_row = t->row;
-    t->saved_col = t->col;
-    /* XXX do other stuff here? */
-}
-
-void runes_display_restore_cursor(RunesTerm *t)
-{
-    t->row = t->saved_row;
-    t->col = t->saved_col;
-}
-
-void runes_display_use_alternate_buffer(RunesTerm *t)
-{
-    if (t->alternate_cr) {
-        return;
-    }
-
-    runes_display_save_cursor(t);
-    t->alternate_cr = t->cr;
-    t->cr = NULL;
-    t->xpixel = -1;
-    t->ypixel = -1;
-    runes_display_set_window_size(t);
-}
-
-void runes_display_use_normal_buffer(RunesTerm *t)
-{
-    if (!t->alternate_cr) {
-        return;
-    }
-
-    runes_display_restore_cursor(t);
-    cairo_destroy(t->cr);
-    t->cr = t->alternate_cr;
-    t->alternate_cr = NULL;
-    t->xpixel = -1;
-    t->ypixel = -1;
-    runes_display_set_window_size(t);
-}
-
-void runes_display_set_scroll_region(
-    RunesTerm *t, int top, int bottom, int left, int right)
-{
-    top    = top    < 0           ? 0           : top;
-    bottom = bottom > t->rows - 1 ? t->rows - 1 : bottom;
-    left   = left   < 0           ? 0           : left;
-    right  = right  > t->cols - 1 ? t->cols - 1 : right;
-
-    if (left != 0 || right != t->cols - 1) {
-        fprintf(stderr, "vertical scroll regions not yet supported\n");
-    }
-
-    if (top >= bottom || left >= right) {
-        t->scroll_top = 0;
-        t->scroll_bottom = t->rows - 1;
-        return;
-    }
-
-    t->scroll_top    = top;
-    t->scroll_bottom = bottom;
-    runes_display_move_to(t, t->scroll_top, 0);
+    runes_window_backend_request_flush(t);
 }
 
 void runes_display_cleanup(RunesTerm *t)
@@ -529,45 +115,6 @@ void runes_display_cleanup(RunesTerm *t)
     cairo_destroy(t->cr);
 }
 
-static cairo_pattern_t *runes_display_get_fgcolor(RunesTerm *t)
-{
-    int color = t->inverse ? t->bgcolor : t->fgcolor;
-
-    if (t->inverse && t->bgcolor == t->fgcolor) {
-        return t->bgdefault;
-    }
-    else if (color == -2) {
-        return t->inverse ? t->bgcustom : t->fgcustom;
-    }
-    else if (color == -1) {
-        return t->inverse ? t->bgdefault : t->fgdefault;
-    }
-    else if (t->bold_is_bright && t->bold && color < 8) {
-        return t->colors[color + 8];
-    }
-    else {
-        return t->colors[color];
-    }
-}
-
-static cairo_pattern_t *runes_display_get_bgcolor(RunesTerm *t)
-{
-    int color = t->inverse ? t->fgcolor : t->bgcolor;
-
-    if (t->inverse && t->bgcolor == t->fgcolor) {
-        return t->fgdefault;
-    }
-    else if (color == -2) {
-        return t->inverse ? t->bgcustom : t->fgcustom;
-    }
-    else if (color == -1) {
-        return t->inverse ? t->fgdefault : t->bgdefault;
-    }
-    else {
-        return t->colors[color];
-    }
-}
-
 static void runes_display_recalculate_font_metrics(RunesTerm *t)
 {
     PangoFontDescription *desc;
@@ -601,63 +148,69 @@ static void runes_display_recalculate_font_metrics(RunesTerm *t)
     }
 }
 
-static void runes_display_position_cursor(RunesTerm *t, cairo_t *cr)
+static void runes_display_draw_cell(RunesTerm *t, int row, int col)
 {
-    cairo_move_to(cr, t->col * t->fontx, t->row * t->fonty);
+    struct runes_cell *cell = &t->scr.rows[row].cells[col];
+    cairo_pattern_t *bg = NULL, *fg = NULL;
+
+    switch (cell->bgcolor.type) {
+    case RUNES_COLOR_DEFAULT:
+        bg = t->bgdefault;
+        break;
+    case RUNES_COLOR_IDX:
+        bg = t->colors[cell->bgcolor.idx];
+        break;
+    case RUNES_COLOR_RGB:
+        /* XXX */
+        fprintf(stderr, "rgb colors nyi\n");
+        break;
+    }
+
+    switch (cell->fgcolor.type) {
+    case RUNES_COLOR_DEFAULT:
+        fg = t->fgdefault;
+        break;
+    case RUNES_COLOR_IDX:
+        fg = t->colors[cell->fgcolor.idx];
+        break;
+    case RUNES_COLOR_RGB:
+        /* XXX */
+        fprintf(stderr, "rgb colors nyi\n");
+        break;
+    }
+
+    if (bg) {
+        runes_display_paint_rectangle(t, t->cr, bg, row, col, 1, 1);
+    }
+
+    if (cell->len) {
+        runes_display_draw_glyph(
+            t, t->cr, fg, cell->contents, cell->len, row, col);
+    }
 }
 
 static void runes_display_paint_rectangle(
     RunesTerm *t, cairo_t *cr, cairo_pattern_t *pattern,
-    int x, int y, int width, int height)
+    int row, int col, int width, int height)
 {
     cairo_save(cr);
     cairo_set_source(cr, pattern);
     cairo_rectangle(
-        cr, x * t->fontx, y * t->fonty, width * t->fontx, height * t->fonty);
+        cr, col * t->fontx, row * t->fonty,
+        width * t->fontx, height * t->fonty);
     cairo_fill(cr);
     cairo_restore(cr);
-    runes_display_position_cursor(t, t->cr);
-}
-
-static void runes_display_scroll_up(RunesTerm *t, int rows)
-{
-    cairo_pattern_t *pattern;
-    cairo_matrix_t matrix;
-
-    cairo_save(t->cr);
-    cairo_push_group(t->cr);
-    pattern = cairo_pattern_create_for_surface(cairo_get_target(t->cr));
-    cairo_matrix_init_translate(&matrix, 0.0, -rows * t->fonty);
-    cairo_pattern_set_matrix(pattern, &matrix);
-    runes_display_paint_rectangle(
-        t, t->cr, pattern,
-        0, t->scroll_top + rows,
-        t->cols, t->scroll_bottom - t->scroll_top + 1 - rows);
-    cairo_pattern_destroy(pattern);
-    cairo_pop_group_to_source(t->cr);
-    cairo_paint(t->cr);
-    runes_display_paint_rectangle(
-        t, t->cr, t->bgdefault, 0, t->scroll_top, t->cols, rows);
-    cairo_restore(t->cr);
 }
 
-static void runes_display_scroll_down(RunesTerm *t, int rows)
+static void runes_display_draw_glyph(
+    RunesTerm *t, cairo_t *cr, cairo_pattern_t *pattern, char *buf, size_t len,
+    int row, int col)
 {
-    cairo_pattern_t *pattern;
-    cairo_matrix_t matrix;
-
-    cairo_save(t->cr);
-    cairo_push_group(t->cr);
-    pattern = cairo_pattern_create_for_surface(cairo_get_target(t->cr));
-    cairo_matrix_init_translate(&matrix, 0.0, rows * t->fonty);
-    cairo_pattern_set_matrix(pattern, &matrix);
-    runes_display_paint_rectangle(
-        t, t->cr, pattern,
-        0, t->scroll_top, t->cols, t->scroll_bottom - t->scroll_top);
-    cairo_pattern_destroy(pattern);
-    cairo_pop_group_to_source(t->cr);
-    cairo_paint(t->cr);
-    runes_display_paint_rectangle(
-        t, t->cr, t->bgdefault, 0, t->scroll_bottom + 1 - rows, t->cols, rows);
-    cairo_restore(t->cr);
+    cairo_save(cr);
+    cairo_move_to(cr, col * t->fontx, row * t->fonty);
+    cairo_set_source(cr, pattern);
+    pango_layout_set_text(t->layout, buf, len);
+    pango_cairo_update_layout(t->cr, t->layout);
+    pango_cairo_show_layout(t->cr, t->layout);
+    cairo_restore(cr);
 }
diff --git a/src/display.h b/src/display.h
index 74f3713..d1a895b 100644
--- a/src/display.h
+++ b/src/display.h
@@ -3,42 +3,7 @@
 
 void runes_display_init(RunesTerm *t);
 void runes_display_set_window_size(RunesTerm *t);
-void runes_display_focus_in(RunesTerm *t);
-void runes_display_focus_out(RunesTerm *t);
-void runes_display_move_to(RunesTerm *t, int row, int col);
-void runes_display_show_string_ascii(RunesTerm *t, char *buf, size_t len);
-void runes_display_show_string_utf8(RunesTerm *t, char *buf, size_t len);
-void runes_display_clear_screen(RunesTerm *t);
-void runes_display_clear_screen_forward(RunesTerm *t);
-void runes_display_kill_line_forward(RunesTerm *t);
-void runes_display_kill_line_backward(RunesTerm *t);
-void runes_display_insert_lines(RunesTerm *t, int count);
-void runes_display_insert_characters(RunesTerm *t, int count);
-void runes_display_delete_lines(RunesTerm *t, int count);
-void runes_display_delete_characters(RunesTerm *t, int count);
-void runes_display_reset_text_attributes(RunesTerm *t);
-void runes_display_set_bold(RunesTerm *t);
-void runes_display_reset_bold(RunesTerm *t);
-void runes_display_set_italic(RunesTerm *t);
-void runes_display_reset_italic(RunesTerm *t);
-void runes_display_set_underline(RunesTerm *t);
-void runes_display_reset_underline(RunesTerm *t);
-void runes_display_set_inverse(RunesTerm *t);
-void runes_display_reset_inverse(RunesTerm *t);
-void runes_display_set_fg_color(RunesTerm *t, int color);
-void runes_display_set_fg_color_rgb(RunesTerm *t, int r, int g, int b);
-void runes_display_reset_fg_color(RunesTerm *t);
-void runes_display_set_bg_color(RunesTerm *t, int color);
-void runes_display_set_bg_color_rgb(RunesTerm *t, int r, int g, int b);
-void runes_display_reset_bg_color(RunesTerm *t);
-void runes_display_show_cursor(RunesTerm *t);
-void runes_display_hide_cursor(RunesTerm *t);
-void runes_display_save_cursor(RunesTerm *t);
-void runes_display_restore_cursor(RunesTerm *t);
-void runes_display_use_alternate_buffer(RunesTerm *t);
-void runes_display_use_normal_buffer(RunesTerm *t);
-void runes_display_set_scroll_region(
-    RunesTerm *t, int top, int bottom, int left, int right);
+void runes_display_draw_screen(RunesTerm *t);
 void runes_display_cleanup(RunesTerm *t);
 
 #endif
diff --git a/src/parser.c b/src/parser.c
index 8651128..b9978a0 100644
--- a/src/parser.c
+++ b/src/parser.c
@@ -2361,99 +2361,80 @@ static int yy_flex_strlen (yyconst char * s , yyscan_t yyscanner)
 
