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-rw-r--r--mesalib/src/mesa/swrast/s_stencil.c2490
1 files changed, 1245 insertions, 1245 deletions
diff --git a/mesalib/src/mesa/swrast/s_stencil.c b/mesalib/src/mesa/swrast/s_stencil.c
index aa74b21ee..999fe3c3f 100644
--- a/mesalib/src/mesa/swrast/s_stencil.c
+++ b/mesalib/src/mesa/swrast/s_stencil.c
@@ -1,1245 +1,1245 @@
-/*
- * Mesa 3-D graphics library
- * Version: 7.1
- *
- * Copyright (C) 1999-2007 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 "main/glheader.h"
-#include "main/context.h"
-#include "main/imports.h"
-
-#include "s_context.h"
-#include "s_depth.h"
-#include "s_stencil.h"
-#include "s_span.h"
-
-
-
-/* Stencil Logic:
-
-IF stencil test fails THEN
- Apply fail-op to stencil value
- Don't write the pixel (RGBA,Z)
-ELSE
- IF doing depth test && depth test fails THEN
- Apply zfail-op to stencil value
- Write RGBA and Z to appropriate buffers
- ELSE
- Apply zpass-op to stencil value
-ENDIF
-
-*/
-
-
-/**
- * Apply the given stencil operator to the array of stencil values.
- * Don't touch stencil[i] if mask[i] is zero.
- * Input: n - size of stencil array
- * oper - the stencil buffer operator
- * face - 0 or 1 for front or back face operation
- * stencil - array of stencil values
- * mask - array [n] of flag: 1=apply operator, 0=don't apply operator
- * Output: stencil - modified values
- */
-static void
-apply_stencil_op( const GLcontext *ctx, GLenum oper, GLuint face,
- GLuint n, GLstencil stencil[], const GLubyte mask[] )
-{
- const GLstencil ref = ctx->Stencil.Ref[face];
- const GLstencil wrtmask = ctx->Stencil.WriteMask[face];
- const GLstencil invmask = (GLstencil) (~wrtmask);
- const GLstencil stencilMax = (1 << ctx->DrawBuffer->Visual.stencilBits) - 1;
- GLuint i;
-
- switch (oper) {
- case GL_KEEP:
- /* do nothing */
- break;
- case GL_ZERO:
- if (invmask==0) {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- stencil[i] = 0;
- }
- }
- }
- else {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- stencil[i] = (GLstencil) (stencil[i] & invmask);
- }
- }
- }
- break;
- case GL_REPLACE:
- if (invmask==0) {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- stencil[i] = ref;
- }
- }
- }
- else {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLstencil s = stencil[i];
- stencil[i] = (GLstencil) ((invmask & s ) | (wrtmask & ref));
- }
- }
- }
- break;
- case GL_INCR:
- if (invmask==0) {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLstencil s = stencil[i];
- if (s < stencilMax) {
- stencil[i] = (GLstencil) (s+1);
- }
- }
- }
- }
- else {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- /* VERIFY logic of adding 1 to a write-masked value */
- GLstencil s = stencil[i];
- if (s < stencilMax) {
- stencil[i] = (GLstencil) ((invmask & s) | (wrtmask & (s+1)));
- }
- }
- }
- }
- break;
- case GL_DECR:
- if (invmask==0) {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLstencil s = stencil[i];
- if (s>0) {
- stencil[i] = (GLstencil) (s-1);
- }
- }
- }
- }
- else {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- /* VERIFY logic of subtracting 1 to a write-masked value */
- GLstencil s = stencil[i];
- if (s>0) {
- stencil[i] = (GLstencil) ((invmask & s) | (wrtmask & (s-1)));
- }
- }
- }
- }
- break;
- case GL_INCR_WRAP_EXT:
- if (invmask==0) {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- stencil[i]++;
- }
- }
- }
- else {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLstencil s = stencil[i];
- stencil[i] = (GLstencil) ((invmask & s) | (wrtmask & (s+1)));
- }
- }
- }
- break;
- case GL_DECR_WRAP_EXT:
- if (invmask==0) {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- stencil[i]--;
- }
- }
- }
- else {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLstencil s = stencil[i];
- stencil[i] = (GLstencil) ((invmask & s) | (wrtmask & (s-1)));
- }
- }
- }
- break;
- case GL_INVERT:
- if (invmask==0) {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLstencil s = stencil[i];
- stencil[i] = (GLstencil) ~s;
- }
- }
- }
- else {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLstencil s = stencil[i];
- stencil[i] = (GLstencil) ((invmask & s) | (wrtmask & ~s));
- }
- }
- }
- break;
- default:
- _mesa_problem(ctx, "Bad stencil op in apply_stencil_op");
- }
-}
-
-
-
-
-/**
- * Apply stencil test to an array of stencil values (before depth buffering).
- * Input: face - 0 or 1 for front or back-face polygons
- * n - number of pixels in the array
- * stencil - array of [n] stencil values
- * mask - array [n] of flag: 0=skip the pixel, 1=stencil the pixel
- * Output: mask - pixels which fail the stencil test will have their
- * mask flag set to 0.
- * stencil - updated stencil values (where the test passed)
- * Return: GL_FALSE = all pixels failed, GL_TRUE = zero or more pixels passed.
- */
-static GLboolean
-do_stencil_test( GLcontext *ctx, GLuint face, GLuint n, GLstencil stencil[],
- GLubyte mask[] )
-{
- GLubyte fail[MAX_WIDTH];
- GLboolean allfail = GL_FALSE;
- GLuint i;
- const GLuint valueMask = ctx->Stencil.ValueMask[face];
- const GLstencil r = (GLstencil) (ctx->Stencil.Ref[face] & valueMask);
- GLstencil s;
-
- ASSERT(n <= MAX_WIDTH);
-
- /*
- * Perform stencil test. The results of this operation are stored
- * in the fail[] array:
- * IF fail[i] is non-zero THEN
- * the stencil fail operator is to be applied
- * ELSE
- * the stencil fail operator is not to be applied
- * ENDIF
- */
- switch (ctx->Stencil.Function[face]) {
- case GL_NEVER:
- /* never pass; always fail */
- for (i=0;i<n;i++) {
- if (mask[i]) {
- mask[i] = 0;
- fail[i] = 1;
- }
- else {
- fail[i] = 0;
- }
- }
- allfail = GL_TRUE;
- break;
- case GL_LESS:
- for (i=0;i<n;i++) {
- if (mask[i]) {
- s = (GLstencil) (stencil[i] & valueMask);
- if (r < s) {
- /* passed */
- fail[i] = 0;
- }
- else {
- fail[i] = 1;
- mask[i] = 0;
- }
- }
- else {
- fail[i] = 0;
- }
- }
- break;
- case GL_LEQUAL:
- for (i=0;i<n;i++) {
- if (mask[i]) {
- s = (GLstencil) (stencil[i] & valueMask);
- if (r <= s) {
- /* pass */
- fail[i] = 0;
- }
- else {
- fail[i] = 1;
- mask[i] = 0;
- }
- }
- else {
- fail[i] = 0;
- }
- }
- break;
- case GL_GREATER:
- for (i=0;i<n;i++) {
- if (mask[i]) {
- s = (GLstencil) (stencil[i] & valueMask);
- if (r > s) {
- /* passed */
- fail[i] = 0;
- }
- else {
- fail[i] = 1;
- mask[i] = 0;
- }
- }
- else {
- fail[i] = 0;
- }
- }
- break;
- case GL_GEQUAL:
- for (i=0;i<n;i++) {
- if (mask[i]) {
- s = (GLstencil) (stencil[i] & valueMask);
- if (r >= s) {
- /* passed */
- fail[i] = 0;
- }
- else {
- fail[i] = 1;
- mask[i] = 0;
- }
- }
- else {
- fail[i] = 0;
- }
- }
- break;
- case GL_EQUAL:
- for (i=0;i<n;i++) {
- if (mask[i]) {
- s = (GLstencil) (stencil[i] & valueMask);
- if (r == s) {
- /* passed */
- fail[i] = 0;
- }
- else {
- fail[i] = 1;
- mask[i] = 0;
- }
- }
- else {
- fail[i] = 0;
- }
- }
- break;
- case GL_NOTEQUAL:
- for (i=0;i<n;i++) {
- if (mask[i]) {
- s = (GLstencil) (stencil[i] & valueMask);
- if (r != s) {
- /* passed */
- fail[i] = 0;
- }
- else {
- fail[i] = 1;
- mask[i] = 0;
- }
- }
- else {
- fail[i] = 0;
- }
- }
- break;
- case GL_ALWAYS:
- /* always pass */
- for (i=0;i<n;i++) {
- fail[i] = 0;
- }
- break;
- default:
- _mesa_problem(ctx, "Bad stencil func in gl_stencil_span");
- return 0;
- }
-
- if (ctx->Stencil.FailFunc[face] != GL_KEEP) {
- apply_stencil_op( ctx, ctx->Stencil.FailFunc[face], face, n, stencil, fail );
- }
-
- return !allfail;
-}
-
-
-/**
- * Compute the zpass/zfail masks by comparing the pre- and post-depth test
- * masks.
