xenocara/dist/Mesa/progs/demos/texenv.c

818 lines
22 KiB
C

/* Copyright (c) Mark J. Kilgard, 1994. */
/**
* (c) Copyright 1993, Silicon Graphics, Inc.
* ALL RIGHTS RESERVED
* Permission to use, copy, modify, and distribute this software for
* any purpose and without fee is hereby granted, provided that the above
* copyright notice appear in all copies and that both the copyright notice
* and this permission notice appear in supporting documentation, and that
* the name of Silicon Graphics, Inc. not be used in advertising
* or publicity pertaining to distribution of the software without specific,
* written prior permission.
*
* THE MATERIAL EMBODIED ON THIS SOFTWARE IS PROVIDED TO YOU "AS-IS"
* AND WITHOUT WARRANTY OF ANY KIND, EXPRESS, IMPLIED OR OTHERWISE,
* INCLUDING WITHOUT LIMITATION, ANY WARRANTY OF MERCHANTABILITY OR
* FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL SILICON
* GRAPHICS, INC. BE LIABLE TO YOU OR ANYONE ELSE FOR ANY DIRECT,
* SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY
* KIND, OR ANY DAMAGES WHATSOEVER, INCLUDING WITHOUT LIMITATION,
* LOSS OF PROFIT, LOSS OF USE, SAVINGS OR REVENUE, OR THE CLAIMS OF
* THIRD PARTIES, WHETHER OR NOT SILICON GRAPHICS, INC. HAS BEEN
* ADVISED OF THE POSSIBILITY OF SUCH LOSS, HOWEVER CAUSED AND ON
* ANY THEORY OF LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE
* POSSESSION, USE OR PERFORMANCE OF THIS SOFTWARE.
*
* US Government Users Restricted Rights
* Use, duplication, or disclosure by the Government is subject to
* restrictions set forth in FAR 52.227.19(c)(2) or subparagraph
* (c)(1)(ii) of the Rights in Technical Data and Computer Software
* clause at DFARS 252.227-7013 and/or in similar or successor
* clauses in the FAR or the DOD or NASA FAR Supplement.
* Unpublished-- rights reserved under the copyright laws of the
* United States. Contractor/manufacturer is Silicon Graphics,
* Inc., 2011 N. Shoreline Blvd., Mountain View, CA 94039-7311.
*
* OpenGL(TM) is a trademark of Silicon Graphics, Inc.
*/
/*
* Demonstrates texture environment modes and internal image formats.
*/
/*
* Hacked on, updated by Gareth Hughes <gareth@valinux.com>
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <GL/glut.h>
#undef max
#undef min
#define max( a, b ) ((a) >= (b) ? (a) : (b))
#define min( a, b ) ((a) <= (b) ? (a) : (b))
GLfloat lightCheck[4] = { 0.7, 0.7, 0.7, 1.0 };
GLfloat darkCheck[4] = { 0.3, 0.3, 0.3, 1.0 };
GLfloat labelColor0[4] = { 1.0, 1.0, 1.0, 1.0 };
GLfloat labelColor1[4] = { 1.0, 1.0, 0.4, 1.0 };
GLfloat *labelInfoColor = labelColor0;
GLfloat labelLevelColor0[4] = { 0.8, 0.8, 0.1, 1.0 };
GLfloat labelLevelColor1[4] = { 0.0, 0.0, 0.0, 1.0 };
GLboolean doubleBuffered = GL_TRUE;
GLboolean drawBackground = GL_FALSE;
GLboolean drawBlended = GL_TRUE;
