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-rw-r--r--xc/extras/Mesa/src/swrast/s_accum.c530
1 files changed, 530 insertions, 0 deletions
diff --git a/xc/extras/Mesa/src/swrast/s_accum.c b/xc/extras/Mesa/src/swrast/s_accum.c
new file mode 100644
index 000000000..fe708cbbc
--- /dev/null
+++ b/xc/extras/Mesa/src/swrast/s_accum.c
@@ -0,0 +1,530 @@
+/* $Id: s_accum.c,v 1.2 2002/02/14 01:59:39 dawes Exp $ */
+
+/*
+ * Mesa 3-D graphics library
+ * Version: 3.5
+ *
+ * Copyright (C) 1999-2001 Brian Paul All Rights Reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+ * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
+ * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
+ * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+
+
+#include "glheader.h"
+#include "context.h"
+#include "macros.h"
+#include "mmath.h"
+#include "mem.h"
+
+#include "s_accum.h"
+#include "s_alphabuf.h"
+#include "s_context.h"
+#include "s_masking.h"
+#include "s_span.h"
+
+
+/*
+ * Accumulation buffer notes
+ *
+ * Normally, accumulation buffer values are GLshorts with values in
+ * [-32767, 32767] which represent floating point colors in [-1, 1],
+ * as suggested by the OpenGL specification.
+ *
+ * We optimize for the common case used for full-scene antialiasing:
+ * // start with accum buffer cleared to zero
+ * glAccum(GL_LOAD, w); // or GL_ACCUM the first image
+ * glAccum(GL_ACCUM, w);
+ * ...
+ * glAccum(GL_ACCUM, w);
+ * glAccum(GL_RETURN, 1.0);
+ * That is, we start with an empty accumulation buffer and accumulate
+ * n images, each with weight w = 1/n.
+ * In this scenario, we can simply store unscaled integer values in
+ * the accum buffer instead of scaled integers. We'll also keep track
+ * of the w value so when we do GL_RETURN we simply divide the accumulated
+ * values by n (=1/w).
+ * This lets us avoid _many_ int->float->int conversions.
+ */
+
+
+#if CHAN_BITS == 8
+#define USE_OPTIMIZED_ACCUM /* enable the optimization */
+#endif
+
+
+
+void
+_mesa_alloc_accum_buffer( GLcontext *ctx )
+{
+ SWcontext *swrast = SWRAST_CONTEXT(ctx);
+ GLint n;
+
+ if (ctx->DrawBuffer->Accum) {
+ FREE( ctx->DrawBuffer->Accum );
+ ctx->DrawBuffer->Accum = NULL;
+ }
+
+ /* allocate accumulation buffer if not already present */
+ n = ctx->DrawBuffer->Width * ctx->DrawBuffer->Height * 4 * sizeof(GLaccum);
+ ctx->DrawBuffer->Accum = (GLaccum *) MALLOC( n );
+ if (!ctx->DrawBuffer->Accum) {
+ /* unable to setup accumulation buffer */
+ _mesa_error( ctx, GL_OUT_OF_MEMORY, "glAccum" );
+ }
+#ifdef USE_OPTIMIZED_ACCUM
+ swrast->_IntegerAccumMode = GL_TRUE;
+#else
+ swrast->_IntegerAccumMode = GL_FALSE;
+#endif
+ swrast->_IntegerAccumScaler = 0.0;
+}
+
+
+
+
+
+
+/*
+ * This is called when we fall out of optimized/unscaled accum buffer mode.
+ * That is, we convert each unscaled accum buffer value into a scaled value
+ * representing the range[-1, 1].
+ */
+static void rescale_accum( GLcontext *ctx )
+{
+ SWcontext *swrast = SWRAST_CONTEXT(ctx);
+ const GLuint n = ctx->DrawBuffer->Width * ctx->DrawBuffer->Height * 4;
+ const GLfloat s = swrast->_IntegerAccumScaler * (32767.0F / CHAN_MAXF);
+ GLaccum *accum = ctx->DrawBuffer->Accum;
+ GLuint i;
+
+ assert(swrast->_IntegerAccumMode);
+ assert(accum);
+
+ for (i = 0; i < n; i++) {
+ accum[i] = (GLaccum) (accum[i] * s);
+ }
+
+ swrast->_IntegerAccumMode = GL_FALSE;
+}
+
+
+
+
+
+
+/*
+ * Clear the accumulation Buffer.
