From fd25018cdd423f1a2fe4c87d607903ac40a8cedd Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Ekl=C3=B6f?= <daniel@ekloef.se>
Date: Fri, 5 Jul 2019 15:53:53 +0200
Subject: [PATCH] render: fill area outside the cell grid with default bg color

---
 render.c | 22 ++++++++++++++++++++--
 1 file changed, 20 insertions(+), 2 deletions(-)

diff --git a/render.c b/render.c
index 38fa4d86..6f70309b 100644
--- a/render.c
+++ b/render.c
@@ -369,7 +369,26 @@ grid_render(struct terminal *term)
         if (last_buf != NULL) {
             LOG_WARN("new buffer");
 
-            /* Force a full refresh */
+            /* Fill area outside the cell grid with the default background color */
+            int rmargin = term->cols * term->cell_width;
+            int bmargin = term->rows * term->cell_height;
+            int rmargin_width = term->width - rmargin;
+            int bmargin_height = term->height - bmargin;
+
+            cairo_set_source_rgba(
+                buf->cairo, term->background.r, term->background.g,
+                term->background.b, term->background.a);
+
+            cairo_rectangle(buf->cairo, rmargin, 0, rmargin_width, term->height);
+            cairo_rectangle(buf->cairo, 0, bmargin, term->width, bmargin_height);
+            cairo_fill(buf->cairo);
+
+            wl_surface_damage_buffer(
+                term->wl.surface, rmargin, 0, rmargin_width, term->height);
+            wl_surface_damage_buffer(
+                term->wl.surface, 0, bmargin, term->width, bmargin_height);
+
+            /* Force a full grid refresh */
             term_damage_all(term);
         }
         last_buf = buf;
@@ -553,7 +572,6 @@ render_update_cursor_surface(struct terminal *term)
         term->wl.pointer.surface,
         image->hotspot_x / scale, image->hotspot_y / scale);
 
-
     wl_surface_damage_buffer(
         term->wl.pointer.surface, 0, 0, INT32_MAX, INT32_MAX);