Added MesaLib-7.6

1 files changed, 1429 insertions, 0 deletions

diff --git a/mesalib/src/mesa/swrast/s_depth.c b/mesalib/src/mesa/swrast/s_depth.c
new file mode 100644
index 000000000..26e23f02d
--- /dev/null
+++ b/mesalib/src/mesa/swrast/s_depth.c
@@ -0,0 +1,1429 @@
+/*
+ * Mesa 3-D graphics library
+ * Version:  7.2.1
+ *
+ * Copyright (C) 1999-2008  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/macros.h"
+#include "main/imports.h"
+#include "main/fbobject.h"
+
+#include "s_depth.h"
+#include "s_context.h"
+#include "s_span.h"
+
+
+/**
+ * Do depth test for a horizontal span of fragments.
+ * Input:  zbuffer - array of z values in the zbuffer
+ *         z - array of fragment z values
+ * Return:  number of fragments which pass the test.
+ */
+static GLuint
+depth_test_span16( GLcontext *ctx, GLuint n,
+                   GLushort zbuffer[], const GLuint z[], GLubyte mask[] )
+{
+   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]) {
+		  if (z[i] < zbuffer[i]) {
+		     /* pass */
+		     zbuffer[i] = z[i];
+		     passed++;
+		  }
+		  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 */
+		     passed++;
+		  }
+		  else {
+		     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]) {
+		     zbuffer[i] = z[i];
+		     passed++;
+		  }
+		  else {
+		     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 */
+		     passed++;
+		  }
+		  else {
+		     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]) {
+		     zbuffer[i] = z[i];
+		     passed++;
+		  }
+		  else {
+		     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 */
+		     passed++;
+		  }
+		  else {
+		     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]) {
+		     zbuffer[i] = z[i];
+		     passed++;
+		  }
+		  else {
+		     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 */
+		     passed++;
+		  }
+		  else {
+		     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]) {
+		     zbuffer[i] = z[i];
+		     passed++;
+		  }
+		  else {
+		     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 */
+		     passed++;
+		  }
+		  else {
+		     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]) {
+		     zbuffer[i] = z[i];
+		     passed++;
+		  }
+		  else {
+		     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 */
+		     passed++;
+		  }
+		  else {
+		     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];
+		  passed++;
+	       }
+	    }
+	 }
+	 else {
+	    /* Don't update Z buffer or mask */
+	    passed = n;
+	 }
+	 break;
+      case GL_NEVER:
+         _mesa_bzero(mask, n * sizeof(GLubyte));
+	 break;
+      default:
+         _mesa_problem(ctx, "Bad depth func in depth_test_span16");
+   }
+
+   return passed;
+}
+
+
+static GLuint
+depth_test_span32( GLcontext *ctx, GLuint n,
+                   GLuint zbuffer[], const GLuint z[], GLubyte mask[] )
+{
+   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]) {
+		  if (z[i] < zbuffer[i]) {
+		     /* pass */
+		     zbuffer[i] = z[i];
+		     passed++;
+		  }
+		  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 */
+		     passed++;
+		  }
+		  else {
+		     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]) {
+		     zbuffer[i] = z[i];
+		     passed++;
+		  }
+		  else {
+		     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 */
+		     passed++;
+		  }
+		  else {
+		     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]) {
+		     zbuffer[i] = z[i];
+		     passed++;
+		  }
+		  else {
+		     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 */
+		     passed++;
+		  }
+		  else {
+		     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]) {
+		     zbuffer[i] = z[i];
+		     passed++;
+		  }
+		  else {
+		     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 */
+		     passed++;
+		  }
+		  else {
+		     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]) {
+		     zbuffer[i] = z[i];
+		     passed++;
+		  }
+		  else {
+		     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 */
+		     passed++;
+		  }
+		  else {
+		     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]) {
+		     zbuffer[i] = z[i];
+		     passed++;
+		  }
+		  else {
+		     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 */
+		     passed++;
+		  }
+		  else {
+		     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];
+		  passed++;
+	       }
+	    }
+	 }
+	 else {
+	    /* Don't update Z buffer or mask */
+	    passed = n;
+	 }
+	 break;
+      case GL_NEVER:
+         _mesa_bzero(mask, n * sizeof(GLubyte));
+	 break;
+      default:
+         _mesa_problem(ctx, "Bad depth func in depth_test_span32");
+   }
+
+   return passed;
+}
+
+
+
+/*
+ * Apply depth test to span of fragments.