+ */
+void
+_mesa_clear_accum_buffer( GLcontext *ctx )
+{
+ SWcontext *swrast = SWRAST_CONTEXT(ctx);
+ GLuint buffersize;
+ GLfloat acc_scale;
+
+ if (ctx->Visual.accumRedBits==0) {
+ /* No accumulation buffer! */
+ return;
+ }
+
+ if (sizeof(GLaccum)==1) {
+ acc_scale = 127.0;
+ }
+ else if (sizeof(GLaccum)==2) {
+ acc_scale = 32767.0;
+ }
+ else {
+ acc_scale = 1.0F;
+ }
+
+ /* number of pixels */
+ buffersize = ctx->DrawBuffer->Width * ctx->DrawBuffer->Height;
+
+ if (!ctx->DrawBuffer->Accum) {
+ /* try to alloc accumulation buffer */
+ ctx->DrawBuffer->Accum = (GLaccum *)
+ MALLOC( buffersize * 4 * sizeof(GLaccum) );
+ }
+
+ if (ctx->DrawBuffer->Accum) {
+ if (ctx->Scissor.Enabled) {
+ /* Limit clear to scissor box */
+ const GLaccum r = (GLaccum) (ctx->Accum.ClearColor[0] * acc_scale);
+ const GLaccum g = (GLaccum) (ctx->Accum.ClearColor[1] * acc_scale);
+ const GLaccum b = (GLaccum) (ctx->Accum.ClearColor[2] * acc_scale);
+ const GLaccum a = (GLaccum) (ctx->Accum.ClearColor[3] * acc_scale);
+ GLint i, j;
+ GLint width, height;
+ GLaccum *row;
+ /* size of region to clear */
+ width = 4 * (ctx->DrawBuffer->_Xmax - ctx->DrawBuffer->_Xmin);
+ height = ctx->DrawBuffer->_Ymax - ctx->DrawBuffer->_Ymin;
+ /* ptr to first element to clear */
+ row = ctx->DrawBuffer->Accum
+ + 4 * (ctx->DrawBuffer->_Ymin * ctx->DrawBuffer->Width
+ + ctx->DrawBuffer->_Xmin);
+ for (j=0;j<height;j++) {
+ for (i=0;i<width;i+=4) {
+ row[i+0] = r;
+ row[i+1] = g;
+ row[i+2] = b;
+ row[i+3] = a;
+ }
+ row += 4 * ctx->DrawBuffer->Width;
+ }
+ }
+ else {
+ /* clear whole buffer */
+ if (ctx->Accum.ClearColor[0]==0.0 &&
+ ctx->Accum.ClearColor[1]==0.0 &&
+ ctx->Accum.ClearColor[2]==0.0 &&
+ ctx->Accum.ClearColor[3]==0.0) {
+ /* Black */
+ BZERO( ctx->DrawBuffer->Accum, buffersize * 4 * sizeof(GLaccum) );
+ }
+ else {
+ /* Not black */
+ const GLaccum r = (GLaccum) (ctx->Accum.ClearColor[0] * acc_scale);
+ const GLaccum g = (GLaccum) (ctx->Accum.ClearColor[1] * acc_scale);
+ const GLaccum b = (GLaccum) (ctx->Accum.ClearColor[2] * acc_scale);
+ const GLaccum a = (GLaccum) (ctx->Accum.ClearColor[3] * acc_scale);
+ GLaccum *acc = ctx->DrawBuffer->Accum;
+ GLuint i;
+ for (i=0;i<buffersize;i++) {
+ *acc++ = r;
+ *acc++ = g;
+ *acc++ = b;
+ *acc++ = a;
+ }
+ }
+ }
+
+ /* update optimized accum state vars */
+ if (ctx->Accum.ClearColor[0] == 0.0 && ctx->Accum.ClearColor[1] == 0.0 &&
+ ctx->Accum.ClearColor[2] == 0.0 && ctx->Accum.ClearColor[3] == 0.0) {
+#ifdef USE_OPTIMIZED_ACCUM
+ swrast->_IntegerAccumMode = GL_TRUE;
+#else
+ swrast->_IntegerAccumMode = GL_FALSE;
+#endif
+ swrast->_IntegerAccumScaler = 0.0; /* denotes empty accum buffer */
+ }
+ else {
+ swrast->_IntegerAccumMode = GL_FALSE;
+ }
+ }
+}
+
+
+void
+_swrast_Accum( GLcontext *ctx, GLenum op, GLfloat value,
+ GLint xpos, GLint ypos,
+ GLint width, GLint height )
+
+{
+ SWcontext *swrast = SWRAST_CONTEXT(ctx);