- */
-static INLINE void
-compute_pass_fail_masks(GLuint n, const GLubyte origMask[],
- const GLubyte newMask[],
- GLubyte passMask[], GLubyte failMask[])
-{
- GLuint i;
- for (i = 0; i < n; i++) {
- ASSERT(newMask[i] == 0 || newMask[i] == 1);
- passMask[i] = origMask[i] & newMask[i];
- failMask[i] = origMask[i] & (newMask[i] ^ 1);
- }
-}
-
-
-/**
- * Apply stencil and depth testing to the span of pixels.
- * Both software and hardware stencil buffers are acceptable.
- * Input: n - number of pixels in the span
- * x, y - location of leftmost pixel in span
- * z - array [n] of z values
- * mask - array [n] of flags (1=test this pixel, 0=skip the pixel)
- * Output: mask - array [n] of flags (1=stencil and depth test passed)
- * Return: GL_FALSE - all fragments failed the testing
- * GL_TRUE - one or more fragments passed the testing
- *
- */
-static GLboolean
-stencil_and_ztest_span(GLcontext *ctx, SWspan *span, GLuint face)
-{
- struct gl_framebuffer *fb = ctx->DrawBuffer;
- struct gl_renderbuffer *rb = fb->_StencilBuffer;
- GLstencil stencilRow[MAX_WIDTH];
- GLstencil *stencil;
- const GLuint n = span->end;
- const GLint x = span->x;
- const GLint y = span->y;
- GLubyte *mask = span->array->mask;
-
- ASSERT((span->arrayMask & SPAN_XY) == 0);
- ASSERT(ctx->Stencil.Enabled);
- ASSERT(n <= MAX_WIDTH);
-#ifdef DEBUG
- if (ctx->Depth.Test) {
- ASSERT(span->arrayMask & SPAN_Z);
- }
-#endif
-
- stencil = (GLstencil *) rb->GetPointer(ctx, rb, x, y);
- if (!stencil) {
- rb->GetRow(ctx, rb, n, x, y, stencilRow);
- stencil = stencilRow;
- }
-
- /*
- * Apply the stencil test to the fragments.
- * failMask[i] is 1 if the stencil test failed.
- */
- if (do_stencil_test( ctx, face, n, stencil, mask ) == GL_FALSE) {
- /* all fragments failed the stencil test, we're done. */
- span->writeAll = GL_FALSE;
- if (!rb->GetPointer(ctx, rb, 0, 0)) {
- /* put updated stencil values into buffer */
- rb->PutRow(ctx, rb, n, x, y, stencil, NULL);
- }
- return GL_FALSE;
- }
-
- /*
- * Some fragments passed the stencil test, apply depth test to them
- * and apply Zpass and Zfail stencil ops.
- */
- if (ctx->Depth.Test == GL_FALSE) {
- /*
- * No depth buffer, just apply zpass stencil function to active pixels.
- */
- apply_stencil_op( ctx, ctx->Stencil.ZPassFunc[face], face, n, stencil, mask );
- }
- else {
- /*
- * Perform depth buffering, then apply zpass or zfail stencil function.
- */
- GLubyte passMask[MAX_WIDTH], failMask[MAX_WIDTH], origMask[MAX_WIDTH];
-
- /* save the current mask bits */
- memcpy(origMask, mask, n * sizeof(GLubyte));
-
- /* apply the depth test */
- _swrast_depth_test_span(ctx, span);
-
- compute_pass_fail_masks(n, origMask, mask, passMask, failMask);
-
- /* apply the pass and fail operations */
- if (ctx->Stencil.ZFailFunc[face] != GL_KEEP) {
- apply_stencil_op( ctx, ctx->Stencil.ZFailFunc[face], face,
- n, stencil, failMask );
- }
- if (ctx->Stencil.ZPassFunc[face] != GL_KEEP) {
- apply_stencil_op( ctx, ctx->Stencil.ZPassFunc[face], face,
- n, stencil, passMask );
- }
- }
-
- /*
- * Write updated stencil values back into hardware stencil buffer.
- */
- if (!rb->GetPointer(ctx, rb, 0, 0)) {
- rb->PutRow(ctx, rb, n, x, y, stencil, NULL);
- }
-
- span->writeAll = GL_FALSE;
-
- return GL_TRUE; /* one or more fragments passed both tests */
-}
-
-
-
-/*
- * Return the address of a stencil buffer value given the window coords:
- */
-#define STENCIL_ADDRESS(X, Y) (stencilStart + (Y) * stride + (X))
-
-
-
-/**
- * Apply the given stencil operator for each pixel in the array whose
- * mask flag is set.
- * \note This is for software stencil buffers only.
- * Input: n - number of pixels in the span
- * x, y - array of [n] pixels
- * operator - the stencil buffer operator
- * mask - array [n] of flag: 1=apply operator, 0=don't apply operator
- */
-static void
-apply_stencil_op_to_pixels( GLcontext *ctx,
- GLuint n, const GLint x[], const GLint y[],
- GLenum oper, GLuint face, const GLubyte mask[] )
-{
- struct gl_framebuffer *fb = ctx->DrawBuffer;
- struct gl_renderbuffer *rb = fb->_StencilBuffer;
- const GLstencil stencilMax = (1 << fb->Visual.stencilBits) - 1;
- const GLstencil ref = ctx->Stencil.Ref[face];
- const GLstencil wrtmask = ctx->Stencil.WriteMask[face];
- const GLstencil invmask = (GLstencil) (~wrtmask);
- GLuint i;
- GLstencil *stencilStart = (GLubyte *) rb->Data;
- const GLuint stride = rb->Width;
-
- ASSERT(rb->GetPointer(ctx, rb, 0, 0));
- ASSERT(sizeof(GLstencil) == 1);
-
- switch (oper) {
- case GL_KEEP:
- /* do nothing */
- break;
- case GL_ZERO:
- if (invmask==0) {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] );
- *sptr = 0;
- }
- }
- }
- else {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] );
- *sptr = (GLstencil) (invmask & *sptr);
- }
- }
- }
- break;
- case GL_REPLACE:
- if (invmask==0) {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] );
- *sptr = ref;
- }
- }
- }
- else {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] );
- *sptr = (GLstencil) ((invmask & *sptr ) | (wrtmask & ref));
- }
- }
- }
- break;
- case GL_INCR:
- if (invmask==0) {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] );
- if (*sptr < stencilMax) {
- *sptr = (GLstencil) (*sptr + 1);
- }
- }
- }
- }
- else {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] );
- if (*sptr < stencilMax) {
- *sptr = (GLstencil) ((invmask & *sptr) | (wrtmask & (*sptr+1)));
- }
- }
- }
- }
- break;
- case GL_DECR:
- if (invmask==0) {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] );
- if (*sptr>0) {
- *sptr = (GLstencil) (*sptr - 1);
- }
- }
- }
- }
- else {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] );
- if (*sptr>0) {
- *sptr = (GLstencil) ((invmask & *sptr) | (wrtmask & (*sptr-1)));
- }
- }
- }
- }
- break;
- case GL_INCR_WRAP_EXT:
- if (invmask==0) {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] );
- *sptr = (GLstencil) (*sptr + 1);
- }
- }
- }
- else {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] );
- *sptr = (GLstencil) ((invmask & *sptr) | (wrtmask & (*sptr+1)));
- }
- }
- }
- break;
- case GL_DECR_WRAP_EXT:
- if (invmask==0) {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] );
- *sptr = (GLstencil) (*sptr - 1);
- }
- }
- }
- else {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] );
- *sptr = (GLstencil) ((invmask & *sptr) | (wrtmask & (*sptr-1)));
- }
- }
- }
- break;
- case GL_INVERT:
- if (invmask==0) {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] );
- *sptr = (GLstencil) (~*sptr);
- }
- }
- }
- else {
- for (i=0;i<n;i++) {
- if (mask[i]) {
- GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] );
- *sptr = (GLstencil) ((invmask & *sptr) | (wrtmask & ~*sptr));
- }
- }
- }
- break;
- default:
- _mesa_problem(ctx, "Bad stencilop in apply_stencil_op_to_pixels");
- }
-}
-
-
-
-/**
- * Apply stencil test to an array of pixels before depth buffering.
- *
- * \note Used for software stencil buffer only.
- * Input: n - number of pixels in the span
- * x, y - array of [n] pixels to stencil
- * mask - array [n] of flag: 0=skip the pixel, 1=stencil the pixel
- * Output: mask - pixels which fail the stencil test will have their
- * mask flag set to 0.
- * \return GL_FALSE = all pixels failed, GL_TRUE = zero or more pixels passed.
