Merge pull request #21045 from karroffel/black-bar-fixes

[gles2] fix black bar artifacts

drivers/gles2/rasterizer_canvas_gles2.cpp

@@ -75,6 +75,7 @@ void RasterizerCanvasGLES2::canvas_begin() {
 	}
 
 	if (storage->frame.clear_request) {
+		glColorMask(true, true, true, true);
 		glClearColor(storage->frame.clear_request_color.r,
 				storage->frame.clear_request_color.g,
 				storage->frame.clear_request_color.b,

drivers/gles2/rasterizer_gles2.cpp

@@ -392,6 +392,12 @@ void RasterizerGLES2::end_frame(bool p_swap_buffers) {
 		OS::get_singleton()->swap_buffers();
 	else
 		glFinish();
+
+	if (p_swap_buffers) {
+		glColorMask(true, true, true, true);
+		glClearColor(0, 0, 0, 1);
+		glClear(GL_COLOR_BUFFER_BIT);
+	}
 }
 
 void RasterizerGLES2::finalize() {

drivers/gles2/rasterizer_storage_gles2.cpp

@@ -3641,6 +3641,7 @@ void RasterizerStorageGLES2::_render_target_allocate(RenderTarget *rt) {
 
 	texture_set_flags(rt->texture, texture->flags);
 
+	glClearColor(0, 0, 0, 0);
 	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 
 	// copy texscreen buffers