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As I'm reading VideoCoreIV-AG100-R spec of BCM vc4 chip, there is a paragraph talking about:

All rendering by the 3D system is in tiles, requiring separate binning and rendering passes to render a frame. In normal operation the host processor creates a control list in memory defining all the operations and supplying all the data for rendering for a complete frame.

It mentions of rendering a frame requires binning and rendering pass. Could anybody explain in details how exactly those 2 passes playing roles in a graphic pipeline? Thanks a lot.

Bill Randerson
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1 Answers1

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For tile based render architecture passes are:

Binning pass - generates stream\map between frame tiles & corresponding geometry which should be rendered into particular tile

Rendering pass - takes map between tiles & geometry and renders the appropriate pixels per tile.

In mobile GPUs due to many limitations compared to Desktops GPUs (such as memory bandwidth due to in mobile devices memory is shared between GPU & CPU,etc) vendors uses approaches to split work into small pieces to decrease overall memory bandwidth consumption - for ex. apply Tile Based Rendering - to achieve efficient utilization of all available resources and gain acceptable performance.

Details

Tile Based Rendering approach described on many GPU vendors sites such as:

A look at the PowerVR graphics architecture: Tile-based rendering

GPU Framebuffer Memory: Understanding Tiling

N0dGrand87
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