- */
-static GLboolean
-stencil_test_pixels( GLcontext *ctx, GLuint face, GLuint n,
- const GLint x[], const GLint y[], GLubyte mask[] )
-{
- const struct gl_framebuffer *fb = ctx->DrawBuffer;
- struct gl_renderbuffer *rb = fb->_StencilBuffer;
- GLubyte fail[MAX_WIDTH];
- GLstencil r, s;
- GLuint i;
- GLboolean allfail = GL_FALSE;
- const GLuint valueMask = ctx->Stencil.ValueMask[face];
- const GLstencil *stencilStart = (GLstencil *) rb->Data;
- const GLuint stride = rb->Width;
-
- ASSERT(rb->GetPointer(ctx, rb, 0, 0));
- ASSERT(sizeof(GLstencil) == 1);
-
- /*
- * Perform stencil test. The results of this operation are stored
- * in the fail[] array:
- * IF fail[i] is non-zero THEN
- * the stencil fail operator is to be applied
- * ELSE
- * the stencil fail operator is not to be applied
- * ENDIF
- */
-
- switch (ctx->Stencil.Function[face]) {
- case GL_NEVER:
- /* always fail */
- for (i=0;i<n;i++) {
- if (mask[i]) {
- mask[i] = 0;
- fail[i] = 1;
- }
- else {
- fail[i] = 0;
- }
- }
- allfail = GL_TRUE;
- break;
- case GL_LESS:
- r = (GLstencil) (ctx->Stencil.Ref[face] & valueMask);
- for (i=0;i<n;i++) {
- if (mask[i]) {
- const GLstencil *sptr = STENCIL_ADDRESS(x[i],y[i]);
- s = (GLstencil) (*sptr & valueMask);
- if (r < s) {
- /* passed */
- fail[i] = 0;
- }
- else {
- fail[i] = 1;
- mask[i] = 0;
- }
- }
- else {
- fail[i] = 0;
- }
- }
- break;
- case GL_LEQUAL:
- r = (GLstencil) (ctx->Stencil.Ref[face] & valueMask);
- for (i=0;i<n;i++) {
- if (mask[i]) {
- const GLstencil *sptr = STENCIL_ADDRESS(x[i],y[i]);
- s = (GLstencil) (*sptr & valueMask);
- if (r <= s) {
- /* pass */
- fail[i] = 0;
- }
- else {
- fail[i] = 1;
- mask[i] = 0;
- }
- }
- else {
- fail[i] = 0;
- }
- }
- break;
- case GL_GREATER:
- r = (GLstencil) (ctx->Stencil.Ref[face] & valueMask);
- for (i=0;i<n;i++) {
- if (mask[i]) {
- const GLstencil *sptr = STENCIL_ADDRESS(x[i],y[i]);
- s = (GLstencil) (*sptr & valueMask);
- if (r > s) {
- /* passed */
- fail[i] = 0;
- }
- else {
- fail[i] = 1;
- mask[i] = 0;
- }
- }
- else {
- fail[i] = 0;
- }
- }
- break;
- case GL_GEQUAL:
- r = (GLstencil) (ctx->Stencil.Ref[face] & valueMask);
- for (i=0;i<n;i++) {
- if (mask[i]) {
- const GLstencil *sptr = STENCIL_ADDRESS(x[i],y[i]);
- s = (GLstencil) (*sptr & valueMask);
- if (r >= s) {
- /* passed */
- fail[i] = 0;
- }
- else {
- fail[i] = 1;
- mask[i] = 0;
- }
- }
- else {
- fail[i] = 0;
- }
- }
- break;
- case GL_EQUAL:
- r = (GLstencil) (ctx->Stencil.Ref[face] & valueMask);
- for (i=0;i<n;i++) {
- if (mask[i]) {
- const GLstencil *sptr = STENCIL_ADDRESS(x[i],y[i]);
- s = (GLstencil) (*sptr & valueMask);
- if (r == s) {
- /* passed */
- fail[i] = 0;
- }
- else {
- fail[i] = 1;
- mask[i] = 0;
- }
- }
- else {
- fail[i] = 0;
- }
- }
- break;
- case GL_NOTEQUAL:
- r = (GLstencil) (ctx->Stencil.Ref[face] & valueMask);
- for (i=0;i<n;i++) {
- if (mask[i]) {
- const GLstencil *sptr = STENCIL_ADDRESS(x[i],y[i]);
- s = (GLstencil) (*sptr & valueMask);
- if (r != s) {
- /* passed */
- fail[i] = 0;
- }
- else {
- fail[i] = 1;
- mask[i] = 0;
- }
- }
- else {
- fail[i] = 0;
- }
- }
- break;
- case GL_ALWAYS:
- /* always pass */
- for (i=0;i<n;i++) {
- fail[i] = 0;
- }
- break;
- default:
- _mesa_problem(ctx, "Bad stencil func in gl_stencil_pixels");
- return 0;
- }
-
- if (ctx->Stencil.FailFunc[face] != GL_KEEP) {
- apply_stencil_op_to_pixels( ctx, n, x, y, ctx->Stencil.FailFunc[face],
- face, fail );
- }
-
- return !allfail;
-}
-
-
-
-
-/**
- * Apply stencil and depth testing to an array of pixels.
- * This is used both for software and hardware stencil buffers.
- *
- * The comments in this function are a bit sparse but the code is
- * almost identical to stencil_and_ztest_span(), which is well
- * commented.
- *
- * Input: n - number of pixels in the array
- * x, y - array of [n] pixel positions
- * z - array [n] of z values
- * mask - array [n] of flags (1=test this pixel, 0=skip the pixel)
- * Output: mask - array [n] of flags (1=stencil and depth test passed)
- * Return: GL_FALSE - all fragments failed the testing
- * GL_TRUE - one or more fragments passed the testing
- */
-static GLboolean
-stencil_and_ztest_pixels( GLcontext *ctx, SWspan *span, GLuint face )
-{
- GLubyte passMask[MAX_WIDTH], failMask[MAX_WIDTH], origMask[MAX_WIDTH];
- struct gl_framebuffer *fb = ctx->DrawBuffer;
- struct gl_renderbuffer *rb = fb->_StencilBuffer;
- const GLuint n = span->end;
- const GLint *x = span->array->x;
- const GLint *y = span->array->y;
- GLubyte *mask = span->array->mask;
-
- ASSERT(span->arrayMask & SPAN_XY);
- ASSERT(ctx->Stencil.Enabled);
- ASSERT(n <= MAX_WIDTH);
-
- if (!rb->GetPointer(ctx, rb, 0, 0)) {
- /* No direct access */
- GLstencil stencil[MAX_WIDTH];
-
- ASSERT(rb->DataType == GL_UNSIGNED_BYTE);
- _swrast_get_values(ctx, rb, n, x, y, stencil, sizeof(GLubyte));
-
- memcpy(origMask, mask, n * sizeof(GLubyte));
-
- (void) do_stencil_test(ctx, face, n, stencil, mask);
-
- if (ctx->Depth.Test == GL_FALSE) {
- apply_stencil_op(ctx, ctx->Stencil.ZPassFunc[face], face,
- n, stencil, mask);
- }
- else {
- GLubyte tmpMask[MAX_WIDTH];
- memcpy(tmpMask, mask, n * sizeof(GLubyte));
-
- _swrast_depth_test_span(ctx, span);
-
- compute_pass_fail_masks(n, tmpMask, mask, passMask, failMask);
-
- if (ctx->Stencil.ZFailFunc[face] != GL_KEEP) {
- apply_stencil_op(ctx, ctx->Stencil.ZFailFunc[face], face,
- n, stencil, failMask);
- }
- if (ctx->Stencil.ZPassFunc[face] != GL_KEEP) {
- apply_stencil_op(ctx, ctx->Stencil.ZPassFunc[face], face,
- n, stencil, passMask);
- }
- }
-
- /* Write updated stencil values into hardware stencil buffer */
- rb->PutValues(ctx, rb, n, x, y, stencil, origMask);
-
- return GL_TRUE;
- }
- else {
- /* Direct access to stencil buffer */
-
- if (stencil_test_pixels(ctx, face, n, x, y, mask) == GL_FALSE) {
- /* all fragments failed the stencil test, we're done. */
- return GL_FALSE;
- }
-
- if (ctx->Depth.Test==GL_FALSE) {
- apply_stencil_op_to_pixels(ctx, n, x, y,
- ctx->Stencil.ZPassFunc[face], face, mask);
- }
- else {
- memcpy(origMask, mask, n * sizeof(GLubyte));
-
- _swrast_depth_test_span(ctx, span);
-
- compute_pass_fail_masks(n, origMask, mask, passMask, failMask);
-
- if (ctx->Stencil.ZFailFunc[face] != GL_KEEP) {
- apply_stencil_op_to_pixels(ctx, n, x, y,
- ctx->Stencil.ZFailFunc[face],
- face, failMask);
- }
- if (ctx->Stencil.ZPassFunc[face] != GL_KEEP) {
- apply_stencil_op_to_pixels(ctx, n, x, y,
- ctx->Stencil.ZPassFunc[face],
- face, passMask);
- }
- }
-
- return GL_TRUE; /* one or more fragments passed both tests */
- }
-}
-
-
-/**
- * /return GL_TRUE = one or more fragments passed,
- * GL_FALSE = all fragments failed.
