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**kazzuya** · August 20th, 2001

Cool we got Lewpy and Pete involved 8)

Just for fun, some time ago I tried a new approach for a DX8 plugin. Since my TNT2 doesn't support palettized texture, my main issue was to reliably deal with dynamic palettes. My approach was then a raw power one: generate 16 bit texture pages with one rectangular sub-texture for each polygon.
Basically for every polygon I'd allocate some space in VRAM with the required texture and then render all those polygons later.
Unfortunately texture uploading isn't very fast at least when using DX8 lockrect without any kind of double buffered DMA trick.
The advantage of that were:
1) Only need one NxM texture. For example a 512x512 texture can handle up to 256 polygons if the PSX textures are about 32x32 ( (512/32) * (512/32) = 16 * 16 = 256 ).

2) Brute force palette to 16bit conversion for every polygon guarantees success with dynamic palette (fog or just a billion 16 color palettes like in Tekken 3).

3) Because every polygon's texture generated is converted from PSX RAM into a secondary destination one can afford the luxury or padding the texture margins with a little more work therefore eliminating the issues with bilinear grabbing the texels of nearby textures.

Too bad the framerate was sad..
So.. don't try that at home !

August 20th, 2001	#16 (permalink)
kazzuya Emu author Join Date: Jul 2001 Posts: 40	the plugins nightmare Cool we got Lewpy and Pete involved 8) Just for fun, some time ago I tried a new approach for a DX8 plugin. Since my TNT2 doesn't support palettized texture, my main issue was to reliably deal with dynamic palettes. My approach was then a raw power one: generate 16 bit texture pages with one rectangular sub-texture for each polygon. Basically for every polygon I'd allocate some space in VRAM with the required texture and then render all those polygons later. Unfortunately texture uploading isn't very fast at least when using DX8 lockrect without any kind of double buffered DMA trick. The advantage of that were: 1) Only need one NxM texture. For example a 512x512 texture can handle up to 256 polygons if the PSX textures are about 32x32 ( (512/32) * (512/32) = 16 * 16 = 256 ). 2) Brute force palette to 16bit conversion for every polygon guarantees success with dynamic palette (fog or just a billion 16 color palettes like in Tekken 3). 3) Because every polygon's texture generated is converted from PSX RAM into a secondary destination one can afford the luxury or padding the texture margins with a little more work therefore eliminating the issues with bilinear grabbing the texels of nearby textures. Too bad the framerate was sad.. So.. don't try that at home !