-/* $Id: depth.c,v 1.10 1999/11/24 18:48:31 brianp Exp $ */
+/* $Id: depth.c,v 1.16 2000/04/04 00:54:23 brianp Exp $ */
/*
* Mesa 3-D graphics library
* Version: 3.3
*
- * Copyright (C) 1999 Brian Paul All Rights Reserved.
+ * 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"),
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
+
#ifdef PC_HEADER
#include "all.h"
#else
#include "enums.h"
#include "depth.h"
#include "mem.h"
+#include "pb.h"
#include "types.h"
#endif
/**********************************************************************/
-/***** Depth Testing Functions *****/
+/***** Misc *****/
/**********************************************************************/
-
/*
- * Depth test horizontal spans of fragments. These functions are called
- * via ctx->Driver.depth_test_span only.
- *
- * Input: n - number of pixels in the span
- * x, y - location of leftmost pixel in span in window coords
- * z - array [n] of integer depth values
- * In/Out: mask - array [n] of flags (1=draw pixel, 0=don't draw)
- * Return: number of pixels which passed depth test
+ * Return address of depth buffer value for given window coord.
*/
+GLvoid *
+_mesa_zbuffer_address(GLcontext *ctx, GLint x, GLint y)
+{
+ if (ctx->Visual->DepthBits <= 16)
+ return (GLushort *) ctx->DrawBuffer->DepthBuffer + ctx->DrawBuffer->Width * y + x;
+ else
+ return (GLuint *) ctx->DrawBuffer->DepthBuffer + ctx->DrawBuffer->Width * y + x;
+}
+
+
+#define Z_ADDRESS16( CTX, X, Y ) \
+ ( ((GLushort *) (CTX)->DrawBuffer->DepthBuffer) \
+ + (CTX)->DrawBuffer->Width * (Y) + (X) )
+
+#define Z_ADDRESS32( CTX, X, Y ) \
+ ( ((GLuint *) (CTX)->DrawBuffer->DepthBuffer) \
+ + (CTX)->DrawBuffer->Width * (Y) + (X) )
+
+
+
+/**********************************************************************/
+/***** Depth Testing Functions *****/
+/**********************************************************************/
/*
- * glDepthFunc( any ) and glDepthMask( GL_TRUE or GL_FALSE ).
+ * Do depth test for an array of fragments. This is used both for
+ * software and hardware Z buffers.
+ * Input: zbuffer - array of z values in the zbuffer
+ * z - array of fragment z values
+ * Return: number of fragments which pass the test.
*/
-GLuint gl_depth_test_span_generic( GLcontext* ctx,
- GLuint n, GLint x, GLint y,
- const GLdepth z[],
- GLubyte mask[] )
+static GLuint
+depth_test_span16( GLcontext *ctx, GLuint n, GLint x, GLint y,
+ GLushort zbuffer[], const GLdepth z[], GLubyte mask[] )
{
- GLdepth *zptr = Z_ADDRESS( ctx, x, y );
- GLubyte *m = mask;
- GLuint i;
GLuint passed = 0;
/* switch cases ordered from most frequent to less frequent */
case GL_LESS:
if (ctx->Depth.Mask) {
/* Update Z buffer */
- for (i=0; i<n; i++,zptr++,m++) {
- if (*m) {
- if (z[i] < *zptr) {
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ if (z[i] < zbuffer[i]) {
/* pass */
- *zptr = z[i];
+ zbuffer[i] = z[i];
passed++;
}
else {
/* fail */
- *m = 0;
+ mask[i] = 0;
}
}
}
}
else {
/* Don't update Z buffer */
- for (i=0; i<n; i++,zptr++,m++) {
- if (*m) {
- if (z[i] < *zptr) {
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ if (z[i] < zbuffer[i]) {
/* pass */
passed++;
}
else {
- *m = 0;
+ mask[i] = 0;
}
}
}
case GL_LEQUAL:
if (ctx->Depth.Mask) {
/* Update Z buffer */
- for (i=0;i<n;i++,zptr++,m++) {
- if (*m) {
- if (z[i] <= *zptr) {
- *zptr = z[i];
+ GLuint i;
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ if (z[i] <= zbuffer[i]) {
+ zbuffer[i] = z[i];
passed++;
}
else {
- *m = 0;
+ mask[i] = 0;
}
}
}
}
else {
/* Don't update Z buffer */
- for (i=0;i<n;i++,zptr++,m++) {
- if (*m) {
- if (z[i] <= *zptr) {
+ GLuint i;
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ if (z[i] <= zbuffer[i]) {
/* pass */
passed++;
}
else {
- *m = 0;
+ mask[i] = 0;
}
}
}
case GL_GEQUAL:
if (ctx->Depth.Mask) {
/* Update Z buffer */
- for (i=0;i<n;i++,zptr++,m++) {