- */
-GLboolean
-_swrast_stencil_and_ztest_span(GLcontext *ctx, SWspan *span)
-{
- const GLuint face = (span->facing == 0) ? 0 : ctx->Stencil._BackFace;
-
- if (span->arrayMask & SPAN_XY)
- return stencil_and_ztest_pixels(ctx, span, face);
- else
- return stencil_and_ztest_span(ctx, span, face);
-}
-
-
-#if 0
-GLuint
-clip_span(GLuint bufferWidth, GLuint bufferHeight,
- GLint x, GLint y, GLuint *count)
-{
- GLuint n = *count;
- GLuint skipPixels = 0;
-
- if (y < 0 || y >= bufferHeight || x + n <= 0 || x >= bufferWidth) {
- /* totally out of bounds */
- n = 0;
- }
- else {
- /* left clip */
- if (x < 0) {
- skipPixels = -x;
- x = 0;
- n -= skipPixels;
- }
- /* right clip */
- if (x + n > bufferWidth) {
- GLint dx = x + n - bufferWidth;
- n -= dx;
- }
- }
-
- *count = n;
-
- return skipPixels;
-}
-#endif
-
-
-/**
- * Return a span of stencil values from the stencil buffer.
- * Used for glRead/CopyPixels
- * Input: n - how many pixels
- * x,y - location of first pixel
- * Output: stencil - the array of stencil values
- */
-void
-_swrast_read_stencil_span(GLcontext *ctx, struct gl_renderbuffer *rb,
- GLint n, GLint x, GLint y, GLstencil stencil[])
-{
- if (y < 0 || y >= (GLint) rb->Height ||
- x + n <= 0 || x >= (GLint) rb->Width) {
- /* span is completely outside framebuffer */
- return; /* undefined values OK */
- }
-
- if (x < 0) {
- GLint dx = -x;
- x = 0;
- n -= dx;
- stencil += dx;
- }
- if (x + n > (GLint) rb->Width) {
- GLint dx = x + n - rb->Width;
- n -= dx;
- }
- if (n <= 0) {
- return;
- }
-
- rb->GetRow(ctx, rb, n, x, y, stencil);
-}
-
-
-
-/**
- * Write a span of stencil values to the stencil buffer. This function
- * applies the stencil write mask when needed.
- * Used for glDraw/CopyPixels
- * Input: n - how many pixels
- * x, y - location of first pixel
- * stencil - the array of stencil values
- */
-void
-_swrast_write_stencil_span(GLcontext *ctx, GLint n, GLint x, GLint y,
- const GLstencil stencil[] )
-{
- struct gl_framebuffer *fb = ctx->DrawBuffer;
- struct gl_renderbuffer *rb = fb->_StencilBuffer;
- const GLuint stencilMax = (1 << fb->Visual.stencilBits) - 1;
- const GLuint stencilMask = ctx->Stencil.WriteMask[0];
-
- if (y < 0 || y >= (GLint) rb->Height ||
- x + n <= 0 || x >= (GLint) rb->Width) {
- /* span is completely outside framebuffer */
- return; /* undefined values OK */
- }
- if (x < 0) {
- GLint dx = -x;
- x = 0;
- n -= dx;
- stencil += dx;
- }
- if (x + n > (GLint) rb->Width) {
- GLint dx = x + n - rb->Width;
- n -= dx;
- }
- if (n <= 0) {
- return;
- }
-
- if ((stencilMask & stencilMax) != stencilMax) {
- /* need to apply writemask */
- GLstencil destVals[MAX_WIDTH], newVals[MAX_WIDTH];
- GLint i;
- rb->GetRow(ctx, rb, n, x, y, destVals);
- for (i = 0; i < n; i++) {
- newVals[i]
- = (stencil[i] & stencilMask) | (destVals[i] & ~stencilMask);
- }
- rb->PutRow(ctx, rb, n, x, y, newVals, NULL);
- }
- else {
- rb->PutRow(ctx, rb, n, x, y, stencil, NULL);
- }
-}
-
-
-
-/**
- * Clear the stencil buffer.
- */
-void
-_swrast_clear_stencil_buffer( GLcontext *ctx, struct gl_renderbuffer *rb )
-{
- const GLubyte stencilBits = ctx->DrawBuffer->Visual.stencilBits;
- const GLuint mask = ctx->Stencil.WriteMask[0];
- const GLuint invMask = ~mask;
- const GLuint clearVal = (ctx->Stencil.Clear & mask);
- const GLuint stencilMax = (1 << stencilBits) - 1;
- GLint x, y, width, height;
-
- if (!rb || mask == 0)
- return;
-
- ASSERT(rb->DataType == GL_UNSIGNED_BYTE ||
- rb->DataType == GL_UNSIGNED_SHORT);
-
- ASSERT(rb->_BaseFormat == GL_STENCIL_INDEX);
-
- /* compute region to clear */
- x = ctx->DrawBuffer->_Xmin;
- y = ctx->DrawBuffer->_Ymin;
- width = ctx->DrawBuffer->_Xmax - ctx->DrawBuffer->_Xmin;
- height = ctx->DrawBuffer->_Ymax - ctx->DrawBuffer->_Ymin;
-
- if (rb->GetPointer(ctx, rb, 0, 0)) {
- /* Direct buffer access */
- if ((mask & stencilMax) != stencilMax) {
- /* need to mask the clear */
- if (rb->DataType == GL_UNSIGNED_BYTE) {
- GLint i, j;
- for (i = 0; i < height; i++) {
- GLubyte *stencil = (GLubyte*) rb->GetPointer(ctx, rb, x, y + i);
- for (j = 0; j < width; j++) {
- stencil[j] = (stencil[j] & invMask) | clearVal;
- }
- }
- }
- else {
- GLint i, j;
- for (i = 0; i < height; i++) {
- GLushort *stencil = (GLushort*) rb->GetPointer(ctx, rb, x, y + i);
- for (j = 0; j < width; j++) {
- stencil[j] = (stencil[j] & invMask) | clearVal;
- }
- }
- }
- }
- else {
- /* no bit masking */
- if (width == (GLint) rb->Width && rb->DataType == GL_UNSIGNED_BYTE) {
- /* optimized case */
- /* Note: bottom-to-top raster assumed! */
- GLubyte *stencil = (GLubyte *) rb->GetPointer(ctx, rb, x, y);
- GLuint len = width * height * sizeof(GLubyte);
- memset(stencil, clearVal, len);
- }
- else {
- /* general case */
- GLint i;
- for (i = 0; i < height; i++) {
- GLvoid *stencil = rb->GetPointer(ctx, rb, x, y + i);
- if (rb->DataType == GL_UNSIGNED_BYTE) {
- memset(stencil, clearVal, width);
- }
- else {
- _mesa_memset16((short unsigned int*) stencil, clearVal, width);
- }
- }
- }
- }
- }
- else {
- /* no direct access */
- if ((mask & stencilMax) != stencilMax) {
- /* need to mask the clear */
- if (rb->DataType == GL_UNSIGNED_BYTE) {
- GLint i, j;
- for (i = 0; i < height; i++) {
- GLubyte stencil[MAX_WIDTH];
- rb->GetRow(ctx, rb, width, x, y + i, stencil);
- for (j = 0; j < width; j++) {
- stencil[j] = (stencil[j] & invMask) | clearVal;
- }
- rb->PutRow(ctx, rb, width, x, y + i, stencil, NULL);
- }
- }
- else {
- GLint i, j;
- for (i = 0; i < height; i++) {
- GLushort stencil[MAX_WIDTH];
- rb->GetRow(ctx, rb, width, x, y + i, stencil);
- for (j = 0; j < width; j++) {
- stencil[j] = (stencil[j] & invMask) | clearVal;
- }
- rb->PutRow(ctx, rb, width, x, y + i, stencil, NULL);
- }
- }
- }
- else {
- /* no bit masking */
- const GLubyte clear8 = (GLubyte) clearVal;
- const GLushort clear16 = (GLushort) clearVal;
- const void *clear;
- GLint i;
- if (rb->DataType == GL_UNSIGNED_BYTE) {
- clear = &clear8;
- }
- else {
- clear = &clear16;
- }
- for (i = 0; i < height; i++) {
- rb->PutMonoRow(ctx, rb, width, x, y + i, clear, NULL);
- }
- }
- }
-}
+/*
+ * Mesa 3-D graphics library
+ * Version: 7.1
+ *
+ * Copyright (C) 1999-2007 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 "main/glheader.h"
+#include "main/context.h"
+#include "main/imports.h"
+
+#include "s_context.h"
+#include "s_depth.h"
+#include "s_stencil.h"
+#include "s_span.h"
+
+
+
+/* Stencil Logic:
+
+IF stencil test fails THEN
+ Apply fail-op to stencil value
+ Don't write the pixel (RGBA,Z)
+ELSE
+ IF doing depth test && depth test fails THEN
+ Apply zfail-op to stencil value
+ Write RGBA and Z to appropriate buffers
+ ELSE
+ Apply zpass-op to stencil value
+ENDIF
+
+*/
+
+
+/**
+ * Apply the given stencil operator to the array of stencil values.
