RenderEngine.ConnectFrontEnd Method

Microsoft DirectX 8.1 (C++)

RenderEngine.ConnectFrontEnd Method

The RenderEngine.ConnectFrontEnd method builds the front end of the filter graph from the current timeline.

Syntax

object.ConnectFrontEnd()

Parameters

This method takes no parameters.

Error Codes

If the method fails, an error is raised, and Err.Number can be set to one of the following values:

Value	Description
E_INVALIDARG	No timeline set for this render engine.
E_MUST_INIT_RENDERER	Render engine failed to initialize.
E_RENDER_ENGINE_IS_BROKEN	Operation failed because the project was not rendered successfully.
E_UNEXPECTED	Unexpected error.
VFW_E_INVALIDMEDIATYPE	Invalid media type.

Remarks

This method does not build the rendering portion of the filter graph. The application must connect the output pins on the front end to the desired rendering filters:

To preview, call the RenderOutputPins method.
To output a file, call GetGroupOutputPin to retrieve the output pin for each group, then connect the pins to a multiplexer filter.

If you are using the RenderEngine object, the output pins on the front end produce uncompressed data. If you are using the SmartRenderEngine object, the output pins produce compressed data.

If you change the timeline after you build the filter graph, you must call ConnectFrontEnd again to rebuild the front end. The method preserves the rendering portion of the graph whenever possible. However, if you add or delete a group, or change the order of the groups, ConnectFrontEnd deletes the rendering portion and your application must rebuild it.

See Also