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/*
* Test GL_NV_conditional_render
*
* Brian Paul
* 30 Dec 2009
*
* 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
* THE AUTHORS 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 <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <GL/glew.h>
#include <GL/glut.h>
#define TEST_DISPLAY_LISTS 0
static GLboolean Anim = GL_TRUE;
static GLfloat Xpos = 0;
static GLuint OccQuery;
static GLint Win = 0;
static void Idle(void)
{
static int lastTime = 0;
static int sign = +1;
int time = glutGet(GLUT_ELAPSED_TIME);
float step;
if (lastTime == 0)
lastTime = time;
else if (time - lastTime < 20) /* 50Hz update */
return;
step = (time - lastTime) / 1000.0 * sign;
lastTime = time;
Xpos += step;
if (Xpos > 2.5) {
Xpos = 2.5;
sign = -1;
}
else if (Xpos < -2.5) {
Xpos = -2.5;
sign = +1;
}
glutPostRedisplay();
}
static void Display( void )
{
glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
glEnable(GL_DEPTH_TEST);
glMatrixMode( GL_PROJECTION );
glLoadIdentity();
glFrustum( -1.0, 1.0, -1.0, 1.0, 5.0, 25.0 );
glMatrixMode( GL_MODELVIEW );
glLoadIdentity();
glTranslatef( 0.0, 0.0, -15.0 );
/* draw the occluding polygons */
glColor3f(0, 0.6, 0.8);
glBegin(GL_QUADS);
glVertex2f(-1.6, -1.5);
glVertex2f(-0.4, -1.5);
glVertex2f(-0.4, 1.5);
glVertex2f(-1.6, 1.5);
glVertex2f( 0.4, -1.5);
glVertex2f( 1.6, -1.5);
glVertex2f( 1.6, 1.5);
glVertex2f( 0.4, 1.5);
glEnd();
/* draw the test polygon with occlusion testing */
glPushMatrix();
glTranslatef(Xpos, 0, -0.5);
glScalef(0.3, 0.3, 1.0);
glRotatef(-90.0 * Xpos, 0, 0, 1);
#if TEST_DISPLAY_LISTS
glNewList(10, GL_COMPILE);
glBeginQueryARB(GL_SAMPLES_PASSED_ARB, OccQuery);
glEndList();
glCallList(10);
#else
glBeginQueryARB(GL_SAMPLES_PASSED_ARB, OccQuery);
#endif
glColorMask(0, 0, 0, 0);
glDepthMask(GL_FALSE);
glBegin(GL_POLYGON);
glVertex3f(-1, -1, 0);
glVertex3f( 1, -1, 0);
glVertex3f( 1, 1, 0);
glVertex3f(-1, 1, 0);
glEnd();
#if TEST_DISPLAY_LISTS
glNewList(11, GL_COMPILE);
glEndQueryARB(GL_SAMPLES_PASSED_ARB);
glEndList();
glCallList(11);
#else
glEndQueryARB(GL_SAMPLES_PASSED_ARB);
#endif
glColorMask(1, 1, 1, 1);
glDepthMask(GL_TRUE);
/* Note: disable depth test here so that we'll always see the orange
* box, except when it's totally culled.
*/
glDisable(GL_DEPTH_TEST);
glBeginConditionalRenderNV(OccQuery, GL_QUERY_WAIT_NV);
/* draw the orange rect, so we can see what's going on */
glColor3f(0.8, 0.5, 0);
glBegin(GL_POLYGON);
glVertex3f(-1, -1, 0);
glVertex3f( 1, -1, 0);
glVertex3f( 1, 1, 0);
glVertex3f(-1, 1, 0);
glEnd();
glEndConditionalRenderNV();
/* always draw white outline around orange box */
glColor3f(1.0, 1.0, 1.0);
glBegin(GL_LINE_LOOP);
glVertex3f(-1, -1, 0);
glVertex3f( 1, -1, 0);
glVertex3f( 1, 1, 0);
glVertex3f(-1, 1, 0);
glEnd();
glPopMatrix();
glutSwapBuffers();
}
static void Reshape( int width, int height )
{
glViewport( 0, 0, width, height );
}
static void Key( unsigned char key, int x, int y )
{
(void) x;
(void) y;
switch (key) {
case 27:
glDeleteQueriesARB(1, &OccQuery);
glutDestroyWindow(Win);
exit(0);
break;
case ' ':
Anim = !Anim;
if (Anim)
glutIdleFunc(Idle);
else
glutIdleFunc(NULL);
break;
}
glutPostRedisplay();
}
static void SpecialKey( int key, int x, int y )
{
const GLfloat step = 0.1;
(void) x;
(void) y;
switch (key) {
case GLUT_KEY_LEFT:
Xpos -= step;
break;
case GLUT_KEY_RIGHT:
Xpos += step;
break;
}
glutPostRedisplay();
}
static void Init( void )
{
if (!glutExtensionSupported("GL_ARB_occlusion_query") ||
!glutExtensionSupported("GL_NV_conditional_render")) {
printf("Sorry, this demo requires the extensions:\n");
printf(" GL_ARB_occlusion_query\n");
printf(" GL_NV_conditional_render\n");
exit(-1);
}
glGenQueriesARB(1, &OccQuery);
assert(OccQuery > 0);
}
int main( int argc, char *argv[] )
{
glutInitWindowSize( 400, 400 );
glutInit( &argc, argv );
glutInitDisplayMode( GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH );
Win = glutCreateWindow(argv[0]);
glewInit();
glutReshapeFunc( Reshape );
glutKeyboardFunc( Key );
glutSpecialFunc( SpecialKey );
glutIdleFunc( Idle );
glutDisplayFunc( Display );
Init();
glutMainLoop();
return 0;
}
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