GLboolean drawSmooth = GL_FALSE;
GLboolean drawTextured = GL_TRUE;
GLboolean displayLevelInfo = GL_FALSE;
int textureWidth = 64;
int textureHeight = 64;
int winWidth = 580, winHeight = 720;
static int Win;
struct formatInfo {
GLenum baseFormat;
GLenum internalFormat;
char *name;
};
#define NUM_LUMINANCE_FORMATS (sizeof(luminanceFormats) / sizeof(luminanceFormats[0]))
struct formatInfo luminanceFormats[] =
{
{ GL_LUMINANCE, GL_LUMINANCE, "LUMINANCE" },
{ GL_LUMINANCE, GL_LUMINANCE4, "LUMINANCE4" },
{ GL_LUMINANCE, GL_LUMINANCE8, "LUMINANCE8" },
{ GL_LUMINANCE, GL_LUMINANCE12, "LUMINANCE12" },
{ GL_LUMINANCE, GL_LUMINANCE16, "LUMINANCE16" },
};
#define NUM_ALPHA_FORMATS (sizeof(alphaFormats) / sizeof(alphaFormats[0]))
struct formatInfo alphaFormats[] =
{
{ GL_ALPHA, GL_ALPHA, "ALPHA" },
{ GL_ALPHA, GL_ALPHA4, "ALPHA4" },
{ GL_ALPHA, GL_ALPHA8, "ALPHA8" },
{ GL_ALPHA, GL_ALPHA12, "ALPHA12" },
{ GL_ALPHA, GL_ALPHA16, "ALPHA16" },
};
#define NUM_INTENSITY_FORMATS (sizeof(intensityFormats) / sizeof(intensityFormats[0]))
struct formatInfo intensityFormats[] =
{
{ GL_INTENSITY, GL_INTENSITY, "INTENSITY" },
{ GL_INTENSITY, GL_INTENSITY4, "INTENSITY4" },
{ GL_INTENSITY, GL_INTENSITY8, "INTENSITY8" },
{ GL_INTENSITY, GL_INTENSITY12, "INTENSITY12" },
{ GL_INTENSITY, GL_INTENSITY16, "INTENSITY16" },
};
#define NUM_LUMINANCE_ALPHA_FORMATS (sizeof(luminanceAlphaFormats) / sizeof(luminanceAlphaFormats[0]))
struct formatInfo luminanceAlphaFormats[] =
{
{ GL_LUMINANCE_ALPHA, GL_LUMINANCE_ALPHA, "LUMINANCE_ALPHA" },
{ GL_LUMINANCE_ALPHA, GL_LUMINANCE4_ALPHA4, "LUMINANCE4_ALPHA4" },
{ GL_LUMINANCE_ALPHA, GL_LUMINANCE6_ALPHA2, "LUMINANCE6_ALPHA2" },
{ GL_LUMINANCE_ALPHA, GL_LUMINANCE8_ALPHA8, "LUMINANCE8_ALPHA8" },
{ GL_LUMINANCE_ALPHA, GL_LUMINANCE12_ALPHA4, "LUMINANCE12_ALPHA4" },
{ GL_LUMINANCE_ALPHA, GL_LUMINANCE12_ALPHA12, "LUMINANCE12_ALPHA12" },
{ GL_LUMINANCE_ALPHA, GL_LUMINANCE16_ALPHA16, "LUMINANCE16_ALPHA16" },
};
#define NUM_RGB_FORMATS (sizeof(rgbFormats) / sizeof(rgbFormats[0]))
struct formatInfo rgbFormats[] =
{
{ GL_RGB, GL_RGB, "RGB" },
{ GL_RGB, GL_R3_G3_B2, "R3_G3_B2" },
{ GL_RGB, GL_RGB4, "RGB4" },
{ GL_RGB, GL_RGB5, "RGB5" },
{ GL_RGB, GL_RGB8, "RGB8" },
{ GL_RGB, GL_RGB10, "RGB10" },
{ GL_RGB, GL_RGB12, "RGB12" },
{ GL_RGB, GL_RGB16, "RGB16" },
};
#define NUM_RGBA_FORMATS (sizeof(rgbaFormats) / sizeof(rgbaFormats[0]))
struct formatInfo rgbaFormats[] =
{
{ GL_RGBA, GL_RGBA, "RGBA" },
{ GL_RGBA, GL_RGBA2, "RGBA2" },
{ GL_RGBA, GL_RGBA4, "RGBA4" },
{ GL_RGBA, GL_RGB5_A1, "RGB5_A1" },
{ GL_RGBA, GL_RGBA8, "RGBA8" },
{ GL_RGBA, GL_RGB10_A2, "RGB10_A2" },
{ GL_RGBA, GL_RGBA12, "RGBA12" },
{ GL_RGBA, GL_RGBA16, "RGBA16" },
};
struct baseFormatInfo {
struct formatInfo *format;
int current, number;
};
