+++ /dev/null
-/* $Id: anisotropic.c,v 1.1 2001/03/22 15:24:15 gareth Exp $ */
-
-/*
- * GL_ARB_texture_filter_anisotropic demo
- *
- * Gareth Hughes
- * March 2001
- *
- * Copyright (C) 2000 Brian Paul All Rights Reserved.
- *
- * Permission is hereby granted, free of charge, to any person obtaining a
- * copy of this software and associated documentation files (the "Software"),
- * to deal in the Software without restriction, including without limitation
- * the rights to use, copy, modify, merge, publish, distribute, sublicense,
- * and/or sell copies of the Software, and to permit persons to whom the
- * Software is furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included
- * in all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
- * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
- * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
- * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
- * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
- */
-
-/* This is a fairly early version. All it does is draw a couple of
- * textured quads with different forms of texture filtering. Eventually,
- * you'll be able to adjust the maximum anisotropy and so on.
- */
-
-#include <math.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <GL/glut.h>
-
-#define TEXTURE_SIZE 256
-static GLubyte image[TEXTURE_SIZE][TEXTURE_SIZE][3];
-
-static GLfloat repeat = 1.0;
-
-static GLfloat texcoords[] = {
- 0.0, 0.0,
- 0.0, 1.0,
- 1.0, 0.0,
- 1.0, 1.0
-};
-
-static GLfloat vertices[] = {
- -400.0, -400.0, 0.0,
- -400.0, 400.0, -7000.0,
- 400.0, -400.0, 0.0,
- 400.0, 400.0, -7000.0
-};
-
-static GLfloat maxAnisotropy;
-
-
-static void init( void )
-{
- int i, j;
-
- if ( !glutExtensionSupported( "GL_EXT_texture_filter_anisotropic" ) ) {
- fprintf( stderr, "Sorry, this demo requires GL_EXT_texture_filter_anisotropic.\n" );
- exit( 0 );
- }
-
- glClearColor( 0.0, 0.0, 0.0, 0.0 );
- glShadeModel( GL_SMOOTH );
-
- /* Init the vertex arrays.
- */
- glEnableClientState( GL_VERTEX_ARRAY );
- glEnableClientState( GL_TEXTURE_COORD_ARRAY );
-
- glVertexPointer( 3, GL_FLOAT, 0, vertices );
- glTexCoordPointer( 2, GL_FLOAT, 0, texcoords );
-
- /* Init the texture environment.
- */
- glEnable( GL_TEXTURE_2D );
- glTexEnvi( GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE );
-
- glMatrixMode( GL_TEXTURE );
- glScalef( repeat, repeat, 0 );
-
- glMatrixMode( GL_MODELVIEW );
-
- glGetFloatv( GL_MAX_TEXTURE_MAX_ANISOTROPY_EXT, &maxAnisotropy );
- printf( "Maximum supported anisotropy: %.2f\n", maxAnisotropy );
-
- /* Make the texture image.
- */
- glPixelStorei( GL_UNPACK_ALIGNMENT, 1 );
-
- for ( i = 0 ; i < TEXTURE_SIZE ; i++ ) {
- for ( j = 0 ; j < TEXTURE_SIZE ; j++ ) {
- if ( (i/4 + j/4) & 1 ) {
- image[i][j][0] = 0;
- image[i][j][1] = 0;
- image[i][j][2] = 0;
- } else {
- image[i][j][0] = 255;
- image[i][j][1] = 255;
- image[i][j][2] = 255;
- }
- }
- }
-
- gluBuild2DMipmaps( GL_TEXTURE_2D, GL_RGB, TEXTURE_SIZE, TEXTURE_SIZE,
- GL_RGB, GL_UNSIGNED_BYTE, image );
-}
-
-static void display( void )
-{
- GLint vp[4], w, h;
-
- glClear( GL_COLOR_BUFFER_BIT );
-
- glGetIntegerv( GL_VIEWPORT, vp );
- w = vp[2] / 2;
- h = vp[3] / 2;
-
- /* Upper left corner:
- */
- glViewport( 1, h + 1, w - 2, h - 2 );
-
- glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
- glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_MAX_ANISOTROPY_EXT, maxAnisotropy );
-
- glDrawArrays( GL_TRIANGLE_STRIP, 0, 4 );
-
-
- /* Upper right corner:
- */
- glViewport( w + 1, h + 1, w - 2, h - 2 );
-
- glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_NEAREST );
- glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_MAX_ANISOTROPY_EXT, maxAnisotropy );
-
- glDrawArrays( GL_TRIANGLE_STRIP, 0, 4 );
-
-
- /* Lower left corner:
- */
- glViewport( 1, 1, w - 2, h - 2 );
-
- glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST_MIPMAP_LINEAR );
- glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_MAX_ANISOTROPY_EXT, maxAnisotropy );
-
- glDrawArrays( GL_TRIANGLE_STRIP, 0, 4 );
-
-
- /* Lower right corner:
- */
- glViewport( w + 1, 1, w - 2, h - 2 );
-
- glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR );
- glTexParameterf( GL_TEXTURE_2D, GL_TEXTURE_MAX_ANISOTROPY_EXT, maxAnisotropy );
-
- glDrawArrays( GL_TRIANGLE_STRIP, 0, 4 );
-
-
- glViewport( vp[0], vp[1], vp[2], vp[3] );
-
- glutSwapBuffers();
-}
-
-static void reshape( int w, int h )
-{
- glViewport( 0, 0, (GLsizei) w, (GLsizei) h );
-
- glMatrixMode( GL_PROJECTION );
- glLoadIdentity();
- glFrustum( -1.0, 1.0, -1.0, 1.0, 10.0, 10000.0 );
-
- glMatrixMode( GL_MODELVIEW );
- glLoadIdentity();
- glTranslatef( 0.0, 0.0, -10.0 );
-}
-
-static void key( unsigned char key, int x, int y )
-{
- (void) x; (void) y;
-
- switch ( key ) {
- case 27:
- exit( 0 );
- }
-
- glutPostRedisplay();
-}
-
-static void usage( void )
-{
- /* Nothing yet... */
-}
-
-int main( int argc, char **argv )
-{
- glutInit( &argc, argv );
- glutInitDisplayMode( GLUT_DOUBLE | GLUT_RGB );
- glutInitWindowSize( 600, 300 );
- glutInitWindowPosition( 0, 0 );
- glutCreateWindow( "Anisotropic Texture Filter Demo" );
-
- init();
-
- glutDisplayFunc( display );
- glutReshapeFunc( reshape );
- glutKeyboardFunc( key );
-
- usage();
-
- glutMainLoop();
-
- return 0;
-}