+ void draw_device_buffer(safe_ptr<device_buffer>& draw_buffer, std::shared_ptr<device_buffer>&& source_buffer, blend_mode::type blend_mode = blend_mode::normal)\r
+ {\r
+ if(!source_buffer)\r
+ return;\r
+\r
+ draw_params draw_params;\r
+ draw_params.pix_desc.pix_fmt = pixel_format::bgra;\r
+ draw_params.pix_desc.planes = list_of(pixel_format_desc::plane(source_buffer->width(), source_buffer->height(), 4));\r
+ draw_params.textures = list_of(source_buffer);\r
+ draw_params.transform = frame_transform();\r
+ draw_params.blend_mode = blend_mode;\r
+ draw_params.background = draw_buffer;\r
+\r
+ kernel_.draw(channel_.ogl(), std::move(draw_params));\r
+ }\r
+ \r
+ safe_ptr<device_buffer> create_device_buffer(size_t stride)\r
+ {\r
+ auto buffer = channel_.ogl().create_device_buffer(channel_.get_format_desc().width, channel_.get_format_desc().height, stride);\r
+ channel_.ogl().clear(*buffer);\r
+ return buffer;\r
+ }\r
+};\r
+ \r
+struct image_mixer::implementation : boost::noncopyable\r
+{ \r
+ ogl_device& ogl_;\r
+ image_renderer renderer_;\r
+ std::vector<frame_transform> transform_stack_;\r
+ std::vector<layer> layers_; // layer/stream/items\r
+public:\r
+ implementation(video_channel_context& video_channel) \r
+ : ogl_(video_channel.ogl())\r
+ , renderer_(video_channel)\r
+ , transform_stack_(1) \r
+ {\r
+ }\r