+ */
+static GLuint
+depth_test_span( GLcontext *ctx, SWspan *span)
+{
+   struct gl_framebuffer *fb = ctx->DrawBuffer;
+   struct gl_renderbuffer *rb = fb->_DepthBuffer;
+   const GLint x = span->x;
+   const GLint y = span->y;
+   const GLuint count = span->end;
+   const GLuint *zValues = span->array->z;
+   GLubyte *mask = span->array->mask;
+   GLuint passed;
+
+   ASSERT((span->arrayMask & SPAN_XY) == 0);
+   ASSERT(span->arrayMask & SPAN_Z);
+   
+   if (rb->GetPointer(ctx, rb, 0, 0)) {
+      /* Directly access buffer */
+      if (rb->DataType == GL_UNSIGNED_SHORT) {
+         GLushort *zbuffer = (GLushort *) rb->GetPointer(ctx, rb, x, y);
+         passed = depth_test_span16(ctx, count, zbuffer, zValues, mask);
+      }
+      else {
+         GLuint *zbuffer = (GLuint *) rb->GetPointer(ctx, rb, x, y);
+         ASSERT(rb->DataType == GL_UNSIGNED_INT);
+         passed = depth_test_span32(ctx, count, zbuffer, zValues, mask);
+      }
+   }
+   else {
+      /* read depth values from buffer, test, write back */
+      if (rb->DataType == GL_UNSIGNED_SHORT) {
+         GLushort zbuffer[MAX_WIDTH];
+         rb->GetRow(ctx, rb, count, x, y, zbuffer);
+         passed = depth_test_span16(ctx, count, zbuffer, zValues, mask);
+         rb->PutRow(ctx, rb, count, x, y, zbuffer, mask);
+      }
+      else {
+         GLuint zbuffer[MAX_WIDTH];
+         ASSERT(rb->DataType == GL_UNSIGNED_INT);
+         rb->GetRow(ctx, rb, count, x, y, zbuffer);
+         passed = depth_test_span32(ctx, count, zbuffer, zValues, mask);
+         rb->PutRow(ctx, rb, count, x, y, zbuffer, mask);
+      }
+   }
+
+   if (passed < count) {
+      span->writeAll = GL_FALSE;
+   }
+   return passed;
+}
+
+
+
+#define Z_ADDRESS(X, Y)   (zStart + (Y) * stride + (X))
+
+
+/*
+ * Do depth testing for an array of fragments at assorted locations.
+ */
+static void
+direct_depth_test_pixels16(GLcontext *ctx, GLushort *zStart, GLuint stride,
+                           GLuint n, const GLint x[], const GLint y[],
+                           const GLuint 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]) {
+		  GLushort *zptr = Z_ADDRESS(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_ADDRESS(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_ADDRESS(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_ADDRESS(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_ADDRESS(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_ADDRESS(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_ADDRESS(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_ADDRESS(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_ADDRESS(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_ADDRESS(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_ADDRESS(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_ADDRESS(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_ADDRESS(x[i], y[i]);
+		  *zptr = z[i];
+	       }
+	    }
+	 }
+	 else {
+	    /* Don't update Z buffer or mask */
+	 }
+	 break;
+      case GL_NEVER:
+	 /* depth test never passes */
+         _mesa_bzero(mask, n * sizeof(GLubyte));
+	 break;
+      default:
+         _mesa_problem(ctx, "Bad depth func in direct_depth_test_pixels");
+   }
+}
+
+
+
+/*
+ * Do depth testing for an array of fragments with direct access to zbuffer.
