The purpose is to emulate correctly destination alpha factor
An alpha channel of 128 is 1.0 in the GS but only ~0.5 in the GPU
I think few draw call use destination alpha so impact on perf must remains small.
Actually it can partially be done with GL_ARB_shader_image_load_store
extension. However all drivers that support shader_image have
texture barrier too.
The idea is to use a floating texture to accumulate the data and
then do a final postprocessing pass to apply the modulo
v2:
* use bounding box to
* fix vertex corruption issue
* use negative number in shader which allow to use half float (+12
fps@4x)
Previous CopyRect function does a memcopy without conversion.
This function will allow to use different format for input/output. Just a
possibility for the future
Basically the code does the alpha multiplication in the shader therefore
the blend unit only does a pure addition. This way the multiplication is
accurate and accurate_blending doesn't requires a costly barrier.
This code also avoid variable duplication to make the code more separated.
Hopefully blending can be done in a separated function
It is preliminary work to support fast color clipping with HDR
v2: fix assertion compilation failure
v3: fix regression in not accurate mode
v3: Cs * As/Af is not an accumulation
Those cases don't need the Cd addition and were already optimized anyway
Fix a regression on GoW2
Do DATE algo selection before blending. This way we can detect bad
interaction.
Regroup all blending/colclip in a single block. Avoid to check abe &&
rt multiple times.
v2: only enable sw blending when abe is true
The updated medium level will run for all sprites. It helps sotc blooming effect and it remains
fast enough to be enabled by default (at least on 3D games)
The new high level will run for all sprites + color clipping
The idea is that sprites are often use for post-processing effect (ofc except 2D games)
Most of the time post-processing supports SW blending with a small speed penality. SW
blending is more accurate so it is better to use it.
Sourceforge was dead for more than a week therefore add the license
information. I could not find the original TGM source (dead link) so I'm not
even sure if this still applies or if the glsl was totally rewritten. None
of the glsl files have a copyright header so it's hard to tell.
Gain: 1% at 4x on SotC (it partially compensates recent additions)
When the color is constant and equal to 128, the MODULATE mode is
equivalent to the DECAL mode. It saves 5 instructions on the FS.
Accurate options do a better jobs. Technically it can still
be useful for old gpu/driver that doesn't support the GL4.5 extension.
On Windows, you can still rely on Dx
On linux, free driver support it (except Intel)
It fixes the bad light on Silent Hill with the SW renderer.
Full story
if Q is NaN, m_vt.m_eq.q becomes wrongly true
/Q will wrongly be optimized in the "Vertex Shader" of the SW
Note: Add an assert for the STQ handler
Code path is quite hot so no need to add extra check for nothing
GS uses integer value and does integer operation too.
This commit trunc the sampled texture, the interpoled fragment color
and the product of the 2.
It impacts negatively the perf of about 3/4% (GPU) but it fixes rendering on
suikoden and potentially some others games too.
Code was completey bitrotten
Code was a partial test (and yet 500 lines already)
Shader is more and more complex and multithreading support greatly
reduce the cost of shader switch
Nvidia allows to get the ASM of the shader of the compiled shader. It is useful
to check the performance.
It also allow me to compile most of shader code path for QA
Dump is enabled in linux replayer + debug_glsl_shader = 2
Code is not yet enabled because it requires extensive test
The idea is to replace point by a 1 pixels sprite with the help of
a geometry shader. In 4x, point will be replaced by a 4x4 sprite.
Partially invalidate RT when there is a write in the middle of it (actually 2 pages below)
Code is not yet enabled because
1/ I want to stabilize latest update
2/ not sure of the impact of the code
3/ maybe it need a more generic version
Frame is always 32 bits but game can reuse it later as a 16 bits RT.
Fix half screen issue with Ricky Ponting Cricket
Unfortunately it triggers texture shuffle wrongly. I hope there is no
regression.
Fix depth issue.
First issue: RT and Depth are located at the same address.
=> solution, just lookup the depth (done for any games)
Second issue: Instead to draw a X,Y rectangle, they draw a 32 pix, 4096 pix
rectangle with a FBW of 1.