+ * Don't touch stencil[i] if mask[i] is zero.
+ * Input: n - size of stencil array
+ * oper - the stencil buffer operator
+ * face - 0 or 1 for front or back face operation
+ * stencil - array of stencil values
+ * mask - array [n] of flag: 1=apply operator, 0=don't apply operator
+ * Output: stencil - modified values
+ */
+static void
+apply_stencil_op( const struct gl_context *ctx, GLenum oper, GLuint face,
+ GLuint n, GLstencil stencil[], const GLubyte mask[] )
+{
+ const GLstencil ref = ctx->Stencil.Ref[face];
+ const GLstencil wrtmask = ctx->Stencil.WriteMask[face];
+ const GLstencil invmask = (GLstencil) (~wrtmask);
+ const GLstencil stencilMax = (1 << ctx->DrawBuffer->Visual.stencilBits) - 1;
+ GLuint i;
+
+ switch (oper) {
+ case GL_KEEP:
+ /* do nothing */
+ break;
+ case GL_ZERO:
+ if (invmask==0) {
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ stencil[i] = 0;
+ }
+ }
+ }
+ else {
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ stencil[i] = (GLstencil) (stencil[i] & invmask);
+ }
+ }
+ }
+ break;
+ case GL_REPLACE:
+ if (invmask==0) {
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ stencil[i] = ref;
+ }
+ }
+ }
+ else {
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ GLstencil s = stencil[i];
+ stencil[i] = (GLstencil) ((invmask & s ) | (wrtmask & ref));
+ }
+ }
+ }
+ break;
+ case GL_INCR:
+ if (invmask==0) {
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ GLstencil s = stencil[i];
+ if (s < stencilMax) {
+ stencil[i] = (GLstencil) (s+1);
+ }
+ }
+ }
+ }
+ else {
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ /* VERIFY logic of adding 1 to a write-masked value */
+ GLstencil s = stencil[i];
+ if (s < stencilMax) {
+ stencil[i] = (GLstencil) ((invmask & s) | (wrtmask & (s+1)));
+ }
+ }
+ }
+ }
+ break;
+ case GL_DECR:
+ if (invmask==0) {
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ GLstencil s = stencil[i];
+ if (s>0) {
+ stencil[i] = (GLstencil) (s-1);
+ }
+ }
+ }
+ }
+ else {
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ /* VERIFY logic of subtracting 1 to a write-masked value */
+ GLstencil s = stencil[i];
+ if (s>0) {
+ stencil[i] = (GLstencil) ((invmask & s) | (wrtmask & (s-1)));
+ }
+ }
+ }
+ }
+ break;
+ case GL_INCR_WRAP_EXT:
+ if (invmask==0) {
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ stencil[i]++;
+ }
+ }
+ }
+ else {
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ GLstencil s = stencil[i];
+ stencil[i] = (GLstencil) ((invmask & s) | (wrtmask & (s+1)));
+ }
+ }
+ }
+ break;
+ case GL_DECR_WRAP_EXT:
+ if (invmask==0) {
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ stencil[i]--;
+ }
+ }
+ }
+ else {
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ GLstencil s = stencil[i];
+ stencil[i] = (GLstencil) ((invmask & s) | (wrtmask & (s-1)));
+ }
+ }
+ }
+ break;
+ case GL_INVERT:
+ if (invmask==0) {
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ GLstencil s = stencil[i];
+ stencil[i] = (GLstencil) ~s;
+ }
+ }
+ }
+ else {
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ GLstencil s = stencil[i];
+ stencil[i] = (GLstencil) ((invmask & s) | (wrtmask & ~s));
+ }
+ }
+ }
+ break;
+ default:
+ _mesa_problem(ctx, "Bad stencil op in apply_stencil_op");
+ }
+}
+
+
+
+
+/**
+ * Apply stencil test to an array of stencil values (before depth buffering).
+ * Input: face - 0 or 1 for front or back-face polygons
+ * n - number of pixels in the array
+ * stencil - array of [n] stencil values
+ * mask - array [n] of flag: 0=skip the pixel, 1=stencil the pixel
+ * Output: mask - pixels which fail the stencil test will have their
+ * mask flag set to 0.
+ * stencil - updated stencil values (where the test passed)
+ * Return: GL_FALSE = all pixels failed, GL_TRUE = zero or more pixels passed.
+ */
+static GLboolean
+do_stencil_test( struct gl_context *ctx, GLuint face, GLuint n, GLstencil stencil[],
+ GLubyte mask[] )
+{
+ GLubyte fail[MAX_WIDTH];
+ GLboolean allfail = GL_FALSE;
+ GLuint i;
+ const GLuint valueMask = ctx->Stencil.ValueMask[face];
+ const GLstencil r = (GLstencil) (ctx->Stencil.Ref[face] & valueMask);
+ GLstencil s;
+
+ ASSERT(n <= MAX_WIDTH);
+
+ /*
+ * Perform stencil test. The results of this operation are stored
+ * in the fail[] array:
+ * IF fail[i] is non-zero THEN
+ * the stencil fail operator is to be applied
+ * ELSE
+ * the stencil fail operator is not to be applied
+ * ENDIF
+ */
+ switch (ctx->Stencil.Function[face]) {
+ case GL_NEVER:
+ /* never pass; always fail */
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ mask[i] = 0;
+ fail[i] = 1;
+ }
+ else {
+ fail[i] = 0;
+ }
+ }
+ allfail = GL_TRUE;
+ break;
+ case GL_LESS:
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ s = (GLstencil) (stencil[i] & valueMask);
+ if (r < s) {
+ /* passed */
+ fail[i] = 0;
+ }
+ else {
+ fail[i] = 1;
+ mask[i] = 0;
+ }
+ }
+ else {
+ fail[i] = 0;
+ }
+ }
+ break;
+ case GL_LEQUAL:
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ s = (GLstencil) (stencil[i] & valueMask);
+ if (r <= s) {
+ /* pass */
+ fail[i] = 0;
+ }
+ else {
+ fail[i] = 1;
+ mask[i] = 0;
+ }
+ }
+ else {
+ fail[i] = 0;
+ }
+ }
+ break;
+ case GL_GREATER:
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ s = (GLstencil) (stencil[i] & valueMask);
+ if (r > s) {
+ /* passed */
+ fail[i] = 0;
+ }
+ else {
+ fail[i] = 1;
+ mask[i] = 0;
+ }
+ }
+ else {
+ fail[i] = 0;
+ }
+ }
+ break;
+ case GL_GEQUAL:
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ s = (GLstencil) (stencil[i] & valueMask);
+ if (r >= s) {
+ /* passed */
+ fail[i] = 0;
+ }
+ else {
+ fail[i] = 1;
+ mask[i] = 0;
+ }
+ }
+ else {
+ fail[i] = 0;
+ }
+ }
+ break;
+ case GL_EQUAL:
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ s = (GLstencil) (stencil[i] & valueMask);
+ if (r == s) {
+ /* passed */
+ fail[i] = 0;
+ }
+ else {
+ fail[i] = 1;
+ mask[i] = 0;
+ }
+ }
+ else {
+ fail[i] = 0;
+ }
+ }
+ break;
+ case GL_NOTEQUAL:
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ s = (GLstencil) (stencil[i] & valueMask);
+ if (r != s) {
+ /* passed */
+ fail[i] = 0;
+ }
+ else {
+ fail[i] = 1;
+ mask[i] = 0;
+ }
+ }
+ else {
+ fail[i] = 0;
+ }
+ }
+ break;
+ case GL_ALWAYS:
+ /* always pass */
+ for (i=0;i<n;i++) {
+ fail[i] = 0;
+ }
+ break;
+ default:
+ _mesa_problem(ctx, "Bad stencil func in gl_stencil_span");
+ return 0;
+ }
+
+ if (ctx->Stencil.FailFunc[face] != GL_KEEP) {
+ apply_stencil_op( ctx, ctx->Stencil.FailFunc[face], face, n, stencil, fail );
+ }
+
+ return !allfail;
+}
+
+
+/**
+ * Compute the zpass/zfail masks by comparing the pre- and post-depth test
+ * masks.
+ */
+static INLINE void
+compute_pass_fail_masks(GLuint n, const GLubyte origMask[],
+ const GLubyte newMask[],
+ GLubyte passMask[], GLubyte failMask[])
+{
+ GLuint i;
+ for (i = 0; i < n; i++) {
+ ASSERT(newMask[i] == 0 || newMask[i] == 1);
+ passMask[i] = origMask[i] & newMask[i];
+ failMask[i] = origMask[i] & (newMask[i] ^ 1);
+ }
+}
+
+
+/**
+ * Apply stencil and depth testing to the span of pixels.
+ * Both software and hardware stencil buffers are acceptable.
