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-rw-r--r--src/mesa/swrast/s_span.c1109
1 files changed, 1109 insertions, 0 deletions
diff --git a/src/mesa/swrast/s_span.c b/src/mesa/swrast/s_span.c
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index 0000000000..ca02802ceb
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+++ b/src/mesa/swrast/s_span.c
@@ -0,0 +1,1109 @@
+/* $Id: s_span.c,v 1.1 2000/10/31 18:00:04 keithw Exp $ */
+
+/*
+ * Mesa 3-D graphics library
+ * Version: 3.5
+ *
+ * Copyright (C) 1999-2000 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.
+ */
+
+
+/*
+ * pixel span rasterization:
+ * These functions implement the rasterization pipeline.
+ */
+
+
+#include "glheader.h"
+#include "colormac.h"
+#include "macros.h"
+#include "mem.h"
+
+#include "s_alpha.h"
+#include "s_alphabuf.h"
+#include "s_blend.h"
+#include "s_depth.h"
+#include "s_fog.h"
+#include "s_logic.h"
+#include "s_masking.h"
+#include "s_scissor.h"
+#include "s_span.h"
+#include "s_stencil.h"
+#include "s_texture.h"
+
+
+
+
+/*
+ * Apply the current polygon stipple pattern to a span of pixels.
+ */
+static void stipple_polygon_span( GLcontext *ctx,
+ GLuint n, GLint x, GLint y, GLubyte mask[] )
+{
+ register GLuint i, m, stipple, highbit=0x80000000;
+
+ stipple = ctx->PolygonStipple[y % 32];
+ m = highbit >> (GLuint) (x % 32);
+
+ for (i=0;i<n;i++) {
+ if ((m & stipple)==0) {
+ mask[i] = 0;
+ }
+ m = m >> 1;
+ if (m==0) {
+ m = 0x80000000;
+ }
+ }
+}
+
+
+
+/*
+ * Clip a pixel span to the current buffer/window boundaries.
+ * Return: 0 = all pixels clipped
+ * 1 = at least one pixel is visible
+ */
+static GLuint clip_span( GLcontext *ctx,
+ GLint n, GLint x, GLint y, GLubyte mask[] )
+{
+ GLint i;
+
+ /* Clip to top and bottom */
+ if (y < 0 || y >= ctx->DrawBuffer->Height) {
+ return 0;
+ }
+
+ /* Clip to left and right */
+ if (x >= 0 && x + n <= ctx->DrawBuffer->Width) {
+ /* no clipping needed */
+ return 1;
+ }
+ else if (x + n <= 0) {
+ /* completely off left side */
+ return 0;
+ }
+ else if (x >= ctx->DrawBuffer->Width) {
+ /* completely off right side */
+ return 0;
+ }
+ else {
+ /* clip-test each pixel, this could be done better */
+ for (i=0;i<n;i++) {
+ if (x + i < 0 || x + i >= ctx->DrawBuffer->Width) {
+ mask[i] = 0;
+ }
+ }
+ return 1;
+ }
+}
+
+
+
+/*
+ * Draw to more than one color buffer (or none).
+ */
+static void multi_write_index_span( GLcontext *ctx, GLuint n,
+ GLint x, GLint y, const GLuint indexes[],
+ const GLubyte mask[] )
+{
+ GLuint bufferBit;
+
+ if (ctx->Color.DrawBuffer == GL_NONE)
+ return;
+
+ /* loop over four possible dest color buffers */
+ for (bufferBit = 1; bufferBit <= 8; bufferBit = bufferBit << 1) {
+ if (bufferBit & ctx->Color.DrawDestMask) {
+ GLuint indexTmp[MAX_WIDTH];
+ ASSERT(n < MAX_WIDTH);
+
+ if (bufferBit == FRONT_LEFT_BIT)
+ (void) (*ctx->Driver.SetDrawBuffer)( ctx, GL_FRONT_LEFT);
+ else if (bufferBit == FRONT_RIGHT_BIT)
+ (void) (*ctx->Driver.SetDrawBuffer)( ctx, GL_FRONT_RIGHT);
+ else if (bufferBit == BACK_LEFT_BIT)
+ (void) (*ctx->Driver.SetDrawBuffer)( ctx, GL_BACK_LEFT);
+ else
+ (void) (*ctx->Driver.SetDrawBuffer)( ctx, GL_BACK_RIGHT);
+
+ /* make copy of incoming indexes */
+ MEMCPY( indexTmp, indexes, n * sizeof(GLuint) );
+ if (ctx->Color.IndexLogicOpEnabled) {
+ _mesa_logicop_ci_span( ctx, n, x, y, indexTmp, mask );
+ }
+ if (ctx->Color.IndexMask == 0) {
+ break;
+ }
+ else if (ctx->Color.IndexMask != 0xffffffff) {
+ _mesa_mask_index_span( ctx, n, x, y, indexTmp );
+ }
+ (*ctx->Driver.WriteCI32Span)( ctx, n, x, y, indexTmp, mask );
+ }
+ }
+
+ /* restore default dest buffer */
+ (void) (*ctx->Driver.SetDrawBuffer)( ctx, ctx->Color.DriverDrawBuffer);
+}
+
+
+
+/*
+ * Write a horizontal span of color index pixels to the frame buffer.