+ */
+static void
+direct_depth_test_pixels32(GLcontext *ctx, GLuint *zStart, GLuint stride,
+                           GLuint n, const GLint x[], const GLint y[],
+                           const GLuint 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_ADDRESS(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_ADDRESS(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_ADDRESS(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_ADDRESS(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_ADDRESS(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_ADDRESS(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_ADDRESS(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_ADDRESS(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_ADDRESS(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_ADDRESS(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_ADDRESS(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_ADDRESS(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_ADDRESS(x[i], y[i]);
+		  *zptr = z[i];
+	       }
+	    }
+	 }
+	 else {
+	    /* Don't update Z buffer or mask */
+	 }
+	 break;
+      case GL_NEVER:
+	 /* depth test never passes */
+         _mesa_bzero(mask, n * sizeof(GLubyte));
+	 break;
+      default:
+         _mesa_problem(ctx, "Bad depth func in direct_depth_test_pixels");
+   }
+}
+
+
+
+
+static GLuint
+depth_test_pixels( GLcontext *ctx, SWspan *span )
+{
+   struct gl_framebuffer *fb = ctx->DrawBuffer;
+   struct gl_renderbuffer *rb = fb->_DepthBuffer;
+   const GLuint count = span->end;
+   const GLint *x = span->array->x;
+   const GLint *y = span->array->y;
+   const GLuint *z = span->array->z;
+   GLubyte *mask = span->array->mask;
+
+   if (rb->GetPointer(ctx, rb, 0, 0)) {
+      /* Directly access values */
+      if (rb->DataType == GL_UNSIGNED_SHORT) {
+         GLushort *zStart = (GLushort *) rb->Data;
+         GLuint stride = rb->Width;
+         direct_depth_test_pixels16(ctx, zStart, stride, count, x, y, z, mask);
+      }
+      else {
+         GLuint *zStart = (GLuint *) rb->Data;
+         GLuint stride = rb->Width;
+         ASSERT(rb->DataType == GL_UNSIGNED_INT);
+         direct_depth_test_pixels32(ctx, zStart, stride, count, x, y, z, mask);
+      }
+   }
+   else {
+      /* read depth values from buffer, test, write back */
+      if (rb->DataType == GL_UNSIGNED_SHORT) {
+         GLushort zbuffer[MAX_WIDTH];
+         _swrast_get_values(ctx, rb, count, x, y, zbuffer, sizeof(GLushort));
+         depth_test_span16(ctx, count, zbuffer, z, mask);
+         rb->PutValues(ctx, rb, count, x, y, zbuffer, mask);
+      }
+      else {
+         GLuint zbuffer[MAX_WIDTH];
+         ASSERT(rb->DataType == GL_UNSIGNED_INT);
+         _swrast_get_values(ctx, rb, count, x, y, zbuffer, sizeof(GLuint));
+         depth_test_span32(ctx, count, zbuffer, z, mask);
+         rb->PutValues(ctx, rb, count, x, y, zbuffer, mask);
+      }
+   }
+
+   return count; /* not really correct, but OK */
+}
+
+
+/**
+ * Apply depth (Z) buffer testing to the span.
+ * \return approx number of pixels that passed (only zero is reliable)
+ */
+GLuint
+_swrast_depth_test_span( GLcontext *ctx, SWspan *span)
+{
+   if (span->arrayMask & SPAN_XY)
+      return depth_test_pixels(ctx, span);
+   else
+      return depth_test_span(ctx, span);
+}
+
+
+/**
+ * GL_EXT_depth_bounds_test extension.
+ * Discard fragments depending on whether the corresponding Z-buffer
+ * values are outside the depth bounds test range.
+ * Note: we test the Z buffer values, not the fragment Z values!
+ * \return GL_TRUE if any fragments pass, GL_FALSE if no fragments pass
+ */
+GLboolean
+_swrast_depth_bounds_test( GLcontext *ctx, SWspan *span )
+{
+   struct gl_framebuffer *fb = ctx->DrawBuffer;
+   struct gl_renderbuffer *rb = fb->_DepthBuffer;
+   GLuint zMin = (GLuint) (ctx->Depth.BoundsMin * fb->_DepthMaxF + 0.5F);
+   GLuint zMax = (GLuint) (ctx->Depth.BoundsMax * fb->_DepthMaxF + 0.5F);
+   GLubyte *mask = span->array->mask;
+   const GLuint count = span->end;
+   GLuint i;
+   GLboolean anyPass = GL_FALSE;
+
+   if (rb->DataType == GL_UNSIGNED_SHORT) {
+      /* get 16-bit values */
+      GLushort zbuffer16[MAX_WIDTH], *zbuffer;
+      if (span->arrayMask & SPAN_XY) {
+         _swrast_get_values(ctx, rb, count, span->array->x, span->array->y,
+                            zbuffer16, sizeof(GLushort));
+         zbuffer = zbuffer16;
+      }
+      else {
+         zbuffer = (GLushort*) rb->GetPointer(ctx, rb, span->x, span->y);
+         if (!zbuffer) {
+            rb->GetRow(ctx, rb, count, span->x, span->y, zbuffer16);
+            zbuffer = zbuffer16;
+         }
+      }
+      assert(zbuffer);
+
+      /* Now do the tests */
+      for (i = 0; i < count; i++) {
+         if (mask[i]) {
+            if (zbuffer[i] < zMin || zbuffer[i] > zMax)
+               mask[i] = GL_FALSE;
+            else
+               anyPass = GL_TRUE;
+         }
+      }
+   }
+   else {
+      /* get 32-bit values */
+      GLuint zbuffer32[MAX_WIDTH], *zbuffer;
+      ASSERT(rb->DataType == GL_UNSIGNED_INT);
+      if (span->arrayMask & SPAN_XY) {
+         _swrast_get_values(ctx, rb, count, span->array->x, span->array->y,
+                            zbuffer32, sizeof(GLuint));
+         zbuffer = zbuffer32;
+      }
+      else {
+         zbuffer = (GLuint*) rb->GetPointer(ctx, rb, span->x, span->y);
+         if (!zbuffer) {
+            rb->GetRow(ctx, rb, count, span->x, span->y, zbuffer32);
+            zbuffer = zbuffer32;
+         }
+      }
+      assert(zbuffer);
+
+      /* Now do the tests */
+      for (i = 0; i < count; i++) {
+         if (mask[i]) {
+            if (zbuffer[i] < zMin || zbuffer[i] > zMax)
+               mask[i] = GL_FALSE;
+            else
+               anyPass = GL_TRUE;
+         }
+      }
+   }
+
+   return anyPass;
+}
+
+
+
+/**********************************************************************/
+/*****                      Read Depth Buffer                     *****/
+/**********************************************************************/
+
+
+/**
+ * Read a span of depth values from the given depth renderbuffer, returning
+ * the values as GLfloats.
