A GPU based renderer for the web.
It serves as an experimental render backend for Servo, but it can also be used as such in a standalone application.
WebRender currently depends on FreeType
The main entry point to WebRender is the
Renderer::new(...) you get a
Renderer, as well as a
Renderer is responsible to render the previously processed frames onto the screen.
yourRenderApiSender.create_api(), you'll get a
which is responsible for managing resources and documents. A worker thread is used internally
to untie the workload from the application thread and therefore be able to make better use of
What is referred to as a
frame, is the current geometry on the screen.
A new Frame is created by calling
set_display_list() on the
When the geometry is processed, the application will be informed via a
a callback which you employ with set_render_notifier on the
More information about stacking contexts.
set_display_list() also needs to be supplied with
These are obtained by finalizing a
DisplayListBuilder. These are used to draw your geometry.
But it doesn't only contain trivial geometry, it can also store another StackingContext, as
The data that an external client should provide about an external image. The timestamp is used to test if the renderer should upload new texture data this frame. For instance, if providing video frames, the application could call wr.render() whenever a new video frame is ready. If the callback increments the returned timestamp for a given image, the renderer will know to re-upload the image data to the GPU. Note that the UV coords are supplied in texel-space!
The renderer is responsible for submitting to the GPU the work prepared by the RenderBackend.
Allows callers to hook into the main render_backend loop and provide additional frame ops for generate_frame transactions. These functions are all called from the render backend thread.
The interfaces that an application can implement to support providing external image buffers. When the the application passes an external image to WR, it should kepp that external image life time. People could check the epoch id in RenderNotifier at the client side to make sure that the external image is not used by WR. Then, do the clean up for that external image.
Allows callers to receive a texture with the contents of a specific pipeline copied to it. Lock should return the native texture handle and the size of the texture. Unlock will only be called if the lock() call succeeds, when WR has issued the GL commands to copy the output to the texture handle.
The interfaces that an application can implement to handle ProgramCache update
Allows callers to hook in at certain points of the async scene build. These functions are all called from the scene builder thread.