1 files changed, 169 insertions, 0 deletions
diff --git a/progs/perf/readpixels.c b/progs/perf/readpixels.c
new file mode 100644
index 0000000000..ac7dc426e9
--- /dev/null
+++ b/progs/perf/readpixels.c
@@ -0,0 +1,169 @@
+/*
+ * Copyright (C) 2009  VMware, Inc.  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
+ * VMWARE 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.
+ */
+
+/**
+ * Measure glReadPixels speed.
+ * XXX also read into a PBO?
+ * XXX also read from FBOs?
+ *
+ * Brian Paul
+ * 23 Sep 2009
+ */
+
+#include <string.h>
+#include <assert.h>
+#include "glmain.h"
+#include "common.h"
+
+int WinWidth = 1000, WinHeight = 1000;
+
+static GLuint VBO;
+
+static const GLboolean DrawPoint = GL_TRUE;
+static const GLboolean BufferSubDataInHalves = GL_TRUE;
+
+static const GLfloat Vertex0[2] = { 0.0, 0.0 };
+
+static GLenum HaveDepthStencil;
+
+static GLenum ReadFormat, ReadType;
+static GLint ReadWidth, ReadHeight;
+static GLvoid *ReadBuffer;
+
+
+/** Called from test harness/main */
+void
+PerfInit(void)
+{
+   /* setup VBO */
+   glGenBuffersARB(1, &VBO);
+   glBindBufferARB(GL_ARRAY_BUFFER_ARB, VBO);
+   glBufferDataARB(GL_ARRAY_BUFFER_ARB, sizeof(Vertex0), Vertex0, GL_STATIC_DRAW_ARB);
+   glVertexPointer(2, GL_FLOAT, sizeof(Vertex0), (void *) 0);
+   glEnableClientState(GL_VERTEX_ARRAY);
+
+   glPixelStorei(GL_PACK_ALIGNMENT, 1);
+
+   HaveDepthStencil = PerfExtensionSupported("GL_EXT_packed_depth_stencil");
+
+   glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
+   glEnable(GL_DEPTH_TEST);
+   glEnable(GL_STENCIL_TEST);
+}
+
+
+static void
+ReadPixels(unsigned count)
+{
+   unsigned i;
+   for (i = 0; i < count; i++) {
+      /* read from random pos */
+      GLint x, y;
+
+      x = WinWidth - ReadWidth;
+      y = WinHeight - ReadHeight;
+      if (x > 0)
+         x = rand() % x;
+      if (y > 0)
+         y = rand() % y;
+
+      if (DrawPoint)
+         glDrawArrays(GL_POINTS, 0, 1);
+
+      glReadPixels(x, y, ReadWidth, ReadHeight,
+                   ReadFormat, ReadType, ReadBuffer);
+   }
+   glFinish();
+}
+
+
+static const GLsizei Sizes[] = {
+   10,
+   100,
+   500,
+   1000,
+   0
+};
+
+
+static const struct {
+   GLenum format;
+   GLenum type;
+   const char *name;
+   GLuint pixel_size;
+} DstFormats[] = {
+   { GL_RGBA, GL_UNSIGNED_BYTE,           "RGBA/ubyte", 4 },
+   { GL_BGRA, GL_UNSIGNED_BYTE,           "BGRA/ubyte", 4 },
+   { GL_RGB, GL_UNSIGNED_SHORT_5_6_5,     "RGB/565", 2 },
+   { GL_LUMINANCE, GL_UNSIGNED_BYTE,      "L/ubyte", 1 },
+   { GL_DEPTH_COMPONENT, GL_UNSIGNED_INT, "Z/uint", 4 },
+   { GL_DEPTH_STENCIL_EXT, GL_UNSIGNED_INT_24_8_EXT, "Z+S/uint", 4 },
+   { 0, 0, NULL, 0 }
+};
+
+
+
+/** Called from test harness/main */
+void
+PerfNextRound(void)
+{
+}
+
+
+/** Called from test harness/main */
+void
+PerfDraw(void)
+{
+   double rate, mbPerSec;
+   int fmt, sz;
+
+   /* loop over formats */
+   for (fmt = 0; DstFormats[fmt].format; fmt++) {
+      ReadFormat = DstFormats[fmt].format;
+      ReadType = DstFormats[fmt].type;
+
+      /* loop over sizes */
+      for (sz = 0; Sizes[sz]; sz++) {
+         int imgSize;
+
+         ReadWidth = ReadHeight = Sizes[sz];
+         imgSize = ReadWidth * ReadHeight * DstFormats[fmt].pixel_size;
+         ReadBuffer = malloc(imgSize);
+
+         if (ReadFormat == GL_DEPTH_STENCIL_EXT && !HaveDepthStencil) {
+            rate = 0.0;
+            mbPerSec = 0.0;
+         }
+         else {
+            rate = PerfMeasureRate(ReadPixels);
+            mbPerSec = rate * imgSize / (1024.0 * 1024.0);
+         }
+
+         perf_printf("glReadPixels(%d x %d, %s): %.1f images/sec, %.1f Mpixels/sec\n",
+                     ReadWidth, ReadHeight,
+                     DstFormats[fmt].name, rate, mbPerSec);
+
+         free(ReadBuffer);
+      }
+   }
+
+   exit(0);
+}