reactos/dll/opengl/mesa/blend.c
Jérôme Gardou 5f2bebf7a5 [OPENGL32][MESA] Downgrade Mesa library to version 2.6
With this commit, we now use a forked version of MESA which only supports OpenGL 1.1, like the windows implementation does.
It exposes :
  - The same pixel formats
  - The same set of extensions
  - Nothing more
All of this without taking 10% of your build time.
If you need a more modern option, look at the MESA package from Rapps, which is (and must be) maintained outside of this code tree.
CORE-7499
2019-01-19 14:23:54 +01:00

547 lines
14 KiB
C

/* $Id: blend.c,v 1.10 1998/01/27 03:42:40 brianp Exp $ */
/*
* Mesa 3-D graphics library
* Version: 2.6
* Copyright (C) 1995-1997 Brian Paul
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the Free
* Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
/*
* $Log: blend.c,v $
* Revision 1.10 1998/01/27 03:42:40 brianp
* optimized more blending modes (Kai Schuetz)
*
* Revision 1.9 1997/07/24 01:24:45 brianp
* changed precompiled header symbol from PCH to PC_HEADER
*
* Revision 1.8 1997/05/28 03:23:48 brianp
* added precompiled header (PCH) support
*
* Revision 1.7 1997/04/20 19:51:57 brianp
* replaced abort() with gl_problem()
*
* Revision 1.6 1997/02/15 18:27:56 brianp
* fixed a few error messages
*
* Revision 1.5 1997/01/28 22:17:19 brianp
* moved logic op blending into logic.c
*
* Revision 1.4 1997/01/04 00:13:11 brianp
* was using ! instead of ~ to invert pixel bits (ugh!)
*
* Revision 1.3 1996/09/19 00:53:31 brianp
* added missing returns after some gl_error() calls
*
* Revision 1.2 1996/09/15 14:18:10 brianp
* now use GLframebuffer and GLvisual
*
* Revision 1.1 1996/09/13 01:38:16 brianp
* Initial revision
*
*/
#ifdef PC_HEADER
#include "all.h"
#else
#include <assert.h>
#include <stdlib.h>
#include "alphabuf.h"
#include "blend.h"
#include "context.h"
#include "dlist.h"
#include "macros.h"
#include "pb.h"
#include "span.h"
#include "types.h"
#endif
void gl_BlendFunc( GLcontext* ctx, GLenum sfactor, GLenum dfactor )
{
if (INSIDE_BEGIN_END(ctx)) {
gl_error( ctx, GL_INVALID_OPERATION, "glBlendFunc" );
return;
}
switch (sfactor) {
case GL_ZERO:
case GL_ONE:
case GL_DST_COLOR:
case GL_ONE_MINUS_DST_COLOR:
case GL_SRC_ALPHA:
case GL_ONE_MINUS_SRC_ALPHA:
case GL_DST_ALPHA:
case GL_ONE_MINUS_DST_ALPHA:
case GL_SRC_ALPHA_SATURATE:
ctx->Color.BlendSrc = sfactor;
break;
default:
gl_error( ctx, GL_INVALID_ENUM, "glBlendFunc(sfactor)" );
return;
}
switch (dfactor) {
case GL_ZERO:
case GL_ONE:
case GL_SRC_COLOR:
case GL_ONE_MINUS_SRC_COLOR:
case GL_SRC_ALPHA:
case GL_ONE_MINUS_SRC_ALPHA:
case GL_DST_ALPHA:
case GL_ONE_MINUS_DST_ALPHA:
ctx->Color.BlendDst = dfactor;
break;
default:
gl_error( ctx, GL_INVALID_ENUM, "glBlendFunc(dfactor)" );
}
ctx->NewState |= NEW_RASTER_OPS;
}
/*
* Do the real work of gl_blend_span() and gl_blend_pixels().
