--- /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;
+}
projects / platform / upstream / mesa.git / commitdiff