/*   texture.c   */

/*
     Purpose: demonstrate a simple texture
*/


#ifdef __APPLE__
#include <GLUT/glut.h>
#else
#include <GL/glut.h>
#endif

#include <stdlib.h>


/* Module constants */

/* The image for the texture */
static const GLubyte mpImage[] = {
0x00, 0xff, 0x00, 0xff,  0xff, 0xff, 0xff, 0xff,  0xff, 0xff, 0xff, 0xff,  0xff, 0xff, 0xff, 0xff,
0xff, 0x00, 0x00, 0x00,  0xff, 0x00, 0x00, 0x00,  0xff, 0x00, 0x00, 0x00,  0x00, 0x00, 0x00, 0x00,
0xff, 0x00, 0x00, 0x00,  0xff, 0x00, 0x00, 0x00,  0x00, 0x00, 0x00, 0x00,  0x00, 0x00, 0x00, 0x00,
0xff, 0x00, 0x00, 0x00,  0x00, 0x00, 0x00, 0x00,  0x00, 0x00, 0x00, 0x00,  0x00, 0x00, 0x00, 0x00,
};


/* Functions */

GLvoid display( GLvoid )
{
	glClear( GL_COLOR_BUFFER_BIT );

	/* Note that we are still bound to texture object 0 */
	glBegin( GL_QUADS );
	{
		/* A square with texture coords */
		glTexCoord2f( 0.0, 0.0 ); glVertex2f( -0.5, -0.5 );
		glTexCoord2f( 1.0, 0.0 ); glVertex2f( 0.5, -0.5 );
		glTexCoord2f( 1.0, 1.0 ); glVertex2f( 0.5, 0.5 );
		glTexCoord2f( 0.0, 1.0 ); glVertex2f( -0.5, 0.5 );		
	}
	glEnd();

	glFlush();
}


void init( void )
{	
	/* Put the image into the texture object */					
	glTexImage2D( GL_TEXTURE_2D, 0, GL_RGBA, 4, 4, 0, GL_RGBA, GL_UNSIGNED_BYTE, mpImage );
	
	/* Specify the magnification/minification method */
	glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST );
	glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST );	
	
	/* Replace the current polygon colours with the texture */
	glTexEnvf( GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE );
	
	/* Enable texturing */
	glEnable( GL_TEXTURE_2D );		
}


int main( int argc, char *argv[] )
{

	glutInit( &argc, argv );
	glutCreateWindow( argv[0] );

	glutDisplayFunc( display ); 
	init();
	
	glutMainLoop();
	
	return 0;
}