+ GLuint width4;
+ GLfloat acc_scale;
+ GLchan rgba[MAX_WIDTH][4];
+ const GLuint colorMask = *((GLuint *) &ctx->Color.ColorMask);
+
+
+ if (SWRAST_CONTEXT(ctx)->NewState)
+ _swrast_validate_derived( ctx );
+
+ if (!ctx->DrawBuffer->Accum) {
+ _mesa_warning(ctx,
+ "Calling glAccum() without an accumulation "
+ "buffer (low memory?)");
+ return;
+ }
+
+ if (sizeof(GLaccum)==1) {
+ acc_scale = 127.0;
+ }
+ else if (sizeof(GLaccum)==2) {
+ acc_scale = 32767.0;
+ }
+ else {
+ acc_scale = 1.0F;
+ }
+
+ width4 = 4 * width;
+
+ switch (op) {
+ case GL_ADD:
+ if (value != 0.0F) {
+ const GLaccum val = (GLaccum) (value * acc_scale);
+ GLint j;
+ /* Leave optimized accum buffer mode */
+ if (swrast->_IntegerAccumMode)
+ rescale_accum(ctx);
+ for (j = 0; j < height; j++) {
+ GLaccum *acc = ctx->DrawBuffer->Accum + ypos * width4 + 4*xpos;
+ GLuint i;
+ for (i = 0; i < width4; i++) {
+ acc[i] += val;
+ }
+ ypos++;
+ }
+ }
+ break;
+
+ case GL_MULT:
+ if (value != 1.0F) {
+ GLint j;
+ /* Leave optimized accum buffer mode */
+ if (swrast->_IntegerAccumMode)
+ rescale_accum(ctx);
+ for (j = 0; j < height; j++) {
+ GLaccum *acc = ctx->DrawBuffer->Accum + ypos * width4 + 4 * xpos;
+ GLuint i;
+ for (i = 0; i < width4; i++) {
+ acc[i] = (GLaccum) ( (GLfloat) acc[i] * value );
+ }
+ ypos++;
+ }
+ }
+ break;
+
+ case GL_ACCUM:
+ if (value == 0.0F)
+ return;
+
+ (*swrast->Driver.SetReadBuffer)( ctx, ctx->ReadBuffer,
+ ctx->Pixel.DriverReadBuffer );
+
+ /* May have to leave optimized accum buffer mode */
+ if (swrast->_IntegerAccumScaler == 0.0 && value > 0.0 && value <= 1.0)
+ swrast->_IntegerAccumScaler = value;
+ if (swrast->_IntegerAccumMode && value != swrast->_IntegerAccumScaler)
+ rescale_accum(ctx);
+
+ RENDER_START(swrast,ctx);
+
+ if (swrast->_IntegerAccumMode) {
+ /* simply add integer color values into accum buffer */
+ GLint j;
+ GLaccum *acc = ctx->DrawBuffer->Accum + ypos * width4 + xpos * 4;
+ assert(swrast->_IntegerAccumScaler > 0.0);
+ assert(swrast->_IntegerAccumScaler <= 1.0);
+ for (j = 0; j < height; j++) {
+
+ GLint i, i4;
+ _mesa_read_rgba_span(ctx, ctx->DrawBuffer, width, xpos, ypos, rgba);
+ for (i = i4 = 0; i < width; i++, i4+=4) {
+ acc[i4+0] += rgba[i][RCOMP];
+ acc[i4+1] += rgba[i][GCOMP];
+ acc[i4+2] += rgba[i][BCOMP];
+ acc[i4+3] += rgba[i][ACOMP];
+ }
+ acc += width4;
+ ypos++;
+ }
+ }
+ else {
+ /* scaled integer (or float) accum buffer */
+ const GLfloat rscale = value * acc_scale / CHAN_MAXF;
+ const GLfloat gscale = value * acc_scale / CHAN_MAXF;
+ const GLfloat bscale = value * acc_scale / CHAN_MAXF;
+ const GLfloat ascale = value * acc_scale / CHAN_MAXF;
+ GLint j;
+ for (j=0;j<height;j++) {
+ GLaccum *acc = ctx->DrawBuffer->Accum + ypos * width4 + xpos * 4;
+ GLint i;
+ _mesa_read_rgba_span(ctx, ctx->DrawBuffer, width, xpos, ypos, rgba);
+ for (i=0;i<width;i++) {