* Input: n - number of pixels
* mask - the usual write mask
* In/Out: red, green, blue, alpha - the incoming and modified pixels
* Input: rdest, gdest, bdest, adest - the pixels from the dest color buffer
*/
static void do_blend( GLcontext* ctx, GLuint n, const GLubyte mask[],
GLubyte red[], GLubyte green[],
GLubyte blue[], GLubyte alpha[],
const GLubyte rdest[], const GLubyte gdest[],
const GLubyte bdest[], const GLubyte adest[] )
{
GLuint i;
if (ctx->Color.BlendSrc==GL_SRC_ALPHA
&& ctx->Color.BlendDst==GL_ONE_MINUS_SRC_ALPHA) {
/* Alpha blending */
GLfloat ascale = 256.0f * ctx->Visual->InvAlphaScale;
GLint rmax = (GLint) ctx->Visual->RedScale;
GLint gmax = (GLint) ctx->Visual->GreenScale;
GLint bmax = (GLint) ctx->Visual->BlueScale;
GLint amax = (GLint) ctx->Visual->AlphaScale;
for (i=0;i<n;i++) {
if (mask[i]) {
GLint r, g, b, a;
GLint t = (GLint) ( alpha[i] * ascale ); /* t in [0,256] */
GLint s = 256 - t;
r = (red[i] * t + rdest[i] * s) >> 8;
g = (green[i] * t + gdest[i] * s) >> 8;
b = (blue[i] * t + bdest[i] * s) >> 8;
a = (alpha[i] * t + adest[i] * s) >> 8;
/* kai: I think the following clamping is not needed: */
red[i] = MIN2( r, rmax );
green[i] = MIN2( g, gmax );
blue[i] = MIN2( b, bmax );
alpha[i] = MIN2( a, amax );
}
}
}
else {
/* clipped sum */
if (ctx->Color.BlendSrc==GL_ONE
&& ctx->Color.BlendDst==GL_ONE) {
GLint rmax = (GLint) ctx->Visual->RedScale;
GLint gmax = (GLint) ctx->Visual->GreenScale;
GLint bmax = (GLint) ctx->Visual->BlueScale;
GLint amax = (GLint) ctx->Visual->AlphaScale;
for (i=0; i < n; i++) {
if (mask[i]) {
red[i] = MIN2(rmax, red[i] + rdest[i]);
green[i] = MIN2(gmax, green[i] + gdest[i]);
blue[i] = MIN2(bmax, blue[i] + bdest[i]);
alpha[i] = MIN2(amax, alpha[i] + adest[i]);
}
}
}
/* modulation */
else if ((ctx->Color.BlendSrc==GL_ZERO &&
ctx->Color.BlendDst==GL_SRC_COLOR)
||
(ctx->Color.BlendSrc==GL_DST_COLOR &&
ctx->Color.BlendDst==GL_ZERO)) {
if (ctx->Visual->EightBitColor) {
for (i=0; i < n; i++) {
if (mask[i]) {
red[i] = (red[i] * rdest[i]) / 255;
green[i] = (green[i] * gdest[i]) / 255;
blue[i] = (blue[i] * bdest[i]) / 255;
alpha[i] = (alpha[i] * adest[i]) / 255;
}
}
}
else {
GLint rmax = (GLint) ctx->Visual->RedScale;
GLint gmax = (GLint) ctx->Visual->GreenScale;
GLint bmax = (GLint) ctx->Visual->BlueScale;
GLint amax = (GLint) ctx->Visual->AlphaScale;
for (i=0; i < n; i++) {
if (mask[i]) {
red[i] = (red[i] * rdest[i]) / rmax;
green[i] = (green[i] * gdest[i]) / gmax;
blue[i] = (blue[i] * bdest[i]) / bmax;
alpha[i] = (alpha[i] * adest[i]) / amax;
}
}
}
}else{
/* General cases: */
if (ctx->Visual->EightBitColor) {
for (i=0;i<n;i++) {
if (mask[i]) {
GLint Rs, Gs, Bs, As; /* Source colors */
GLint Rd, Gd, Bd, Ad; /* Dest colors */
GLint Rss, Gss, Bss, Ass; /* Source colors scaled */
GLint Rds, Gds, Bds, Ads; /* Dest colors scaled */
/* Source Color */
Rs = red[i];
Gs = green[i];
Bs = blue[i];
As = alpha[i];
/* Frame buffer color */
Rd = rdest[i];
Gd = gdest[i];
Bd = bdest[i];
Ad = adest[i];
/* Source scaling */
switch (ctx->Color.BlendSrc) {
case GL_ZERO:
Rss = Gss = Bss = Ass = 0;
break;
case GL_ONE:
Rss = Rs * 255;
Gss = Gs * 255;
Bss = Bs * 255;
Ass = As * 255;
break;
case GL_DST_COLOR:
Rss = Rs * Rd;
Gss = Gs * Gd;
Bss = Bs * Bd;
Ass = As * Ad;
break;
case GL_ONE_MINUS_DST_COLOR:
