swaybg: implement scaling mode "fill"

1 files changed, 23 insertions, 0 deletions

diff --git a/swaybg/main.c b/swaybg/main.c
index 5510f2ef..a85c56bd 100644
--- a/swaybg/main.c
+++ b/swaybg/main.c
@@ -14,6 +14,7 @@ struct registry *registry;
 
 enum scaling_mode_t {
         SCALING_MODE_STRETCH,
+        SCALING_MODE_FILL,
 };
 
 void sway_terminate(void) {
@@ -61,6 +62,8 @@ int main(int argc, const char **argv) {
         enum scaling_mode_t scaling_mode;
         if (strcmp(scaling_mode_str, "stretch") == 0) {
                 scaling_mode = SCALING_MODE_STRETCH;
+        } else if (strcmp(scaling_mode_str, "fill") == 0) {
+                scaling_mode = SCALING_MODE_FILL;
         } else {
                 sway_abort("Unsupported scaling mode: %s", scaling_mode_str);
         }
@@ -76,6 +79,26 @@ int main(int argc, const char **argv) {
                                                         (double) window->height / height);
                                         cairo_set_source_surface(window->cairo, image, 0, 0);
                                         break;
+                                case SCALING_MODE_FILL:
+                                        {
+                                                double window_ratio = (double) window->width / window->height;
+                                                double bg_ratio = width / height;
+
+                                                if (window_ratio > bg_ratio) {
+                                                        double scale = (double) window->width / width;
+                                                        cairo_scale(window->cairo, scale, scale);
+                                                        cairo_set_source_surface(window->cairo, image,
+                                                                        0,
+                                                                        (double) window->height/2 / scale - height/2);
+                                                } else {
+                                                        double scale = (double) window->height / height;
+                                                        cairo_scale(window->cairo, scale, scale);
+                                                        cairo_set_source_surface(window->cairo, image,
+                                                                        (double) window->width/2 / scale - width/2,
+                                                                        0);
+                                                }
+                                        }
+                                        break;
                                 default:
                                         sway_abort("Scaling mode '%s' not implemented yet!", scaling_mode_str);
                         }