+ acc[0] += (GLaccum) ( (GLfloat) rgba[i][RCOMP] * rscale );
+ acc[1] += (GLaccum) ( (GLfloat) rgba[i][GCOMP] * gscale );
+ acc[2] += (GLaccum) ( (GLfloat) rgba[i][BCOMP] * bscale );
+ acc[3] += (GLaccum) ( (GLfloat) rgba[i][ACOMP] * ascale );
+ acc += 4;
+ }
+ ypos++;
+ }
+ }
+ /* restore read buffer = draw buffer (the default) */
+ (*swrast->Driver.SetReadBuffer)( ctx, ctx->DrawBuffer,
+ ctx->Color.DriverDrawBuffer );
+ RENDER_FINISH(swrast,ctx);
+ break;
+
+ case GL_LOAD:
+ (*swrast->Driver.SetReadBuffer)( ctx, ctx->ReadBuffer,
+ ctx->Pixel.DriverReadBuffer );
+
+ /* This is a change to go into optimized accum buffer mode */
+ if (value > 0.0 && value <= 1.0) {
+#ifdef USE_OPTIMIZED_ACCUM
+ swrast->_IntegerAccumMode = GL_TRUE;
+#else
+ swrast->_IntegerAccumMode = GL_FALSE;
+#endif
+ swrast->_IntegerAccumScaler = value;
+ }
+ else {
+ swrast->_IntegerAccumMode = GL_FALSE;
+ swrast->_IntegerAccumScaler = 0.0;
+ }
+
+ RENDER_START(swrast,ctx);
+ if (swrast->_IntegerAccumMode) {
+ /* just copy values into accum buffer */
+ GLint j;
+ GLaccum *acc = ctx->DrawBuffer->Accum + ypos * width4 + xpos * 4;
+ assert(swrast->_IntegerAccumScaler > 0.0);
+ assert(swrast->_IntegerAccumScaler <= 1.0);
+ for (j = 0; j < height; j++) {
+ GLint i, i4;
+ _mesa_read_rgba_span(ctx, ctx->DrawBuffer, width, xpos, ypos, rgba);
+ for (i = i4 = 0; i < width; i++, i4 += 4) {
+ acc[i4+0] = rgba[i][RCOMP];
+ acc[i4+1] = rgba[i][GCOMP];
+ acc[i4+2] = rgba[i][BCOMP];
+ acc[i4+3] = rgba[i][ACOMP];
+ }
+ acc += width4;
+ ypos++;
+ }
+ }
+ else {
+ /* scaled integer (or float) accum buffer */
+ const GLfloat rscale = value * acc_scale / CHAN_MAXF;
+ const GLfloat gscale = value * acc_scale / CHAN_MAXF;
+ const GLfloat bscale = value * acc_scale / CHAN_MAXF;
+ const GLfloat ascale = value * acc_scale / CHAN_MAXF;
+#if 0
+ const GLfloat d = 3.0 / acc_scale; /* XXX what's this? */
+#endif
+ GLint i, j;
+ for (j = 0; j < height; j++) {
+ GLaccum *acc = ctx->DrawBuffer->Accum + ypos * width4 + xpos * 4;
+ _mesa_read_rgba_span(ctx, ctx->DrawBuffer, width, xpos, ypos, rgba);
+ for (i=0;i<width;i++) {
+#if 0
+ *acc++ = (GLaccum) ((GLfloat) rgba[i][RCOMP] * rscale + d);
+ *acc++ = (GLaccum) ((GLfloat) rgba[i][GCOMP] * gscale + d);
+ *acc++ = (GLaccum) ((GLfloat) rgba[i][BCOMP] * bscale + d);
+ *acc++ = (GLaccum) ((GLfloat) rgba[i][ACOMP] * ascale + d);
+#else
+ *acc++ = (GLaccum) ((GLfloat) rgba[i][RCOMP] * rscale);
+ *acc++ = (GLaccum) ((GLfloat) rgba[i][GCOMP] * gscale);
+ *acc++ = (GLaccum) ((GLfloat) rgba[i][BCOMP] * bscale);
+ *acc++ = (GLaccum) ((GLfloat) rgba[i][ACOMP] * ascale);
+#endif
+ }
+ ypos++;
+ }
+ }
+
+ /* restore read buffer = draw buffer (the default) */
+ (*swrast->Driver.SetReadBuffer)( ctx, ctx->DrawBuffer,
+ ctx->Color.DriverDrawBuffer );
+ RENDER_FINISH(swrast,ctx);
+ break;
+
+ case GL_RETURN:
+ /* May have to leave optimized accum buffer mode */