 
 
-void runes_parser_process_string(RunesTerm *t, char *buf, size_t len)
-{
-    YY_BUFFER_STATE state;
-    yyscan_t scanner;
-    int remaining;
-
-    /* XXX this will break if buf ends with a partial escape sequence or utf8
-     * character. we need to detect that and not consume the entire input in
-     * that case */
-    runes_parser_yylex_init_extra(t,&scanner);
-    state = runes_parser_yy_scan_bytes(buf, len, scanner);
-    while ((remaining = runes_parser_yylex(scanner)) == -1);
-    t->remaininglen = remaining;
-    if (t->remaininglen) {
-        memmove(t->readbuf, &buf[len - t->remaininglen], t->remaininglen);
-    }
-    runes_parser_yy_delete_buffer(state, scanner);
-    runes_parser_yylex_destroy(scanner);
-}
-
 static void runes_parser_handle_bel(RunesTerm *t)
 {
     if (t->audible_bell) {
-        runes_window_backend_request_audible_bell(t);
+        runes_screen_audible_bell(t);
     }
     else {
-        runes_window_backend_request_visual_bell(t);
+        runes_screen_visual_bell(t);
     }
 }
 
 static void runes_parser_handle_bs(RunesTerm *t)
 {
-    runes_display_move_to(t, t->row, t->col - 1);
+    runes_screen_move_to(t, t->scr.cur.row, t->scr.cur.col - 1);
 }
 
 static void runes_parser_handle_tab(RunesTerm *t)
 {
-    runes_display_move_to(t, t->row, t->col - (t->col % 8) + 8);
+    runes_screen_move_to(
+        t, t->scr.cur.row, t->scr.cur.col - (t->scr.cur.col % 8) + 8);
 }
 
 static void runes_parser_handle_lf(RunesTerm *t)
 {
-    runes_display_move_to(t, t->row + 1, t->col);
+    runes_screen_move_to(t, t->scr.cur.row + 1, t->scr.cur.col);
 }
 
 static void runes_parser_handle_cr(RunesTerm *t)
 {
-    runes_display_move_to(t, t->row, 0);
+    runes_screen_move_to(t, t->scr.cur.row, 0);
 }
 
 static void runes_parser_handle_deckpam(RunesTerm *t)
 {
-    t->application_keypad = 1;
+    runes_screen_set_application_keypad(t);
 }
 
 static void runes_parser_handle_deckpnm(RunesTerm *t)
 {
-    t->application_keypad = 0;
+    runes_screen_reset_application_keypad(t);
 }
 
 static void runes_parser_handle_ri(RunesTerm *t)
 {
-    runes_display_move_to(t, t->row - 1, t->col);
+    runes_screen_move_to(t, t->scr.cur.row - 1, t->scr.cur.col);
 }
 
 static void runes_parser_handle_ris(RunesTerm *t)
 {
-    runes_display_use_normal_buffer(t);
-    runes_display_set_scroll_region(t, 0, t->rows - 1, 0, t->cols - 1);
-    runes_display_clear_screen(t);
-    runes_display_save_cursor(t);
-    runes_display_reset_text_attributes(t);
-    runes_display_show_cursor(t);
-
-    t->application_keypad            = 0;
-    t->application_cursor            = 0;
-    t->mouse_reporting_press         = 0;
-    t->mouse_reporting_press_release = 0;
+    runes_screen_use_normal_buffer(t);
+    runes_screen_set_scroll_region(
+        t, 0, t->scr.max.row - 1, 0, t->scr.max.col - 1);
+    runes_screen_clear_screen(t);
+    runes_screen_save_cursor(t);
+    runes_screen_reset_text_attributes(t);
+    runes_screen_show_cursor(t);
+    runes_screen_reset_application_keypad(t);
+    runes_screen_reset_application_cursor(t);
+    runes_screen_reset_mouse_reporting_press(t);
+    runes_screen_reset_mouse_reporting_press_release(t);
 }
 
 static void runes_parser_handle_vb(RunesTerm *t)
 {
-    runes_window_backend_request_visual_bell(t);
+    runes_screen_visual_bell(t);
 }
 
 static void runes_parser_handle_decsc(RunesTerm *t)
 {
-    runes_display_save_cursor(t);
+    runes_screen_save_cursor(t);
 }
 
 static void runes_parser_handle_decrc(RunesTerm *t)
 {
-    runes_display_restore_cursor(t);
+    runes_screen_restore_cursor(t);
 }
 
 static void runes_parser_extract_csi_params(
@@ -2506,7 +2487,7 @@ static void runes_parser_handle_ich(RunesTerm *t, char *buf, size_t len)
     int params[RUNES_PARSER_CSI_MAX_PARAMS] = { 1 }, nparams;
 
     runes_parser_extract_csi_params(buf + 2, len - 3, params, &nparams);
-    runes_display_insert_characters(t, params[0]);
+    runes_screen_insert_characters(t, params[0]);
 }
 
 static void runes_parser_handle_cuu(RunesTerm *t, char *buf, size_t len)
@@ -2514,7 +2495,7 @@ static void runes_parser_handle_cuu(RunesTerm *t, char *buf, size_t len)
     int params[RUNES_PARSER_CSI_MAX_PARAMS] = { 1 }, nparams;
 
     runes_parser_extract_csi_params(buf + 2, len - 3, params, &nparams);
-    runes_display_move_to(t, t->row - params[0], t->col);
+    runes_screen_move_to(t, t->scr.cur.row - params[0], t->scr.cur.col);
 }
 
 static void runes_parser_handle_cud(RunesTerm *t, char *buf, size_t len)
@@ -2522,7 +2503,7 @@ static void runes_parser_handle_cud(RunesTerm *t, char *buf, size_t len)
     int params[RUNES_PARSER_CSI_MAX_PARAMS] = { 1 }, nparams;
 
     runes_parser_extract_csi_params(buf + 2, len - 3, params, &nparams);
-    runes_display_move_to(t, t->row + params[0], t->col);
+    runes_screen_move_to(t, t->scr.cur.row + params[0], t->scr.cur.col);
 }
 
 static void runes_parser_handle_cuf(RunesTerm *t, char *buf, size_t len)
@@ -2530,7 +2511,7 @@ static void runes_parser_handle_cuf(RunesTerm *t, char *buf, size_t len)
     int params[RUNES_PARSER_CSI_MAX_PARAMS] = { 1 }, nparams;
 
     runes_parser_extract_csi_params(buf + 2, len - 3, params, &nparams);
-    runes_display_move_to(t, t->row, t->col + params[0]);
+    runes_screen_move_to(t, t->scr.cur.row, t->scr.cur.col + params[0]);
 }
 
 static void runes_parser_handle_cub(RunesTerm *t, char *buf, size_t len)
@@ -2538,7 +2519,7 @@ static void runes_parser_handle_cub(RunesTerm *t, char *buf, size_t len)
     int params[RUNES_PARSER_CSI_MAX_PARAMS] = { 1 }, nparams;
 
     runes_parser_extract_csi_params(buf + 2, len - 3, params, &nparams);
-    runes_display_move_to(t, t->row, t->col - params[0]);
+    runes_screen_move_to(t, t->scr.cur.row, t->scr.cur.col - params[0]);
 }
 
 static void runes_parser_handle_cup(RunesTerm *t, char *buf, size_t len)
@@ -2552,7 +2533,7 @@ static void runes_parser_handle_cup(RunesTerm *t, char *buf, size_t len)
     if (params[1] == 0) {
         params[1] = 1;
     }
-    runes_display_move_to(t, params[0] - 1, params[1] - 1);
+    runes_screen_move_to(t, params[0] - 1, params[1] - 1);
 }
 
 static void runes_parser_handle_ed(RunesTerm *t, char *buf, size_t len)
@@ -2562,14 +2543,13 @@ static void runes_parser_handle_ed(RunesTerm *t, char *buf, size_t len)
     runes_parser_extract_csi_params(buf + 2, len - 3, params, &nparams);
     switch (params[0]) {
     case 0:
-        runes_display_clear_screen_forward(t);
+        runes_screen_clear_screen_forward(t);
         break;
     case 1:
-        /* XXX */
-        fprintf(stderr, "unhandled ED parameter 1\n");
+        runes_screen_clear_screen_backward(t);
         break;
     case 2:
-        runes_display_clear_screen(t);
+        runes_screen_clear_screen(t);
         break;
     default:
         fprintf(stderr, "unknown ED parameter %d\n", params[0]);
@@ -2584,14 +2564,13 @@ static void runes_parser_handle_el(RunesTerm *t, char *buf, size_t len)
     runes_parser_extract_csi_params(buf + 2, len - 3, params, &nparams);
     switch (params[0]) {
     case 0:
-        runes_display_kill_line_forward(t);
+        runes_screen_kill_line_forward(t);
         break;
     case 1:
-        runes_display_kill_line_backward(t);
+        runes_screen_kill_line_backward(t);
         break;
     case 2:
-        runes_display_kill_line_forward(t);
-        runes_display_kill_line_backward(t);
+        runes_screen_kill_line(t);
         break;
     default:
         fprintf(stderr, "unknown EL parameter %d\n", params[0]);
@@ -2604,8 +2583,8 @@ static void runes_parser_handle_il(RunesTerm *t, char *buf, size_t len)
     int params[RUNES_PARSER_CSI_MAX_PARAMS] = { 1 }, nparams;
 
     runes_parser_extract_csi_params(buf + 2, len - 3, params, &nparams);
-    runes_display_insert_lines(t, params[0]);
-    runes_display_move_to(t, t->row, 0);
+    runes_screen_insert_lines(t, params[0]);
+    runes_screen_move_to(t, t->scr.cur.row, 0);
 }
 
 static void runes_parser_handle_dl(RunesTerm *t, char *buf, size_t len)
@@ -2613,8 +2592,8 @@ static void runes_parser_handle_dl(RunesTerm *t, char *buf, size_t len)
     int params[RUNES_PARSER_CSI_MAX_PARAMS] = { 1 }, nparams;
 
     runes_parser_extract_csi_params(buf + 2, len - 3, params, &nparams);
-    runes_display_delete_lines(t, params[0]);
-    runes_display_move_to(t, t->row, 0);
+    runes_screen_delete_lines(t, params[0]);
+    runes_screen_move_to(t, t->scr.cur.row, 0);
 }
 
 static void runes_parser_handle_dch(RunesTerm *t, char *buf, size_t len)
@@ -2622,7 +2601,7 @@ static void runes_parser_handle_dch(RunesTerm *t, char *buf, size_t len)
     int params[RUNES_PARSER_CSI_MAX_PARAMS] = { 1 }, nparams;
 
     runes_parser_extract_csi_params(buf + 2, len - 3, params, &nparams);
-    runes_display_delete_characters(t, params[0]);
+    runes_screen_delete_characters(t, params[0]);
 }
 