+ * Stenciling, Depth-testing, etc. are done as needed.
+ * Input: n - number of pixels in the span
+ * x, y - location of leftmost pixel in the span
+ * z - array of [n] z-values
+ * index - array of [n] color indexes
+ * primitive - either GL_POINT, GL_LINE, GL_POLYGON, or GL_BITMAP
+ */
+void gl_write_index_span( GLcontext *ctx,
+ GLuint n, GLint x, GLint y, const GLdepth z[],
+ const GLfixed fog[],
+ GLuint indexIn[], GLenum primitive )
+{
+ const GLuint modBits = FOG_BIT | BLEND_BIT | MASKING_BIT | LOGIC_OP_BIT;
+ GLubyte mask[MAX_WIDTH];
+ GLuint indexBackup[MAX_WIDTH];
+ GLuint *index; /* points to indexIn or indexBackup */
+
+ /* init mask to 1's (all pixels are to be written) */
+ MEMSET(mask, 1, n);
+
+ if ((ctx->RasterMask & WINCLIP_BIT) || primitive==GL_BITMAP) {
+ if (clip_span(ctx,n,x,y,mask)==0) {
+ return;
+ }
+ }
+
+ if ((primitive==GL_BITMAP && (ctx->RasterMask & modBits))
+ || (ctx->RasterMask & MULTI_DRAW_BIT)) {
+ /* Make copy of color indexes */
+ MEMCPY( indexBackup, indexIn, n * sizeof(GLuint) );
+ index = indexBackup;
+ }
+ else {
+ index = indexIn;
+ }
+
+ /* Per-pixel fog */
+ if (ctx->Fog.Enabled) {
+ if (fog && ctx->Hint.Fog != GL_NICEST)
+ _mesa_fog_ci_pixels( ctx, n, fog, index );
+ else
+ _mesa_depth_fog_ci_pixels( ctx, n, z, index );
+ }
+
+ /* Do the scissor test */
+ if (ctx->Scissor.Enabled) {
+ if (gl_scissor_span( ctx, n, x, y, mask )==0) {
+ return;
+ }
+ }
+
+ /* Polygon Stippling */
+ if (ctx->Polygon.StippleFlag && primitive==GL_POLYGON) {
+ stipple_polygon_span( ctx, n, x, y, mask );
+ }
+
+ if (ctx->Stencil.Enabled) {
+ /* first stencil test */
+ if (_mesa_stencil_and_ztest_span(ctx, n, x, y, z, mask) == GL_FALSE) {
+ return;
+ }
+ }
+ else if (ctx->Depth.Test) {
+ /* regular depth testing */
+ if (_mesa_depth_test_span( ctx, n, x, y, z, mask )==0) return;
+ }
+
+ /* if we get here, something passed the depth test */
+ ctx->OcclusionResult = GL_TRUE;
+
+ if (ctx->RasterMask & MULTI_DRAW_BIT) {
+ /* draw to zero or two or more buffers */
+ multi_write_index_span( ctx, n, x, y, index, mask );
+ }
+ else {
+ /* normal situation: draw to exactly one buffer */
+ if (ctx->Color.IndexLogicOpEnabled) {
+ _mesa_logicop_ci_span( ctx, n, x, y, index, mask );
+ }
+
+ if (ctx->Color.IndexMask == 0) {
+ return;
+ }
+ else if (ctx->Color.IndexMask != 0xffffffff) {
+ _mesa_mask_index_span( ctx, n, x, y, index );
+ }
+
+ /* write pixels */
+ (*ctx->Driver.WriteCI32Span)( ctx, n, x, y, index, mask );
+ }
+}
+
+
+
+
+void gl_write_monoindex_span( GLcontext *ctx,
+ GLuint n, GLint x, GLint y,
+ const GLdepth z[],
+ const GLfixed fog[],
+ GLuint index, GLenum primitive )
+{
+ GLubyte mask[MAX_WIDTH];
+ GLuint i;
+
+ /* init mask to 1's (all pixels are to be written) */
+ MEMSET(mask, 1, n);
+
+ if ((ctx->RasterMask & WINCLIP_BIT) || primitive==GL_BITMAP) {
+ if (clip_span( ctx, n, x, y, mask)==0) {
+ return;
+ }
+ }
+
+ /* Do the scissor test */
+ if (ctx->Scissor.Enabled) {
+ if (gl_scissor_span( ctx, n, x, y, mask )==0) {
+ return;
+ }
+ }
+
+ /* Polygon Stippling */
+ if (ctx->Polygon.StippleFlag && primitive==GL_POLYGON) {
+ stipple_polygon_span( ctx, n, x, y, mask );
+ }
+
+ if (ctx->Stencil.Enabled) {
+ /* first stencil test */
+ if (_mesa_stencil_and_ztest_span(ctx, n, x, y, z, mask) == GL_FALSE) {
+ return;
+ }
+ }
+ else if (ctx->Depth.Test) {
+ /* regular depth testing */