Rss = Rs * (255 - Rd);
Gss = Gs * (255 - Gd);
Bss = Bs * (255 - Bd);
Ass = As * (255 - Ad);
break;
case GL_SRC_ALPHA:
Rss = Rs * As;
Gss = Gs * As;
Bss = Bs * As;
Ass = As * As;
break;
case GL_ONE_MINUS_SRC_ALPHA:
Rss = Rs * (255 - As);
Gss = Gs * (255 - As);
Bss = Bs * (255 - As);
Ass = As * (255 - As);
break;
case GL_DST_ALPHA:
Rss = Rs * Ad;
Gss = Gs * Ad;
Bss = Bs * Ad;
Ass = As * Ad;
break;
case GL_ONE_MINUS_DST_ALPHA:
Rss = Rs * (255 - Ad);
Gss = Gs * (255 - Ad);
Bss = Bs * (255 - Ad);
Ass = As * (255 - Ad);
break;
case GL_SRC_ALPHA_SATURATE:
{
GLint sA = MIN2(As, 255 - Ad);
Rss = Rs * sA;
Gss = Gs * sA;
Bss = Bs * sA;
Ass = As * 255;
break;
}
default:
/* this should never happen */
gl_problem(ctx, "Bad blend source factor in do_blend");
}
/* Dest scaling */
switch (ctx->Color.BlendDst) {
case GL_ZERO:
Rds = Gds = Bds = Ads = 0;
break;
case GL_ONE:
Rds = Rd * 255;
Gds = Gd * 255;
Bds = Bd * 255;
Ads = Ad * 255;
break;
case GL_SRC_COLOR:
Rds = Rd * Rs;
Gds = Gd * Gs;
Bds = Bd * Bs;
Ads = Ad * As;
break;
case GL_ONE_MINUS_SRC_COLOR:
Rds = Rs * (255 - Rs);
Gds = Gs * (255 - Gs);
Bds = Bs * (255 - Bs);
Ads = As * (255 - As);
break;
case GL_SRC_ALPHA:
Rds = Rd * As;
Gds = Gd * As;
Bds = Bd * As;
Ads = Ad * As;
break;
case GL_ONE_MINUS_SRC_ALPHA:
Rds = Rd * (255 - As);
Gds = Gd * (255 - As);
Bds = Bd * (255 - As);
Ads = Ad * (255 - As);
break;
case GL_DST_ALPHA:
Rds = Rd * Ad;
Gds = Gd * Ad;
Bds = Bd * Ad;
Ads = Ad * Ad;
break;
case GL_ONE_MINUS_DST_ALPHA:
Rds = Rd * (255 - Ad);
Gds = Gd * (255 - Ad);
Bds = Bd * (255 - Ad);
Ads = Ad * (255 - Ad);
break;
default:
/* this should never happen */
gl_problem(ctx, "Bad blend dest factor in do_blend");
}
/* compute blended color */
red[i] = MIN2((Rss + Rds) / 255, 255);
green[i] = MIN2((Gss + Gds) / 255, 255);
blue[i] = MIN2((Bss + Bds) / 255, 255);
alpha[i] = MIN2((Ass + Ads) / 255, 255);
}
}
}else{ /* !EightBitColor */
GLfloat rmax = ctx->Visual->RedScale;
GLfloat gmax = ctx->Visual->GreenScale;
GLfloat bmax = ctx->Visual->BlueScale;
GLfloat amax = ctx->Visual->AlphaScale;
GLfloat rscale = 1.0f / rmax;
GLfloat gscale = 1.0f / gmax;
GLfloat bscale = 1.0f / bmax;
GLfloat ascale = 1.0f / amax;
for (i=0;i<n;i++) {
if (mask[i]) {
GLint Rs, Gs, Bs, As; /* Source colors */
GLint Rd, Gd, Bd, Ad; /* Dest colors */
GLfloat sR, sG, sB, sA; /* Source scaling */
GLfloat dR, dG, dB, dA; /* Dest scaling */
GLfloat r, g, b, a;
/* Source Color */
Rs = red[i];
Gs = green[i];
Bs = blue[i];
As = alpha[i];
/* Frame buffer color */
Rd = rdest[i];
Gd = gdest[i];
Bd = bdest[i];
Ad = adest[i];
/* Source scaling */
switch (ctx->Color.BlendSrc) {
case GL_ZERO:
sR = sG = sB = sA = 0.0F;
break;
case GL_ONE:
sR = sG = sB = sA = 1.0F;
break;
case GL_DST_COLOR:
sR = (GLfloat) Rd * rscale;
sG = (GLfloat) Gd * gscale;
sB = (GLfloat) Bd * bscale;
sA = (GLfloat) Ad * ascale;
break;
case GL_ONE_MINUS_DST_COLOR:
sR = 1.0F - (GLfloat) Rd * rscale;
sG = 1.0F - (GLfloat) Gd * gscale;
sB = 1.0F - (GLfloat) Bd * bscale;
sA = 1.0F - (GLfloat) Ad * ascale;
break;
case GL_SRC_ALPHA:
sR = sG = sB = sA = (GLfloat) As * ascale;
break;
case GL_ONE_MINUS_SRC_ALPHA:
sR = sG = sB = sA = (GLfloat) 1.0F - (GLfloat) As * ascale;
break;
case GL_DST_ALPHA:
sR = sG = sB = sA =(GLfloat) Ad * ascale;
break;