 static void runes_parser_handle_sm(RunesTerm *t, char *buf, size_t len)
@@ -2648,20 +2627,20 @@ static void runes_parser_handle_sm(RunesTerm *t, char *buf, size_t len)
         case '?':
             switch (params[i]) {
             case 1:
-                t->application_cursor = 1;
+                runes_screen_set_application_cursor(t);
                 break;
             case 9:
-                t->mouse_reporting_press = 1;
+                runes_screen_set_mouse_reporting_press(t);
                 break;
             case 25:
-                runes_display_show_cursor(t);
+                runes_screen_show_cursor(t);
                 break;
             case 1000:
-                t->mouse_reporting_press_release = 1;
+                runes_screen_set_mouse_reporting_press_release(t);
                 break;
             case 47:
             case 1049:
-                runes_display_use_alternate_buffer(t);
+                runes_screen_use_alternate_buffer(t);
                 break;
             default:
                 fprintf(
@@ -2702,20 +2681,20 @@ static void runes_parser_handle_rm(RunesTerm *t, char *buf, size_t len)
         case '?':
             switch (params[i]) {
             case 1:
-                t->application_cursor = 0;
+                runes_screen_set_application_cursor(t);
                 break;
             case 9:
-                t->mouse_reporting_press = 0;
+                runes_screen_set_mouse_reporting_press(t);
                 break;
             case 25:
-                runes_display_hide_cursor(t);
+                runes_screen_hide_cursor(t);
                 break;
             case 1000:
-                t->mouse_reporting_press_release = 0;
+                runes_screen_set_mouse_reporting_press_release(t);
                 break;
             case 47:
             case 1049:
-                runes_display_use_normal_buffer(t);
+                runes_screen_use_normal_buffer(t);
                 break;
             default:
                 fprintf(
@@ -2744,35 +2723,35 @@ static void runes_parser_handle_sgr(RunesTerm *t, char *buf, size_t len)
     for (i = 0; i < nparams; ++i) {
         switch (params[i]) {
         case 0:
-            runes_display_reset_text_attributes(t);
+            runes_screen_reset_text_attributes(t);
             break;
         case 1:
-            runes_display_set_bold(t);
+            runes_screen_set_bold(t);
             break;
         case 3:
-            runes_display_set_italic(t);
+            runes_screen_set_italic(t);
             break;
         case 4:
-            runes_display_set_underline(t);
+            runes_screen_set_underline(t);
             break;
         case 7:
-            runes_display_set_inverse(t);
+            runes_screen_set_inverse(t);
             break;
         case 22:
-            runes_display_reset_bold(t);
+            runes_screen_reset_bold(t);
             break;
         case 23:
-            runes_display_reset_italic(t);
+            runes_screen_reset_italic(t);
             break;
         case 24:
-            runes_display_reset_underline(t);
+            runes_screen_reset_underline(t);
             break;
         case 27:
-            runes_display_reset_inverse(t);
+            runes_screen_reset_inverse(t);
             break;
         case 30: case 31: case 32: case 33:
         case 34: case 35: case 36: case 37:
-            runes_display_set_fg_color(t, params[i] - 30);
+            runes_screen_set_fg_color(t, params[i] - 30);
             break;
         case 38: {
             i++;
@@ -2793,7 +2772,7 @@ static void runes_parser_handle_sgr(RunesTerm *t, char *buf, size_t len)
                         params[i - 4], params[i - 3]);
                     break;
                 }
-                runes_display_set_fg_color_rgb(
+                runes_screen_set_fg_color_rgb(
                     t, params[i - 2], params[i - 1], params[i]);
                 break;
             case 5:
@@ -2805,7 +2784,7 @@ static void runes_parser_handle_sgr(RunesTerm *t, char *buf, size_t len)
                         params[i - 2], params[i - 1]);
                     break;
                 }
-                runes_display_set_fg_color(t, params[i]);
+                runes_screen_set_fg_color(t, params[i]);
                 break;
             default:
                 i++;
@@ -2817,11 +2796,11 @@ static void runes_parser_handle_sgr(RunesTerm *t, char *buf, size_t len)
             break;
         }
         case 39:
-            runes_display_reset_fg_color(t);
+            runes_screen_reset_fg_color(t);
             break;
         case 40: case 41: case 42: case 43:
         case 44: case 45: case 46: case 47:
-            runes_display_set_bg_color(t, params[i] - 40);
+            runes_screen_set_bg_color(t, params[i] - 40);
             break;
         case 48: {
             i++;
@@ -2842,7 +2821,7 @@ static void runes_parser_handle_sgr(RunesTerm *t, char *buf, size_t len)
                         params[i - 4], params[i - 3]);
                     break;
                 }
-                runes_display_set_bg_color_rgb(
+                runes_screen_set_bg_color_rgb(
                     t, params[i - 2], params[i - 1], params[i]);
                 break;
             case 5:
@@ -2854,7 +2833,7 @@ static void runes_parser_handle_sgr(RunesTerm *t, char *buf, size_t len)
                         params[i - 2], params[i - 1]);
                     break;
                 }
-                runes_display_set_bg_color(t, params[i]);
+                runes_screen_set_bg_color(t, params[i]);
                 break;
             default:
                 i++;
@@ -2866,15 +2845,15 @@ static void runes_parser_handle_sgr(RunesTerm *t, char *buf, size_t len)
             break;
         }
         case 49:
-            runes_display_reset_bg_color(t);
+            runes_screen_reset_bg_color(t);
             break;
         case 90: case 91: case 92: case 93:
         case 94: case 95: case 96: case 97:
-            runes_display_set_fg_color(t, params[i] - 82);
+            runes_screen_set_fg_color(t, params[i] - 82);
             break;
         case 100: case 101: case 102: case 103:
         case 104: case 105: case 106: case 107:
-            runes_display_set_bg_color(t, params[i] - 92);
+            runes_screen_set_bg_color(t, params[i] - 92);
             break;
         default:
             fprintf(stderr, "unknown SGR parameter: %d\n", params[i]);
@@ -2885,12 +2864,13 @@ static void runes_parser_handle_sgr(RunesTerm *t, char *buf, size_t len)
 
 static void runes_parser_handle_csr(RunesTerm *t, char *buf, size_t len)
 {
-    int params[RUNES_PARSER_CSI_MAX_PARAMS] = { 1, t->rows, 1, t->cols };
+    int params[RUNES_PARSER_CSI_MAX_PARAMS] = {
+        1, t->scr.max.row, 1, t->scr.max.col };
     int nparams;
 
     runes_parser_extract_csi_params(buf + 2, len - 3, params, &nparams);
 
-    runes_display_set_scroll_region(
+    runes_screen_set_scroll_region(
         t, params[0] - 1, params[1] - 1, params[2] - 1, params[3] - 1);
 }
 
@@ -2902,7 +2882,7 @@ static void runes_parser_handle_decsed(RunesTerm *t, char *buf, size_t len)
     switch (params[0]) {
     case 0:
         /* XXX not quite correct */
-        runes_display_clear_screen_forward(t);
+        runes_screen_clear_screen_forward(t);
         break;
     case 1:
         /* XXX */
@@ -2910,7 +2890,7 @@ static void runes_parser_handle_decsed(RunesTerm *t, char *buf, size_t len)
         break;
     case 2:
         /* XXX not quite correct */
-        runes_display_clear_screen(t);
+        runes_screen_clear_screen(t);
         break;
     default:
         fprintf(stderr, "unknown DECSED parameter %d\n", params[0]);
@@ -2926,7 +2906,7 @@ static void runes_parser_handle_decsel(RunesTerm *t, char *buf, size_t len)
     switch (params[0]) {
     case 0:
         /* XXX not quite correct */
-        runes_display_kill_line_forward(t);
+        runes_screen_kill_line_forward(t);
         break;
     case 1:
         /* XXX */
@@ -2944,28 +2924,28 @@ static void runes_parser_handle_decsel(RunesTerm *t, char *buf, size_t len)
 
 static void runes_parser_handle_osc0(RunesTerm *t, char *buf, size_t len)
 {
-    runes_window_backend_set_icon_name(t, buf + 4, len - 5);
-    runes_window_backend_set_window_title(t, buf + 4, len - 5);
+    runes_screen_set_icon_name(t, buf + 4, len - 5);
+    runes_screen_set_window_title(t, buf + 4, len - 5);
 }
 
 static void runes_parser_handle_osc1(RunesTerm *t, char *buf, size_t len)
 {
-    runes_window_backend_set_icon_name(t, buf + 4, len - 5);
+    runes_screen_set_icon_name(t, buf + 4, len - 5);
 }
 
 static void runes_parser_handle_osc2(RunesTerm *t, char *buf, size_t len)
 {
-    runes_window_backend_set_window_title(t, buf + 4, len - 5);
+    runes_screen_set_window_title(t, buf + 4, len - 5);
 }
 
 static void runes_parser_handle_ascii(RunesTerm *t, char *text, size_t len)
 {
-    runes_display_show_string_ascii(t, text, len);
+    runes_screen_show_string_ascii(t, text, len);
 }
 
 static void runes_parser_handle_text(RunesTerm *t, char *text, size_t len)
 {
-    runes_display_show_string_utf8(t, text, len);
+    runes_screen_show_string_utf8(t, text, len);
 }
 
 /* XXX these are copied from the generated file so that I can add the UNUSED
diff --git a/src/parser.h b/src/parser.h
index ea449a8..95a67cd 100644
--- a/src/parser.h
+++ b/src/parser.h
@@ -1,6 +1,338 @@
-#ifndef _RUNES_PARSER_H
-#define _RUNES_PARSER_H
+#ifndef runes_parser_yyHEADER_H
+#define runes_parser_yyHEADER_H 1
+#define runes_parser_yyIN_HEADER 1
 
-void runes_parser_process_string(RunesTerm *t, char *buf, size_t len);
+#line 6 "src/parser.h"
 