+ if (_mesa_depth_test_span( ctx, n, x, y, z, mask )==0) return;
+ }
+
+ /* if we get here, something passed the depth test */
+ ctx->OcclusionResult = GL_TRUE;
+
+ if (ctx->Color.DrawBuffer == GL_NONE) {
+ /* write no pixels */
+ return;
+ }
+
+ if (ctx->Fog.Enabled
+ || ctx->Color.IndexLogicOpEnabled
+ || ctx->Color.IndexMask != 0xffffffff) {
+ /* different index per pixel */
+ GLuint indexes[MAX_WIDTH];
+ for (i=0;i<n;i++) {
+ indexes[i] = index;
+ }
+
+ if (ctx->Fog.Enabled) {
+ if (fog && ctx->Hint.Fog != GL_NICEST)
+ _mesa_fog_ci_pixels( ctx, n, fog, indexes );
+ else
+ _mesa_depth_fog_ci_pixels( ctx, n, z, indexes );
+ }
+
+ if (ctx->Color.IndexLogicOpEnabled) {
+ _mesa_logicop_ci_span( ctx, n, x, y, indexes, mask );
+ }
+
+ if (ctx->RasterMask & MULTI_DRAW_BIT) {
+ /* draw to zero or two or more buffers */
+ multi_write_index_span( ctx, n, x, y, indexes, mask );
+ }
+ else {
+ /* normal situation: draw to exactly one buffer */
+ if (ctx->Color.IndexLogicOpEnabled) {
+ _mesa_logicop_ci_span( ctx, n, x, y, indexes, mask );
+ }
+ if (ctx->Color.IndexMask == 0) {
+ return;
+ }
+ else if (ctx->Color.IndexMask != 0xffffffff) {
+ _mesa_mask_index_span( ctx, n, x, y, indexes );
+ }
+ (*ctx->Driver.WriteCI32Span)( ctx, n, x, y, indexes, mask );
+ }
+ }
+ else {
+ /* same color index for all pixels */
+ ASSERT(!ctx->Color.IndexLogicOpEnabled);
+ ASSERT(ctx->Color.IndexMask == 0xffffffff);
+ if (ctx->RasterMask & MULTI_DRAW_BIT) {
+ /* draw to zero or two or more buffers */
+ GLuint indexes[MAX_WIDTH];
+ for (i=0;i<n;i++)
+ indexes[i] = index;
+ multi_write_index_span( ctx, n, x, y, indexes, mask );
+ }
+ else {
+ /* normal situation: draw to exactly one buffer */
+ (*ctx->Driver.WriteMonoCISpan)( ctx, n, x, y, mask );
+ }
+ }
+}
+
+
+
+/*
+ * Draw to more than one RGBA color buffer (or none).
+ */
+static void multi_write_rgba_span( GLcontext *ctx, GLuint n,
+ GLint x, GLint y, CONST GLchan rgba[][4],
+ const GLubyte mask[] )
+{
+ const GLuint colorMask = *((GLuint *) ctx->Color.ColorMask);
+ GLuint bufferBit;
+
+ if (ctx->Color.DrawBuffer == GL_NONE)
+ return;
+
+ /* loop over four possible dest color buffers */
+ for (bufferBit = 1; bufferBit <= 8; bufferBit = bufferBit << 1) {
+ if (bufferBit & ctx->Color.DrawDestMask) {
+ GLchan rgbaTmp[MAX_WIDTH][4];
+ ASSERT(n < MAX_WIDTH);
+
+ if (bufferBit == FRONT_LEFT_BIT) {
+ (void) (*ctx->Driver.SetDrawBuffer)( ctx, GL_FRONT_LEFT);
+ ctx->DrawBuffer->Alpha = ctx->DrawBuffer->FrontLeftAlpha;
+ }
+ else if (bufferBit == FRONT_RIGHT_BIT) {
+ (void) (*ctx->Driver.SetDrawBuffer)( ctx, GL_FRONT_RIGHT);
+ ctx->DrawBuffer->Alpha = ctx->DrawBuffer->FrontRightAlpha;
+ }
+ else if (bufferBit == BACK_LEFT_BIT) {
+ (void) (*ctx->Driver.SetDrawBuffer)( ctx, GL_BACK_LEFT);
+ ctx->DrawBuffer->Alpha = ctx->DrawBuffer->BackLeftAlpha;
+ }
+ else {
+ (void) (*ctx->Driver.SetDrawBuffer)( ctx, GL_BACK_RIGHT);
+ ctx->DrawBuffer->Alpha = ctx->DrawBuffer->BackRightAlpha;
+ }
+
+ /* make copy of incoming colors */
+ MEMCPY( rgbaTmp, rgba, 4 * n * sizeof(GLchan) );
+
+ if (ctx->Color.ColorLogicOpEnabled) {
+ _mesa_logicop_rgba_span( ctx, n, x, y, rgbaTmp, mask );
+ }
+ else if (ctx->Color.BlendEnabled) {
+ _mesa_blend_span( ctx, n, x, y, rgbaTmp, mask );
+ }
+ if (colorMask == 0x0) {
+ break;
+ }
+ else if (colorMask != 0xffffffff) {
+ _mesa_mask_rgba_span( ctx, n, x, y, rgbaTmp );
+ }
+
