FullOn3D heeft een artikel gebakken over de 22-bit rendering van de Voodoo2/3/Banshee. 3Dfx gebruikt het als excuus voor de lage maximale kleurdiepte van z'n Voodoo planken door te beweren dat de 16-bits van de Voodoo eigenlijk toch echt 22-bit is. FullOn3D gaat behoorlijk diep in op de stuff. Hier een hap uit de intro:
I don’t want to start on a negative point because I understand totally where Gary is coming from, but I do think that his JPEG comparison is a little suspect. It doesn’t really matter how small a compressed JPEG image is, it will still require more than 16-bit color depth if the final image is to contain more than 65K colors. Of course many images don’t actually require more than 65,536 unique colors and this is where palletising comes into play, however, we are talking here about 'frame-buffer' bit-depth not 'texture' bit-depth and we mustn’t get confused between the two. The RamDAC on a graphics card reads the data from the frame-buffer as RGB information (not palletised) and for 3dfx products that’s in 565 representation; i.e. 5-bits for red & blue and 6 for green (5+6+5=16 bits of color). So what is this pseudo 22-bit color all about? Well it’s all to do with 'dithering'.
De rest is hier.