- if (*m) {
- if (z[i] >= *zptr) {
- *zptr = z[i];
+ GLuint i;
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ if (z[i] >= zbuffer[i]) {
+ zbuffer[i] = z[i];
passed++;
}
else {
- *m = 0;
+ mask[i] = 0;
}
}
}
}
else {
/* Don't update Z buffer */
- for (i=0;i<n;i++,zptr++,m++) {
- if (*m) {
- if (z[i] >= *zptr) {
+ GLuint i;
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ if (z[i] >= zbuffer[i]) {
/* pass */
passed++;
}
else {
- *m = 0;
+ mask[i] = 0;
}
}
}
case GL_GREATER:
if (ctx->Depth.Mask) {
/* Update Z buffer */
- for (i=0;i<n;i++,zptr++,m++) {
- if (*m) {
- if (z[i] > *zptr) {
- *zptr = z[i];
+ GLuint i;
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ if (z[i] > zbuffer[i]) {
+ zbuffer[i] = z[i];
passed++;
}
else {
- *m = 0;
+ mask[i] = 0;
}
}
}
}
else {
/* Don't update Z buffer */
- for (i=0;i<n;i++,zptr++,m++) {
- if (*m) {
- if (z[i] > *zptr) {
+ GLuint i;
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ if (z[i] > zbuffer[i]) {
/* pass */
passed++;
}
else {
- *m = 0;
+ mask[i] = 0;
}
}
}
case GL_NOTEQUAL:
if (ctx->Depth.Mask) {
/* Update Z buffer */
- for (i=0;i<n;i++,zptr++,m++) {
- if (*m) {
- if (z[i] != *zptr) {
- *zptr = z[i];
+ GLuint i;
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ if (z[i] != zbuffer[i]) {
+ zbuffer[i] = z[i];
passed++;
}
else {
- *m = 0;
+ mask[i] = 0;
}
}
}
}
else {
/* Don't update Z buffer */
- for (i=0;i<n;i++,zptr++,m++) {
- if (*m) {
- if (z[i] != *zptr) {
+ GLuint i;
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ if (z[i] != zbuffer[i]) {
/* pass */
passed++;
}
else {
- *m = 0;
+ mask[i] = 0;
}
}
}
case GL_EQUAL:
if (ctx->Depth.Mask) {
/* Update Z buffer */
- for (i=0;i<n;i++,zptr++,m++) {
- if (*m) {
- if (z[i] == *zptr) {
- *zptr = z[i];
+ GLuint i;
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ if (z[i] == zbuffer[i]) {
+ zbuffer[i] = z[i];
passed++;
}
else {
- *m =0;
+ mask[i] = 0;
}
}
}
}
else {
/* Don't update Z buffer */
- for (i=0;i<n;i++,zptr++,m++) {
- if (*m) {
- if (z[i] == *zptr) {
+ GLuint i;
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ if (z[i] == zbuffer[i]) {
/* pass */
passed++;
}
else {
- *m =0;
+ mask[i] = 0;
}
}
}
case GL_ALWAYS:
if (ctx->Depth.Mask) {
/* Update Z buffer */
- for (i=0;i<n;i++,zptr++,m++) {
- if (*m) {
- *zptr = z[i];
+ GLuint i;
+ for (i=0;i<n;i++) {
+ if (mask[i]) {
+ zbuffer[i] = z[i];
passed++;
}
}
}
break;
case GL_NEVER:
- for (i=0;i<n;i++) {
- mask[i] = 0;
- }
+ BZERO(mask, n * sizeof(GLubyte));
break;
default:
- gl_problem(ctx, "Bad depth func in gl_depth_test_span_generic");
- } /*switch*/
-
- return passed;
-}
-
-
-
-/*
- * glDepthFunc(GL_LESS) and glDepthMask(GL_TRUE).
- */
-GLuint gl_depth_test_span_less( GLcontext* ctx,
- GLuint n, GLint x, GLint y, const GLdepth z[],
- GLubyte mask[] )
-{
- GLdepth *zptr = Z_ADDRESS( ctx, x, y );
- GLuint i;
- GLuint passed = 0;
-
- for (i=0; i<n; i++) {
- if (mask[i]) {
- if (z[i] < zptr[i]) {
- /* pass */
- zptr[i] = z[i];
- passed++;
- }
- else {
- /* fail */
- mask[i] = 0;
- }
- }
+ gl_problem(ctx, "Bad depth func in depth_test_span16");
}
- return passed;
-}
-
-
-/*
- * glDepthFunc(GL_GREATER) and glDepthMask(GL_TRUE).
- */
-GLuint gl_depth_test_span_greater( GLcontext* ctx,
- GLuint n, GLint x, GLint y,
- const GLdepth z[],
- GLubyte mask[] )
-{
- GLdepth *zptr = Z_ADDRESS( ctx, x, y );
- GLuint i;
- GLuint passed = 0;
- for (i=0; i<n; i++) {
- if (mask[i]) {
- if (z[i] > zptr[i]) {
- /* pass */
- zptr[i] = z[i];
- passed++;
- }
- else {
- /* fail */
- mask[i] = 0;
- }
- }
- }
return passed;
}
-
-/*
- * Depth test an array of randomly positioned fragments.
- */
-
-
-#define ZADDR_SETUP GLdepth *depthbuffer = ctx->Buffer->Depth; \
- GLint width = ctx->Buffer->Width;
-
-#define ZADDR( X, Y ) (depthbuffer + (Y) * width + (X) )
-
-
-
-/*
- * glDepthFunc( any ) and glDepthMask( GL_TRUE or GL_FALSE ).
