1 files changed, 134 insertions, 0 deletions
diff --git a/progs/perf/drawoverhead.c b/progs/perf/drawoverhead.c
new file mode 100644
index 00000000000..c1e166e7462
--- /dev/null
+++ b/progs/perf/drawoverhead.c
@@ -0,0 +1,134 @@
+/*
+ * 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 drawing overhead
+ *
+ * This is the first in a series of simple performance benchmarks.
+ * The code in this file should be as simple as possible to make it
+ * easily portable to other APIs.
+ *
+ * All the window-system stuff should be contained in glmain.c (or TBDmain.c).
+ * All the re-usable, generic code should be in common.c (XXX not done yet).
+ *
+ * Brian Paul
+ * 15 Sep 2009
+ */
+
+#include "glmain.h"
+#include "common.h"
+
+
+int WinWidth = 100, WinHeight = 100;
+
+static GLuint VBO;
+
+struct vertex
+{
+   GLfloat x, y;
+};
+
+static const struct vertex vertices[4] = {
+   { -1.0, -1.0 },
+   {  1.0, -1.0 },
+   {  1.0,  1.0 },
+   { -1.0,  1.0 }
+};
+
+
+/** Called from test harness/main */
+void
+PerfInit(void)
+{
+   /* setup VBO w/ vertex data */
+   glGenBuffersARB(1, &VBO);
+   glBindBufferARB(GL_ARRAY_BUFFER_ARB, VBO);
+   glBufferDataARB(GL_ARRAY_BUFFER_ARB,
+                   sizeof(vertices), vertices, GL_STATIC_DRAW_ARB);
+   glVertexPointer(2, GL_FLOAT, sizeof(struct vertex), (void *) 0);
+   glEnableClientState(GL_VERTEX_ARRAY);
+
+   /* misc GL state */
+   glAlphaFunc(GL_ALWAYS, 0.0);
+}
+
+
+static void
+DrawNoStateChange(unsigned count)
+{
+   unsigned i;
+   for (i = 0; i < count; i++) {
+      glDrawArrays(GL_POINTS, 0, 4);
+   }
+   glFinish();
+}
+
+
+static void
+DrawNopStateChange(unsigned count)
+{
+   unsigned i;
+   for (i = 0; i < count; i++) {
+      glDisable(GL_ALPHA_TEST);
+      glDrawArrays(GL_POINTS, 0, 4);
+   }
+   glFinish();
+}
+
+
+static void
+DrawStateChange(unsigned count)
+{
+   unsigned i;
+   for (i = 0; i < count; i++) {
+      if (i & 1)
+         glEnable(GL_TEXTURE_GEN_S);
+      else
+         glDisable(GL_TEXTURE_GEN_S);
+      glDrawArrays(GL_POINTS, 0, 4);
+   }
+   glFinish();
+}
+
+
+/** Called from test harness/main */
+void
+PerfDraw(void)
+{
+   double rate0, rate1, rate2, overhead;
+
+   rate0 = PerfMeasureRate(DrawNoStateChange);
+   perf_printf("   Draw only: %.1f draws/second\n", rate0);
+   
+
+   rate1 = PerfMeasureRate(DrawNopStateChange);
+   overhead = 1000.0 * (1.0 / rate1 - 1.0 / rate0);
+   perf_printf("   Draw w/ nop state change: %.1f draws/sec (overhead: %f ms/draw)\n",
+               rate1, overhead);
+
+   rate2 = PerfMeasureRate(DrawStateChange);
+   overhead = 1000.0 * (1.0 / rate2 - 1.0 / rate0);
+   perf_printf("   Draw w/ state change: %.1f draws/sec (overhead: %f ms/draw)\n",
+               rate2, overhead);
+
+   exit(0);
+}
+