CyberVision 64/3D + P96 and Gears 3D demo

[ShK]

Has anyone got the Gears demo working with CV3D on Picasso96?

For me both demos, gears_68k and gears_ppc does not have a correct color.

Picasso96 or Warp3D versions seems not to affect to it. Also, WB3.1 and 3.2 looks same (clean installs).

This same happens with the real Amiga 4000/CSPPC and on WinUAE with the corresponding settings.

I have tried different WarpUP, Warp3D and P96 settings, but nothing seems to fix this.

[ShK]

Hmm... seems to do same also with the CGX. That's a real Amiga 4000/CSPPC.

[Thomas Richter]

Originally Posted by ShK

For me both demos, gears

Wrong aperture. Choose a different color mode for the workbench, so for example, try the 16 bit PC and non-PC modes.

[ShK]

Ah, thanks for the hint! It needed 15-bit color mode which e.g. Voodoo3 does not have.

[ShK]

With CGX there is only possible hide or unhide 15-bit modes, but it does not tell is it 15bit PC or non-PC mode.

What is a difference between PC and non-PC modes in this case? Which mode should we use?

[derSammler]

PC mode should be RGB, whereas non-PC should be BGR. Color channels are swapped. An Intel vs. Motorola byte order thing, I assume.

[ShK]

In our case (Warp3D), does the host computer CPU Byte Order matter when selecting between PC and non-PC mode for graphic card screen mode?

Endianness in PC Architecture (Intel x86): Little-Endian

In the context of personal computers (PCs), especially those using Intel x86 architecture, the little-endian format is predominantly used. Here, the least significant byte (LSB) of a word is stored in the smallest address, and the most significant byte (MSB) is stored in the largest address.

Endianness in Non-PC Architectures (e.g., Motorola PowerPC, 68k Architecture): Big-Endian

Non-PC architectures, like those used in some older Macintosh computers (with Motorola processors) or certain game consoles, often used the big-endian format. In big-endian, the MSB is stored in the smallest address, and the LSB is in the largest address.

[derSammler]

No, it only matters what the software expects when working in video memory directly.