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Revision as of 19:47, 29 May 2019


Hollywood is the name of the graphics chip (GPU) used in the Nintendo Wii. It was designed by ATI (now AMD), and was manufactured using the same 90nm process as the Broadway CPU. Hollywood is a direct evolution of Flipper, the GPU used in the Wii's predecessor, the GameCube; in fact, the two GPUs are fundamentally identical. They are very similarly capable, with the Wii's GPU being clocked 50% faster (243MHz, as opposed to Flipper at 162MHz) with the same memory pool (3.1MB). Hollywood provides no improvements in programmability compared to Flipper, however the benefit of this similarity between the two chips is that Hollywood is completely backwards compatible with Flipper.

Hollywood comes with the addition of an ARM chip, nicknamed "Starlet", which is clocked at the same speed as the graphics chip (243MHz). Starlet handles I/O, wireless and security functionality among other things, and is responsible for the running of the Wii's IOS (internal operating system). Effectively, Starlet is the only meaningful difference between Hollywood and Flipper.

Hardware Capabilities

  • 243MHz graphics chip
  • 3.1MB GPU memory (for textures and buffers) - can directly access nearby 24MB of 1T-SRAM
  • Nearby, directly accessible 24MB 1T-SRAM @ 486MHz (3.9GB/s)
  • Fixed function pipeline (no support for programmable vertex or pixel shaders in hardware)
  • Texture Environment Unit (TEV) - capable of combining up to 8 textures in up to 16 stages or "passes"
  • 30-37.5GB/s internal bandwidth (speculation: confirmed AMD GameCube data x 1.5)
  • 18 million polygons/second

Texture Environment Unit

The Texture Environment Unit (TEV) is a unique piece of hardware exclusive to the GameCube and Wii. The Wii inherited the TEV from Flipper, and the TEV is - to use an analogy from Factor 5 director Julian Eggebrecht - "like an elaborate switchboard that makes the wildest combinations of textures and materials possible."

The TEV pipeline combines up to 8 textures in up to 16 stages at once. Each stage can apply a multitude of functions to the texture. This was frequently used to simulate pixel shader effects such as bump-mapping, or to perform effects such as cel shading. The TEV pipeline is completely under programmer control; as a result, the more time the developer puts in to write effects in software, the better results they will get. On the GameCube, Factor 5's Star Wars: Rogue Squadron II used the TEV for the targeting computer effect and the simulated volumetric fog. In another scenario, Wave Race: Blue Storm used the TEV notably for water distortion (such as refraction) and other water effects. The Wii's TEV unit and TEV capabilities are no different from the GameCube's, excluding indirect performance advantages from the faster clock speeds.