+ (*ctx->Driver.WriteRGBASpan)( ctx, n, x, y,
+ (const GLchan (*)[4]) rgbaTmp, mask );
+ if (ctx->RasterMask & ALPHABUF_BIT) {
+ _mesa_write_alpha_span( ctx, n, x, y,
+ (const GLchan (*)[4])rgbaTmp, mask );
+ }
+ }
+ }
+
+ /* restore default dest buffer */
+ (void) (*ctx->Driver.SetDrawBuffer)( ctx, ctx->Color.DriverDrawBuffer );
+}
+
+
+
+void gl_write_rgba_span( GLcontext *ctx,
+ GLuint n, GLint x, GLint y, const GLdepth z[],
+ const GLfixed *fog,
+ GLchan rgbaIn[][4],
+ GLenum primitive )
+{
+ const GLuint modBits = FOG_BIT | BLEND_BIT | MASKING_BIT |
+ LOGIC_OP_BIT | TEXTURE_BIT;
+ GLubyte mask[MAX_WIDTH];
+ GLboolean write_all = GL_TRUE;
+ GLchan rgbaBackup[MAX_WIDTH][4];
+ GLchan (*rgba)[4];
+ const GLubyte *Null = 0;
+
+ /* init mask to 1's (all pixels are to be written) */
+ MEMSET(mask, 1, n);
+
+ if ((ctx->RasterMask & WINCLIP_BIT) || primitive==GL_BITMAP) {
+ if (clip_span( ctx,n,x,y,mask)==0) {
+ return;
+ }
+ write_all = GL_FALSE;
+ }
+
+ if ((primitive==GL_BITMAP && (ctx->RasterMask & modBits))
+ || (ctx->RasterMask & MULTI_DRAW_BIT)) {
+ /* must make a copy of the colors since they may be modified */
+ MEMCPY( rgbaBackup, rgbaIn, 4 * n * sizeof(GLchan) );
+ rgba = rgbaBackup;
+ }
+ else {
+ rgba = rgbaIn;
+ }
+
+ /* Per-pixel fog */
+ if (ctx->Fog.Enabled) {
+ if (fog && ctx->Hint.Fog != GL_NICEST)
+ _mesa_fog_rgba_pixels( ctx, n, fog, rgba );
+ else
+ _mesa_depth_fog_rgba_pixels( ctx, n, z, rgba );
+ }
+
+ /* Do the scissor test */
+ if (ctx->Scissor.Enabled) {
+ if (gl_scissor_span( ctx, n, x, y, mask )==0) {
+ return;
+ }
+ write_all = GL_FALSE;
+ }
+
+ /* Polygon Stippling */
+ if (ctx->Polygon.StippleFlag && primitive==GL_POLYGON) {
+ stipple_polygon_span( ctx, n, x, y, mask );
+ write_all = GL_FALSE;
+ }
+
+ /* Do the alpha test */
+ if (ctx->Color.AlphaEnabled) {
+ if (_mesa_alpha_test( ctx, n, (const GLchan (*)[4]) rgba, mask )==0) {
+ return;
+ }
+ write_all = GL_FALSE;
+ }
+
+ if (ctx->Stencil.Enabled) {
+ /* first stencil test */
+ if (_mesa_stencil_and_ztest_span(ctx, n, x, y, z, mask) == GL_FALSE) {
+ return;
+ }
+ write_all = GL_FALSE;
+ }
+ else if (ctx->Depth.Test) {
+ /* regular depth testing */
+ GLuint m = _mesa_depth_test_span( ctx, n, x, y, z, mask );
+ if (m==0) {
+ return;
+ }
+ if (m<n) {
+ write_all = GL_FALSE;
+ }
+ }
+
+ /* if we get here, something passed the depth test */
+ ctx->OcclusionResult = GL_TRUE;
+
+ if (ctx->RasterMask & MULTI_DRAW_BIT) {
+ multi_write_rgba_span( ctx, n, x, y, (const GLchan (*)[4]) rgba, mask );
+ }
+ else {
+ /* normal: write to exactly one buffer */
+ /* logic op or blending */
+ const GLuint colorMask = *((GLuint *) ctx->Color.ColorMask);
+
+ if (ctx->Color.ColorLogicOpEnabled) {
+ _mesa_logicop_rgba_span( ctx, n, x, y, rgba, mask );
+ }
+ else if (ctx->Color.BlendEnabled) {
+ _mesa_blend_span( ctx, n, x, y, rgba, mask );
+ }
+
+ /* Color component masking */
+ if (colorMask == 0x0) {
+ return;
+ }
+ else if (colorMask != 0xffffffff) {
+ _mesa_mask_rgba_span( ctx, n, x, y, rgba );
+ }
+
+ /* write pixels */
+ (*ctx->Driver.WriteRGBASpan)( ctx, n, x, y,
+ (const GLchan (*)[4]) rgba,
+ write_all ? Null : mask );
+
+ if (ctx->RasterMask & ALPHABUF_BIT) {
+ _mesa_write_alpha_span( ctx, n, x, y,
+ (const GLchan (*)[4]) rgba,
+ write_all ? Null : mask );
+ }
+
+ }
+}
+
+
+
+/*
+ * Write a horizontal span of color pixels to the frame buffer.