- */
-void gl_depth_test_pixels_generic( GLcontext* ctx,
- GLuint n, const GLint x[], const GLint y[],
- const GLdepth z[], GLubyte mask[] )
+static GLuint
+depth_test_span32( GLcontext *ctx, GLuint n, GLint x, GLint y,
+ GLuint zbuffer[], const GLdepth z[], GLubyte mask[] )
{
- register GLdepth *zptr;
- register GLuint i;
+ GLuint passed = 0;
/* switch cases ordered from most frequent to less frequent */
switch (ctx->Depth.Func) {
case GL_LESS:
if (ctx->Depth.Mask) {
/* Update Z buffer */
+ GLuint i;
for (i=0; i<n; i++) {
if (mask[i]) {
- zptr = Z_ADDRESS(ctx,x[i],y[i]);
- if (z[i] < *zptr) {
+ if (z[i] < zbuffer[i]) {
/* pass */
- *zptr = z[i];
+ zbuffer[i] = z[i];
+ passed++;
}
else {
/* fail */
}
else {
/* Don't update Z buffer */
+ GLuint i;
for (i=0; i<n; i++) {
if (mask[i]) {
- zptr = Z_ADDRESS(ctx,x[i],y[i]);
- if (z[i] < *zptr) {
+ if (z[i] < zbuffer[i]) {
/* pass */
+ passed++;
}
else {
- /* fail */
mask[i] = 0;
}
}
}
break;
case GL_LEQUAL:
- if (ctx->Depth.Mask) {
+ if (ctx->Depth.Mask) {
/* Update Z buffer */
- for (i=0; i<n; i++) {
+ GLuint i;
+ for (i=0;i<n;i++) {
if (mask[i]) {
- zptr = Z_ADDRESS(ctx,x[i],y[i]);
- if (z[i] <= *zptr) {
- /* pass */
- *zptr = z[i];
+ if (z[i] <= zbuffer[i]) {
+ zbuffer[i] = z[i];
+ passed++;
}
else {
- /* fail */
mask[i] = 0;
}
}
}
else {
/* Don't update Z buffer */
- for (i=0; i<n; i++) {
+ GLuint i;
+ for (i=0;i<n;i++) {
if (mask[i]) {
- zptr = Z_ADDRESS(ctx,x[i],y[i]);
- if (z[i] <= *zptr) {
+ if (z[i] <= zbuffer[i]) {
/* pass */
+ passed++;
}
else {
- /* fail */
mask[i] = 0;
}
}
}
break;
case GL_GEQUAL:
- if (ctx->Depth.Mask) {
+ if (ctx->Depth.Mask) {
/* Update Z buffer */
- for (i=0; i<n; i++) {
+ GLuint i;
+ for (i=0;i<n;i++) {
if (mask[i]) {
- zptr = Z_ADDRESS(ctx,x[i],y[i]);
- if (z[i] >= *zptr) {
- /* pass */
- *zptr = z[i];
+ if (z[i] >= zbuffer[i]) {
+ zbuffer[i] = z[i];
+ passed++;
}
else {
- /* fail */
mask[i] = 0;
}
}
}
else {
/* Don't update Z buffer */
- for (i=0; i<n; i++) {
+ GLuint i;
+ for (i=0;i<n;i++) {
if (mask[i]) {
- zptr = Z_ADDRESS(ctx,x[i],y[i]);
- if (z[i] >= *zptr) {
+ if (z[i] >= zbuffer[i]) {
/* pass */
+ passed++;
}
else {
- /* fail */
mask[i] = 0;
}
}
}
break;
case GL_GREATER:
- if (ctx->Depth.Mask) {
+ if (ctx->Depth.Mask) {
/* Update Z buffer */
- for (i=0; i<n; i++) {
+ GLuint i;
+ for (i=0;i<n;i++) {
if (mask[i]) {
- zptr = Z_ADDRESS(ctx,x[i],y[i]);
- if (z[i] > *zptr) {
- /* pass */
- *zptr = z[i];
+ if (z[i] > zbuffer[i]) {
+ zbuffer[i] = z[i];
+ passed++;
}
else {
- /* fail */
mask[i] = 0;
}
}
}
else {
/* Don't update Z buffer */
- for (i=0; i<n; i++) {
+ GLuint i;
+ for (i=0;i<n;i++) {
if (mask[i]) {
- zptr = Z_ADDRESS(ctx,x[i],y[i]);
- if (z[i] > *zptr) {
+ if (z[i] > zbuffer[i]) {
/* pass */
+ passed++;
}
else {
- /* fail */
mask[i] = 0;
}
}
}
break;
case GL_NOTEQUAL:
- if (ctx->Depth.Mask) {
+ if (ctx->Depth.Mask) {
/* Update Z buffer */
- for (i=0; i<n; i++) {
+ GLuint i;
+ for (i=0;i<n;i++) {
if (mask[i]) {
- zptr = Z_ADDRESS(ctx,x[i],y[i]);
- if (z[i] != *zptr) {
- /* pass */
- *zptr = z[i];
+ if (z[i] != zbuffer[i]) {
+ zbuffer[i] = z[i];
+ passed++;
}
else {
- /* fail */
mask[i] = 0;
}
}
}
else {
/* Don't update Z buffer */
- for (i=0; i<n; i++) {
+ GLuint i;
+ for (i=0;i<n;i++) {
if (mask[i]) {
- zptr = Z_ADDRESS(ctx,x[i],y[i]);
- if (z[i] != *zptr) {
+ if (z[i] != zbuffer[i]) {
/* pass */
+ passed++;
}
else {
- /* fail */
mask[i] = 0;
}
}
}
break;
case GL_EQUAL:
- if (ctx->Depth.Mask) {
+ if (ctx->Depth.Mask) {
/* Update Z buffer */
- for (i=0; i<n; i++) {
+ GLuint i;
+ for (i=0;i<n;i++) {
if (mask[i]) {
- zptr = Z_ADDRESS(ctx,x[i],y[i]);
- if (z[i] == *zptr) {
- /* pass */
- *zptr = z[i];
+ if (z[i] == zbuffer[i]) {
+ zbuffer[i] = z[i];
+ passed++;
}
else {
- /* fail */
mask[i] = 0;
}
}
}
else {
/* Don't update Z buffer */
- for (i=0; i<n; i++) {
+ GLuint i;
+ for (i=0;i<n;i++) {
if (mask[i]) {
- zptr = Z_ADDRESS(ctx,x[i],y[i]);
- if (z[i] == *zptr) {
+ if (z[i] == zbuffer[i]) {
/* pass */
+ passed++;
}
else {
- /* fail */
mask[i] = 0;
}
}
case GL_ALWAYS:
if (ctx->Depth.Mask) {
/* Update Z buffer */
- for (i=0; i<n; i++) {
+ GLuint i;
+ for (i=0;i<n;i++) {
if (mask[i]) {
- zptr = Z_ADDRESS(ctx,x[i],y[i]);
- *zptr = z[i];
+ zbuffer[i] = z[i];
+ passed++;
}
}
}
else {
/* Don't update Z buffer or mask */
+ passed = n;
}
break;
case GL_NEVER:
- /* depth test never passes */
- for (i=0;i<n;i++) {
- mask[i] = 0;
- }
+ BZERO(mask, n * sizeof(GLubyte));
break;
default:
- gl_problem(ctx, "Bad depth func in gl_depth_test_pixels_generic");
- } /*switch*/
-}
-
-
-
-/*
- * glDepthFunc( GL_LESS ) and glDepthMask( GL_TRUE ).