+ * Input: n - number of pixels in the span
+ * x, y - location of leftmost pixel in span
+ * z - array [n] of z values
+ * mask - array [n] of flags (1=test this pixel, 0=skip the pixel)
+ * Output: mask - array [n] of flags (1=stencil and depth test passed)
+ * Return: GL_FALSE - all fragments failed the testing
+ * GL_TRUE - one or more fragments passed the testing
+ *
+ */
+static GLboolean
+stencil_and_ztest_span(struct gl_context *ctx, SWspan *span, GLuint face)
+{
+ struct gl_framebuffer *fb = ctx->DrawBuffer;
+ struct gl_renderbuffer *rb = fb->_StencilBuffer;
+ GLstencil stencilRow[MAX_WIDTH];
+ GLstencil *stencil;
+ const GLuint n = span->end;
+ const GLint x = span->x;
+ const GLint y = span->y;
+ GLubyte *mask = span->array->mask;
+
+ ASSERT((span->arrayMask & SPAN_XY) == 0);
+ ASSERT(ctx->Stencil.Enabled);
+ ASSERT(n <= MAX_WIDTH);
+#ifdef DEBUG
+ if (ctx->Depth.Test) {
+ ASSERT(span->arrayMask & SPAN_Z);
+ }
+#endif
+
+ stencil = (GLstencil *) rb->GetPointer(ctx, rb, x, y);
+ if (!stencil) {
+ rb->GetRow(ctx, rb, n, x, y, stencilRow);
+ stencil = stencilRow;
+ }
+
+ /*
+ * Apply the stencil test to the fragments.
+ * failMask[i] is 1 if the stencil test failed.
+ */
+ if (do_stencil_test( ctx, face, n, stencil, mask ) == GL_FALSE) {
+ /* all fragments failed the stencil test, we're done. */
+ span->writeAll = GL_FALSE;
+ if (!rb->GetPointer(ctx, rb, 0, 0)) {
+ /* put updated stencil values into buffer */
+ rb->PutRow(ctx, rb, n, x, y, stencil, NULL);
+ }
+ return GL_FALSE;
+ }
+
+ /*
+ * Some fragments passed the stencil test, apply depth test to them
+ * and apply Zpass and Zfail stencil ops.
+ */
+ if (ctx->Depth.Test == GL_FALSE) {
+ /*
+ * No depth buffer, just apply zpass stencil function to active pixels.
+ */
+ apply_stencil_op( ctx, ctx->Stencil.ZPassFunc[face], face, n, stencil, mask );
+ }
+ else {
+ /*
+ * Perform depth buffering, then apply zpass or zfail stencil function.
+ */
+ GLubyte passMask[MAX_WIDTH], failMask[MAX_WIDTH], origMask[MAX_WIDTH];
+
+ /* save the current mask bits */
+ memcpy(origMask, mask, n * sizeof(GLubyte));
+
+ /* apply the depth test */
+ _swrast_depth_test_span(ctx, span);
+
+ compute_pass_fail_masks(n, origMask, mask, passMask, failMask);
+
+ /* apply the pass and fail operations */
+ if (ctx->Stencil.ZFailFunc[face] != GL_KEEP) {
+ apply_stencil_op( ctx, ctx->Stencil.ZFailFunc[face], face,
+ n, stencil, failMask );
+ }
+ if (ctx->Stencil.ZPassFunc[face] != GL_KEEP) {
+ apply_stencil_op( ctx, ctx->Stencil.ZPassFunc[face], face,
+ n, stencil, passMask );
+ }
+ }
+
+ /*
+ * Write updated stencil values back into hardware stencil buffer.
+ */
+ if (!rb->GetPointer(ctx, rb, 0, 0)) {
+ rb->PutRow(ctx, rb, n, x, y, stencil, NULL);
+ }
+
+ span->writeAll = GL_FALSE;
+
+ return GL_TRUE; /* one or more fragments passed both tests */
+}
+
+
+
+/*
+ * Return the address of a stencil buffer value given the window coords:
+ */
+#define STENCIL_ADDRESS(X, Y) (stencilStart + (Y) * stride + (X))
+
+
+
+/**
+ * Apply the given stencil operator for each pixel in the array whose
+ * mask flag is set.
+ * \note This is for software stencil buffers only.
+ * Input: n - number of pixels in the span
+ * x, y - array of [n] pixels
+ * operator - the stencil buffer operator
+ * mask - array [n] of flag: 1=apply operator, 0=don't apply operator
+ */
+static void
+apply_stencil_op_to_pixels( struct gl_context *ctx,
+ GLuint n, const GLint x[], const GLint y[],
+ GLenum oper, GLuint face, const GLubyte mask[] )
+{
+ struct gl_framebuffer *fb = ctx->DrawBuffer;
+ struct gl_renderbuffer *rb = fb->_StencilBuffer;
+ const GLstencil stencilMax = (1 << fb->Visual.stencilBits) - 1;
+ const GLstencil ref = ctx->Stencil.Ref[face];
+ const GLstencil wrtmask = ctx->Stencil.WriteMask[face];
+ const GLstencil invmask = (GLstencil) (~wrtmask);
+ GLuint i;
+ GLstencil *stencilStart = (GLubyte *) rb->Data;
+ const GLuint stride = rb->Width;
+
+ ASSERT(rb->GetPointer(ctx, rb, 0, 0));
+ ASSERT(sizeof(GLstencil) == 1);
+
+ switch (oper) {
+ case GL_KEEP:
+ /* do nothing */
+ break;
+ case GL_ZERO:
+ if (invmask==0) {
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] );
+ *sptr = 0;
+ }
+ }
+ }
+ else {
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] );
+ *sptr = (GLstencil) (invmask & *sptr);
+ }
+ }
+ }
+ break;
+ case GL_REPLACE:
+ if (invmask==0) {
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] );
+ *sptr = ref;
+ }
+ }
+ }
+ else {
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] );
+ *sptr = (GLstencil) ((invmask & *sptr ) | (wrtmask & ref));
+ }
+ }
+ }
+ break;
+ case GL_INCR:
+ if (invmask==0) {
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] );
+ if (*sptr < stencilMax) {
+ *sptr = (GLstencil) (*sptr + 1);
+ }
+ }
+ }
+ }
+ else {
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] );
+ if (*sptr < stencilMax) {
+ *sptr = (GLstencil) ((invmask & *sptr) | (wrtmask & (*sptr+1)));
+ }
+ }
+ }
+ }
+ break;
+ case GL_DECR:
+ if (invmask==0) {
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] );
+ if (*sptr>0) {
+ *sptr = (GLstencil) (*sptr - 1);
+ }
+ }
+ }
+ }
+ else {
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] );
+ if (*sptr>0) {
+ *sptr = (GLstencil) ((invmask & *sptr) | (wrtmask & (*sptr-1)));
+ }
+ }
+ }
+ }
+ break;
+ case GL_INCR_WRAP_EXT:
+ if (invmask==0) {
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] );
+ *sptr = (GLstencil) (*sptr + 1);
+ }
+ }
+ }
+ else {
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] );
+ *sptr = (GLstencil) ((invmask & *sptr) | (wrtmask & (*sptr+1)));
+ }
+ }
+ }
+ break;
+ case GL_DECR_WRAP_EXT:
+ if (invmask==0) {
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] );
+ *sptr = (GLstencil) (*sptr - 1);
+ }
+ }
+ }
+ else {
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] );
+ *sptr = (GLstencil) ((invmask & *sptr) | (wrtmask & (*sptr-1)));
+ }
+ }
+ }
+ break;
+ case GL_INVERT:
+ if (invmask==0) {
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] );
+ *sptr = (GLstencil) (~*sptr);
+ }
+ }
+ }
+ else {
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ GLstencil *sptr = STENCIL_ADDRESS( x[i], y[i] );
+ *sptr = (GLstencil) ((invmask & *sptr) | (wrtmask & ~*sptr));
+ }
+ }
+ }
+ break;
+ default:
+ _mesa_problem(ctx, "Bad stencilop in apply_stencil_op_to_pixels");
+ }
+}
+
+
+
+/**
+ * Apply stencil test to an array of pixels before depth buffering.
+ *
+ * \note Used for software stencil buffer only.
+ * Input: n - number of pixels in the span
+ * x, y - array of [n] pixels to stencil
+ * mask - array [n] of flag: 0=skip the pixel, 1=stencil the pixel
+ * Output: mask - pixels which fail the stencil test will have their
+ * mask flag set to 0.
+ * \return GL_FALSE = all pixels failed, GL_TRUE = zero or more pixels passed.
