handle wide characters

3 files changed, 21 insertions, 8 deletions

diff --git a/src/display.c b/src/display.c
index dff5173..02e7d1a 100644
--- a/src/display.c
+++ b/src/display.c
@@ -4,7 +4,7 @@
 #include "runes.h"
 
 static void runes_display_recalculate_font_metrics(RunesTerm *t);
-static void runes_display_draw_cell(RunesTerm *t, int row, int col);
+static int 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 row, int col, int width, int height);
@@ -91,12 +91,14 @@ void runes_display_set_window_size(RunesTerm *t)
 
 void runes_display_draw_screen(RunesTerm *t)
 {
-    int r, c;
+    int r;
 
     /* 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);
+        int c = 0;
+
+        while (c < t->scr.max.col) {
+            c += runes_display_draw_cell(t, r, c);
         }
     }
     runes_window_backend_request_flush(t);
@@ -148,7 +150,7 @@ static void runes_display_recalculate_font_metrics(RunesTerm *t)
     }
 }
 
-static void runes_display_draw_cell(RunesTerm *t, int row, int col)
+static int runes_display_draw_cell(RunesTerm *t, int row, int col)
 {
     struct runes_cell *cell = &t->scr.rows[row].cells[col];
     cairo_pattern_t *bg = NULL, *fg = NULL;
@@ -204,7 +206,8 @@ static void runes_display_draw_cell(RunesTerm *t, int row, int col)
         }
     }
 
-    runes_display_paint_rectangle(t, t->cr, bg, row, col, 1, 1);
+    runes_display_paint_rectangle(
+        t, t->cr, bg, row, col, cell->is_wide ? 2 : 1, 1);
 
     if (cell->len) {
         runes_display_draw_glyph(
@@ -218,6 +221,8 @@ static void runes_display_draw_cell(RunesTerm *t, int row, int col)
     if (fg_is_custom) {
         cairo_pattern_destroy(fg);
     }
+
+    return cell->is_wide ? 2 : 1;
 }
 
 static void runes_display_paint_rectangle(
diff --git a/src/screen.c b/src/screen.c
index 9d77ea3..1b460e6 100644
--- a/src/screen.c
+++ b/src/screen.c
@@ -69,6 +69,7 @@ void runes_screen_show_string_ascii(RunesTerm *t, char *buf, size_t len)
         cell->contents[0] = buf[i];
         cell->contents[1] = '\0';
         cell->attrs = scr->attrs;
+        cell->is_wide = 0;
 
         runes_screen_move_to(t, scr->cur.row, scr->cur.col + 1);
     }
@@ -83,17 +84,23 @@ void runes_screen_show_string_utf8(RunesTerm *t, char *buf, size_t len)
      * cell */
     while ((next = g_utf8_next_char(c))) {
         struct runes_cell *cell;
+        int is_wide;
 
-        if (scr->cur.col >= scr->max.col) {
+        /* XXX handle zero width characters */
+        is_wide = g_unichar_iswide(g_utf8_get_char(c));
+
+        if (scr->cur.col + (is_wide ? 2 : 1) > scr->max.col) {
             runes_screen_move_to(t, scr->cur.row + 1, 0);
         }
         cell = &scr->rows[scr->cur.row].cells[scr->cur.col];
+        cell->is_wide = is_wide;
 
         cell->len = next - c;
         strncpy(cell->contents, c, cell->len);
         cell->attrs = scr->attrs;
 
-        runes_screen_move_to(t, scr->cur.row, scr->cur.col + 1);
+        runes_screen_move_to(
+            t, scr->cur.row, scr->cur.col + (is_wide ? 2 : 1));
         c = next;
         if ((size_t)(c - buf) >= len) {
             break;
diff --git a/src/screen.h b/src/screen.h
index 73b9360..deddb81 100644
--- a/src/screen.h
+++ b/src/screen.h
@@ -49,6 +49,7 @@ struct runes_cell {
     char contents[8];
     size_t len;
     struct runes_cell_attrs attrs;
+    unsigned char is_wide: 1;
 };
 
 struct runes_row {