- */
-void gl_depth_test_pixels_less( GLcontext* ctx,
- GLuint n, const GLint x[], const GLint y[],
- const GLdepth z[], GLubyte mask[] )
-{
- GLdepth *zptr;
- GLuint i;
-
- for (i=0; i<n; i++) {
- if (mask[i]) {
- zptr = Z_ADDRESS(ctx,x[i],y[i]);
- if (z[i] < *zptr) {
- /* pass */
- *zptr = z[i];
- }
- else {
- /* fail */
- mask[i] = 0;
- }
- }
+ gl_problem(ctx, "Bad depth func in depth_test_span32");
}
-}
-
-/*
- * glDepthFunc( GL_GREATER ) and glDepthMask( GL_TRUE ).
- */
-void gl_depth_test_pixels_greater( GLcontext* ctx,
- GLuint n, const GLint x[], const GLint y[],
- const GLdepth z[], GLubyte mask[] )
-{
- GLdepth *zptr;
- GLuint i;
-
- for (i=0; i<n; i++) {
- if (mask[i]) {
- zptr = Z_ADDRESS(ctx,x[i],y[i]);
- if (z[i] > *zptr) {
- /* pass */
- *zptr = z[i];
- }
- else {
- /* fail */
- mask[i] = 0;
- }
- }
- }
+ return passed;
}
-
-/**********************************************************************/
-/***** Read Depth Buffer *****/
-/**********************************************************************/
-
-
/*
- * Return a span of depth values from the depth buffer as floats in [0,1].
- * This function is only called through Driver.read_depth_span_float()
- * Input: n - how many pixels
- * x,y - location of first pixel
- * Output: depth - the array of depth values
+ * Apply depth test to span of fragments. Hardware or software z buffer.
*/
-void gl_read_depth_span_float( GLcontext* ctx,
- GLuint n, GLint x, GLint y, GLfloat depth[] )
+GLuint
+_mesa_depth_test_span( GLcontext *ctx, GLuint n, GLint x, GLint y,
+ const GLdepth z[], GLubyte mask[] )
{
- GLdepth *zptr;
- GLfloat scale;
- GLuint i;
-
- scale = 1.0F / DEPTH_SCALE;
-
- if (ctx->DrawBuffer->Depth) {
- zptr = Z_ADDRESS( ctx, x, y );
- for (i=0;i<n;i++) {
- depth[i] = (GLfloat) zptr[i] * scale;
- }
+ if (ctx->Driver.ReadDepthSpan) {
+ /* hardware-based depth buffer */
+ GLdepth zbuffer[MAX_WIDTH];
+ GLuint passed;
+ (*ctx->Driver.ReadDepthSpan)(ctx, n, x, y, zbuffer);
+ passed = depth_test_span32(ctx, n, x, y, zbuffer, z, mask);
+ assert(ctx->Driver.WriteDepthSpan);
+ (*ctx->Driver.WriteDepthSpan)(ctx, n, x, y, zbuffer, mask);
+ return passed;
}
else {
- for (i=0;i<n;i++) {
- depth[i] = 0.0F;
+ /* software depth buffer */
+ if (ctx->Visual->DepthBits <= 16) {
+ GLushort *zptr = (GLushort *) Z_ADDRESS16(ctx, x, y);
+ GLuint passed = depth_test_span16(ctx, n, x, y, zptr, z, mask);
+ return passed;
}
- }
-}
-
-
-/*
- * Return a span of depth values from the depth buffer as integers in
- * [0,MAX_DEPTH].
- * This function is only called through Driver.read_depth_span_int()
- * Input: n - how many pixels
- * x,y - location of first pixel
- * Output: depth - the array of depth values
- */
-void gl_read_depth_span_int( GLcontext* ctx,
- GLuint n, GLint x, GLint y, GLdepth depth[] )
-{
- if (ctx->DrawBuffer->Depth) {
- GLdepth *zptr = Z_ADDRESS( ctx, x, y );
- MEMCPY( depth, zptr, n * sizeof(GLdepth) );
- }
- else {
- GLuint i;
- for (i=0;i<n;i++) {
- depth[i] = 0;
+ else {
+ GLuint *zptr = (GLuint *) Z_ADDRESS32(ctx, x, y);
+ GLuint passed = depth_test_span32(ctx, n, x, y, zptr, z, mask);
+ return passed;
}
}
}
-/**********************************************************************/
-/***** Allocate and Clear Depth Buffer *****/
-/**********************************************************************/
-
-
-
-/*
- * Allocate a new depth buffer. If there's already a depth buffer allocated
- * it will be free()'d. The new depth buffer will be uniniitalized.
- * This function is only called through Driver.alloc_depth_buffer.