+ */
+static GLboolean
+stencil_test_pixels( struct gl_context *ctx, GLuint face, GLuint n,
+ const GLint x[], const GLint y[], GLubyte mask[] )
+{
+ const struct gl_framebuffer *fb = ctx->DrawBuffer;
+ struct gl_renderbuffer *rb = fb->_StencilBuffer;
+ GLubyte fail[MAX_WIDTH];
+ GLstencil r, s;
+ GLuint i;
+ GLboolean allfail = GL_FALSE;
+ const GLuint valueMask = ctx->Stencil.ValueMask[face];
+ const GLstencil *stencilStart = (GLstencil *) rb->Data;
+ const GLuint stride = rb->Width;
+
+ ASSERT(rb->GetPointer(ctx, rb, 0, 0));
+ ASSERT(sizeof(GLstencil) == 1);
+
+ /*
+ * Perform stencil test. The results of this operation are stored
+ * in the fail[] array:
+ * IF fail[i] is non-zero THEN
+ * the stencil fail operator is to be applied
+ * ELSE
+ * the stencil fail operator is not to be applied
+ * ENDIF
+ */
+
+ switch (ctx->Stencil.Function[face]) {
+ case GL_NEVER:
+ /* always fail */
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ mask[i] = 0;
+ fail[i] = 1;
+ }
+ else {
+ fail[i] = 0;
+ }
+ }
+ allfail = GL_TRUE;
+ break;
+ case GL_LESS:
+ r = (GLstencil) (ctx->Stencil.Ref[face] & valueMask);
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ const GLstencil *sptr = STENCIL_ADDRESS(x[i],y[i]);
+ s = (GLstencil) (*sptr & valueMask);
+ if (r < s) {
+ /* passed */
+ fail[i] = 0;
+ }
+ else {
+ fail[i] = 1;
+ mask[i] = 0;
+ }
+ }
+ else {
+ fail[i] = 0;
+ }
+ }
+ break;
+ case GL_LEQUAL:
+ r = (GLstencil) (ctx->Stencil.Ref[face] & valueMask);
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ const GLstencil *sptr = STENCIL_ADDRESS(x[i],y[i]);
+ s = (GLstencil) (*sptr & valueMask);
+ if (r <= s) {
+ /* pass */
+ fail[i] = 0;
+ }
+ else {
+ fail[i] = 1;
+ mask[i] = 0;
+ }
+ }
+ else {
+ fail[i] = 0;
+ }
+ }
+ break;
+ case GL_GREATER:
+ r = (GLstencil) (ctx->Stencil.Ref[face] & valueMask);
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ const GLstencil *sptr = STENCIL_ADDRESS(x[i],y[i]);
+ s = (GLstencil) (*sptr & valueMask);
+ if (r > s) {
+ /* passed */
+ fail[i] = 0;
+ }
+ else {
+ fail[i] = 1;
+ mask[i] = 0;
+ }
+ }
+ else {
+ fail[i] = 0;
+ }
+ }
+ break;
+ case GL_GEQUAL:
+ r = (GLstencil) (ctx->Stencil.Ref[face] & valueMask);
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ const GLstencil *sptr = STENCIL_ADDRESS(x[i],y[i]);
+ s = (GLstencil) (*sptr & valueMask);
+ if (r >= s) {
+ /* passed */
+ fail[i] = 0;
+ }
+ else {
+ fail[i] = 1;
+ mask[i] = 0;
+ }
+ }
+ else {
+ fail[i] = 0;
+ }
+ }
+ break;
+ case GL_EQUAL:
+ r = (GLstencil) (ctx->Stencil.Ref[face] & valueMask);
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ const GLstencil *sptr = STENCIL_ADDRESS(x[i],y[i]);
+ s = (GLstencil) (*sptr & valueMask);
+ if (r == s) {
+ /* passed */
+ fail[i] = 0;
+ }
+ else {
+ fail[i] = 1;
+ mask[i] = 0;
+ }
+ }
+ else {
+ fail[i] = 0;
+ }
+ }
+ break;
+ case GL_NOTEQUAL:
+ r = (GLstencil) (ctx->Stencil.Ref[face] & valueMask);
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ const GLstencil *sptr = STENCIL_ADDRESS(x[i],y[i]);
+ s = (GLstencil) (*sptr & valueMask);
+ if (r != s) {
+ /* passed */
+ fail[i] = 0;
+ }
+ else {
+ fail[i] = 1;
+ mask[i] = 0;
+ }
+ }
+ else {
+ fail[i] = 0;
+ }
+ }
+ break;
+ case GL_ALWAYS:
+ /* always pass */
+ for (i=0;i<n;i++) {
+ fail[i] = 0;
+ }
+ break;
+ default:
+ _mesa_problem(ctx, "Bad stencil func in gl_stencil_pixels");
+ return 0;
+ }
+
+ if (ctx->Stencil.FailFunc[face] != GL_KEEP) {
+ apply_stencil_op_to_pixels( ctx, n, x, y, ctx->Stencil.FailFunc[face],
+ face, fail );
+ }
+
+ return !allfail;
+}
+
+
+
+
+/**
+ * Apply stencil and depth testing to an array of pixels.
+ * This is used both for software and hardware stencil buffers.
+ *
+ * The comments in this function are a bit sparse but the code is
+ * almost identical to stencil_and_ztest_span(), which is well
+ * commented.
+ *
+ * Input: n - number of pixels in the array
+ * x, y - array of [n] pixel positions
+ * z - array [n] of z values
+ * mask - array [n] of flags (1=test this pixel, 0=skip the pixel)
+ * Output: mask - array [n] of flags (1=stencil and depth test passed)
+ * Return: GL_FALSE - all fragments failed the testing
+ * GL_TRUE - one or more fragments passed the testing
+ */
+static GLboolean
+stencil_and_ztest_pixels( struct gl_context *ctx, SWspan *span, GLuint face )
+{
+ GLubyte passMask[MAX_WIDTH], failMask[MAX_WIDTH], origMask[MAX_WIDTH];
+ struct gl_framebuffer *fb = ctx->DrawBuffer;
+ struct gl_renderbuffer *rb = fb->_StencilBuffer;
+ const GLuint n = span->end;
+ const GLint *x = span->array->x;
+ const GLint *y = span->array->y;
+ GLubyte *mask = span->array->mask;
+
+ ASSERT(span->arrayMask & SPAN_XY);
+ ASSERT(ctx->Stencil.Enabled);
+ ASSERT(n <= MAX_WIDTH);
+
+ if (!rb->GetPointer(ctx, rb, 0, 0)) {
+ /* No direct access */
+ GLstencil stencil[MAX_WIDTH];
+
+ ASSERT(rb->DataType == GL_UNSIGNED_BYTE);
+ _swrast_get_values(ctx, rb, n, x, y, stencil, sizeof(GLubyte));
+
+ memcpy(origMask, mask, n * sizeof(GLubyte));
+
+ (void) do_stencil_test(ctx, face, n, stencil, mask);
+
+ if (ctx->Depth.Test == GL_FALSE) {
+ apply_stencil_op(ctx, ctx->Stencil.ZPassFunc[face], face,
+ n, stencil, mask);
+ }
+ else {
+ GLubyte tmpMask[MAX_WIDTH];
+ memcpy(tmpMask, mask, n * sizeof(GLubyte));
+
+ _swrast_depth_test_span(ctx, span);
+
+ compute_pass_fail_masks(n, tmpMask, mask, passMask, failMask);
+
+ if (ctx->Stencil.ZFailFunc[face] != GL_KEEP) {
+ apply_stencil_op(ctx, ctx->Stencil.ZFailFunc[face], face,
+ n, stencil, failMask);
+ }
+ if (ctx->Stencil.ZPassFunc[face] != GL_KEEP) {
+ apply_stencil_op(ctx, ctx->Stencil.ZPassFunc[face], face,
+ n, stencil, passMask);
+ }
+ }
+
+ /* Write updated stencil values into hardware stencil buffer */
+ rb->PutValues(ctx, rb, n, x, y, stencil, origMask);
+
+ return GL_TRUE;
+ }
+ else {
+ /* Direct access to stencil buffer */
+
+ if (stencil_test_pixels(ctx, face, n, x, y, mask) == GL_FALSE) {
+ /* all fragments failed the stencil test, we're done. */
+ return GL_FALSE;
+ }
+
+ if (ctx->Depth.Test==GL_FALSE) {
+ apply_stencil_op_to_pixels(ctx, n, x, y,
+ ctx->Stencil.ZPassFunc[face], face, mask);
+ }
+ else {
+ memcpy(origMask, mask, n * sizeof(GLubyte));
+
+ _swrast_depth_test_span(ctx, span);
+
+ compute_pass_fail_masks(n, origMask, mask, passMask, failMask);
+
+ if (ctx->Stencil.ZFailFunc[face] != GL_KEEP) {
+ apply_stencil_op_to_pixels(ctx, n, x, y,
+ ctx->Stencil.ZFailFunc[face],
+ face, failMask);
+ }
+ if (ctx->Stencil.ZPassFunc[face] != GL_KEEP) {
+ apply_stencil_op_to_pixels(ctx, n, x, y,
+ ctx->Stencil.ZPassFunc[face],
+ face, passMask);
+ }
+ }
+
+ return GL_TRUE; /* one or more fragments passed both tests */
+ }
+}
+
+
+/**
+ * /return GL_TRUE = one or more fragments passed,
+ * GL_FALSE = all fragments failed.