+ * The color is initially constant for the whole span.
+ * Alpha-testing, stenciling, depth-testing, and blending are done as needed.
+ * Input: n - number of pixels in the span
+ * x, y - location of leftmost pixel in the span
+ * z - array of [n] z-values
+ * r, g, b, a - the color of the pixels
+ * primitive - either GL_POINT, GL_LINE, GL_POLYGON or GL_BITMAP.
+ */
+void gl_write_monocolor_span( GLcontext *ctx,
+ GLuint n, GLint x, GLint y, const GLdepth z[],
+ const GLfixed fog[],
+ const GLchan color[4],
+ GLenum primitive )
+{
+ const GLuint colorMask = *((GLuint *) ctx->Color.ColorMask);
+ GLuint i;
+ GLubyte mask[MAX_WIDTH];
+ GLboolean write_all = GL_TRUE;
+ GLchan rgba[MAX_WIDTH][4];
+ const GLubyte *Null = 0;
+
+ /* init mask to 1's (all pixels are to be written) */
+ MEMSET(mask, 1, n);
+
+ if ((ctx->RasterMask & WINCLIP_BIT) || primitive==GL_BITMAP) {
+ if (clip_span( ctx,n,x,y,mask)==0) {
+ return;
+ }
+ write_all = GL_FALSE;
+ }
+
+ /* Do the scissor test */
+ if (ctx->Scissor.Enabled) {
+ if (gl_scissor_span( ctx, n, x, y, mask )==0) {
+ return;
+ }
+ write_all = GL_FALSE;
+ }
+
+ /* Polygon Stippling */
+ if (ctx->Polygon.StippleFlag && primitive==GL_POLYGON) {
+ stipple_polygon_span( ctx, n, x, y, mask );
+ write_all = GL_FALSE;
+ }
+
+ /* Do the alpha test */
+ if (ctx->Color.AlphaEnabled) {
+ for (i=0;i<n;i++) {
+ rgba[i][ACOMP] = color[ACOMP];
+ }
+ if (_mesa_alpha_test( ctx, n, (const GLchan (*)[4])rgba, mask )==0) {
+ return;
+ }
+ write_all = GL_FALSE;
+ }
+
+ if (ctx->Stencil.Enabled) {
+ /* first stencil test */
+ if (_mesa_stencil_and_ztest_span(ctx, n, x, y, z, mask) == GL_FALSE) {
+ return;
+ }
+ write_all = GL_FALSE;
+ }
+ else if (ctx->Depth.Test) {
+ /* regular depth testing */
+ GLuint m = _mesa_depth_test_span( ctx, n, x, y, z, mask );
+ if (m==0) {
+ return;
+ }
+ if (m<n) {
+ write_all = GL_FALSE;
+ }
+ }
+
+ /* if we get here, something passed the depth test */
+ ctx->OcclusionResult = GL_TRUE;
+
+ if (ctx->Color.DrawBuffer == GL_NONE) {
+ /* write no pixels */
+ return;
+ }
+
+ if (ctx->Color.ColorLogicOpEnabled || colorMask != 0xffffffff ||
+ (ctx->RasterMask & (BLEND_BIT | FOG_BIT))) {
+ /* assign same color to each pixel */
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ COPY_CHAN4(rgba[i], color);
+ }
+ }
+
+ /* Per-pixel fog */
+ if (ctx->Fog.Enabled) {
+ if (fog && ctx->Hint.Fog != GL_NICEST)
+ _mesa_fog_rgba_pixels( ctx, n, fog, rgba );
+ else
+ _mesa_depth_fog_rgba_pixels( ctx, n, z, rgba );
+ }
+
+ if (ctx->RasterMask & MULTI_DRAW_BIT) {
+ multi_write_rgba_span( ctx, n, x, y,
+ (const GLchan (*)[4]) rgba, mask );
+ }
+ else {
+ /* normal: write to exactly one buffer */
+ if (ctx->Color.ColorLogicOpEnabled) {
+ _mesa_logicop_rgba_span( ctx, n, x, y, rgba, mask );
+ }
+ else if (ctx->Color.BlendEnabled) {
+ _mesa_blend_span( ctx, n, x, y, rgba, mask );
+ }
+
+ /* Color component masking */
+ if (colorMask == 0x0) {
+ return;
+ }
+ else if (colorMask != 0xffffffff) {
+ _mesa_mask_rgba_span( ctx, n, x, y, rgba );
+ }
+
+ /* write pixels */
+ (*ctx->Driver.WriteRGBASpan)( ctx, n, x, y,
+ (const GLchan (*)[4]) rgba,
+ write_all ? Null : mask );
+ if (ctx->RasterMask & ALPHABUF_BIT) {
+ _mesa_write_alpha_span( ctx, n, x, y,
+ (const GLchan (*)[4]) rgba,
+ write_all ? Null : mask );
+ }
+ }
+ }
+ else {
+ /* same color for all pixels */
+ ASSERT(!ctx->Color.BlendEnabled);
+ ASSERT(!ctx->Color.ColorLogicOpEnabled);
+
+ if (ctx->RasterMask & MULTI_DRAW_BIT) {
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ COPY_CHAN4(rgba[i], color);
+ }
+ }
+ multi_write_rgba_span( ctx, n, x, y,
+ (const GLchan (*)[4]) rgba, mask );
+ }
+ else {
+ (*ctx->Driver.WriteMonoRGBASpan)( ctx, n, x, y, mask );
+ if (ctx->RasterMask & ALPHABUF_BIT) {
+ _mesa_write_mono_alpha_span( ctx, n, x, y, (GLchan) color[ACOMP],
+ write_all ? Null : mask );
+ }
+ }
+ }
+}
+
+
+
+/*
+ * Add specular color to base color. This is used only when
+ * GL_LIGHT_MODEL_COLOR_CONTROL = GL_SEPARATE_SPECULAR_COLOR.
