PlayStation Universe

Cell and RSX work together for best results

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A research paper published by Sony this week shows some interesting numbers produced by a technique called deferred rendering, as utilised by the PlayStation 3.

Be warned that the report is very technical and requires a good degree of understanding of how lighting and shaders work to fully grasp. It may not be for the uninitiated but if you have an interest in algorithms and unusual computing platforms then it makes for quite a good read.

The idea is that Synergistic Processing Elements (SPEs) of the Cell/BE can use the chip's DMA list feature to gather "irregular fine-grained fragments of texture data" generated by the RSX graphics chip, returning shading textures in the same way.

This means that the many small SPEs can apply shading on top of the work that the GPU does to texture the game world, shunting some of the workload to the (potentially underused) Cell/BE. The end result is that more work can be done while maintaining a high framerate.

The example code used for the research achieved an 85 Hz frame rate at 720p resolution. The report states that although numbers like that are unlikely to show up in actual games, progress has been made to at least utilise this method to improve graphics and frame rates in game.

Feel free to download the report for yourself and see what you make of it. It looks to us like the choice of such an unusual processor and memory architecture are beginning to pay off for Sony. We expect to see great things from developers as they continue to learn how to take full advantage of the hardware.