+#line 8 "src/parser.h"
+
+#define  YY_INT_ALIGNED short int
+
+/* A lexical scanner generated by flex */
+
+#define FLEX_SCANNER
+#define YY_FLEX_MAJOR_VERSION 2
+#define YY_FLEX_MINOR_VERSION 5
+#define YY_FLEX_SUBMINOR_VERSION 39
+#if YY_FLEX_SUBMINOR_VERSION > 0
+#define FLEX_BETA
+#endif
+
+/* First, we deal with  platform-specific or compiler-specific issues. */
+
+/* begin standard C headers. */
+#include <stdio.h>
+#include <string.h>
+#include <errno.h>
+#include <stdlib.h>
+
+/* end standard C headers. */
+
+/* flex integer type definitions */
+
+#ifndef FLEXINT_H
+#define FLEXINT_H
+
+/* C99 systems have <inttypes.h>. Non-C99 systems may or may not. */
+
+#if defined (__STDC_VERSION__) && __STDC_VERSION__ >= 199901L
+
+/* C99 says to define __STDC_LIMIT_MACROS before including stdint.h,
+ * if you want the limit (max/min) macros for int types. 
+ */
+#ifndef __STDC_LIMIT_MACROS
+#define __STDC_LIMIT_MACROS 1
+#endif
+
+#include <inttypes.h>
+typedef int8_t flex_int8_t;
+typedef uint8_t flex_uint8_t;
+typedef int16_t flex_int16_t;
+typedef uint16_t flex_uint16_t;
+typedef int32_t flex_int32_t;
+typedef uint32_t flex_uint32_t;
+#else
+typedef signed char flex_int8_t;
+typedef short int flex_int16_t;
+typedef int flex_int32_t;
+typedef unsigned char flex_uint8_t; 
+typedef unsigned short int flex_uint16_t;
+typedef unsigned int flex_uint32_t;
+
+/* Limits of integral types. */
+#ifndef INT8_MIN
+#define INT8_MIN               (-128)
+#endif
+#ifndef INT16_MIN
+#define INT16_MIN              (-32767-1)
+#endif
+#ifndef INT32_MIN
+#define INT32_MIN              (-2147483647-1)
+#endif
+#ifndef INT8_MAX
+#define INT8_MAX               (127)
+#endif
+#ifndef INT16_MAX
+#define INT16_MAX              (32767)
+#endif
+#ifndef INT32_MAX
+#define INT32_MAX              (2147483647)
+#endif
+#ifndef UINT8_MAX
+#define UINT8_MAX              (255U)
+#endif
+#ifndef UINT16_MAX
+#define UINT16_MAX             (65535U)
+#endif
+#ifndef UINT32_MAX
+#define UINT32_MAX             (4294967295U)
+#endif
+
+#endif /* ! C99 */
+
+#endif /* ! FLEXINT_H */
+
+#ifdef __cplusplus
+
+/* The "const" storage-class-modifier is valid. */
+#define YY_USE_CONST
+
+#else	/* ! __cplusplus */
+
+/* C99 requires __STDC__ to be defined as 1. */
+#if defined (__STDC__)
+
+#define YY_USE_CONST
+
+#endif	/* defined (__STDC__) */
+#endif	/* ! __cplusplus */
+
+#ifdef YY_USE_CONST
+#define yyconst const
+#else
+#define yyconst
+#endif
+
+/* An opaque pointer. */
+#ifndef YY_TYPEDEF_YY_SCANNER_T
+#define YY_TYPEDEF_YY_SCANNER_T
+typedef void* yyscan_t;
+#endif
+
+/* For convenience, these vars (plus the bison vars far below)
+   are macros in the reentrant scanner. */
+#define yyin yyg->yyin_r
+#define yyout yyg->yyout_r
+#define yyextra yyg->yyextra_r
+#define yyleng yyg->yyleng_r
+#define yytext yyg->yytext_r
+#define yylineno (YY_CURRENT_BUFFER_LVALUE->yy_bs_lineno)
+#define yycolumn (YY_CURRENT_BUFFER_LVALUE->yy_bs_column)
+#define yy_flex_debug yyg->yy_flex_debug_r
+
+/* Size of default input buffer. */
+#ifndef YY_BUF_SIZE
+#define YY_BUF_SIZE 16384
 #endif
+
+#ifndef YY_TYPEDEF_YY_BUFFER_STATE
+#define YY_TYPEDEF_YY_BUFFER_STATE
+typedef struct yy_buffer_state *YY_BUFFER_STATE;
+#endif
+
+#ifndef YY_TYPEDEF_YY_SIZE_T
+#define YY_TYPEDEF_YY_SIZE_T
+typedef size_t yy_size_t;
+#endif
+
+#ifndef YY_STRUCT_YY_BUFFER_STATE
+#define YY_STRUCT_YY_BUFFER_STATE
+struct yy_buffer_state
+	{
+	FILE *yy_input_file;
+
+	char *yy_ch_buf;		/* input buffer */
+	char *yy_buf_pos;		/* current position in input buffer */
+
+	/* Size of input buffer in bytes, not including room for EOB
+	 * characters.
+	 */
+	yy_size_t yy_buf_size;
+
+	/* Number of characters read into yy_ch_buf, not including EOB
+	 * characters.
+	 */
+	yy_size_t yy_n_chars;
+
+	/* Whether we "own" the buffer - i.e., we know we created it,
+	 * and can realloc() it to grow it, and should free() it to
+	 * delete it.
+	 */
+	int yy_is_our_buffer;
+
+	/* Whether this is an "interactive" input source; if so, and
+	 * if we're using stdio for input, then we want to use getc()
+	 * instead of fread(), to make sure we stop fetching input after
+	 * each newline.
+	 */
+	int yy_is_interactive;
+
+	/* Whether we're considered to be at the beginning of a line.
+	 * If so, '^' rules will be active on the next match, otherwise
+	 * not.
+	 */
+	int yy_at_bol;
+
+    int yy_bs_lineno; /**< The line count. */
+    int yy_bs_column; /**< The column count. */
+    
+	/* Whether to try to fill the input buffer when we reach the
+	 * end of it.
+	 */
+	int yy_fill_buffer;
+
+	int yy_buffer_status;
+
+	};
+#endif /* !YY_STRUCT_YY_BUFFER_STATE */
+
+void runes_parser_yyrestart (FILE *input_file ,yyscan_t yyscanner );
+void runes_parser_yy_switch_to_buffer (YY_BUFFER_STATE new_buffer ,yyscan_t yyscanner );
+YY_BUFFER_STATE runes_parser_yy_create_buffer (FILE *file,int size ,yyscan_t yyscanner );
+void runes_parser_yy_delete_buffer (YY_BUFFER_STATE b ,yyscan_t yyscanner );
+void runes_parser_yy_flush_buffer (YY_BUFFER_STATE b ,yyscan_t yyscanner );
+void runes_parser_yypush_buffer_state (YY_BUFFER_STATE new_buffer ,yyscan_t yyscanner );
+void runes_parser_yypop_buffer_state (yyscan_t yyscanner );
+
+YY_BUFFER_STATE runes_parser_yy_scan_buffer (char *base,yy_size_t size ,yyscan_t yyscanner );
+YY_BUFFER_STATE runes_parser_yy_scan_string (yyconst char *yy_str ,yyscan_t yyscanner );
+YY_BUFFER_STATE runes_parser_yy_scan_bytes (yyconst char *bytes,yy_size_t len ,yyscan_t yyscanner );
+
+void *runes_parser_yyalloc (yy_size_t ,yyscan_t yyscanner );
+void *runes_parser_yyrealloc (void *,yy_size_t ,yyscan_t yyscanner );
+void runes_parser_yyfree (void * ,yyscan_t yyscanner );
+
+/* Begin user sect3 */
+
+#define runes_parser_yywrap(yyscanner) 1
+#define YY_SKIP_YYWRAP
+
+#define yytext_ptr yytext_r
+
+#ifdef YY_HEADER_EXPORT_START_CONDITIONS
+#define INITIAL 0
+
+#endif
+
+#ifndef YY_NO_UNISTD_H
+/* Special case for "unistd.h", since it is non-ANSI. We include it way
+ * down here because we want the user's section 1 to have been scanned first.
+ * The user has a chance to override it with an option.
+ */
+#include <unistd.h>
+#endif
+
+#define YY_EXTRA_TYPE RunesTerm *
+
+int runes_parser_yylex_init (yyscan_t* scanner);
+
+int runes_parser_yylex_init_extra (YY_EXTRA_TYPE user_defined,yyscan_t* scanner);
+
+/* Accessor methods to globals.
+   These are made visible to non-reentrant scanners for convenience. */
+
+int runes_parser_yylex_destroy (yyscan_t yyscanner );
+
+int runes_parser_yyget_debug (yyscan_t yyscanner );
+
+void runes_parser_yyset_debug (int debug_flag ,yyscan_t yyscanner );
+
+YY_EXTRA_TYPE runes_parser_yyget_extra (yyscan_t yyscanner );
+
+void runes_parser_yyset_extra (YY_EXTRA_TYPE user_defined ,yyscan_t yyscanner );
+
+FILE *runes_parser_yyget_in (yyscan_t yyscanner );
+
+void runes_parser_yyset_in  (FILE * in_str ,yyscan_t yyscanner );
+
+FILE *runes_parser_yyget_out (yyscan_t yyscanner );
+
+void runes_parser_yyset_out  (FILE * out_str ,yyscan_t yyscanner );
+
+yy_size_t runes_parser_yyget_leng (yyscan_t yyscanner );
+
+char *runes_parser_yyget_text (yyscan_t yyscanner );
+
+int runes_parser_yyget_lineno (yyscan_t yyscanner );
+
+void runes_parser_yyset_lineno (int line_number ,yyscan_t yyscanner );
+
+int runes_parser_yyget_column  (yyscan_t yyscanner );
+
+void runes_parser_yyset_column (int column_no ,yyscan_t yyscanner );
+
+/* Macros after this point can all be overridden by user definitions in
+ * section 1.
+ */
+
+#ifndef YY_SKIP_YYWRAP
+#ifdef __cplusplus
+extern "C" int runes_parser_yywrap (yyscan_t yyscanner );
+#else
+extern int runes_parser_yywrap (yyscan_t yyscanner );
+#endif
+#endif
+
+#ifndef yytext_ptr
+static void yy_flex_strncpy (char *,yyconst char *,int ,yyscan_t yyscanner);
+#endif
+
+#ifdef YY_NEED_STRLEN
+static int yy_flex_strlen (yyconst char * ,yyscan_t yyscanner);
+#endif
+
+#ifndef YY_NO_INPUT
+
+#endif
+
+/* Amount of stuff to slurp up with each read. */
+#ifndef YY_READ_BUF_SIZE
+#define YY_READ_BUF_SIZE 8192
+#endif
+
+/* Number of entries by which start-condition stack grows. */
+#ifndef YY_START_STACK_INCR
+#define YY_START_STACK_INCR 25
+#endif
+
+/* Default declaration of generated scanner - a define so the user can
+ * easily add parameters.
+ */
+#ifndef YY_DECL
+#define YY_DECL_IS_OURS 1
+
+extern int runes_parser_yylex (yyscan_t yyscanner);
+
+#define YY_DECL int runes_parser_yylex (yyscan_t yyscanner)
+#endif /* !YY_DECL */
+
+/* yy_get_previous_state - get the state just before the EOB char was reached */
+
+#undef YY_NEW_FILE
+#undef YY_FLUSH_BUFFER
+#undef yy_set_bol
+#undef yy_new_buffer
+#undef yy_set_interactive
+#undef YY_DO_BEFORE_ACTION
+
+#ifdef YY_DECL_IS_OURS
+#undef YY_DECL_IS_OURS
+#undef YY_DECL
+#endif
+
+#line 232 "src/parser.l"
+
+
+#line 337 "src/parser.h"
+#undef runes_parser_yyIN_HEADER
+#endif /* runes_parser_yyHEADER_H */
diff --git a/src/parser.l b/src/parser.l
index 2a2e94c..f2682c8 100644
--- a/src/parser.l
+++ b/src/parser.l
@@ -231,96 +231,80 @@ static void runes_parser_handle_text(RunesTerm *t, char *text, size_t len);
 