+ */
+static void add_colors(GLuint n, GLchan rgba[][4], CONST GLchan specular[][4] )
+{
+ GLuint i;
+ for (i=0; i<n; i++) {
+ GLint r = rgba[i][RCOMP] + specular[i][RCOMP];
+ GLint g = rgba[i][GCOMP] + specular[i][GCOMP];
+ GLint b = rgba[i][BCOMP] + specular[i][BCOMP];
+ rgba[i][RCOMP] = (GLchan) MIN2(r, CHAN_MAX);
+ rgba[i][GCOMP] = (GLchan) MIN2(g, CHAN_MAX);
+ rgba[i][BCOMP] = (GLchan) MIN2(b, CHAN_MAX);
+ }
+}
+
+
+/*
+ * Write a horizontal span of textured pixels to the frame buffer.
+ * The color of each pixel is different.
+ * Alpha-testing, stenciling, depth-testing, and blending are done
+ * as needed.
+ * Input: n - number of pixels in the span
+ * x, y - location of leftmost pixel in the span
+ * z - array of [n] z-values
+ * s, t - array of (s,t) texture coordinates for each pixel
+ * lambda - array of texture lambda values
+ * rgba - array of [n] color components
+ * primitive - either GL_POINT, GL_LINE, GL_POLYGON or GL_BITMAP.
+ */
+void gl_write_texture_span( GLcontext *ctx,
+ GLuint n, GLint x, GLint y, const GLdepth z[],
+ const GLfixed fog[],
+ const GLfloat s[], const GLfloat t[],
+ const GLfloat u[], GLfloat lambda[],
+ GLchan rgbaIn[][4], CONST GLchan spec[][4],
+ GLenum primitive )
+{
+ const GLuint colorMask = *((GLuint *) ctx->Color.ColorMask);
+ GLubyte mask[MAX_WIDTH];
+ GLboolean write_all = GL_TRUE;
+ GLchan rgbaBackup[MAX_WIDTH][4];
+ GLchan (*rgba)[4]; /* points to either rgbaIn or rgbaBackup */
+ const GLubyte *Null = 0;
+
+ /* init mask to 1's (all pixels are to be written) */
+ MEMSET(mask, 1, n);
+
+ if ((ctx->RasterMask & WINCLIP_BIT) || primitive==GL_BITMAP) {
+ if (clip_span(ctx, n, x, y, mask)==0) {
+ return;
+ }
+ write_all = GL_FALSE;
+ }
+
+
+ if (primitive==GL_BITMAP || (ctx->RasterMask & MULTI_DRAW_BIT)) {
+ /* must make a copy of the colors since they may be modified */
+ MEMCPY(rgbaBackup, rgbaIn, 4 * n * sizeof(GLchan));
+ rgba = rgbaBackup;
+ }
+ else {
+ rgba = rgbaIn;
+ }
+
+ /* Texture */
+ ASSERT(ctx->Texture.ReallyEnabled);
+ gl_texture_pixels( ctx, 0, n, s, t, u, lambda, rgba, rgba );
+
+ /* Add base and specular colors */
+ if (spec && ctx->Light.Enabled
+ && ctx->Light.Model.ColorControl == GL_SEPARATE_SPECULAR_COLOR)
+ add_colors( n, rgba, spec ); /* rgba = rgba + spec */
+
+ /* Per-pixel fog */
+ if (ctx->Fog.Enabled) {
+ if (fog && ctx->Hint.Fog != GL_NICEST)
+ _mesa_fog_rgba_pixels( ctx, n, fog, rgba );
+ else
+ _mesa_depth_fog_rgba_pixels( ctx, n, z, rgba );
+ }
+
+ /* Do the scissor test */
+ if (ctx->Scissor.Enabled) {
+ if (gl_scissor_span( ctx, n, x, y, mask )==0) {
+ return;
+ }
+ write_all = GL_FALSE;
+ }
+
+ /* Polygon Stippling */
+ if (ctx->Polygon.StippleFlag && primitive==GL_POLYGON) {
+ stipple_polygon_span( ctx, n, x, y, mask );
+ write_all = GL_FALSE;
+ }
+
+ /* Do the alpha test */
+ if (ctx->Color.AlphaEnabled) {
+ if (_mesa_alpha_test( ctx, n, (const GLchan (*)[4]) rgba, mask )==0) {
+ return;
+ }
+ write_all = GL_FALSE;
+ }
+
+ if (ctx->Stencil.Enabled) {
+ /* first stencil test */
+ if (_mesa_stencil_and_ztest_span(ctx, n, x, y, z, mask) == GL_FALSE) {
+ return;
+ }
+ write_all = GL_FALSE;
+ }
+ else if (ctx->Depth.Test) {
+ /* regular depth testing */
+ GLuint m = _mesa_depth_test_span( ctx, n, x, y, z, mask );
+ if (m==0) {
+ return;
+ }
+ if (m<n) {
+ write_all = GL_FALSE;