- */
-void gl_alloc_depth_buffer( GLcontext* ctx )
-{
- /* deallocate current depth buffer if present */
- if (ctx->DrawBuffer->Depth) {
- FREE(ctx->DrawBuffer->Depth);
- ctx->DrawBuffer->Depth = NULL;
- }
-
- /* allocate new depth buffer, but don't initialize it */
- ctx->DrawBuffer->Depth = (GLdepth *) MALLOC( ctx->DrawBuffer->Width
- * ctx->DrawBuffer->Height
- * sizeof(GLdepth) );
- if (!ctx->DrawBuffer->Depth) {
- /* out of memory */
- ctx->Depth.Test = GL_FALSE;
- ctx->NewState |= NEW_RASTER_OPS;
- gl_error( ctx, GL_OUT_OF_MEMORY, "Couldn't allocate depth buffer" );
- }
-}
-
-
-
/*
- * Clear the depth buffer. If the depth buffer doesn't exist yet we'll
- * allocate it now.
- * This function is only called through Driver.clear_depth_buffer.
+ * Do depth testing for an array of fragments using software Z buffer.
*/
-void gl_clear_depth_buffer( GLcontext* ctx )
+static void
+software_depth_test_pixels16( GLcontext *ctx, GLuint n,
+ const GLint x[], const GLint y[],
+ const GLdepth z[], GLubyte mask[] )
{
- GLdepth clear_value = (GLdepth) (ctx->Depth.Clear * DEPTH_SCALE);
-
- if (ctx->Visual->DepthBits==0 || !ctx->DrawBuffer->Depth || !ctx->Depth.Mask) {
- /* no depth buffer, or writing to it is disabled */
- return;
- }
-
- /* The loops in this function have been written so the IRIX 5.3
- * C compiler can unroll them. Hopefully other compilers can too!
- */
-
- if (ctx->Scissor.Enabled) {
- /* only clear scissor region */
- GLint y;
- for (y=ctx->DrawBuffer->Ymin; y<=ctx->DrawBuffer->Ymax; y++) {
- GLdepth *d = Z_ADDRESS( ctx, ctx->DrawBuffer->Xmin, y );
- GLint n = ctx->DrawBuffer->Xmax - ctx->DrawBuffer->Xmin + 1;
- do {
- *d++ = clear_value;
- n--;
- } while (n);
- }
+ /* switch cases ordered from most frequent to less frequent */
+ switch (ctx->Depth.Func) {
+ case GL_LESS:
+ if (ctx->Depth.Mask) {
+ /* Update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ GLushort *zptr = Z_ADDRESS16(ctx,x[i],y[i]);
+ if (z[i] < *zptr) {
+ /* pass */
+ *zptr = z[i];
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ else {
+ /* Don't update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ GLushort *zptr = Z_ADDRESS16(ctx,x[i],y[i]);
+ if (z[i] < *zptr) {
+ /* pass */
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ break;
+ case GL_LEQUAL:
+ if (ctx->Depth.Mask) {
+ /* Update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ GLushort *zptr = Z_ADDRESS16(ctx,x[i],y[i]);
+ if (z[i] <= *zptr) {
+ /* pass */
+ *zptr = z[i];
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ else {
+ /* Don't update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ GLushort *zptr = Z_ADDRESS16(ctx,x[i],y[i]);
+ if (z[i] <= *zptr) {
+ /* pass */
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ break;
+ case GL_GEQUAL:
+ if (ctx->Depth.Mask) {
+ /* Update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ GLushort *zptr = Z_ADDRESS16(ctx,x[i],y[i]);
+ if (z[i] >= *zptr) {
+ /* pass */
+ *zptr = z[i];
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ else {
+ /* Don't update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ GLushort *zptr = Z_ADDRESS16(ctx,x[i],y[i]);
+ if (z[i] >= *zptr) {
+ /* pass */
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ break;
+ case GL_GREATER:
+ if (ctx->Depth.Mask) {
+ /* Update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ GLushort *zptr = Z_ADDRESS16(ctx,x[i],y[i]);
+ if (z[i] > *zptr) {
+ /* pass */
+ *zptr = z[i];
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ else {
+ /* Don't update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ GLushort *zptr = Z_ADDRESS16(ctx,x[i],y[i]);
+ if (z[i] > *zptr) {
+ /* pass */
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ break;
+ case GL_NOTEQUAL:
+ if (ctx->Depth.Mask) {
+ /* Update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ GLushort *zptr = Z_ADDRESS16(ctx,x[i],y[i]);
+ if (z[i] != *zptr) {
+ /* pass */
+ *zptr = z[i];
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ else {
+ /* Don't update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ GLushort *zptr = Z_ADDRESS16(ctx,x[i],y[i]);
+ if (z[i] != *zptr) {
+ /* pass */
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ break;
+ case GL_EQUAL:
+ if (ctx->Depth.Mask) {
+ /* Update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ GLushort *zptr = Z_ADDRESS16(ctx,x[i],y[i]);
+ if (z[i] == *zptr) {
+ /* pass */
+ *zptr = z[i];
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ else {
+ /* Don't update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ GLushort *zptr = Z_ADDRESS16(ctx,x[i],y[i]);
+ if (z[i] == *zptr) {
+ /* pass */
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ break;
+ case GL_ALWAYS:
+ if (ctx->Depth.Mask) {
+ /* Update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ GLushort *zptr = Z_ADDRESS16(ctx,x[i],y[i]);
+ *zptr = z[i];
+ }
+ }
+ }
+ else {
+ /* Don't update Z buffer or mask */
+ }
+ break;
+ case GL_NEVER:
+ /* depth test never passes */
+ BZERO(mask, n * sizeof(GLubyte));
+ break;
+ default:
+ gl_problem(ctx, "Bad depth func in software_depth_test_pixels");
+ }
+}
+
+
+
+/*
+ * Do depth testing for an array of fragments using software Z buffer.
