--- /dev/null
+/*
+ * Exercise the EXT_422_pixels extension, a less convenient
+ * alternative to MESA_ycbcr_texture. Requires ARB_fragment_program
+ * to perform the final YUV->RGB conversion.
+ *
+ * Brian Paul 13 September 2002
+ * Keith Whitwell 30 November 2004
+ */
+
+
+#include <math.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#define GL_GLEXT_PROTOTYPES
+#include <GL/glut.h>
+#include <assert.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 const GLuint yuvObj = 100;
+
+static void Init( int argc, char *argv[] );
+
+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 )
+{
+ static int firsttime = 1;
+
+ if (firsttime) {
+ firsttime = 0;
+ Init( 0, 0 ); /* don't ask */
+ }
+
+ glClear( GL_COLOR_BUFFER_BIT );
+ glBindTexture(GL_TEXTURE_2D, yuvObj);
+
+ glPushMatrix();
+ glEnable(GL_FRAGMENT_PROGRAM_ARB);
+ 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);
+ DrawObject();
+ glPopMatrix();
+
+ glPushMatrix();
+ glDisable(GL_FRAGMENT_PROGRAM_ARB);
+ 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);
+ 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 LINEAR_FILTER */
+
+static void Init( int argc, char *argv[] )
+{
+ const char *file;
+
+ if (!glutExtensionSupported("GL_ARB_fragment_program")) {
+ printf("Error: GL_ARB_fragment_program not supported!\n");
+ exit(1);
+ }
+
+ if (!glutExtensionSupported("GL_EXT_422_pixels")) {
+ printf("Error: GL_EXT_422_pixels not supported!\n");
+ exit(1);
+ }
+
+ glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
+
+ file = TEXTURE_FILE;
+
+ /* 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);
+ }
+
+ glTexImage2D(GL_TEXTURE_2D, 0,
+ GL_RGB,
+ ImgWidth, ImgHeight, 0,
+ GL_422_EXT,
+ GL_UNSIGNED_BYTE, ImageYUV);
+
+ glEnable(GL_TEXTURE_2D);
+
+ glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);
+
+ {
+ static const char *modulateYUV =
+ "!!ARBfp1.0\n"
+ "TEMP R0;\n"
+ "TEX R0, fragment.texcoord[0], texture[0], 2D; \n"
+
+ "ADD R0, R0, {-0.0625, -0.5, -0.5, 0.0}; \n"
+ "DP3 result.color.x, R0, {1.164, 1.596, 0.0}; \n"
+ "DP3 result.color.y, R0, {1.164, -0.813, -0.391}; \n"
+ "DP3 result.color.z, R0, {1.164, 0.0, 2.018}; \n"
+ "MOV result.color.w, R0.w; \n"
+
+ "END"
+ ;
+
+ GLuint modulateProg;
+
+
+ /* Setup the fragment program */
+ glGenProgramsARB(1, &modulateProg);
+ glBindProgramARB(GL_FRAGMENT_PROGRAM_ARB, modulateProg);
+ glProgramStringARB(GL_FRAGMENT_PROGRAM_ARB, GL_PROGRAM_FORMAT_ASCII_ARB,
+ strlen(modulateYUV), (const GLubyte *)modulateYUV);
+
+ printf("glGetError = 0x%x\n", (int) glGetError());
+ printf("glError(GL_PROGRAM_ERROR_STRING_ARB) = %s\n",
+ (char *) glGetString(GL_PROGRAM_ERROR_STRING_ARB));
+ assert(glIsProgramARB(modulateProg));
+
+ }
+
+ glShadeModel(GL_FLAT);
+ glClearColor(0.3, 0.3, 0.4, 1.0);
+}
+
+
+int main( int argc, char *argv[] )
+{
+ glutInit( &argc, argv );
+ glutInitWindowSize( 300, 300 );
+ glutInitWindowPosition( 0, 0 );
+ glutInitDisplayMode( GLUT_RGB | GLUT_DOUBLE );
+ glutCreateWindow(argv[0] );
+ glutReshapeFunc( Reshape );
+ glutKeyboardFunc( Key );
+ glutSpecialFunc( SpecialKey );
+ glutDisplayFunc( Display );
+ glutMainLoop();
+ return 0;
+}