+ }
+ }
+
+ /* if we get here, something passed the depth test */
+ ctx->OcclusionResult = GL_TRUE;
+
+ if (ctx->RasterMask & MULTI_DRAW_BIT) {
+ multi_write_rgba_span( ctx, n, x, y, (const GLchan (*)[4]) rgba, mask );
+ }
+ else {
+ /* normal: write to exactly one buffer */
+ if (ctx->Color.ColorLogicOpEnabled) {
+ _mesa_logicop_rgba_span( ctx, n, x, y, rgba, mask );
+ }
+ else if (ctx->Color.BlendEnabled) {
+ _mesa_blend_span( ctx, n, x, y, rgba, mask );
+ }
+ if (colorMask == 0x0) {
+ return;
+ }
+ else if (colorMask != 0xffffffff) {
+ _mesa_mask_rgba_span( ctx, n, x, y, rgba );
+ }
+
+ (*ctx->Driver.WriteRGBASpan)( ctx, n, x, y, (const GLchan (*)[4])rgba,
+ write_all ? Null : mask );
+ if (ctx->RasterMask & ALPHABUF_BIT) {
+ _mesa_write_alpha_span( ctx, n, x, y, (const GLchan (*)[4]) rgba,
+ write_all ? Null : mask );
+ }
+ }
+}
+
+
+
+/*
+ * As above but perform multiple stages of texture application.
+ */
+void
+gl_write_multitexture_span( GLcontext *ctx,
+ GLuint n, GLint x, GLint y,
+ const GLdepth z[],
+ const GLfixed fog[],
+ CONST GLfloat s[MAX_TEXTURE_UNITS][MAX_WIDTH],
+ CONST GLfloat t[MAX_TEXTURE_UNITS][MAX_WIDTH],
+ CONST GLfloat u[MAX_TEXTURE_UNITS][MAX_WIDTH],
+ GLfloat lambda[][MAX_WIDTH],
+ GLchan rgbaIn[MAX_TEXTURE_UNITS][4],
+ CONST GLchan spec[MAX_TEXTURE_UNITS][4],
+ GLenum primitive )
+{
+ GLubyte mask[MAX_WIDTH];
+ GLboolean write_all = GL_TRUE;
+ GLchan rgbaBackup[MAX_WIDTH][4];
+ GLchan (*rgba)[4]; /* points to either rgbaIn or rgbaBackup */
+ GLuint i;
+ const GLubyte *Null = 0;
+ const GLuint texUnits = ctx->Const.MaxTextureUnits;
+
+ /* init mask to 1's (all pixels are to be written) */
+ MEMSET(mask, 1, n);
+
+ if ((ctx->RasterMask & WINCLIP_BIT) || primitive==GL_BITMAP) {
+ if (clip_span(ctx, n, x, y, mask)==0) {
+ return;
+ }
+ write_all = GL_FALSE;
+ }
+
+
+ if (primitive==GL_BITMAP || (ctx->RasterMask & MULTI_DRAW_BIT)
+ || texUnits > 1) {
+ /* must make a copy of the colors since they may be modified */
+ MEMCPY(rgbaBackup, rgbaIn, 4 * n * sizeof(GLchan));
+ rgba = rgbaBackup;
+ }
+ else {
+ rgba = rgbaIn;
+ }
+
+ /* Texture */
+ ASSERT(ctx->Texture.ReallyEnabled);
+ for (i = 0; i < texUnits; i++)
+ gl_texture_pixels( ctx, i, n, s[i], t[i], u[i], lambda[i], rgbaIn, rgba );
+
+ /* Add base and specular colors */
+ if (spec && ctx->Light.Enabled
+ && ctx->Light.Model.ColorControl == GL_SEPARATE_SPECULAR_COLOR)
+ add_colors( n, rgba, spec ); /* rgba = rgba + spec */
+
+ /* Per-pixel fog */
+ if (ctx->Fog.Enabled) {
+ if (fog && ctx->Hint.Fog != GL_NICEST)
+ _mesa_fog_rgba_pixels( ctx, n, fog, rgba );
+ else
+ _mesa_depth_fog_rgba_pixels( ctx, n, z, rgba );
+ }
+
+ /* Do the scissor test */
+ if (ctx->Scissor.Enabled) {
+ if (gl_scissor_span( ctx, n, x, y, mask )==0) {
+ return;
+ }
+ write_all = GL_FALSE;
+ }
+
+ /* Polygon Stippling */
+ if (ctx->Polygon.StippleFlag && primitive==GL_POLYGON) {
+ stipple_polygon_span( ctx, n, x, y, mask );
+ write_all = GL_FALSE;
+ }
+
+ /* Do the alpha test */
+ if (ctx->Color.AlphaEnabled) {
+ if (_mesa_alpha_test( ctx, n, (const GLchan (*)[4])rgba, mask )==0) {
+ return;
+ }
+ write_all = GL_FALSE;
+ }
+
+ if (ctx->Stencil.Enabled) {
+ /* first stencil test */
+ if (_mesa_stencil_and_ztest_span(ctx, n, x, y, z, mask) == GL_FALSE) {
+ return;
+ }
+ write_all = GL_FALSE;
+ }
