Thanks to pixel repacking using cpu data cache, this has a low runtime
cost even for TGL_LINEAR.
Adds support for TGL_NEAREST.
Adds support for TGL_MIRRORED_REPEAT, TGL_CLAMP_TO_EDGE and TGL_REPEAT.
Also, add support for more texture clamping and resampling options.
Mipmaps are not supported, although their sampling modes will be
applied - but to the full-size texture instead of selected mipmap.
Note: Texture sampler is still chosen at texture creation time.
I based ARGB scaling on ST scaling without giving it enough thought.
It accidentally uncovered an older bug in glopClear, which made me recheck
these formulas.
ST scaling maps [0.0, 1.0] to [0x01.0000, 0xff.0000], meaning the first and
last texture rows and columns are never shown.
Treating s and t as proportions of ST_MAX fixes this by mapping to
[0x00.0000, 0xff.fffc] (last two fractional bits being off-precision, as
there are only 14 bits), covering the whole available range.
These shifts are now handled in zline (only user of this macri),
consistently with ztriangle.
I have removed this macro from my working copy, but I missed the breakage
while resolving the conflict.
Before this change vertex data (post-shading) was limited to 6 (green) or
5 (all others) bits of precision.
Interpolation happened with 8-bits precision, so the visual effect is
minor: about 4 off at vertices.
As in ztriangle, vertex color must be shifted from internal 16-bits
fixed-point format to 8-bits colors.
To do so, define values similar to the ones describing for ST fixed-point
format.
Also, use these in tglClear instead of hard-coded multiplicands, as is
done in tglColor4f and gl_transform_to_viewport.
Also, make tglClear take into account requested clear depth.
As per Common::Rect data model, right and bottom border are excluded, so:
- Make FrameBuffer::scissorPixel reject bottom & right borders.
- Update bounding rectangle definition for dirty rectangle operations
ClearBufferDrawCall::getDirtyRegion is already correct.
- zblit was almost following, except for an off-by-one mistake.
This reverts commit b8bddf64da.
Since 9b7548ccf7, alpha test is enabled
when drawing model faces, fixing transparency issues in GRIM which were
corrected by reverted commit.
It is incorrect to test transparency when caller did not enable it.
Also, this change bypasses increments done at the end of
putPixelTextureMappingPerspective, so transparent textures in 16 bits mode
would be stuck on the transparent pixel for the current line's 8-pixel run
in filTriangle, and would ignore z coordinate.
Scissor operations happen in a 2d rectangle, but it used to take a buffer
offset as a parameter. As a result, it had to divide that value with its
width, which is an expensive operation, which has to be done for each
pixel candidate for display (even before z-buffer comparison when
applicable, in current implementatoin).
But callers actually generate the buffer offset from rectangular
coordinates, so propagate these instead.
This sadly increases API redundancy, but saves a lot of time in a very
frequent occurrence (especially when enabling dirty rect mechanism,
which is not yet enabled by default).
drawLine was broken for dx = 0 lines.
Also, the split between fillLineGeneric and drawLine, along with the many
parameters exchanged (with obscure names with subtle differences), made
the code hard to understand.
This implementation should be easier to check.
There was no visible CPU usage change.
Fixes GRIM's ticket printer, which are composed of a lot of vertical
segments.
Because writePixel may decide to not write anything (alpha test), in which
case no z-buffer write should happen.
Factorises code.
Fixes apparent back-face culling in GRIM behind transparent textures, like
the tube (the 3d-shape Manny takes out, not the flat image in foreground)
in set mo.
