render/texture: introduce wlr_texture_invalidate

include/render/wlr_texture.h

@@ -0,0 +1,21 @@
+#ifndef RENDER_WLR_TEXTURE_H
+#define RENDER_WLR_TEXTURE_H
+
+#include <wlr/render/wlr_texture.h>
+
+/**
+ * Refresh the texture contents from the underlying buffer storage.
+ *
+ * If the texture refers to external memory (i.e. memory owned by another
+ * process), the renderer may need a wlr_texture_invalidate call to make
+ * external changes visible to the texture.
+ *
+ * This operation must not perform any copy.
+ *
+ * If the texture cannot be invalidated, false is returned. If the texture
+ * doesn't need to be invalidated for external changes to be visible, true is
+ * immediately returned.
+ */
+bool wlr_texture_invalidate(struct wlr_texture *texture);
+
+#endif

include/wlr/render/interface.h

@@ -67,6 +67,7 @@ struct wlr_texture_impl {
 		uint32_t stride, uint32_t width, uint32_t height,
 		uint32_t src_x, uint32_t src_y, uint32_t dst_x, uint32_t dst_y,
 		const void *data);
+	bool (*invalidate)(struct wlr_texture *texture);
 	void (*destroy)(struct wlr_texture *texture);
 };
 

render/wlr_texture.c

@@ -3,6 +3,7 @@
 #include <stdlib.h>
 #include <wlr/render/interface.h>
 #include <wlr/render/wlr_texture.h>
+#include "render/wlr_texture.h"
 
 void wlr_texture_init(struct wlr_texture *texture,
 		const struct wlr_texture_impl *impl, uint32_t width, uint32_t height) {
@@ -69,3 +70,10 @@ bool wlr_texture_write_pixels(struct wlr_texture *texture,
 	return texture->impl->write_pixels(texture, stride, width, height,
 		src_x, src_y, dst_x, dst_y, data);
 }
+
+bool wlr_texture_invalidate(struct wlr_texture *texture) {
+	if (!texture->impl->invalidate) {
+		return false;
+	}
+	return texture->impl->invalidate(texture);
+}