scene: add wlr_scene_buffer_set_transform

include/wlr/types/wlr_scene.h

@@ -96,6 +96,7 @@ struct wlr_scene_buffer {
 	struct wlr_texture *texture;
 	struct wlr_fbox src_box;
 	int dst_width, dst_height;
+	enum wl_output_transform transform;
 };
 
 /** A viewport for an output in the scene-graph */
@@ -232,6 +233,12 @@ void wlr_scene_buffer_set_source_box(struct wlr_scene_buffer *scene_buffer,
 void wlr_scene_buffer_set_dest_size(struct wlr_scene_buffer *scene_buffer,
 	int width, int height);
 
+/**
+ * Set a transform which will be applied to the buffer.
+ */
+void wlr_scene_buffer_set_transform(struct wlr_scene_buffer *scene_buffer,
+	enum wl_output_transform transform);
+
 /**
  * Add a viewport for the specified output to the scene-graph.
  *

types/scene/wlr_scene.c

@@ -295,6 +295,17 @@ void wlr_scene_buffer_set_dest_size(struct wlr_scene_buffer *scene_buffer,
 	scene_node_damage_whole(&scene_buffer->node);
 }
 
+void wlr_scene_buffer_set_transform(struct wlr_scene_buffer *scene_buffer,
+		enum wl_output_transform transform) {
+	if (scene_buffer->transform == transform) {
+		return;
+	}
+
+	scene_node_damage_whole(&scene_buffer->node);
+	scene_buffer->transform = transform;
+	scene_node_damage_whole(&scene_buffer->node);
+}
+
 static struct wlr_texture *scene_buffer_get_texture(
 		struct wlr_scene_buffer *scene_buffer, struct wlr_renderer *renderer) {
 	struct wlr_client_buffer *client_buffer =
@@ -337,10 +348,15 @@ static void scene_node_get_size(struct wlr_scene_node *node,
 		if (scene_buffer->dst_width > 0 && scene_buffer->dst_height > 0) {
 			*width = scene_buffer->dst_width;
 			*height = scene_buffer->dst_height;
+		} else {
+			if (scene_buffer->transform & WL_OUTPUT_TRANSFORM_90) {
+				*height = scene_buffer->buffer->width;
+				*width = scene_buffer->buffer->height;
 			} else {
 				*width = scene_buffer->buffer->width;
 				*height = scene_buffer->buffer->height;
 			}
+		}
 		break;
 	}
 }
@@ -658,6 +674,7 @@ static void render_node_iterator(struct wlr_scene_node *node,
 
 	struct wlr_texture *texture;
 	float matrix[9];
+	enum wl_output_transform transform;
 	switch (node->type) {
 	case WLR_SCENE_NODE_ROOT:
 	case WLR_SCENE_NODE_TREE:
@@ -672,8 +689,7 @@ static void render_node_iterator(struct wlr_scene_node *node,
 			return;
 		}
 
-		enum wl_output_transform transform =
-			wlr_output_transform_invert(surface->current.transform);
+		transform = wlr_output_transform_invert(surface->current.transform);
 		wlr_matrix_project_box(matrix, &dst_box, transform, 0.0,
 			output->transform_matrix);
 
@@ -694,7 +710,8 @@ static void render_node_iterator(struct wlr_scene_node *node,
 			return;
 		}
 
-		wlr_matrix_project_box(matrix, &dst_box, WL_OUTPUT_TRANSFORM_NORMAL, 0.0,
+		transform = wlr_output_transform_invert(scene_buffer->transform);
+		wlr_matrix_project_box(matrix, &dst_box, transform, 0.0,
 			output->transform_matrix);
 
 		render_texture(output, output_damage, texture, &scene_buffer->src_box,