 %%
 
-void runes_parser_process_string(RunesTerm *t, char *buf, size_t len)
-{
-    YY_BUFFER_STATE state;
-    yyscan_t scanner;
-    int remaining;
-
-    yylex_init_extra(t, &scanner);
-    state = runes_parser_yy_scan_bytes(buf, len, scanner);
-    while ((remaining = runes_parser_yylex(scanner)) == -1);
-    t->remaininglen = remaining;
-    if (t->remaininglen) {
-        memmove(t->readbuf, &buf[len - t->remaininglen], t->remaininglen);
-    }
-    runes_parser_yy_delete_buffer(state, scanner);
-    yylex_destroy(scanner);
-}
-
 static void runes_parser_handle_bel(RunesTerm *t)
 {
     if (t->audible_bell) {
-        runes_window_backend_request_audible_bell(t);
+        runes_screen_audible_bell(t);
     }
     else {
-        runes_window_backend_request_visual_bell(t);
+        runes_screen_visual_bell(t);
     }
 }
 
 static void runes_parser_handle_bs(RunesTerm *t)
 {
-    runes_display_move_to(t, t->row, t->col - 1);
+    runes_screen_move_to(t, t->scr.cur.row, t->scr.cur.col - 1);
 }
 
 static void runes_parser_handle_tab(RunesTerm *t)
 {
-    runes_display_move_to(t, t->row, t->col - (t->col % 8) + 8);
+    runes_screen_move_to(
+        t, t->scr.cur.row, t->scr.cur.col - (t->scr.cur.col % 8) + 8);
 }
 
 static void runes_parser_handle_lf(RunesTerm *t)
 {
-    runes_display_move_to(t, t->row + 1, t->col);
+    runes_screen_move_to(t, t->scr.cur.row + 1, t->scr.cur.col);
 }
 
 static void runes_parser_handle_cr(RunesTerm *t)
 {
-    runes_display_move_to(t, t->row, 0);
+    runes_screen_move_to(t, t->scr.cur.row, 0);
 }
 
 static void runes_parser_handle_deckpam(RunesTerm *t)
 {
-    t->application_keypad = 1;
+    runes_screen_set_application_keypad(t);
 }
 
 static void runes_parser_handle_deckpnm(RunesTerm *t)
 {
-    t->application_keypad = 0;
+    runes_screen_reset_application_keypad(t);
 }
 
 static void runes_parser_handle_ri(RunesTerm *t)
 {
-    runes_display_move_to(t, t->row - 1, t->col);
+    runes_screen_move_to(t, t->scr.cur.row - 1, t->scr.cur.col);
 }
 
 static void runes_parser_handle_ris(RunesTerm *t)
 {
-    runes_display_use_normal_buffer(t);
-    runes_display_set_scroll_region(t, 0, t->rows - 1, 0, t->cols - 1);
-    runes_display_clear_screen(t);
-    runes_display_save_cursor(t);
-    runes_display_reset_text_attributes(t);
-    runes_display_show_cursor(t);
-
-    t->application_keypad            = 0;
-    t->application_cursor            = 0;
-    t->mouse_reporting_press         = 0;
-    t->mouse_reporting_press_release = 0;
+    runes_screen_use_normal_buffer(t);
+    runes_screen_set_scroll_region(
+        t, 0, t->scr.max.row - 1, 0, t->scr.max.col - 1);
+    runes_screen_clear_screen(t);
+    runes_screen_save_cursor(t);
+    runes_screen_reset_text_attributes(t);
+    runes_screen_show_cursor(t);
+    runes_screen_reset_application_keypad(t);
+    runes_screen_reset_application_cursor(t);
+    runes_screen_reset_mouse_reporting_press(t);
+    runes_screen_reset_mouse_reporting_press_release(t);
 }
 
 static void runes_parser_handle_vb(RunesTerm *t)
 {
-    runes_window_backend_request_visual_bell(t);
+    runes_screen_visual_bell(t);
 }
 
 static void runes_parser_handle_decsc(RunesTerm *t)
 {
-    runes_display_save_cursor(t);
+    runes_screen_save_cursor(t);
 }
 
 static void runes_parser_handle_decrc(RunesTerm *t)
 {
-    runes_display_restore_cursor(t);
+    runes_screen_restore_cursor(t);
 }
 
 static void runes_parser_extract_csi_params(
@@ -373,7 +357,7 @@ static void runes_parser_handle_ich(RunesTerm *t, char *buf, size_t len)
     int params[RUNES_PARSER_CSI_MAX_PARAMS] = { 1 }, nparams;
 
     runes_parser_extract_csi_params(buf + 2, len - 3, params, &nparams);
-    runes_display_insert_characters(t, params[0]);
+    runes_screen_insert_characters(t, params[0]);
 }
 
 static void runes_parser_handle_cuu(RunesTerm *t, char *buf, size_t len)
@@ -381,7 +365,7 @@ static void runes_parser_handle_cuu(RunesTerm *t, char *buf, size_t len)
     int params[RUNES_PARSER_CSI_MAX_PARAMS] = { 1 }, nparams;
 
     runes_parser_extract_csi_params(buf + 2, len - 3, params, &nparams);
-    runes_display_move_to(t, t->row - params[0], t->col);
+    runes_screen_move_to(t, t->scr.cur.row - params[0], t->scr.cur.col);
 }
 
 static void runes_parser_handle_cud(RunesTerm *t, char *buf, size_t len)
@@ -389,7 +373,7 @@ static void runes_parser_handle_cud(RunesTerm *t, char *buf, size_t len)
     int params[RUNES_PARSER_CSI_MAX_PARAMS] = { 1 }, nparams;
 
     runes_parser_extract_csi_params(buf + 2, len - 3, params, &nparams);
-    runes_display_move_to(t, t->row + params[0], t->col);
+    runes_screen_move_to(t, t->scr.cur.row + params[0], t->scr.cur.col);
 }
 
 static void runes_parser_handle_cuf(RunesTerm *t, char *buf, size_t len)
@@ -397,7 +381,7 @@ static void runes_parser_handle_cuf(RunesTerm *t, char *buf, size_t len)
     int params[RUNES_PARSER_CSI_MAX_PARAMS] = { 1 }, nparams;
 
     runes_parser_extract_csi_params(buf + 2, len - 3, params, &nparams);
-    runes_display_move_to(t, t->row, t->col + params[0]);
+    runes_screen_move_to(t, t->scr.cur.row, t->scr.cur.col + params[0]);
 }
 
 static void runes_parser_handle_cub(RunesTerm *t, char *buf, size_t len)
@@ -405,7 +389,7 @@ static void runes_parser_handle_cub(RunesTerm *t, char *buf, size_t len)
     int params[RUNES_PARSER_CSI_MAX_PARAMS] = { 1 }, nparams;
 
     runes_parser_extract_csi_params(buf + 2, len - 3, params, &nparams);
-    runes_display_move_to(t, t->row, t->col - params[0]);
+    runes_screen_move_to(t, t->scr.cur.row, t->scr.cur.col - params[0]);
 }
 
 static void runes_parser_handle_cup(RunesTerm *t, char *buf, size_t len)
@@ -419,7 +403,7 @@ static void runes_parser_handle_cup(RunesTerm *t, char *buf, size_t len)
     if (params[1] == 0) {
         params[1] = 1;
     }
-    runes_display_move_to(t, params[0] - 1, params[1] - 1);
+    runes_screen_move_to(t, params[0] - 1, params[1] - 1);
 }
 
 static void runes_parser_handle_ed(RunesTerm *t, char *buf, size_t len)
@@ -429,14 +413,13 @@ static void runes_parser_handle_ed(RunesTerm *t, char *buf, size_t len)
     runes_parser_extract_csi_params(buf + 2, len - 3, params, &nparams);
     switch (params[0]) {
     case 0:
-        runes_display_clear_screen_forward(t);
+        runes_screen_clear_screen_forward(t);
         break;
     case 1:
-        /* XXX */
-        fprintf(stderr, "unhandled ED parameter 1\n");
+        runes_screen_clear_screen_backward(t);
         break;
     case 2:
-        runes_display_clear_screen(t);
+        runes_screen_clear_screen(t);
         break;
     default:
         fprintf(stderr, "unknown ED parameter %d\n", params[0]);
@@ -451,14 +434,13 @@ static void runes_parser_handle_el(RunesTerm *t, char *buf, size_t len)
     runes_parser_extract_csi_params(buf + 2, len - 3, params, &nparams);
     switch (params[0]) {
     case 0:
-        runes_display_kill_line_forward(t);
+        runes_screen_kill_line_forward(t);
         break;
     case 1:
-        runes_display_kill_line_backward(t);
+        runes_screen_kill_line_backward(t);
         break;
     case 2:
-        runes_display_kill_line_forward(t);
-        runes_display_kill_line_backward(t);
+        runes_screen_kill_line(t);
         break;
     default:
         fprintf(stderr, "unknown EL parameter %d\n", params[0]);
@@ -471,8 +453,8 @@ static void runes_parser_handle_il(RunesTerm *t, char *buf, size_t len)
     int params[RUNES_PARSER_CSI_MAX_PARAMS] = { 1 }, nparams;
 
     runes_parser_extract_csi_params(buf + 2, len - 3, params, &nparams);
-    runes_display_insert_lines(t, params[0]);
-    runes_display_move_to(t, t->row, 0);
+    runes_screen_insert_lines(t, params[0]);
+    runes_screen_move_to(t, t->scr.cur.row, 0);
 }
 
 static void runes_parser_handle_dl(RunesTerm *t, char *buf, size_t len)
@@ -480,8 +462,8 @@ static void runes_parser_handle_dl(RunesTerm *t, char *buf, size_t len)
     int params[RUNES_PARSER_CSI_MAX_PARAMS] = { 1 }, nparams;
 
     runes_parser_extract_csi_params(buf + 2, len - 3, params, &nparams);
-    runes_display_delete_lines(t, params[0]);
-    runes_display_move_to(t, t->row, 0);
+    runes_screen_delete_lines(t, params[0]);
+    runes_screen_move_to(t, t->scr.cur.row, 0);
 }
 
 static void runes_parser_handle_dch(RunesTerm *t, char *buf, size_t len)
@@ -489,7 +471,7 @@ static void runes_parser_handle_dch(RunesTerm *t, char *buf, size_t len)
     int params[RUNES_PARSER_CSI_MAX_PARAMS] = { 1 }, nparams;
 
     runes_parser_extract_csi_params(buf + 2, len - 3, params, &nparams);
-    runes_display_delete_characters(t, params[0]);
+    runes_screen_delete_characters(t, params[0]);
 }
 
