[Bug 19471] Earthworm Jim 3D: Extensive graphics errors

[WineHQ Bugzilla]

https://bugs.winehq.org/show_bug.cgi?id=19471

Paul Gofman <gofmanp at gmail.com> changed:

           What    |Removed                     |Added
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                 CC|                            |gofmanp at gmail.com

--- Comment #18 from Paul Gofman <gofmanp at gmail.com> ---
Created attachment 65756
  --> https://bugs.winehq.org/attachment.cgi?id=65756
Fixes

I've tested the game, observed three issues described in Comment #13, and found
three distinct reasons for them. I am attaching the patch which actually
consists of three and contains proof of concept fixes.

1. Missing text
    The game renders text by preparing a set of textures each containing a
letter and then drawing those textures. The problem happens at the texture
preparation stage.
 The textures have _B4G4R4A4 format. Application creates temporary surface (of
_B5G5R5A1 format), uses IDirectDrawSurface4_GetDC() to get surface's DC, and
then doing SetTextColor(dc, 0xffffffff), DrawTextA(...). After that the
application creates _B4G4R4A4 surface, locks both and sets the new surface data
looking at alpha component of original surface samples. The problem is that gdi
draws the text with color 0. This originates from get_pixel_color() returning 0
color (gdi32/dibdrv/objects). The color stored in context is correct, but
make_rgb_colorref() decides that color is palette index and returns 0. The fix
in the attached patch fixes the problem in the game, but the fix is likely
wrong, I did not test that much enough. I can guess the correct decision on
whether to ignore palette flags check likely has something to do with the DIB
having alpha channel rather than with the color value itself.

2. Missing elements in the introduction screens.
    The game is using _SetViewport2() to set the viewport in the beginnig, gets
another viewport back with _GetViewport() and using the values from it for
vertex transformation. Dividing into 0 ScaleX, ScaleY eventually leads to NaNs
in vertex positions. It looks like native ddraw does some conversion. The
attached patch contains a fix with a basic test.

3. Dark or missing elements in game
    The game creates some number of DXT1 and DXT3 mipmapped textures and
initializes the most detailed level. It then uses _Blt() to stretch the data
for each next mip level using a previous one. This requires our CPU blitter to
be able to stretch between compressed format. I am attaching a very quick
implementation which fixes the rendering, while it is really a draft and has
not been tested much.

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