+ else if (ctx->Depth.Test) {
+ /* regular depth testing */
+ GLuint m = _mesa_depth_test_span( ctx, n, x, y, z, mask );
+ if (m==0) {
+ return;
+ }
+ if (m<n) {
+ write_all = GL_FALSE;
+ }
+ }
+
+ /* if we get here, something passed the depth test */
+ ctx->OcclusionResult = GL_TRUE;
+
+ if (ctx->RasterMask & MULTI_DRAW_BIT) {
+ multi_write_rgba_span( ctx, n, x, y, (const GLchan (*)[4]) rgba, mask );
+ }
+ else {
+ /* normal: write to exactly one buffer */
+ const GLuint colorMask = *((GLuint *) ctx->Color.ColorMask);
+
+ if (ctx->Color.ColorLogicOpEnabled) {
+ _mesa_logicop_rgba_span( ctx, n, x, y, rgba, mask );
+ }
+ else if (ctx->Color.BlendEnabled) {
+ _mesa_blend_span( ctx, n, x, y, rgba, mask );
+ }
+
+ if (colorMask == 0x0) {
+ return;
+ }
+ else if (colorMask != 0xffffffff) {
+ _mesa_mask_rgba_span( ctx, n, x, y, rgba );
+ }
+
+ (*ctx->Driver.WriteRGBASpan)( ctx, n, x, y, (const GLchan (*)[4])rgba, write_all ? Null : mask );
+ if (ctx->RasterMask & ALPHABUF_BIT) {
+ _mesa_write_alpha_span( ctx, n, x, y, (const GLchan (*)[4])rgba,
+ write_all ? Null : mask );
+ }
+ }
+}
+
+
+
+/*
+ * Read RGBA pixels from frame buffer. Clipping will be done to prevent
+ * reading ouside the buffer's boundaries.
+ */
+void gl_read_rgba_span( GLcontext *ctx, GLframebuffer *buffer,
+ GLuint n, GLint x, GLint y,
+ GLchan rgba[][4] )
+{
+ if (y < 0 || y >= buffer->Height
+ || x + (GLint) n < 0 || x >= buffer->Width) {
+ /* completely above, below, or right */
+ /* XXX maybe leave undefined? */
+ BZERO(rgba, 4 * n * sizeof(GLchan));
+ }
+ else {
+ GLint skip, length;
+ if (x < 0) {
+ /* left edge clippping */
+ skip = -x;
+ length = (GLint) n - skip;
+ if (length < 0) {
+ /* completely left of window */
+ return;
+ }
+ if (length > buffer->Width) {
+ length = buffer->Width;
+ }
+ }
+ else if ((GLint) (x + n) > buffer->Width) {
+ /* right edge clipping */
+ skip = 0;
+ length = buffer->Width - x;
+ if (length < 0) {
+ /* completely to right of window */
+ return;
+ }
+ }
+ else {
+ /* no clipping */
+ skip = 0;
+ length = (GLint) n;
+ }
+
+ (*ctx->Driver.ReadRGBASpan)( ctx, length, x + skip, y, rgba + skip );
+ if (buffer->UseSoftwareAlphaBuffers) {
+ _mesa_read_alpha_span( ctx, length, x + skip, y, rgba + skip );
+ }
+ }
+}
+
+
+
+
+/*
+ * Read CI pixels from frame buffer. Clipping will be done to prevent
+ * reading ouside the buffer's boundaries.
+ */
+void gl_read_index_span( GLcontext *ctx, GLframebuffer *buffer,
+ GLuint n, GLint x, GLint y, GLuint indx[] )
+{
+ if (y < 0 || y >= buffer->Height
+ || x + (GLint) n < 0 || x >= buffer->Width) {
+ /* completely above, below, or right */
+ BZERO(indx, n * sizeof(GLuint));
+ }
+ else {
+ GLint skip, length;
+ if (x < 0) {
+ /* left edge clippping */
+ skip = -x;
+ length = (GLint) n - skip;
+ if (length < 0) {
+ /* completely left of window */
+ return;
+ }
+ if (length > buffer->Width) {
+ length = buffer->Width;
+ }
+ }
+ else if ((GLint) (x + n) > buffer->Width) {
+ /* right edge clipping */
+ skip = 0;
+ length = buffer->Width - x;
+ if (length < 0) {
+ /* completely to right of window */
+ return;
+ }
+ }
+ else {
+ /* no clipping */
+ skip = 0;
+ length = (GLint) n;
+ }
+
+ (*ctx->Driver.ReadCI32Span)( ctx, length, skip + x, y, indx + skip );
+ }
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-30 17:10:21 +0000