+ */
+static void
+software_depth_test_pixels32( GLcontext *ctx, GLuint n,
+ const GLint x[], const GLint y[],
+ const GLdepth z[], GLubyte mask[] )
+{
+ /* switch cases ordered from most frequent to less frequent */
+ switch (ctx->Depth.Func) {
+ case GL_LESS:
+ if (ctx->Depth.Mask) {
+ /* Update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ GLuint *zptr = Z_ADDRESS32(ctx,x[i],y[i]);
+ if (z[i] < *zptr) {
+ /* pass */
+ *zptr = z[i];
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ else {
+ /* Don't update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ GLuint *zptr = Z_ADDRESS32(ctx,x[i],y[i]);
+ if (z[i] < *zptr) {
+ /* pass */
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ break;
+ case GL_LEQUAL:
+ if (ctx->Depth.Mask) {
+ /* Update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ GLuint *zptr = Z_ADDRESS32(ctx,x[i],y[i]);
+ if (z[i] <= *zptr) {
+ /* pass */
+ *zptr = z[i];
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ else {
+ /* Don't update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ GLuint *zptr = Z_ADDRESS32(ctx,x[i],y[i]);
+ if (z[i] <= *zptr) {
+ /* pass */
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ break;
+ case GL_GEQUAL:
+ if (ctx->Depth.Mask) {
+ /* Update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ GLuint *zptr = Z_ADDRESS32(ctx,x[i],y[i]);
+ if (z[i] >= *zptr) {
+ /* pass */
+ *zptr = z[i];
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ else {
+ /* Don't update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ GLuint *zptr = Z_ADDRESS32(ctx,x[i],y[i]);
+ if (z[i] >= *zptr) {
+ /* pass */
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ break;
+ case GL_GREATER:
+ if (ctx->Depth.Mask) {
+ /* Update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ GLuint *zptr = Z_ADDRESS32(ctx,x[i],y[i]);
+ if (z[i] > *zptr) {
+ /* pass */
+ *zptr = z[i];
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ else {
+ /* Don't update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ GLuint *zptr = Z_ADDRESS32(ctx,x[i],y[i]);
+ if (z[i] > *zptr) {
+ /* pass */
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ break;
+ case GL_NOTEQUAL:
+ if (ctx->Depth.Mask) {
+ /* Update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ GLuint *zptr = Z_ADDRESS32(ctx,x[i],y[i]);
+ if (z[i] != *zptr) {
+ /* pass */
+ *zptr = z[i];
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ else {
+ /* Don't update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ GLuint *zptr = Z_ADDRESS32(ctx,x[i],y[i]);
+ if (z[i] != *zptr) {
+ /* pass */
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ break;
+ case GL_EQUAL:
+ if (ctx->Depth.Mask) {
+ /* Update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ GLuint *zptr = Z_ADDRESS32(ctx,x[i],y[i]);
+ if (z[i] == *zptr) {
+ /* pass */
+ *zptr = z[i];
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ else {
+ /* Don't update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ GLuint *zptr = Z_ADDRESS32(ctx,x[i],y[i]);
+ if (z[i] == *zptr) {
+ /* pass */
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ break;
+ case GL_ALWAYS:
+ if (ctx->Depth.Mask) {
+ /* Update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ GLuint *zptr = Z_ADDRESS32(ctx,x[i],y[i]);
+ *zptr = z[i];
+ }
+ }
+ }
+ else {
+ /* Don't update Z buffer or mask */
+ }
+ break;
+ case GL_NEVER:
+ /* depth test never passes */
+ BZERO(mask, n * sizeof(GLubyte));
+ break;
+ default:
+ gl_problem(ctx, "Bad depth func in software_depth_test_pixels");
+ }
+}
+
+
+
+/*
+ * Do depth testing for an array of pixels using hardware Z buffer.
+ * Input/output: zbuffer - array of depth values from Z buffer
+ * Input: z - array of fragment z values.
+ */
+static void
+hardware_depth_test_pixels( GLcontext *ctx, GLuint n, GLdepth zbuffer[],
+ const GLdepth z[], GLubyte mask[] )
+{
+ /* switch cases ordered from most frequent to less frequent */
+ switch (ctx->Depth.Func) {
+ case GL_LESS:
+ if (ctx->Depth.Mask) {
+ /* Update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ if (z[i] < zbuffer[i]) {
+ /* pass */
+ zbuffer[i] = z[i];
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ else {
+ /* Don't update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ if (z[i] < zbuffer[i]) {
+ /* pass */
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ break;
+ case GL_LEQUAL:
+ if (ctx->Depth.Mask) {
+ /* Update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ if (z[i] <= zbuffer[i]) {
+ /* pass */
+ zbuffer[i] = z[i];
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ else {
+ /* Don't update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ if (z[i] <= zbuffer[i]) {
+ /* pass */
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ break;
+ case GL_GEQUAL:
+ if (ctx->Depth.Mask) {
+ /* Update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ if (z[i] >= zbuffer[i]) {
+ /* pass */
+ zbuffer[i] = z[i];
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ else {
+ /* Don't update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ if (z[i] >= zbuffer[i]) {
