/vr/ - Retro Games

>>7435478
The Gamecube's GPU can use S3TC's compressed textures which provides for a 6:1 ratio in compression for 24-bit textures. For 16-bit textures the ratio is 4:1, and for 8-bit textures the ratio is 2:1.

Let us consider how much compressed textures the Gamecube can hold in it's 24 MB of main memory if we consider different memory size requirements for game code/geometry/etc.
Code/Geometry/etc. Free Texture Space 24-bit Textures (compressed 6:1)
6 MB 18 MB 108 MB
8 MB 16 MB 96 MB
10 MB 14 MB 84 MB
12 MB 12 MB 72 MB


As you can see the Gamecube can store lots of textures in it's memory using S3TC's texture compression format. Note that another benefit of using compressed textures is that the bandwidth requirements also decrease by the same ratio as the actual compression. At a ratio of 6:1, the memory bus can pass 6 times more textures. That means the GPU's texture cache bus of 10.4 GB/sec can pass 62.4 GB of 24-bit compressed textures, and the external bus of 2.6 GB/sec can pass 15.6 GB of 24-bit compressed textures each second!