+ if (swrast->_IntegerAccumMode && value != 1.0)
+ rescale_accum(ctx);
+
+ RENDER_START(swrast,ctx);
+#ifdef USE_OPTIMIZED_ACCUM
+ if (swrast->_IntegerAccumMode && swrast->_IntegerAccumScaler > 0) {
+ /* build lookup table to avoid many floating point multiplies */
+ static GLchan multTable[32768];
+ static GLfloat prevMult = 0.0;
+ const GLfloat mult = swrast->_IntegerAccumScaler;
+ const GLint max = MIN2((GLint) (256 / mult), 32767);
+ GLint j;
+ if (mult != prevMult) {
+ for (j = 0; j < max; j++)
+ multTable[j] = IROUND((GLfloat) j * mult);
+ prevMult = mult;
+ }
+
+ assert(swrast->_IntegerAccumScaler > 0.0);
+ assert(swrast->_IntegerAccumScaler <= 1.0);
+ for (j = 0; j < height; j++) {
+ const GLaccum *acc = ctx->DrawBuffer->Accum + ypos * width4 + xpos*4;
+ GLint i, i4;
+ for (i = i4 = 0; i < width; i++, i4 += 4) {
+ ASSERT(acc[i4+0] < max);
+ ASSERT(acc[i4+1] < max);
+ ASSERT(acc[i4+2] < max);
+ ASSERT(acc[i4+3] < max);
+ rgba[i][RCOMP] = multTable[acc[i4+0]];
+ rgba[i][GCOMP] = multTable[acc[i4+1]];
+ rgba[i][BCOMP] = multTable[acc[i4+2]];
+ rgba[i][ACOMP] = multTable[acc[i4+3]];
+ }
+ if (colorMask != 0xffffffff) {
+ _mesa_mask_rgba_span( ctx, width, xpos, ypos, rgba );
+ }
+ (*swrast->Driver.WriteRGBASpan)( ctx, width, xpos, ypos,
+ (const GLchan (*)[4])rgba, NULL );
+ if (ctx->DrawBuffer->UseSoftwareAlphaBuffers
+ && ctx->Color.ColorMask[ACOMP]) {
+ _mesa_write_alpha_span(ctx, width, xpos, ypos,
+ (CONST GLchan (*)[4]) rgba, NULL);
+ }
+ ypos++;
+ }
+ }
+ else
+#endif /* USE_OPTIMIZED_ACCUM */
+ {
+ /* scaled integer (or float) accum buffer */
+ const GLfloat rscale = value / acc_scale * CHAN_MAXF;
+ const GLfloat gscale = value / acc_scale * CHAN_MAXF;
+ const GLfloat bscale = value / acc_scale * CHAN_MAXF;
+ const GLfloat ascale = value / acc_scale * CHAN_MAXF;
+ GLint i, j;
+ for (j=0;j<height;j++) {
+ const GLaccum *acc = ctx->DrawBuffer->Accum + ypos * width4 + xpos*4;
+ for (i=0;i<width;i++) {
+ GLint r = IROUND( (GLfloat) (acc[0]) * rscale );
+ GLint g = IROUND( (GLfloat) (acc[1]) * gscale );
+ GLint b = IROUND( (GLfloat) (acc[2]) * bscale );
+ GLint a = IROUND( (GLfloat) (acc[3]) * ascale );
+ acc += 4;
+ rgba[i][RCOMP] = CLAMP( r, 0, CHAN_MAX );
+ rgba[i][GCOMP] = CLAMP( g, 0, CHAN_MAX );
+ rgba[i][BCOMP] = CLAMP( b, 0, CHAN_MAX );
+ rgba[i][ACOMP] = CLAMP( a, 0, CHAN_MAX );
+ }
+ if (colorMask != 0xffffffff) {
+ _mesa_mask_rgba_span( ctx, width, xpos, ypos, rgba );
+ }
+ (*swrast->Driver.WriteRGBASpan)( ctx, width, xpos, ypos,
+ (const GLchan (*)[4])rgba, NULL );
+ if (ctx->DrawBuffer->UseSoftwareAlphaBuffers
+ && ctx->Color.ColorMask[ACOMP]) {
+ _mesa_write_alpha_span(ctx, width, xpos, ypos,
+ (CONST GLchan (*)[4]) rgba, NULL);
+ }
+ ypos++;
+ }
+ }
+ RENDER_FINISH(swrast,ctx);
+ break;
+
+ default:
+ _mesa_error( ctx, GL_INVALID_ENUM, "glAccum" );
+ }
+}
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