+ /* pass */
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ break;
+ case GL_GREATER:
+ if (ctx->Depth.Mask) {
+ /* Update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ if (z[i] > zbuffer[i]) {
+ /* pass */
+ zbuffer[i] = z[i];
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ else {
+ /* Don't update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ if (z[i] > zbuffer[i]) {
+ /* pass */
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ break;
+ case GL_NOTEQUAL:
+ if (ctx->Depth.Mask) {
+ /* Update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ if (z[i] != zbuffer[i]) {
+ /* pass */
+ zbuffer[i] = z[i];
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ else {
+ /* Don't update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ if (z[i] != zbuffer[i]) {
+ /* pass */
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ break;
+ case GL_EQUAL:
+ if (ctx->Depth.Mask) {
+ /* Update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ if (z[i] == zbuffer[i]) {
+ /* pass */
+ zbuffer[i] = z[i];
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ else {
+ /* Don't update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ if (z[i] == zbuffer[i]) {
+ /* pass */
+ }
+ else {
+ /* fail */
+ mask[i] = 0;
+ }
+ }
+ }
+ }
+ break;
+ case GL_ALWAYS:
+ if (ctx->Depth.Mask) {
+ /* Update Z buffer */
+ GLuint i;
+ for (i=0; i<n; i++) {
+ if (mask[i]) {
+ zbuffer[i] = z[i];
+ }
+ }
+ }
+ else {
+ /* Don't update Z buffer or mask */
+ }
+ break;
+ case GL_NEVER:
+ /* depth test never passes */
+ BZERO(mask, n * sizeof(GLubyte));
+ break;
+ default:
+ gl_problem(ctx, "Bad depth func in hardware_depth_test_pixels");
+ }
+}
+
+
+
+void
+_mesa_depth_test_pixels( GLcontext *ctx,
+ GLuint n, const GLint x[], const GLint y[],
+ const GLdepth z[], GLubyte mask[] )
+{
+ if (ctx->Driver.ReadDepthPixels) {
+ /* read depth values from hardware Z buffer */
+ GLdepth zbuffer[PB_SIZE];
+ (*ctx->Driver.ReadDepthPixels)(ctx, n, x, y, zbuffer);
+
+ hardware_depth_test_pixels( ctx, n, zbuffer, z, mask );
+
+ /* update hardware Z buffer with new values */
+ assert(ctx->Driver.WriteDepthPixels);
+ (*ctx->Driver.WriteDepthPixels)(ctx, n, x, y, zbuffer, mask );
}
else {
- /* clear whole buffer */
- if (sizeof(GLdepth)==2 && (clear_value&0xff)==(clear_value>>8)) {
- /* lower and upper bytes of clear_value are same, use MEMSET */
- MEMSET( ctx->DrawBuffer->Depth, clear_value&0xff,
- 2*ctx->DrawBuffer->Width*ctx->DrawBuffer->Height);
+ /* software depth testing */
+ if (ctx->Visual->DepthBits <= 16)
+ software_depth_test_pixels16(ctx, n, x, y, z, mask);
+ else
+ software_depth_test_pixels32(ctx, n, x, y, z, mask);
+ }
+}
+
+
+
+
+
+/**********************************************************************/
+/***** Read Depth Buffer *****/
+/**********************************************************************/
+
+
+/*
+ * Return a span of depth values from the depth buffer as floats in [0,1].
+ * This is used for both hardware and software depth buffers.
+ * Input: n - how many pixels
+ * x,y - location of first pixel
+ * Output: depth - the array of depth values
+ */
+void
+_mesa_read_depth_span_float( GLcontext* ctx,
+ GLuint n, GLint x, GLint y, GLfloat depth[] )
+{
+ const GLfloat scale = 1.0F / ctx->Visual->DepthMaxF;
+
+ if (ctx->DrawBuffer->DepthBuffer) {
+ /* read from software depth buffer */
+ if (ctx->Visual->DepthBits <= 16) {
+ const GLushort *zptr = Z_ADDRESS16( ctx, x, y );
+ GLuint i;
+ for (i = 0; i < n; i++) {
+ depth[i] = (GLfloat) zptr[i] * scale;
+ }
}
else {
- GLdepth *d = ctx->DrawBuffer->Depth;
- GLint n = ctx->DrawBuffer->Width * ctx->DrawBuffer->Height;
- while (n>=16) {
- d[0] = clear_value; d[1] = clear_value;
- d[2] = clear_value; d[3] = clear_value;
- d[4] = clear_value; d[5] = clear_value;
- d[6] = clear_value; d[7] = clear_value;
- d[8] = clear_value; d[9] = clear_value;
- d[10] = clear_value; d[11] = clear_value;
- d[12] = clear_value; d[13] = clear_value;
- d[14] = clear_value; d[15] = clear_value;
- d += 16;
- n -= 16;
- }
- while (n>0) {
- *d++ = clear_value;
- n--;
+ const GLuint *zptr = Z_ADDRESS32( ctx, x, y );
+ GLuint i;
+ for (i = 0; i < n; i++) {
+ depth[i] = (GLfloat) zptr[i] * scale;
}
}
}
+ else if (ctx->Driver.ReadDepthSpan) {
+ /* read from hardware depth buffer */
+ GLdepth d[MAX_WIDTH];
+ GLuint i;
+ assert(n <= MAX_WIDTH);
+ (*ctx->Driver.ReadDepthSpan)( ctx, n, x, y, d );
+ for (i = 0; i < n; i++) {
+ depth[i] = d[i] * scale;
+ }
+ }
+ else {
+ /* no depth buffer */
+ BZERO(depth, n * sizeof(GLfloat));
+ }
+}
+
+
+
+/**********************************************************************/
+/***** Allocate and Clear Depth Buffer *****/
+/**********************************************************************/
+
+
+
+/*
+ * Allocate a new depth buffer. If there's already a depth buffer allocated
+ * it will be free()'d. The new depth buffer will be uniniitalized.
+ * This function is only called through Driver.alloc_depth_buffer.