 static void runes_parser_handle_sm(RunesTerm *t, char *buf, size_t len)
@@ -515,20 +497,20 @@ static void runes_parser_handle_sm(RunesTerm *t, char *buf, size_t len)
         case '?':
             switch (params[i]) {
             case 1:
-                t->application_cursor = 1;
+                runes_screen_set_application_cursor(t);
                 break;
             case 9:
-                t->mouse_reporting_press = 1;
+                runes_screen_set_mouse_reporting_press(t);
                 break;
             case 25:
-                runes_display_show_cursor(t);
+                runes_screen_show_cursor(t);
                 break;
             case 1000:
-                t->mouse_reporting_press_release = 1;
+                runes_screen_set_mouse_reporting_press_release(t);
                 break;
             case 47:
             case 1049:
-                runes_display_use_alternate_buffer(t);
+                runes_screen_use_alternate_buffer(t);
                 break;
             default:
                 fprintf(
@@ -569,20 +551,20 @@ static void runes_parser_handle_rm(RunesTerm *t, char *buf, size_t len)
         case '?':
             switch (params[i]) {
             case 1:
-                t->application_cursor = 0;
+                runes_screen_set_application_cursor(t);
                 break;
             case 9:
-                t->mouse_reporting_press = 0;
+                runes_screen_set_mouse_reporting_press(t);
                 break;
             case 25:
-                runes_display_hide_cursor(t);
+                runes_screen_hide_cursor(t);
                 break;
             case 1000:
-                t->mouse_reporting_press_release = 0;
+                runes_screen_set_mouse_reporting_press_release(t);
                 break;
             case 47:
             case 1049:
-                runes_display_use_normal_buffer(t);
+                runes_screen_use_normal_buffer(t);
                 break;
             default:
                 fprintf(
@@ -611,35 +593,35 @@ static void runes_parser_handle_sgr(RunesTerm *t, char *buf, size_t len)
     for (i = 0; i < nparams; ++i) {
         switch (params[i]) {
         case 0:
-            runes_display_reset_text_attributes(t);
+            runes_screen_reset_text_attributes(t);
             break;
         case 1:
-            runes_display_set_bold(t);
+            runes_screen_set_bold(t);
             break;
         case 3:
-            runes_display_set_italic(t);
+            runes_screen_set_italic(t);
             break;
         case 4:
-            runes_display_set_underline(t);
+            runes_screen_set_underline(t);
             break;
         case 7:
-            runes_display_set_inverse(t);
+            runes_screen_set_inverse(t);
             break;
         case 22:
-            runes_display_reset_bold(t);
+            runes_screen_reset_bold(t);
             break;
         case 23:
-            runes_display_reset_italic(t);
+            runes_screen_reset_italic(t);
             break;
         case 24:
-            runes_display_reset_underline(t);
+            runes_screen_reset_underline(t);
             break;
         case 27:
-            runes_display_reset_inverse(t);
+            runes_screen_reset_inverse(t);
             break;
         case 30: case 31: case 32: case 33:
         case 34: case 35: case 36: case 37:
-            runes_display_set_fg_color(t, params[i] - 30);
+            runes_screen_set_fg_color(t, params[i] - 30);
             break;
         case 38: {
             i++;
@@ -660,7 +642,7 @@ static void runes_parser_handle_sgr(RunesTerm *t, char *buf, size_t len)
                         params[i - 4], params[i - 3]);
                     break;
                 }
-                runes_display_set_fg_color_rgb(
+                runes_screen_set_fg_color_rgb(
                     t, params[i - 2], params[i - 1], params[i]);
                 break;
             case 5:
@@ -672,7 +654,7 @@ static void runes_parser_handle_sgr(RunesTerm *t, char *buf, size_t len)
                         params[i - 2], params[i - 1]);
                     break;
                 }
-                runes_display_set_fg_color(t, params[i]);
+                runes_screen_set_fg_color(t, params[i]);
                 break;
             default:
                 i++;
@@ -684,11 +666,11 @@ static void runes_parser_handle_sgr(RunesTerm *t, char *buf, size_t len)
             break;
         }
         case 39:
-            runes_display_reset_fg_color(t);
+            runes_screen_reset_fg_color(t);
             break;
         case 40: case 41: case 42: case 43:
         case 44: case 45: case 46: case 47:
-            runes_display_set_bg_color(t, params[i] - 40);
+            runes_screen_set_bg_color(t, params[i] - 40);
             break;
         case 48: {
             i++;
@@ -709,7 +691,7 @@ static void runes_parser_handle_sgr(RunesTerm *t, char *buf, size_t len)
                         params[i - 4], params[i - 3]);
                     break;
                 }
-                runes_display_set_bg_color_rgb(
+                runes_screen_set_bg_color_rgb(
                     t, params[i - 2], params[i - 1], params[i]);
                 break;
             case 5:
@@ -721,7 +703,7 @@ static void runes_parser_handle_sgr(RunesTerm *t, char *buf, size_t len)
                         params[i - 2], params[i - 1]);
                     break;
                 }
-                runes_display_set_bg_color(t, params[i]);
+                runes_screen_set_bg_color(t, params[i]);
                 break;
             default:
                 i++;
@@ -733,15 +715,15 @@ static void runes_parser_handle_sgr(RunesTerm *t, char *buf, size_t len)
             break;
         }
         case 49:
-            runes_display_reset_bg_color(t);
+            runes_screen_reset_bg_color(t);
             break;
         case 90: case 91: case 92: case 93:
         case 94: case 95: case 96: case 97:
-            runes_display_set_fg_color(t, params[i] - 82);
+            runes_screen_set_fg_color(t, params[i] - 82);
             break;
         case 100: case 101: case 102: case 103:
         case 104: case 105: case 106: case 107:
-            runes_display_set_bg_color(t, params[i] - 92);
+            runes_screen_set_bg_color(t, params[i] - 92);
             break;
         default:
             fprintf(stderr, "unknown SGR parameter: %d\n", params[i]);
@@ -752,12 +734,13 @@ static void runes_parser_handle_sgr(RunesTerm *t, char *buf, size_t len)
 
 static void runes_parser_handle_csr(RunesTerm *t, char *buf, size_t len)
 {
-    int params[RUNES_PARSER_CSI_MAX_PARAMS] = { 1, t->rows, 1, t->cols };
+    int params[RUNES_PARSER_CSI_MAX_PARAMS] = {
+        1, t->scr.max.row, 1, t->scr.max.col };
     int nparams;
 
     runes_parser_extract_csi_params(buf + 2, len - 3, params, &nparams);
 
-    runes_display_set_scroll_region(
+    runes_screen_set_scroll_region(
         t, params[0] - 1, params[1] - 1, params[2] - 1, params[3] - 1);
 }
 
@@ -769,7 +752,7 @@ static void runes_parser_handle_decsed(RunesTerm *t, char *buf, size_t len)
     switch (params[0]) {
     case 0:
         /* XXX not quite correct */
-        runes_display_clear_screen_forward(t);
+        runes_screen_clear_screen_forward(t);
         break;
     case 1:
         /* XXX */
@@ -777,7 +760,7 @@ static void runes_parser_handle_decsed(RunesTerm *t, char *buf, size_t len)
         break;
     case 2:
         /* XXX not quite correct */
-        runes_display_clear_screen(t);
+        runes_screen_clear_screen(t);
         break;
     default:
         fprintf(stderr, "unknown DECSED parameter %d\n", params[0]);
@@ -793,7 +776,7 @@ static void runes_parser_handle_decsel(RunesTerm *t, char *buf, size_t len)
     switch (params[0]) {
     case 0:
         /* XXX not quite correct */
-        runes_display_kill_line_forward(t);
+        runes_screen_kill_line_forward(t);
         break;
     case 1:
         /* XXX */
@@ -811,28 +794,28 @@ static void runes_parser_handle_decsel(RunesTerm *t, char *buf, size_t len)
 
 static void runes_parser_handle_osc0(RunesTerm *t, char *buf, size_t len)
 {
-    runes_window_backend_set_icon_name(t, buf + 4, len - 5);
-    runes_window_backend_set_window_title(t, buf + 4, len - 5);
+    runes_screen_set_icon_name(t, buf + 4, len - 5);
+    runes_screen_set_window_title(t, buf + 4, len - 5);
 }
 
 static void runes_parser_handle_osc1(RunesTerm *t, char *buf, size_t len)
 {
-    runes_window_backend_set_icon_name(t, buf + 4, len - 5);
+    runes_screen_set_icon_name(t, buf + 4, len - 5);
 }
 
 static void runes_parser_handle_osc2(RunesTerm *t, char *buf, size_t len)
 {
-    runes_window_backend_set_window_title(t, buf + 4, len - 5);
+    runes_screen_set_window_title(t, buf + 4, len - 5);
 }
 
 static void runes_parser_handle_ascii(RunesTerm *t, char *text, size_t len)
 {
-    runes_display_show_string_ascii(t, text, len);
+    runes_screen_show_string_ascii(t, text, len);
 }
 
 static void runes_parser_handle_text(RunesTerm *t, char *text, size_t len)
 {
-    runes_display_show_string_utf8(t, text, len);
+    runes_screen_show_string_utf8(t, text, len);
 }
 
 /* XXX these are copied from the generated file so that I can add the UNUSED
diff --git a/src/pty-unix.c b/src/pty-unix.c
index 0a4dc8b..c969394 100644
--- a/src/pty-unix.c
+++ b/src/pty-unix.c
@@ -99,8 +99,8 @@ void runes_pty_backend_set_window_size(RunesTerm *t)
 {
     struct winsize size;
 
-    size.ws_row = t->rows;
-    size.ws_col = t->cols;
+    size.ws_row = t->scr.max.row;
+    size.ws_col = t->scr.max.col;
     size.ws_xpixel = t->xpixel;
     size.ws_ypixel = t->ypixel;
     ioctl(t->pty.master, TIOCSWINSZ, &size);
@@ -144,7 +144,7 @@ static void runes_pty_backend_got_data(uv_work_t *req, int status)
     UNUSED(status);
 
     if (t->readlen > 0) {
-        runes_parser_process_string(
+        runes_screen_process_string(
             t, t->readbuf, t->readlen + t->remaininglen);
         uv_queue_work(
             t->loop, req, runes_pty_backend_read, runes_pty_backend_got_data);
diff --git a/src/runes.h b/src/runes.h
index 8c2861b..d4e8d9f 100644
--- a/src/runes.h
+++ b/src/runes.h
@@ -10,11 +10,13 @@
 struct runes_term;
 struct runes_window;
 struct runes_pty;
+struct runes_screen;
 struct runes_loop_data;
 
 typedef struct runes_term RunesTerm;
 typedef struct runes_window RunesWindowBackend;
 typedef struct runes_pty RunesPtyBackend;
+typedef struct runes_screen RunesScreen;
 typedef struct runes_loop_data RunesLoopData;
 
 struct runes_loop_data {
@@ -25,9 +27,9 @@ struct runes_loop_data {
 #include "window-xlib.h"
 #include "pty-unix.h"
 
+#include "screen.h"
 #include "term.h"
 #include "display.h"
-#include "parser.h"
 #include "config.h"
 