=> solution, don't bother just write the depth directly
Please someone add some CRC to enable the code
// GL42 interact very badly with sw blending. GL42 uses the primitiveID to find the primitive
// that write the bad alpha value. Sw blending will force the draw to run primitive by primitive
// (therefore primitiveID will be constant to 1)
It is mostly the texture shuffle effect which is now emulated correctly on openGL
They remain in the Dx level as speedhack in particular for
* Castlevania;
* GodOfWar;
* StarOcean3;
* ValkyrieProfile2;
* RadiataStories;
Remove old commented hack: Drakengard2, ArctheLad, ReZ
Separate hacks that are only enabled in aggressive mode
It might save a couple of fps
Add a define to test the perf if we keep only the blue channel. It brokes
the code in Prince Of Persia that use the Red/Green channel... Maybe the
speed hack :( Or find a way to replace all if with a lookup table
Note: it is only supported on OpenGL currently
Code unscale the texture to ease the conversion. Quality is awful (same as before)
but I'm not sure we can support an upscaled texture
Maybe the quality loss is due to the reduction without mipmap
Maybe the best solution will be to add an hack to extract the blue channel
(with texture swizzle), and uses a "full page/screen" spirte instead.
(it would be faster too)
Note: won't be compatible with MSAA (but gl doesn't support it anyway)
// In theory new textures contain invalidated data. Still in theory a new target
// must contains the content of the GS memory.
// In practice, TC will wrongly invalidate some RT. For example due to write on the alpha
// channel but colors is still valid. Unfortunately TC doesn't support the upload of data
// in target.
//
// Cleaning the code here will likely break several games. However it might reduce
// the noise in draw call debugging. It is the main reason to enable it on debug build.
//
// From a performance point of view, it might cost a little on big upscaling
// but normally few RT are miss so it must remain reasonable.
Game can directly uploads a background or the full image in
"CTRC" buffer. Previous code was a full black screen.
It will also avoid various black screen issue in gs dump.
hidden option: preload_frame_with_gs_data
Note: impact on upscaling was not tested and it's likely broken
Improve the rendering in MGS3 (even if the game is still broken
due to others TC issues)
// Typical bug (MGS3 blue cloud):
// 1/ RT used as 32 bits => alpha channel written
// 2/ RT used as 24 bits => no update of alpha channel
// 3/ Lookup of texture that used alpha channel as index, HasSharedBits will return false
// because of the previous draw call format
//
// Solution: consider the RT as 32 bits if the alpha was used in the past
"Regression" introduced in 8 bits RT support
The case appears when
1/ address of RT is the same as input texture
2/ input format is 8 bits
3/ previous lookup of RT was miss
It avoid various upscaling glitches on GS post-processing effect
// 1/ Palette is used to interpret the alpha channel of the RT as an index.
// Star Ocean 3 uses it to emulate a stencil buffer.
// 2/ Z formats are a bad idea to interpolate (discontinuties).
// 3/ 16 bits buffer is used to move data from a channel to another.
//
// I keep linear filtering for standard color even if I'm not sure that it is
// working correctly.
// Indeed, texture is reduced so you need to read all covered pixels (9 in 3x)
// to correctly interpolate the value. Linear interpolation is likely acceptable
// only in 2x scaling
//
// Src texture will still be bilinear interpolated so I'm really not sure
// that we need to do it here too.
//
// Future note: instead to do
// RT 2048x2048 -> T 1024x1024 -> RT 2048x2048
// We can maybe sample directly a bigger texture
// RT 2048x2048 -> T 2048x2048 -> RT 2048x2048
// Pro: better quality. Copy instead of StretchRect (must be faster)
// Cons: consume more memory
//
// In distant future: investigate to reuse the RT directly without any
// copy. Likely a speed boost and memory usage reduction.
It might help to fix a bit the color on a couple of games
accurate_fbmask = 1
Code uses GL4.5 extensions. So far it seems the effect is ony used a couple
of time and often in non-overlapping primitive. Speed impact will likely remain small
It seems to impacts lots of games that still have issue (VP2, MTG3, PoP)
The PSMT32 format is read a PSMT8. I think we need to convert it as PSMT8H (i.e.
unpack it to have only an alpha channel)
Gregory Hainaut