86Box with PowerVR PCX2 emulation 0.2.1

Fixes resolutions above 640x480. In 0.2 every 800x600 frame failed to draw
("malformed tile list" in the log): tiles below line 512 were misread.

Compared against a real Matrox m3D at 800x600 (the X demo) and 1024x768 (GLQuake):
both exact over the whole frame. Every screen size from 320x200 to 1024x768 now
matches the card.

Full compatibility list:
https://github.com/z2k-retro/powervr-pcx2-tools/blob/main/docs/using-86box.md

Hardware, testing and direction by Z2k Retro. Written with substantial help from Claude,
Anthropic's AI model; every result was checked on the real card.

86Box with PowerVR PCX2 emulation 0.2

Changes since 0.1.1:

• Triangles whose edge lies a fraction of a pixel outside the screen are now dropped,
  as the real card does. Found with Shadows of the Empire 1.1 at 320x240 and
  320x200, where stray triangles appeared in the menus.

Since 0.1 the emulation has been compared against a real Matrox m3D on about 30 titles
and demos, including Flight Unlimited, World Cup 98, Forsaken, GLQuake, the Tomb Raider
DOS demo and Moto Racer at five resolutions; every frame matches to within a handful of
pixels. The full list:
https://github.com/z2k-retro/powervr-pcx2-tools/blob/main/docs/using-86box.md

Notes:

• Shadows of the Empire - LucasArts' 1.1 update fixes transparency glitches on PowerVR cards. Fog is missing on
  the PCX2 even then; LucasArts' own notes say so.
• With a Matrox Millennium as the 2D card, 320-wide screen modes look doubled side by
  side. That is 86Box's Millennium display; the S3 Trio64 shows them correctly.

Hardware, testing and direction by Z2k Retro. Written with substantial help from Claude,
Anthropic's AI model; every result was checked on the real card.

86Box with PowerVR PCX2 emulation 0.1.1

A small update to 0.1.

• Bilinear filtering on textures mirrored in u now matches the real m3D (measured on the card).
• Frame dumps now work with the DOS SGL driver used by Tomb Raider.
• MechWarrior 2 (the Windows 95 PowerVR version) runs.

On a Core Ultra 270K, an emulated Pentium II 450 runs these games at full speed.

Setup, settings, speed and compatibility:
https://github.com/z2k-retro/powervr-pcx2-tools/blob/main/docs/using-86box.md

Downloads (attached below once the build finishes):

• 86Box-PowerVR-Windows-64-….zip: the normal build
• 86Box-PowerVR-devsettings-Windows-64-….zip: adds developer and test settings

Use with the 86Box ROM set (https://github.com/86Box/roms). This is a test build, not part
of official 86Box; please report problems at
https://github.com/z2k-retro/powervr-pcx2-tools/issues

Known limits: render time is fixed at 7.6 ms per frame, PCX1 boards (Apocalypse 3D) are not
emulated, and bilinear filtering on textures mirrored in v can differ slightly from the card.

Hardware, testing and direction by Z2k Retro. The emulation, tools and documentation were
written with substantial help from Claude, Anthropic's AI model; every result listed above
was checked on the real card.

86Box with PowerVR PCX2 emulation 0.1

First test release of 86Box with an emulated PowerVR PCX2 (Matrox m3D) card.

It runs the real Matrox m3D drivers (tested with the retail 4.1.1 driver) as a second
graphics card beside the emulated 2D card. Frames from Moto Racer, Shadows of the Empire,
Ultim@te Race, Quake, Unreal and MDK were drawn on a real m3D and compared pixel by pixel;
every one matches to within 13 of 307,200 pixels, and most exactly.

Setup, settings, speed and compatibility:
https://github.com/z2k-retro/powervr-pcx2-tools/blob/main/docs/using-86box.md

Downloads (attached below once the build finishes):

• 86Box-PowerVR-Windows-64-….zip: the normal build
• 86Box-PowerVR-devsettings-Windows-64-….zip: adds developer and test settings

Use with the 86Box ROM set (https://github.com/86Box/roms). This is a test build, not part
of official 86Box; please report problems at
https://github.com/z2k-retro/powervr-pcx2-tools/issues

Known limits: render time is fixed at 7.6 ms per frame, PCX1 boards (Apocalypse 3D) are not
emulated, and MechWarrior 2 is untested.

Hardware, testing and direction by Z2k Retro. The emulation, tools and documentation were
written with substantial help from Claude, Anthropic's AI model; every result listed above
was checked on the real card.