 #define UNUSED(x) ((void)x)
diff --git a/src/screen.c b/src/screen.c
new file mode 100644
index 0000000..b8e903a
--- /dev/null
+++ b/src/screen.c
@@ -0,0 +1,369 @@
+#include <stdlib.h>
+#include <string.h>
+
+#include "runes.h"
+#include "parser.h"
+
+void runes_screen_init(RunesTerm *t)
+{
+    int i;
+
+    t->scr.rows = calloc(t->scr.max.row, sizeof(struct runes_row));
+    for (i = 0; i < t->scr.max.row; ++i) {
+        t->scr.rows[i].cells = calloc(
+            t->scr.max.col, sizeof(struct runes_cell));
+    }
+}
+
+void runes_screen_process_string(RunesTerm *t, char *buf, size_t len)
+{
+    YY_BUFFER_STATE state;
+    yyscan_t scanner;
+    int remaining;
+
+    /* XXX this will break if buf ends with a partial escape sequence or utf8
+     * character. we need to detect that and not consume the entire input in
+     * that case */
+    runes_parser_yylex_init_extra(t, &scanner);
+    state = runes_parser_yy_scan_bytes(buf, len, scanner);
+    while ((remaining = runes_parser_yylex(scanner)) == -1);
+    t->remaininglen = remaining;
+    if (t->remaininglen) {
+        memmove(t->readbuf, &buf[len - t->remaininglen], t->remaininglen);
+    }
+    runes_parser_yy_delete_buffer(state, scanner);
+    runes_parser_yylex_destroy(scanner);
+
+    runes_display_draw_screen(t);
+}
+
+void runes_screen_audible_bell(RunesTerm *t)
+{
+    UNUSED(t);
+    fprintf(stderr, "audible_bell nyi\n");
+}
+
+void runes_screen_visual_bell(RunesTerm *t)
+{
+    UNUSED(t);
+    fprintf(stderr, "visual_bell nyi\n");
+}
+
+void runes_screen_show_string_ascii(RunesTerm *t, char *buf, size_t len)
+{
+    RunesScreen *scr = &t->scr;
+    size_t i;
+
+    for (i = 0; i < len; ++i) {
+        struct runes_cell *cell = &scr->rows[scr->cur.row].cells[scr->cur.col];
+
+        cell->contents[0] = buf[i];
+        cell->contents[1] = '\0';
+        cell->len = 1;
+
+        scr->cur.col++;
+        if (scr->cur.col >= scr->max.col) {
+            scr->cur.col = 0;
+            scr->cur.row++;
+        }
+    }
+}
+
+void runes_screen_show_string_utf8(RunesTerm *t, char *buf, size_t len)
+{
+    UNUSED(t);
+    UNUSED(buf);
+    UNUSED(len);
+    fprintf(stderr, "show_string_utf8 nyi\n");
+}
+
+void runes_screen_move_to(RunesTerm *t, int row, int col)
+{
+    RunesScreen *scr = &t->scr;
+
+    scr->cur.row = row;
+    scr->cur.col = col;
+}
+
+void runes_screen_clear_screen(RunesTerm *t)
+{
+    UNUSED(t);
+    fprintf(stderr, "clear_screen nyi\n");
+}
+
+void runes_screen_clear_screen_forward(RunesTerm *t)
+{
+    UNUSED(t);
+    fprintf(stderr, "clear_screen_forward nyi\n");
+}
+
+void runes_screen_clear_screen_backward(RunesTerm *t)
+{
+    UNUSED(t);
+    fprintf(stderr, "clear_screen_backward nyi\n");
+}
+
+void runes_screen_kill_line(RunesTerm *t)
+{
+    UNUSED(t);
+    fprintf(stderr, "kill_line nyi\n");
+}
+
+void runes_screen_kill_line_forward(RunesTerm *t)
+{
+    UNUSED(t);
+    fprintf(stderr, "kill_line_forward nyi\n");
+}
+
+void runes_screen_kill_line_backward(RunesTerm *t)
+{
+    UNUSED(t);
+    fprintf(stderr, "kill_line_backward nyi\n");
+}
+
+void runes_screen_insert_characters(RunesTerm *t, int count)
+{
+    UNUSED(t);
+    UNUSED(count);
+    fprintf(stderr, "insert_characters nyi\n");
+}
+
+void runes_screen_insert_lines(RunesTerm *t, int count)
+{
+    UNUSED(t);
+    UNUSED(count);
+    fprintf(stderr, "insert_lines nyi\n");
+}
+
+void runes_screen_delete_characters(RunesTerm *t, int count)
+{
+    UNUSED(t);
+    UNUSED(count);
+    fprintf(stderr, "delete_characters nyi\n");
+}
+
+void runes_screen_delete_lines(RunesTerm *t, int count)
+{
+    UNUSED(t);
+    UNUSED(count);
+    fprintf(stderr, "delete_lines nyi\n");
+}
+
+void runes_screen_set_scroll_region(
+    RunesTerm *t, int top, int bottom, int left, int right)
+{
+    UNUSED(t);
+    UNUSED(top);
+    UNUSED(bottom);
+    UNUSED(left);
+    UNUSED(right);
+    fprintf(stderr, "set_scroll_region nyi\n");
+}
+
+void runes_screen_reset_text_attributes(RunesTerm *t)
+{
+    UNUSED(t);
+    fprintf(stderr, "reset_text_attributes nyi\n");
+}
+
+void runes_screen_set_fg_color(RunesTerm *t, int idx)
+{
+    UNUSED(t);
+    UNUSED(idx);
+    fprintf(stderr, "set_fg_color nyi\n");
+}
+
+void runes_screen_set_fg_color_rgb(RunesTerm *t, int r, int g, int b)
+{
+    UNUSED(t);
+    UNUSED(r);
+    UNUSED(g);
+    UNUSED(b);
+    fprintf(stderr, "set_fg_color_rgb nyi\n");
+}
+
+void runes_screen_reset_fg_color(RunesTerm *t)
+{
+    UNUSED(t);
+    fprintf(stderr, "reset_fg_color nyi\n");
+}
+
+void runes_screen_set_bg_color(RunesTerm *t, int idx)
+{
+    UNUSED(t);
+    UNUSED(idx);
+    fprintf(stderr, "set_bg_color nyi\n");
+}
+
+void runes_screen_set_bg_color_rgb(RunesTerm *t, int r, int g, int b)
+{
+    UNUSED(t);
+    UNUSED(r);
+    UNUSED(g);
+    UNUSED(b);
+    fprintf(stderr, "set_bg_color_rgb nyi\n");
+}
+
+void runes_screen_reset_bg_color(RunesTerm *t)
+{
+    UNUSED(t);
+    fprintf(stderr, "reset_bg_color nyi\n");
+}
+
+void runes_screen_set_bold(RunesTerm *t)
+{
+    UNUSED(t);
+    fprintf(stderr, "set_bold nyi\n");
+}
+
+void runes_screen_set_italic(RunesTerm *t)
+{
+    UNUSED(t);
+    fprintf(stderr, "set_italic nyi\n");
+}
+
+void runes_screen_set_underline(RunesTerm *t)
+{
+    UNUSED(t);
+    fprintf(stderr, "set_underline nyi\n");
+}
+
+void runes_screen_set_inverse(RunesTerm *t)
+{
+    UNUSED(t);
+    fprintf(stderr, "set_inverse nyi\n");
+}
+
+void runes_screen_reset_bold(RunesTerm *t)
+{
+    UNUSED(t);
+    fprintf(stderr, "reset_bold nyi\n");
+}
+
+void runes_screen_reset_italic(RunesTerm *t)
+{
+    UNUSED(t);
+    fprintf(stderr, "reset_italic nyi\n");
+}
+
+void runes_screen_reset_underline(RunesTerm *t)
+{
+    UNUSED(t);
+    fprintf(stderr, "reset_underline nyi\n");
+}
+
+void runes_screen_reset_inverse(RunesTerm *t)
+{
+    UNUSED(t);
+    fprintf(stderr, "reset_inverse nyi\n");
+}
+
+void runes_screen_use_alternate_buffer(RunesTerm *t)
+{
+    UNUSED(t);
+    fprintf(stderr, "use_alternate_buffer nyi\n");
+}
+
+void runes_screen_use_normal_buffer(RunesTerm *t)
+{
+    UNUSED(t);
+    fprintf(stderr, "use_normal_buffer nyi\n");
+}
+
+void runes_screen_save_cursor(RunesTerm *t)
+{
+    UNUSED(t);
+    fprintf(stderr, "save_cursor nyi\n");
+}
+
+void runes_screen_restore_cursor(RunesTerm *t)
+{
+    UNUSED(t);
+    fprintf(stderr, "restore_cursor nyi\n");
+}
+
+void runes_screen_show_cursor(RunesTerm *t)
+{
+    UNUSED(t);
+    fprintf(stderr, "show_cursor nyi\n");
+}
+
+void runes_screen_hide_cursor(RunesTerm *t)
+{
+    UNUSED(t);
+    fprintf(stderr, "hide_cursor nyi\n");
+}
+
+void runes_screen_set_application_keypad(RunesTerm *t)
+{
+    UNUSED(t);
+    fprintf(stderr, "set_application_keypad nyi\n");
+}
+
+void runes_screen_reset_application_keypad(RunesTerm *t)
+{
+    UNUSED(t);
+    fprintf(stderr, "reset_application_keypad nyi\n");
+}
+
+void runes_screen_set_application_cursor(RunesTerm *t)
+{
+    UNUSED(t);
+    fprintf(stderr, "set_application_cursor nyi\n");
+}
+
+void runes_screen_reset_application_cursor(RunesTerm *t)
+{
+    UNUSED(t);
+    fprintf(stderr, "reset_application_cursor nyi\n");
+}
+
+void runes_screen_set_mouse_reporting_press(RunesTerm *t)
+{
+    UNUSED(t);
+    fprintf(stderr, "set_mouse_reporting_press nyi\n");
+}
+
+void runes_screen_reset_mouse_reporting_press(RunesTerm *t)
+{
+    UNUSED(t);
+    fprintf(stderr, "reset_mouse_reporting_press nyi\n");
+}
+
+void runes_screen_set_mouse_reporting_press_release(RunesTerm *t)
+{
+    UNUSED(t);
+    fprintf(stderr, "set_mouse_reporting_press_release nyi\n");
+}
+
+void runes_screen_reset_mouse_reporting_press_release(RunesTerm *t)
+{
+    UNUSED(t);
+    fprintf(stderr, "reset_mouse_reporting_press_release nyi\n");
+}
+
+void runes_screen_set_window_title(RunesTerm *t, char *buf, size_t len)
+{
+    UNUSED(t);
+    UNUSED(buf);
+    UNUSED(len);
+    fprintf(stderr, "set_window_title nyi\n");
+}
+
+void runes_screen_set_icon_name(RunesTerm *t, char *buf, size_t len)
+{
+    UNUSED(t);
+    UNUSED(buf);
+    UNUSED(len);
+    fprintf(stderr, "set_icon_name nyi\n");
+}
+
+void runes_screen_cleanup(RunesTerm *t)
+{
+    int i;
+
+    for (i = 0; i < t->scr.max.row; ++i) {
+        free(t->scr.rows[i].cells);
+    }
+    free(t->scr.rows);
+}
diff --git a/src/screen.h b/src/screen.h
new file mode 100644
index 0000000..77f12f2
--- /dev/null
+++ b/src/screen.h
@@ -0,0 +1,128 @@
+#ifndef _RUNES_SCREEN_H
+#define _RUNES_SCREEN_H
+
+enum RunesColorType {
+    RUNES_COLOR_DEFAULT,
+    RUNES_COLOR_IDX,
+    RUNES_COLOR_RGB
+};
+
+struct runes_loc {
+    int row;
+    int col;
+};
+
+struct runes_color {
+    union {
+        struct {
+            unsigned char r;
+            unsigned char g;
+            unsigned char b;
+        };
+        unsigned char idx;
+    };
+    unsigned char type;
+};
+
+struct runes_cell {
+    char contents[8];
+    size_t len;
+    struct runes_color fgcolor;
+    struct runes_color bgcolor;
+    unsigned char bold: 1;
+    unsigned char italic: 1;
+    unsigned char underline: 1;
+    unsigned char inverse: 1;
+};
+
+struct runes_row {
+    struct runes_cell *cells;
+    unsigned char dirty: 1;
+};
+
+struct runes_screen {
+    struct runes_loc cur;
+    struct runes_loc max;
+    struct runes_loc saved;
+
+    int scroll_top;
+    int scroll_bottom;
+
+    char *title;
+    char *icon_name;
+
+    struct runes_row *rows;
+
+    struct runes_color fgcolor;
+    struct runes_color bgcolor;
+
+    unsigned char bold: 1;
+    unsigned char italic: 1;
+    unsigned char underline: 1;
+    unsigned char inverse: 1;
+
+    unsigned char hide_cursor: 1;
+    unsigned char application_keypad: 1;
+    unsigned char application_cursor: 1;
+    unsigned char mouse_reporting_press: 1;
+    unsigned char mouse_reporting_press_release: 1;
+
+    unsigned char visual_bell: 1;
+    unsigned char audible_bell: 1;
+    unsigned char update_title: 1;
+    unsigned char update_icon_name: 1;
+};
+
+void runes_screen_init(RunesTerm *t);
+void runes_screen_process_string(RunesTerm *t, char *buf, size_t len);
+void runes_screen_audible_bell(RunesTerm *t);
+void runes_screen_visual_bell(RunesTerm *t);
+void runes_screen_show_string_ascii(RunesTerm *t, char *buf, size_t len);
+void runes_screen_show_string_utf8(RunesTerm *t, char *buf, size_t len);
+void runes_screen_move_to(RunesTerm *t, int row, int col);
+void runes_screen_clear_screen(RunesTerm *t);
+void runes_screen_clear_screen_forward(RunesTerm *t);
+void runes_screen_clear_screen_backward(RunesTerm *t);
+void runes_screen_kill_line(RunesTerm *t);
+void runes_screen_kill_line_forward(RunesTerm *t);
+void runes_screen_kill_line_backward(RunesTerm *t);
+void runes_screen_insert_characters(RunesTerm *t, int count);
+void runes_screen_insert_lines(RunesTerm *t, int count);
+void runes_screen_delete_characters(RunesTerm *t, int count);
+void runes_screen_delete_lines(RunesTerm *t, int count);
+void runes_screen_set_scroll_region(
+    RunesTerm *t, int top, int bottom, int left, int right);
+void runes_screen_reset_text_attributes(RunesTerm *t);
+void runes_screen_set_fg_color(RunesTerm *t, int idx);
+void runes_screen_set_fg_color_rgb(RunesTerm *t, int r, int g, int b);
+void runes_screen_reset_fg_color(RunesTerm *t);
+void runes_screen_set_bg_color(RunesTerm *t, int idx);
+void runes_screen_set_bg_color_rgb(RunesTerm *t, int r, int g, int b);
+void runes_screen_reset_bg_color(RunesTerm *t);
+void runes_screen_set_bold(RunesTerm *t);
+void runes_screen_set_italic(RunesTerm *t);
+void runes_screen_set_underline(RunesTerm *t);
+void runes_screen_set_inverse(RunesTerm *t);
+void runes_screen_reset_bold(RunesTerm *t);
+void runes_screen_reset_italic(RunesTerm *t);
+void runes_screen_reset_underline(RunesTerm *t);
+void runes_screen_reset_inverse(RunesTerm *t);
+void runes_screen_use_alternate_buffer(RunesTerm *t);
+void runes_screen_use_normal_buffer(RunesTerm *t);
+void runes_screen_save_cursor(RunesTerm *t);
+void runes_screen_restore_cursor(RunesTerm *t);
+void runes_screen_show_cursor(RunesTerm *t);
+void runes_screen_hide_cursor(RunesTerm *t);
+void runes_screen_set_application_keypad(RunesTerm *t);
+void runes_screen_reset_application_keypad(RunesTerm *t);
+void runes_screen_set_application_cursor(RunesTerm *t);
+void runes_screen_reset_application_cursor(RunesTerm *t);
+void runes_screen_set_mouse_reporting_press(RunesTerm *t);
+void runes_screen_reset_mouse_reporting_press(RunesTerm *t);
+void runes_screen_set_mouse_reporting_press_release(RunesTerm *t);
+void runes_screen_reset_mouse_reporting_press_release(RunesTerm *t);
+void runes_screen_set_window_title(RunesTerm *t, char *buf, size_t len);
+void runes_screen_set_icon_name(RunesTerm *t, char *buf, size_t len);
+void runes_screen_destroy(RunesTerm *t);
+
+#endif
diff --git a/src/term.c b/src/term.c
index 34cb4c7..21f2d1d 100644
--- a/src/term.c
+++ b/src/term.c
@@ -9,6 +9,7 @@ void runes_term_init(RunesTerm *t, int argc, char *argv[])
     runes_pty_backend_spawn_subprocess(t);
 