+ * This function does clipping to prevent reading outside the depth buffer's
+ * bounds.  Though the clipping is redundant when we're called from
+ * _swrast_ReadPixels.
+ */
+void
+_swrast_read_depth_span_float( GLcontext *ctx, struct gl_renderbuffer *rb,
+                               GLint n, GLint x, GLint y, GLfloat depth[] )
+{
+   const GLfloat scale = 1.0F / ctx->DrawBuffer->_DepthMaxF;
+
+   if (!rb) {
+      /* really only doing this to prevent FP exceptions later */
+      _mesa_bzero(depth, n * sizeof(GLfloat));
+   }
+
+   ASSERT(rb->_BaseFormat == GL_DEPTH_COMPONENT);
+
+   if (y < 0 || y >= (GLint) rb->Height ||
+       x + n <= 0 || x >= (GLint) rb->Width) {
+      /* span is completely outside framebuffer */
+      _mesa_bzero(depth, n * sizeof(GLfloat));
+      return;
+   }
+
+   if (x < 0) {
+      GLint dx = -x;
+      GLint i;
+      for (i = 0; i < dx; i++)
+         depth[i] = 0.0;
+      x = 0;
+      n -= dx;
+      depth += dx;
+   }
+   if (x + n > (GLint) rb->Width) {
+      GLint dx = x + n - (GLint) rb->Width;
+      GLint i;
+      for (i = 0; i < dx; i++)
+         depth[n - i - 1] = 0.0;
+      n -= dx;
+   }
+   if (n <= 0) {
+      return;
+   }
+
+   if (rb->DataType == GL_UNSIGNED_INT) {
+      GLuint temp[MAX_WIDTH];
+      GLint i;
+      rb->GetRow(ctx, rb, n, x, y, temp);
+      for (i = 0; i < n; i++) {
+         depth[i] = temp[i] * scale;
+      }
+   }
+   else if (rb->DataType == GL_UNSIGNED_SHORT) {
+      GLushort temp[MAX_WIDTH];
+      GLint i;
+      rb->GetRow(ctx, rb, n, x, y, temp);
+      for (i = 0; i < n; i++) {
+         depth[i] = temp[i] * scale;
+      }
+   }
+   else {
+      _mesa_problem(ctx, "Invalid depth renderbuffer data type");
+   }
+}
+
+
+/**
+ * As above, but return 32-bit GLuint values.
