1 files changed, 24 insertions, 4 deletions

diff --git a/src/backend/dummy/dummy.c b/src/backend/dummy/dummy.c
index a057b97..7e06fac 100644
--- a/src/backend/dummy/dummy.c
+++ b/src/backend/dummy/dummy.c
@@ -23,6 +23,8 @@ struct dummy_image {
 struct dummy_data {
 	struct backend_base base;
 	struct dummy_image *images;
+
+	struct backend_image mask;
 };
 
 struct backend_base *dummy_init(struct session *ps attr_unused) {
@@ -47,6 +49,9 @@ void dummy_deinit(struct backend_base *data) {
 
 static void dummy_check_image(struct backend_base *base, const struct dummy_image *img) {
 	auto dummy = (struct dummy_data *)base;
+	if (img == (struct dummy_image *)&dummy->mask) {
+		return;
+	}
 	struct dummy_image *tmp = NULL;
 	HASH_FIND_INT(dummy->images, &img->pixmap, tmp);
 	if (!tmp) {
@@ -56,10 +61,13 @@ static void dummy_check_image(struct backend_base *base, const struct dummy_imag
 	assert(*tmp->refcount > 0);
 }
 
-void dummy_compose(struct backend_base *base, void *image, int dst_x1 attr_unused,
-                   int dst_y1 attr_unused, int dst_x2 attr_unused, int dst_y2 attr_unused,
-		   const region_t *reg_paint attr_unused, const region_t *reg_visible attr_unused) {
+void dummy_compose(struct backend_base *base, void *image, coord_t dst attr_unused,
+                   void *mask attr_unused, coord_t mask_dst attr_unused,
+                   const region_t *reg_paint attr_unused,
+                   const region_t *reg_visible attr_unused) {
+	auto dummy attr_unused = (struct dummy_data *)base;
 	dummy_check_image(base, image);
+	assert(mask == NULL || mask == &dummy->mask);
 }
 
 void dummy_fill(struct backend_base *backend_data attr_unused, struct color c attr_unused,
@@ -67,7 +75,8 @@ void dummy_fill(struct backend_base *backend_data attr_unused, struct color c at
 }
 
 bool dummy_blur(struct backend_base *backend_data attr_unused, double opacity attr_unused,
-                void *blur_ctx attr_unused, const region_t *reg_blur attr_unused,
+                void *blur_ctx attr_unused, void *mask attr_unused,
+                coord_t mask_dst attr_unused, const region_t *reg_blur attr_unused,
                 const region_t *reg_visible attr_unused) {
 	return true;
 }
@@ -94,6 +103,9 @@ void *dummy_bind_pixmap(struct backend_base *base, xcb_pixmap_t pixmap,
 
 void dummy_release_image(backend_t *base, void *image) {
 	auto dummy = (struct dummy_data *)base;
+	if (image == &dummy->mask) {
+		return;
+	}
 	auto img = (struct dummy_image *)image;
 	assert(*img->refcount > 0);
 	(*img->refcount)--;
@@ -121,6 +133,11 @@ bool dummy_image_op(struct backend_base *base, enum image_operations op attr_unu
 	return true;
 }
 
+void *dummy_make_mask(struct backend_base *base, geometry_t size attr_unused,
+                      const region_t *reg attr_unused) {
+	return &(((struct dummy_data *)base)->mask);
+}
+
 bool dummy_set_image_property(struct backend_base *base, enum image_properties prop attr_unused,
                               void *image, void *arg attr_unused) {
 	dummy_check_image(base, image);
@@ -158,7 +175,10 @@ struct backend_operations dummy_ops = {
     .fill = dummy_fill,
     .blur = dummy_blur,
     .bind_pixmap = dummy_bind_pixmap,
+    .create_shadow_context = default_create_shadow_context,
+    .destroy_shadow_context = default_destroy_shadow_context,
     .render_shadow = default_backend_render_shadow,
+    .make_mask = dummy_make_mask,
     .release_image = dummy_release_image,
     .is_image_transparent = dummy_is_image_transparent,
     .buffer_age = dummy_buffer_age,