xenocara/dist/Mesa/progs/perf/drawoverhead.c

138 lines
3.4 KiB
C

/*
* 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).
*
* 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();
}
void
PerfNextRound(void)
{
}
/** Called from test harness/main */
void
PerfDraw(void)
{
double rate0, rate1, rate2, overhead;
rate0 = PerfMeasureRate(DrawNoStateChange);
perf_printf(" Draw only: %s draws/second\n",
PerfHumanFloat(rate0));
rate1 = PerfMeasureRate(DrawNopStateChange);
overhead = 1000.0 * (1.0 / rate1 - 1.0 / rate0);
perf_printf(" Draw w/ nop state change: %s draws/sec (overhead: %f ms/draw)\n",
PerfHumanFloat(rate1), overhead);
rate2 = PerfMeasureRate(DrawStateChange);
overhead = 1000.0 * (1.0 / rate2 - 1.0 / rate0);
perf_printf(" Draw w/ state change: %s draws/sec (overhead: %f ms/draw)\n",
PerfHumanFloat(rate2), overhead);
exit(0);
}