     runes_display_set_window_size(t);
+    runes_screen_init(t);
 
     t->loop = uv_default_loop();
     runes_window_backend_start_loop(t);
diff --git a/src/term.h b/src/term.h
index 71e0bcc..6baf961 100644
--- a/src/term.h
+++ b/src/term.h
@@ -4,12 +4,26 @@
 struct runes_term {
     RunesWindowBackend w;
     RunesPtyBackend pty;
+    RunesScreen scr;
 
     cairo_t *cr;
     cairo_t *backend_cr;
-    cairo_t *alternate_cr;
     uv_loop_t *loop;
 
+    PangoLayout *layout;
+
+    char readbuf[RUNES_READ_BUFFER_LENGTH];
+    int readlen;
+    int remaininglen;
+
+    int xpixel;
+    int ypixel;
+    int fontx;
+    int fonty;
+
+    char visual_bell_is_ringing;
+    char unfocused;
+
     cairo_pattern_t *mousecursorcolor;
     cairo_pattern_t *cursorcolor;
 
@@ -19,48 +33,16 @@ struct runes_term {
     cairo_pattern_t *fgcustom;
     cairo_pattern_t *bgcustom;
 
-    int fgcolor;
-    int bgcolor;
-
-    int row;
-    int col;
-    int saved_row;
-    int saved_col;
-    int scroll_top;
-    int scroll_bottom;
-
-    int rows;
-    int cols;
-    int xpixel;
-    int ypixel;
-    int fontx;
-    int fonty;
     int default_rows;
     int default_cols;
 
     char *cmd;
-
     char *font_name;
-    PangoLayout *layout;
-
-    char readbuf[RUNES_READ_BUFFER_LENGTH];
-    int readlen;
-    int remaininglen;
 
     char bell_is_urgent;
     char bold_is_bright;
     char bold_is_bold;
-    char bold;
-    char inverse;
-    char hide_cursor;
-    char unfocused;
     char audible_bell;
-    char visual_bell_is_ringing;
-
-    char application_keypad;
-    char application_cursor;
-    char mouse_reporting_press;
-    char mouse_reporting_press_release;
 };
 
 void runes_term_init(RunesTerm *t, int argc, char *argv[]);
diff --git a/src/window-xlib.c b/src/window-xlib.c
index 5cd2b04..fcb13ef 100644
--- a/src/window-xlib.c
+++ b/src/window-xlib.c
@@ -498,21 +498,22 @@ static void runes_window_backend_audible_bell(RunesTerm *t)
 
 static void runes_window_backend_draw_cursor(RunesTerm *t)
 {
-    if (!t->hide_cursor) {
+    if (!t->scr.hide_cursor) {
         cairo_save(t->backend_cr);
         cairo_set_source(t->backend_cr, t->cursorcolor);
         if (t->unfocused) {
             cairo_set_line_width(t->backend_cr, 1);
             cairo_rectangle(
                 t->backend_cr,
-                t->col * t->fontx + 0.5, t->row * t->fonty + 0.5,
+                t->scr.cur.col * t->fontx + 0.5,
+                t->scr.cur.row * t->fonty + 0.5,
                 t->fontx, t->fonty);
             cairo_stroke(t->backend_cr);
         }
         else {
             cairo_rectangle(
                 t->backend_cr,
-                t->col * t->fontx, t->row * t->fonty,
+                t->scr.cur.col * t->fontx, t->scr.cur.row * t->fonty,
                 t->fontx, t->fonty);
             cairo_fill(t->backend_cr);
         }
@@ -620,8 +621,8 @@ static struct function_key *runes_window_backend_find_key_sequence(
 {
     struct function_key *key;
 
-    if (t->application_keypad) {
-        if (t->application_cursor) {
+    if (t->scr.application_keypad) {
+        if (t->scr.application_cursor) {
             key = &application_cursor_keys[0];
             while (key->sym != XK_VoidSymbol) {
                 if (key->sym == sym) {
@@ -658,7 +659,7 @@ static void runes_window_backend_handle_button_event(
         }
     }
 
-    if (t->mouse_reporting_press_release) {
+    if (t->scr.mouse_reporting_press_release) {
         char response[7];
         char status = 0;
 
@@ -706,7 +707,7 @@ static void runes_window_backend_handle_button_event(
             ' ' + (e->y / t->fonty + 1));
         runes_pty_backend_write(t, response, 6);
     }
-    else if (t->mouse_reporting_press && e->type == ButtonPress) {
+    else if (t->scr.mouse_reporting_press && e->type == ButtonPress) {
         char response[7];
 
         sprintf(
@@ -762,10 +763,10 @@ static void runes_window_backend_handle_focus_event(
 {
     runes_window_backend_clear_urgent(t);
     if (e->type == FocusIn) {
-        runes_display_focus_in(t);
+        t->unfocused = 0;
     }
     else {
-        runes_display_focus_out(t);
+        t->unfocused = 1;
     }
     runes_window_backend_flush(t);
 }