| 123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174 | /*
 * 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/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);
   glTexImage1D(GL_TEXTURE_1D, 0, GL_RGB, imgWidth, 0,
                imgFormat, GL_UNSIGNED_BYTE, image);
   assert(glGetError() == GL_NO_ERROR);
   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);
   glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, imgWidth, imgHeight, 0,
                imgFormat, GL_UNSIGNED_BYTE, image);
   assert(glGetError() == GL_NO_ERROR);
   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);
   glTexImage3D(GL_TEXTURE_3D, 0, GL_RGB, imgWidth, imgHeight, 1, 0,
                imgFormat, GL_UNSIGNED_BYTE, image);
   assert(glGetError() == GL_NO_ERROR);
   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);
   glTexImage2D(GL_TEXTURE_CUBE_MAP_POSITIVE_X, 0, GL_RGB,
                minDim, minDim, 0,
                imgFormat, GL_UNSIGNED_BYTE, image);
   assert(glGetError() == GL_NO_ERROR);
   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);
   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]);
   glutReshapeFunc( Reshape );
   glutKeyboardFunc( Key );
   glutDisplayFunc( Display );
   Init();
   glutMainLoop();
   return 0;
}
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