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/*
* Test NPOT textures with the GL_ARB_texture_non_power_of_two extension.
* Brian Paul
* 2 July 2003
*/
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <GL/glew.h>
#include <GL/glut.h>
#include "../util/readtex.c"
#define IMAGE_FILE "../images/girl.rgb"
static GLfloat Zrot = 0;
static void Display( void )
{
glClear( GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT );
glPushMatrix();
glRotatef(Zrot, 0, 0, 1);
glBegin(GL_POLYGON);
glTexCoord2f(0, 0);
glVertex2f(-1, -1);
glTexCoord2f(1, 0);
glVertex2f(1, -1);
glTexCoord2f(1, 1);
glVertex2f(1, 1);
glTexCoord2f(0, 1);
glVertex2f(-1, 1);
glEnd();
glPopMatrix();
glutSwapBuffers();
}
static void Reshape( int width, int height )
{
glViewport( 0, 0, width, height );
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, -7.0 );
}
static void Key( unsigned char key, int x, int y )
{
(void) x;
(void) y;
switch (key) {
case 'z':
Zrot -= 1.0;
break;
case 'Z':
Zrot += 1.0;
break;
case 27:
exit(0);
break;
}
glutPostRedisplay();
}
static void Init( void )
{
GLubyte *image;
int imgWidth, imgHeight, minDim, w;
GLenum imgFormat;
if (!glutExtensionSupported("GL_ARB_texture_non_power_of_two")) {
printf("Sorry, this program requires GL_ARB_texture_non_power_of_two\n");
exit(1);
}
#if 1
image = LoadRGBImage( IMAGE_FILE, &imgWidth, &imgHeight, &imgFormat );
if (!image) {
printf("Couldn't read %s\n", IMAGE_FILE);
exit(0);
}
#else
int i, j;
imgFormat = GL_RGB;
imgWidth = 3;
imgHeight = 3;
image = malloc(imgWidth * imgHeight * 3);
for (i = 0; i < imgHeight; i++) {
for (j = 0; j < imgWidth; j++) {
int k = (i * imgWidth + j) * 3;
if ((i + j) & 1) {
image[k+0] = 255;
image[k+1] = 0;
image[k+2] = 0;
}
else {
image[k+0] = 0;
image[k+1] = 255;
image[k+2] = 0;
}
}
}
#endif
printf("Read %d x %d\n", imgWidth, imgHeight);
minDim = imgWidth < imgHeight ? imgWidth : imgHeight;
glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
/*
* 1D Texture. Test proxy first, if that works, test non-proxy target.
*/
glTexImage1D(GL_PROXY_TEXTURE_1D, 0, GL_RGB, imgWidth, 0,
imgFormat, GL_UNSIGNED_BYTE, image);
glGetTexLevelParameteriv(GL_PROXY_TEXTURE_1D, 0, GL_TEXTURE_WIDTH, &w);
assert(w == imgWidth || w == 0);
if (w) {
glTexImage1D(GL_TEXTURE_1D, 0, GL_RGB, imgWidth, 0,
imgFormat, GL_UNSIGNED_BYTE, image);
assert(glGetError() == GL_NO_ERROR);
}
/*
* 2D Texture
*/
glTexImage2D(GL_PROXY_TEXTURE_2D, 0, GL_RGB, imgWidth, imgHeight, 0,
imgFormat, GL_UNSIGNED_BYTE, image);
glGetTexLevelParameteriv(GL_PROXY_TEXTURE_2D, 0, GL_TEXTURE_WIDTH, &w);
assert(w == imgWidth || w == 0);
if (w) {
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, imgWidth, imgHeight, 0,
imgFormat, GL_UNSIGNED_BYTE, image);
assert(glGetError() == GL_NO_ERROR);
}
/*
* 3D Texture
*/
glTexImage3D(GL_PROXY_TEXTURE_3D, 0, GL_RGB, imgWidth, imgHeight, 1, 0,
imgFormat, GL_UNSIGNED_BYTE, image);
glGetTexLevelParameteriv(GL_PROXY_TEXTURE_3D, 0, GL_TEXTURE_WIDTH, &w);
assert(w == imgWidth || w == 0);
if (w) {
glTexImage3D(GL_TEXTURE_3D, 0, GL_RGB, imgWidth, imgHeight, 1, 0,
imgFormat, GL_UNSIGNED_BYTE, image);
assert(glGetError() == GL_NO_ERROR);
}
/*
* Cube Texture
*/
glTexImage2D(GL_PROXY_TEXTURE_CUBE_MAP, 0, GL_RGB,
minDim, minDim, 0,
imgFormat, GL_UNSIGNED_BYTE, image);
glGetTexLevelParameteriv(GL_PROXY_TEXTURE_CUBE_MAP, 0, GL_TEXTURE_WIDTH, &w);
assert(w == minDim || w == 0);
if (w) {
glTexImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X, 0, GL_RGB,
minDim, minDim, 0,
imgFormat, GL_UNSIGNED_BYTE, image);
assert(glGetError() == GL_NO_ERROR);
}
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glEnable(GL_TEXTURE_2D);
}
int main( int argc, char *argv[] )
{
glutInit( &argc, argv );
glutInitWindowPosition( 0, 0 );
glutInitWindowSize( 400, 400 );
glutInitDisplayMode( GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH );
glutCreateWindow(argv[0]);
glewInit();
glutReshapeFunc( Reshape );
glutKeyboardFunc( Key );
glutDisplayFunc( Display );
Init();
glutMainLoop();
return 0;
}
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