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/*
* Test the GL_NV_texture_rectangle and GL_MESA_ycrcb_texture extensions.
*
* Brian Paul 13 September 2002
*/
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define GL_GLEXT_PROTOTYPES
#include <GL/glut.h>
#include "../util/readtex.c" /* I know, this is a hack. */
#define TEXTURE_FILE "../images/tile.rgb"
static GLfloat Xrot = 0, Yrot = 0, Zrot = 0;
static GLint ImgWidth, ImgHeight;
static GLushort *ImageYUV = NULL;
static GLubyte *ImageRGB = NULL;
static const GLuint yuvObj = 100;
static const GLuint rgbObj = 101;
static void DrawObject(void)
{
glBegin(GL_QUADS);
glTexCoord2f(0, 0);
glVertex2f(-1.0, -1.0);
glTexCoord2f(1, 0);
glVertex2f(1.0, -1.0);
glTexCoord2f(1, 1);
glVertex2f(1.0, 1.0);
glTexCoord2f(0, 1);
glVertex2f(-1.0, 1.0);
glEnd();
}
static void Display( void )
{
glClear( GL_COLOR_BUFFER_BIT );
glPushMatrix();
glTranslatef( -1.1, 0.0, -15.0 );
glRotatef(Xrot, 1.0, 0.0, 0.0);
glRotatef(Yrot, 0.0, 1.0, 0.0);
glRotatef(Zrot, 0.0, 0.0, 1.0);
glBindTexture(GL_TEXTURE_2D, yuvObj);
DrawObject();
glPopMatrix();
glPushMatrix();
glTranslatef( 1.1, 0.0, -15.0 );
glRotatef(Xrot, 1.0, 0.0, 0.0);
glRotatef(Yrot, 0.0, 1.0, 0.0);
glRotatef(Zrot, 0.0, 0.0, 1.0);
glBindTexture(GL_TEXTURE_2D, rgbObj);
DrawObject();
glPopMatrix();
glutSwapBuffers();
}
static void Reshape( int width, int height )
{
glViewport( 0, 0, width, height );
glMatrixMode( GL_PROJECTION );
glLoadIdentity();
glFrustum( -1.1, 1.1, -1.1, 1.1, 10.0, 100.0 );
glMatrixMode( GL_MODELVIEW );
glLoadIdentity();
glTranslatef( 0.0, 0.0, -15.0 );
}
static void Key( unsigned char key, int x, int y )
{
(void) x;
(void) y;
switch (key) {
case 27:
exit(0);
break;
}
glutPostRedisplay();
}
static void SpecialKey( int key, int x, int y )
{
float step = 3.0;
(void) x;
(void) y;
switch (key) {
case GLUT_KEY_UP:
Xrot += step;
break;
case GLUT_KEY_DOWN:
Xrot -= step;
break;
case GLUT_KEY_LEFT:
Yrot += step;
break;
case GLUT_KEY_RIGHT:
Yrot -= step;
break;
}
glutPostRedisplay();
}
#define CLAMP( X, MIN, MAX ) ( (X)<(MIN) ? (MIN) : ((X)>(MAX) ? (MAX) : (X)) )
/* #define LINEAR_FILTER */
static void Init( int argc, char *argv[] )
{
const char *file;
int error;
GLenum format;
if (!glutExtensionSupported("GL_MESA_ycbcr_texture")) {
printf("Sorry, GL_MESA_ycbcr_texture is required\n");
exit(0);
}
glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
if (argc > 1)
file = argv[1];
else
file = TEXTURE_FILE;
/* First load the texture as YCbCr.
*/
glBindTexture(GL_TEXTURE_2D, yuvObj);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
ImageYUV = LoadYUVImage(file, &ImgWidth, &ImgHeight );
if (!ImageYUV) {
printf("Couldn't read %s\n", TEXTURE_FILE);
exit(0);
}
printf("Image: %dx%d\n", ImgWidth, ImgHeight);
glTexImage2D(GL_TEXTURE_2D, 0,
GL_YCBCR_MESA,
ImgWidth, ImgHeight, 0,
GL_YCBCR_MESA,
GL_UNSIGNED_SHORT_8_8_MESA, ImageYUV);
glEnable(GL_TEXTURE_2D);
glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
/* Now load the texture as RGB.
*/
glBindTexture(GL_TEXTURE_2D, rgbObj);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
ImageRGB = LoadRGBImage(file, &ImgWidth, &ImgHeight, &format );
if (!ImageRGB) {
printf("Couldn't read %s\n", TEXTURE_FILE);
exit(0);
}
printf("Image: %dx%d\n", ImgWidth, ImgHeight);
glTexImage2D(GL_TEXTURE_2D, 0,
format,
ImgWidth, ImgHeight, 0,
format,
GL_UNSIGNED_BYTE, ImageRGB);
glEnable(GL_TEXTURE_2D);
glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
glShadeModel(GL_FLAT);
glClearColor(0.3, 0.3, 0.4, 1.0);
if (argc > 1 && strcmp(argv[1], "-info")==0) {
printf("GL_RENDERER = %s\n", (char *) glGetString(GL_RENDERER));
printf("GL_VERSION = %s\n", (char *) glGetString(GL_VERSION));
printf("GL_VENDOR = %s\n", (char *) glGetString(GL_VENDOR));
printf("GL_EXTENSIONS = %s\n", (char *) glGetString(GL_EXTENSIONS));
}
printf( "Both images should appear the same.\n" );
}
int main( int argc, char *argv[] )
{
glutInit( &argc, argv );
glutInitWindowSize( 300, 300 );
glutInitWindowPosition( 0, 0 );
glutInitDisplayMode( GLUT_RGB | GLUT_DOUBLE );
glutCreateWindow(argv[0] );
Init( argc, argv );
glutReshapeFunc( Reshape );
glutKeyboardFunc( Key );
glutSpecialFunc( SpecialKey );
glutDisplayFunc( Display );
glutMainLoop();
return 0;
}
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