+ */
+GLboolean
+_swrast_stencil_and_ztest_span(struct gl_context *ctx, SWspan *span)
+{
+ const GLuint face = (span->facing == 0) ? 0 : ctx->Stencil._BackFace;
+
+ if (span->arrayMask & SPAN_XY)
+ return stencil_and_ztest_pixels(ctx, span, face);
+ else
+ return stencil_and_ztest_span(ctx, span, face);
+}
+
+
+#if 0
+GLuint
+clip_span(GLuint bufferWidth, GLuint bufferHeight,
+ GLint x, GLint y, GLuint *count)
+{
+ GLuint n = *count;
+ GLuint skipPixels = 0;
+
+ if (y < 0 || y >= bufferHeight || x + n <= 0 || x >= bufferWidth) {
+ /* totally out of bounds */
+ n = 0;
+ }
+ else {
+ /* left clip */
+ if (x < 0) {
+ skipPixels = -x;
+ x = 0;
+ n -= skipPixels;
+ }
+ /* right clip */
+ if (x + n > bufferWidth) {
+ GLint dx = x + n - bufferWidth;
+ n -= dx;
+ }
+ }
+
+ *count = n;
+
+ return skipPixels;
+}
+#endif
+
+
+/**
+ * Return a span of stencil values from the stencil buffer.
+ * Used for glRead/CopyPixels
+ * Input: n - how many pixels
+ * x,y - location of first pixel
+ * Output: stencil - the array of stencil values
+ */
+void
+_swrast_read_stencil_span(struct gl_context *ctx, struct gl_renderbuffer *rb,
+ GLint n, GLint x, GLint y, GLstencil stencil[])
+{
+ if (y < 0 || y >= (GLint) rb->Height ||
+ x + n <= 0 || x >= (GLint) rb->Width) {
+ /* span is completely outside framebuffer */
+ return; /* undefined values OK */
+ }
+
+ if (x < 0) {
+ GLint dx = -x;
+ x = 0;
+ n -= dx;
+ stencil += dx;
+ }
+ if (x + n > (GLint) rb->Width) {
+ GLint dx = x + n - rb->Width;
+ n -= dx;
+ }
+ if (n <= 0) {
+ return;
+ }
+
+ rb->GetRow(ctx, rb, n, x, y, stencil);
+}
+
+
+
+/**
+ * Write a span of stencil values to the stencil buffer. This function
+ * applies the stencil write mask when needed.
+ * Used for glDraw/CopyPixels
+ * Input: n - how many pixels
+ * x, y - location of first pixel
+ * stencil - the array of stencil values
+ */
+void
+_swrast_write_stencil_span(struct gl_context *ctx, GLint n, GLint x, GLint y,
+ const GLstencil stencil[] )
+{
+ struct gl_framebuffer *fb = ctx->DrawBuffer;
+ struct gl_renderbuffer *rb = fb->_StencilBuffer;
+ const GLuint stencilMax = (1 << fb->Visual.stencilBits) - 1;
+ const GLuint stencilMask = ctx->Stencil.WriteMask[0];
+
+ if (y < 0 || y >= (GLint) rb->Height ||
+ x + n <= 0 || x >= (GLint) rb->Width) {
+ /* span is completely outside framebuffer */
+ return; /* undefined values OK */
+ }
+ if (x < 0) {
+ GLint dx = -x;
+ x = 0;
+ n -= dx;
+ stencil += dx;
+ }
+ if (x + n > (GLint) rb->Width) {
+ GLint dx = x + n - rb->Width;
+ n -= dx;
+ }
+ if (n <= 0) {
+ return;
+ }
+
+ if ((stencilMask & stencilMax) != stencilMax) {
+ /* need to apply writemask */
+ GLstencil destVals[MAX_WIDTH], newVals[MAX_WIDTH];
+ GLint i;
+ rb->GetRow(ctx, rb, n, x, y, destVals);
+ for (i = 0; i < n; i++) {
+ newVals[i]
+ = (stencil[i] & stencilMask) | (destVals[i] & ~stencilMask);
+ }
+ rb->PutRow(ctx, rb, n, x, y, newVals, NULL);
+ }
+ else {
+ rb->PutRow(ctx, rb, n, x, y, stencil, NULL);
+ }
+}
+
+
+
+/**
+ * Clear the stencil buffer.
+ */
+void
+_swrast_clear_stencil_buffer( struct gl_context *ctx, struct gl_renderbuffer *rb )
+{
+ const GLubyte stencilBits = ctx->DrawBuffer->Visual.stencilBits;
+ const GLuint mask = ctx->Stencil.WriteMask[0];
+ const GLuint invMask = ~mask;
+ const GLuint clearVal = (ctx->Stencil.Clear & mask);
+ const GLuint stencilMax = (1 << stencilBits) - 1;
+ GLint x, y, width, height;
+
+ if (!rb || mask == 0)
+ return;
+
+ ASSERT(rb->DataType == GL_UNSIGNED_BYTE ||
+ rb->DataType == GL_UNSIGNED_SHORT);
+
+ ASSERT(rb->_BaseFormat == GL_STENCIL_INDEX);
+
+ /* compute region to clear */
+ x = ctx->DrawBuffer->_Xmin;
+ y = ctx->DrawBuffer->_Ymin;
+ width = ctx->DrawBuffer->_Xmax - ctx->DrawBuffer->_Xmin;
+ height = ctx->DrawBuffer->_Ymax - ctx->DrawBuffer->_Ymin;
+
+ if (rb->GetPointer(ctx, rb, 0, 0)) {
+ /* Direct buffer access */
+ if ((mask & stencilMax) != stencilMax) {
+ /* need to mask the clear */
+ if (rb->DataType == GL_UNSIGNED_BYTE) {
+ GLint i, j;
+ for (i = 0; i < height; i++) {
+ GLubyte *stencil = (GLubyte*) rb->GetPointer(ctx, rb, x, y + i);
+ for (j = 0; j < width; j++) {
+ stencil[j] = (stencil[j] & invMask) | clearVal;
+ }
+ }
+ }
+ else {
+ GLint i, j;
+ for (i = 0; i < height; i++) {
+ GLushort *stencil = (GLushort*) rb->GetPointer(ctx, rb, x, y + i);
+ for (j = 0; j < width; j++) {
+ stencil[j] = (stencil[j] & invMask) | clearVal;
+ }
+ }
+ }
+ }
+ else {
+ /* no bit masking */
+ if (width == (GLint) rb->Width && rb->DataType == GL_UNSIGNED_BYTE) {
+ /* optimized case */
+ /* Note: bottom-to-top raster assumed! */
+ GLubyte *stencil = (GLubyte *) rb->GetPointer(ctx, rb, x, y);
+ GLuint len = width * height * sizeof(GLubyte);
+ memset(stencil, clearVal, len);
+ }
+ else {
+ /* general case */
+ GLint i;
+ for (i = 0; i < height; i++) {
+ GLvoid *stencil = rb->GetPointer(ctx, rb, x, y + i);
+ if (rb->DataType == GL_UNSIGNED_BYTE) {
+ memset(stencil, clearVal, width);
+ }
+ else {
+ _mesa_memset16((short unsigned int*) stencil, clearVal, width);
+ }
+ }
+ }
+ }
+ }
+ else {
+ /* no direct access */
+ if ((mask & stencilMax) != stencilMax) {
+ /* need to mask the clear */
+ if (rb->DataType == GL_UNSIGNED_BYTE) {
+ GLint i, j;
+ for (i = 0; i < height; i++) {
+ GLubyte stencil[MAX_WIDTH];
+ rb->GetRow(ctx, rb, width, x, y + i, stencil);
+ for (j = 0; j < width; j++) {
+ stencil[j] = (stencil[j] & invMask) | clearVal;
+ }
+ rb->PutRow(ctx, rb, width, x, y + i, stencil, NULL);
+ }
+ }
+ else {
+ GLint i, j;
+ for (i = 0; i < height; i++) {
+ GLushort stencil[MAX_WIDTH];
+ rb->GetRow(ctx, rb, width, x, y + i, stencil);
+ for (j = 0; j < width; j++) {
+ stencil[j] = (stencil[j] & invMask) | clearVal;
+ }
+ rb->PutRow(ctx, rb, width, x, y + i, stencil, NULL);
+ }
+ }
+ }
+ else {
+ /* no bit masking */
+ const GLubyte clear8 = (GLubyte) clearVal;
+ const GLushort clear16 = (GLushort) clearVal;
+ const void *clear;
+ GLint i;
+ if (rb->DataType == GL_UNSIGNED_BYTE) {
+ clear = &clear8;
+ }
+ else {
+ clear = &clear16;
+ }
+ for (i = 0; i < height; i++) {
+ rb->PutMonoRow(ctx, rb, width, x, y + i, clear, NULL);
+ }
+ }
+ }
+}
generated by cgit v1.2.3 (git 2.25.1) at 2024-07-04 11:05:16 +0000