+ */
+void
+_mesa_alloc_depth_buffer( GLcontext *ctx )
+{
+ /* deallocate current depth buffer if present */
+ if (ctx->DrawBuffer->UseSoftwareDepthBuffer) {
+ GLint bytesPerValue;
+
+ if (ctx->DrawBuffer->DepthBuffer) {
+ FREE(ctx->DrawBuffer->DepthBuffer);
+ ctx->DrawBuffer->DepthBuffer = NULL;
+ }
+
+ /* allocate new depth buffer, but don't initialize it */
+ if (ctx->Visual->DepthBits <= 16)
+ bytesPerValue = sizeof(GLushort);
+ else
+ bytesPerValue = sizeof(GLuint);
+
+ ctx->DrawBuffer->DepthBuffer = MALLOC( ctx->DrawBuffer->Width
+ * ctx->DrawBuffer->Height
+ * bytesPerValue );
+
+ if (!ctx->DrawBuffer->DepthBuffer) {
+ /* out of memory */
+ ctx->Depth.Test = GL_FALSE;
+ ctx->NewState |= NEW_RASTER_OPS;
+ gl_error( ctx, GL_OUT_OF_MEMORY, "Couldn't allocate depth buffer" );
+ }
+ }
}
+
+/*
+ * Clear the depth buffer. If the depth buffer doesn't exist yet we'll
+ * allocate it now.
+ * This function is only called through Driver.clear_depth_buffer.
+ */
+void
+_mesa_clear_depth_buffer( GLcontext *ctx )
+{
+ if (ctx->Visual->DepthBits == 0
+ || !ctx->DrawBuffer->DepthBuffer
+ || !ctx->Depth.Mask) {
+ /* no depth buffer, or writing to it is disabled */
+ return;
+ }
+
+ /* The loops in this function have been written so the IRIX 5.3
+ * C compiler can unroll them. Hopefully other compilers can too!
+ */
+
+ if (ctx->Scissor.Enabled) {
+ /* only clear scissor region */
+ if (ctx->Visual->DepthBits <= 16) {
+ const GLushort clearValue = (GLushort) (ctx->Depth.Clear * ctx->Visual->DepthMax);
+ const GLint rows = ctx->DrawBuffer->Ymax - ctx->DrawBuffer->Ymin + 1;
+ const GLint width = ctx->DrawBuffer->Width;
+ GLushort *dRow = (GLushort *) ctx->DrawBuffer->DepthBuffer
+ + ctx->DrawBuffer->Ymin * width + ctx->DrawBuffer->Xmin;
+ GLint i, j;
+ for (i = 0; i < rows; i++) {
+ for (j = 0; j < width; j++) {
+ dRow[j] = clearValue;
+ }
+ dRow += width;
+ }
+ }
+ else {
+ const GLuint clearValue = (GLuint) (ctx->Depth.Clear * ctx->Visual->DepthMax);
+ const GLint rows = ctx->DrawBuffer->Ymax - ctx->DrawBuffer->Ymin + 1;
+ const GLint width = ctx->DrawBuffer->Width;
+ GLuint *dRow = (GLuint *) ctx->DrawBuffer->DepthBuffer
+ + ctx->DrawBuffer->Ymin * width + ctx->DrawBuffer->Xmin;
+ GLint i, j;
+ for (i = 0; i < rows; i++) {
+ for (j = 0; j < width; j++) {
+ dRow[j] = clearValue;
+ }
+ dRow += width;
+ }
+ }
+ }
+ else {
+ /* clear whole buffer */
+ if (ctx->Visual->DepthBits <= 16) {
+ const GLushort clearValue = (GLushort) (ctx->Depth.Clear * ctx->Visual->DepthMax);
+ if ((clearValue & 0xff) == (clearValue >> 8)) {
+ if (clearValue == 0) {
+ BZERO(ctx->DrawBuffer->DepthBuffer,
+ 2*ctx->DrawBuffer->Width*ctx->DrawBuffer->Height);
+ }
+ else {
+ /* lower and upper bytes of clear_value are same, use MEMSET */
+ MEMSET( ctx->DrawBuffer->DepthBuffer, clearValue & 0xff,
+ 2 * ctx->DrawBuffer->Width * ctx->DrawBuffer->Height);
+ }
+ }
+ else {
+ GLushort *d = (GLushort *) ctx->DrawBuffer->DepthBuffer;
+ GLint n = ctx->DrawBuffer->Width * ctx->DrawBuffer->Height;
+ while (n >= 16) {
+ d[0] = clearValue; d[1] = clearValue;
+ d[2] = clearValue; d[3] = clearValue;
+ d[4] = clearValue; d[5] = clearValue;
+ d[6] = clearValue; d[7] = clearValue;
+ d[8] = clearValue; d[9] = clearValue;
+ d[10] = clearValue; d[11] = clearValue;
+ d[12] = clearValue; d[13] = clearValue;
+ d[14] = clearValue; d[15] = clearValue;
+ d += 16;
+ n -= 16;
+ }
+ while (n > 0) {
+ *d++ = clearValue;
+ n--;
+ }
+ }
+ }
+ else {
+ /* >16 bit depth buffer */
+ const GLuint clearValue = (GLuint) (ctx->Depth.Clear * ctx->Visual->DepthMax);
+ if (clearValue == 0) {
+ BZERO(ctx->DrawBuffer->DepthBuffer,
+ ctx->DrawBuffer->Width*ctx->DrawBuffer->Height*sizeof(GLuint));
+ }
+ else {
+ GLint n = ctx->DrawBuffer->Width * ctx->DrawBuffer->Height;
+ GLuint *d = (GLuint *) ctx->DrawBuffer->DepthBuffer;
+ while (n >= 16) {
+ d[0] = clearValue; d[1] = clearValue;
+ d[2] = clearValue; d[3] = clearValue;
+ d[4] = clearValue; d[5] = clearValue;
+ d[6] = clearValue; d[7] = clearValue;
+ d[8] = clearValue; d[9] = clearValue;
+ d[10] = clearValue; d[11] = clearValue;
+ d[12] = clearValue; d[13] = clearValue;
+ d[14] = clearValue; d[15] = clearValue;
+ d += 16;
+ n -= 16;
+ }
+ while (n > 0) {
+ *d++ = clearValue;
+ n--;
+ }
+ }
+ }
+ }
+}