rate limit redraws

2 files changed, 45 insertions, 0 deletions

diff --git a/src/window-xlib.c b/src/window-xlib.c
index 48d8654..64abafc 100644
--- a/src/window-xlib.c
+++ b/src/window-xlib.c
@@ -1,5 +1,6 @@
 #include <cairo-xlib.h>
 #include <stdlib.h>
+#include <time.h>
 #include <unistd.h>
 #include <X11/cursorfont.h>
 #include <X11/Xlib.h>
@@ -83,6 +84,8 @@ static Bool runes_window_backend_find_flush_events(
 static void runes_window_backend_resize_window(
     RunesTerm *t, int width, int height);
 static void runes_window_backend_flush(RunesTerm *t);
+static int runes_window_backend_check_recent(RunesTerm *t);
+static void runes_window_backend_delay_cb(RunesTerm *t);
 static void runes_window_backend_visible_scroll(RunesTerm *t, int count);
 static void runes_window_backend_visual_bell(RunesTerm *t);
 static void runes_window_backend_reset_visual_bell(RunesTerm *t);
@@ -470,6 +473,10 @@ static void runes_window_backend_flush(RunesTerm *t)
 {
     RunesWindowBackend *w = &t->w;
 
+    if (runes_window_backend_check_recent(t)) {
+        return;
+    }
+
     if (t->scr.audible_bell) {
         runes_window_backend_audible_bell(t);
         t->scr.audible_bell = 0;
@@ -503,6 +510,41 @@ static void runes_window_backend_flush(RunesTerm *t)
     cairo_paint(w->backend_cr);
     runes_display_draw_cursor(t, w->backend_cr);
     cairo_surface_flush(cairo_get_target(w->backend_cr));
+
+    clock_gettime(CLOCK_REALTIME, &w->last_redraw);
+}
+
+static int runes_window_backend_check_recent(RunesTerm *t)
+{
+    RunesWindowBackend *w = &t->w;
+    struct timespec now;
+
+    clock_gettime(CLOCK_REALTIME, &now);
+    now.tv_nsec -= 10000000;
+    if (now.tv_nsec < 0) {
+        now.tv_sec -= 1;
+        now.tv_nsec += 1000000000;
+    }
+    if (now.tv_sec < w->last_redraw.tv_sec || (now.tv_sec == w->last_redraw.tv_sec && now.tv_nsec < w->last_redraw.tv_nsec)) {
+        if (!w->delaying) {
+            runes_loop_timer_set(
+                t->loop, 10, 0, t, runes_window_backend_delay_cb);
+            w->delaying = 1;
+        }
+        return 1;
+    }
+    else {
+        return 0;
+    }
+
+}
+
+static void runes_window_backend_delay_cb(RunesTerm *t)
+{
+    RunesWindowBackend *w = &t->w;
+
+    w->delaying = 0;
+    runes_window_backend_request_flush(t);
 }
 
 static void runes_window_backend_visible_scroll(RunesTerm *t, int count)
diff --git a/src/window-xlib.h b/src/window-xlib.h
index 4a49340..d8e04f2 100644
--- a/src/window-xlib.h
+++ b/src/window-xlib.h
@@ -2,6 +2,7 @@
 #define _RUNES_XLIB_H
 
 #include <cairo.h>
+#include <time.h>
 #include <X11/Xlib.h>
 
 enum runes_atoms {
@@ -27,12 +28,14 @@ struct runes_window {
     XEvent event;
     char *selection_contents;
     size_t selection_len;
+    struct timespec last_redraw;
 
     cairo_t *backend_cr;
 
     Atom atoms[RUNES_NUM_ATOMS];
 
     char visual_bell_is_ringing: 1;
+    char delaying: 1;
 };
 
 void runes_window_backend_create_window(RunesTerm *t, int argc, char *argv[]);