+ */
+void
+_swrast_read_depth_span_uint( GLcontext *ctx, struct gl_renderbuffer *rb,
+                              GLint n, GLint x, GLint y, GLuint depth[] )
+{
+   if (!rb) {
+      /* really only doing this to prevent FP exceptions later */
+      _mesa_bzero(depth, n * sizeof(GLfloat));
+   }
+
+   ASSERT(rb->_BaseFormat == GL_DEPTH_COMPONENT);
+
+   if (y < 0 || y >= (GLint) rb->Height ||
+       x + n <= 0 || x >= (GLint) rb->Width) {
+      /* span is completely outside framebuffer */
+      _mesa_bzero(depth, n * sizeof(GLfloat));
+      return;
+   }
+
+   if (x < 0) {
+      GLint dx = -x;
+      GLint i;
+      for (i = 0; i < dx; i++)
+         depth[i] = 0;
+      x = 0;
+      n -= dx;
+      depth += dx;
+   }
+   if (x + n > (GLint) rb->Width) {
+      GLint dx = x + n - (GLint) rb->Width;
+      GLint i;
+      for (i = 0; i < dx; i++)
+         depth[n - i - 1] = 0;
+      n -= dx;
+   }
+   if (n <= 0) {
+      return;
+   }
+
+   if (rb->DataType == GL_UNSIGNED_INT) {
+      rb->GetRow(ctx, rb, n, x, y, depth);
+      if (rb->DepthBits < 32) {
+         GLuint shift = 32 - rb->DepthBits;
+         GLint i;
+         for (i = 0; i < n; i++) {
+            GLuint z = depth[i];
+            depth[i] = z << shift; /* XXX lsb bits? */
+         }
+      }
+   }
+   else if (rb->DataType == GL_UNSIGNED_SHORT) {
+      GLushort temp[MAX_WIDTH];
+      GLint i;
+      rb->GetRow(ctx, rb, n, x, y, temp);
+      if (rb->DepthBits == 16) {
+         for (i = 0; i < n; i++) {
+            GLuint z = temp[i];
+            depth[i] = (z << 16) | z;
+         }
+      }
+      else {
+         GLuint shift = 16 - rb->DepthBits;
+         for (i = 0; i < n; i++) {
+            GLuint z = temp[i];
+            depth[i] = (z << (shift + 16)) | (z << shift); /* XXX lsb bits? */
+         }
+      }
+   }
+   else {
+      _mesa_problem(ctx, "Invalid depth renderbuffer data type");
+   }
+}
+
+
+
+/**
+ * Clear the given z/depth renderbuffer.
+ */
+void
+_swrast_clear_depth_buffer( GLcontext *ctx, struct gl_renderbuffer *rb )
+{
+   GLuint clearValue;
+   GLint x, y, width, height;
+
+   if (!rb || !ctx->Depth.Mask) {
+      /* no depth buffer, or writing to it is disabled */
+      return;
+   }
+
+   /* compute integer clearing value */
+   if (ctx->Depth.Clear == 1.0) {
+      clearValue = ctx->DrawBuffer->_DepthMax;
+   }
+   else {
+      clearValue = (GLuint) (ctx->Depth.Clear * ctx->DrawBuffer->_DepthMaxF);
+   }
+
+   assert(rb->_BaseFormat == GL_DEPTH_COMPONENT);
+
+   /* 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 is possible.  Either this is just malloc'd
+       * memory, or perhaps the driver mmap'd the zbuffer memory.
+       */
+      if (rb->DataType == GL_UNSIGNED_SHORT) {
+         if ((clearValue & 0xff) == ((clearValue >> 8) & 0xff) &&
+             ((GLushort *) rb->GetPointer(ctx, rb, 0, 0) + width ==
+              (GLushort *) rb->GetPointer(ctx, rb, 0, 1))) {
+            /* optimized case */
+            GLushort *dst = (GLushort *) rb->GetPointer(ctx, rb, x, y);
+            GLuint len = width * height * sizeof(GLushort);
+            _mesa_memset(dst, (clearValue & 0xff), len);
+         }
+         else {
+            /* general case */
+            GLint i, j;
+            for (i = 0; i < height; i++) {
+               GLushort *dst = (GLushort *) rb->GetPointer(ctx, rb, x, y + i);
+               for (j = 0; j < width; j++) {
+                  dst[j] = clearValue;
+               }
+            }
+         }
+      }
+      else {
+         GLint i, j;
+         ASSERT(rb->DataType == GL_UNSIGNED_INT);
+         for (i = 0; i < height; i++) {
+            GLuint *dst = (GLuint *) rb->GetPointer(ctx, rb, x, y + i);
+            for (j = 0; j < width; j++) {
+               dst[j] = clearValue;
+            }
+         }
+      }
+   }
+   else {
+      /* Direct access not possible.  Use PutRow to write new values. */
+      if (rb->DataType == GL_UNSIGNED_SHORT) {
+         GLushort clearVal16 = (GLushort) (clearValue & 0xffff);
+         GLint i;
+         for (i = 0; i < height; i++) {
+            rb->PutMonoRow(ctx, rb, width, x, y + i, &clearVal16, NULL);
+         }
+      }
+      else if (rb->DataType == GL_UNSIGNED_INT) {
+         GLint i;
+         ASSERT(sizeof(clearValue) == sizeof(GLuint));
+         for (i = 0; i < height; i++) {
+            rb->PutMonoRow(ctx, rb, width, x, y + i, &clearValue, NULL);
+         }
+      }
+      else {
+         _mesa_problem(ctx, "bad depth renderbuffer DataType");
+      }
+   }
+}