case GL_ONE_MINUS_DST_ALPHA:
sR = sG = sB = sA = 1.0F - (GLfloat) Ad * ascale;
break;
case GL_SRC_ALPHA_SATURATE:
if (As < 1.0F - (GLfloat) Ad * ascale) {
sR = sG = sB = (GLfloat) As * ascale;
}
else {
sR = sG = sB = 1.0F - (GLfloat) Ad * ascale;
}
sA = 1.0;
break;
default:
/* this should never happen */
gl_problem(ctx, "Bad blend source factor in do_blend");
}
/* Dest scaling */
switch (ctx->Color.BlendDst) {
case GL_ZERO:
dR = dG = dB = dA = 0.0F;
break;
case GL_ONE:
dR = dG = dB = dA = 1.0F;
break;
case GL_SRC_COLOR:
dR = (GLfloat) Rs * rscale;
dG = (GLfloat) Gs * gscale;
dB = (GLfloat) Bs * bscale;
dA = (GLfloat) As * ascale;
break;
case GL_ONE_MINUS_SRC_COLOR:
dR = 1.0F - (GLfloat) Rs * rscale;
dG = 1.0F - (GLfloat) Gs * gscale;
dB = 1.0F - (GLfloat) Bs * bscale;
dA = 1.0F - (GLfloat) As * ascale;
break;
case GL_SRC_ALPHA:
dR = dG = dB = dA = (GLfloat) As * ascale;
break;
case GL_ONE_MINUS_SRC_ALPHA:
dR = dG = dB = dA = (GLfloat) 1.0F - (GLfloat) As * ascale;
break;
case GL_DST_ALPHA:
dR = dG = dB = dA = (GLfloat) Ad * ascale;
break;
case GL_ONE_MINUS_DST_ALPHA:
dR = dG = dB = dA = 1.0F - (GLfloat) Ad * ascale;
break;
default:
/* this should never happen */
gl_problem(ctx, "Bad blend dest factor in do_blend");
}
#ifdef DEBUG
assert( sR>= 0.0 && sR<=1.0 );
assert( sG>= 0.0 && sG<=1.0 );
assert( sB>= 0.0 && sB<=1.0 );
assert( sA>= 0.0 && sA<=1.0 );
assert( dR>= 0.0 && dR<=1.0 );
assert( dG>= 0.0 && dG<=1.0 );
assert( dB>= 0.0 && dB<=1.0 );
assert( dA>= 0.0 && dA<=1.0 );
#endif
/* compute blended color */
r = Rs * sR + Rd * dR;
g = Gs * sG + Gd * dG;
b = Bs * sB + Bd * dB;
a = As * sA + Ad * dA;
red[i] = (GLint) CLAMP( r, 0.0F, rmax );
green[i] = (GLint) CLAMP( g, 0.0F, gmax );
blue[i] = (GLint) CLAMP( b, 0.0F, bmax );
alpha[i] = (GLint) CLAMP( a, 0.0F, amax );
}
}
}
}
}
}
/*
* Apply the blending operator to a span of pixels.
* Input: n - number of pixels in span
* x, y - location of leftmost pixel in span in window coords.
* mask - boolean mask indicating which pixels to blend.
* In/Out: red, green, blue, alpha - pixel values
*/
void gl_blend_span( GLcontext* ctx, GLuint n, GLint x, GLint y,
GLubyte red[], GLubyte green[],
GLubyte blue[], GLubyte alpha[],
GLubyte mask[] )
{
GLubyte rdest[MAX_WIDTH], gdest[MAX_WIDTH];
GLubyte bdest[MAX_WIDTH], adest[MAX_WIDTH];
/* Read span of current frame buffer pixels */
gl_read_color_span( ctx, n, x, y, rdest, gdest, bdest, adest );
do_blend( ctx, n, mask, red, green, blue, alpha, rdest, gdest, bdest, adest );
}
/*
* Apply the blending operator to an array of pixels.
* Input: n - number of pixels in span
* x, y - array of pixel locations
* mask - boolean mask indicating which pixels to blend.
* In/Out: red, green, blue, alpha - array of pixel values
*/
void gl_blend_pixels( GLcontext* ctx,
GLuint n, const GLint x[], const GLint y[],
GLubyte red[], GLubyte green[],
GLubyte blue[], GLubyte alpha[],
GLubyte mask[] )
{
GLubyte rdest[PB_SIZE], gdest[PB_SIZE], bdest[PB_SIZE], adest[PB_SIZE];
/* Read pixels from current color buffer */
(*ctx->Driver.ReadColorPixels)( ctx, n, x, y, rdest, gdest, bdest, adest, mask );
if (ctx->RasterMask & ALPHABUF_BIT) {
gl_read_alpha_pixels( ctx, n, x, y, adest, mask );
}
do_blend( ctx, n, mask, red, green, blue, alpha, rdest, gdest, bdest, adest );
}