#define NUM_BASE_FORMATS (sizeof(baseFormats) / sizeof(baseFormats[0]))
int baseFormat;
struct baseFormatInfo baseFormats[] =
{
{ luminanceFormats, 0, NUM_LUMINANCE_FORMATS },
{ alphaFormats, 0, NUM_ALPHA_FORMATS },
{ intensityFormats, 0, NUM_INTENSITY_FORMATS },
{ luminanceAlphaFormats, 0, NUM_LUMINANCE_ALPHA_FORMATS },
{ rgbFormats, 0, NUM_RGB_FORMATS },
{ rgbaFormats, 0, NUM_RGBA_FORMATS },
};
#define NUM_ENV_COLORS (sizeof(envColors) / sizeof(envColors[0]))
int envColor = 0;
GLfloat envColors[][4] =
{
{ 0.0, 0.0, 0.0, 1.0 },
{ 1.0, 0.0, 0.0, 1.0 },
{ 0.0, 1.0, 0.0, 1.0 },
{ 0.0, 0.0, 1.0, 1.0 },
{ 1.0, 1.0, 1.0, 1.0 },
};
struct envModeInfo {
GLenum mode;
char *name;
};
/* allow for run-time check for GL_EXT_texture_env_add */
int NUM_ENV_MODES = 5;
struct envModeInfo envModes[] =
{
{ GL_REPLACE, "REPLACE" },
{ GL_MODULATE, "MODULATE" },
{ GL_BLEND, "BLEND" },
{ GL_DECAL, "DECAL" },
#if GL_EXT_texture_env_add
{ GL_ADD, "ADD" },
#endif
};
static void checkErrors( void )
{
GLenum error;
while ( (error = glGetError()) != GL_NO_ERROR ) {
fprintf( stderr, "Error: %s\n", (char *) gluErrorString( error ) );
}
}
static void drawString( const char *string, GLfloat x, GLfloat y,
const GLfloat color[4] )
{
glColor4fv( color );
glRasterPos2f( x, y );
while ( *string ) {
glutBitmapCharacter( GLUT_BITMAP_TIMES_ROMAN_10, *string );
string++;
}
}
static void drawStringOutline( const char *string, GLfloat x, GLfloat y,
const GLfloat color[4],
const GLfloat outline[4] )
{
drawString( string, x - 1, y, outline );
drawString( string, x + 1, y, outline );
drawString( string, x, y - 1, outline );
drawString( string, x, y + 1, outline );
drawString( string, x, y, color );
}
static void begin2D( int width, int height )
{
glMatrixMode( GL_PROJECTION );
glPushMatrix();
glLoadIdentity();
glOrtho( 0, width, 0, height, -1, 1 );
glMatrixMode( GL_MODELVIEW );
glPushMatrix();
glLoadIdentity();
}
static void end2D( void )
{
glMatrixMode( GL_PROJECTION );
glPopMatrix();
glMatrixMode( GL_MODELVIEW );
glPopMatrix();
}
static void initialize( void )
{
glMatrixMode( GL_PROJECTION );
glLoadIdentity();
glOrtho( -1.5, 1.5, -1.5, 1.5, -1.5, 1.5 );
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glShadeModel( GL_FLAT );
}
/* ARGSUSED1 */
static void keyboard( unsigned char c, int x, int y )
{
switch ( c ) {
case 'c':
envColor++;
envColor = envColor % (int) NUM_ENV_COLORS;
break;
case 'g':
drawBackground = !drawBackground;
break;
case 'b':
drawBlended = !drawBlended;
break;
case 's':
drawSmooth = !drawSmooth;
break;
case 't':
drawTextured = !drawTextured;
break;
case 'i':
displayLevelInfo = !displayLevelInfo;
break;
case 27: /* Escape key should force exit. */
glutDestroyWindow(Win);
exit(0);
break;
default:
break;
}
glutPostRedisplay();
}
/* ARGSUSED1 */
static void special( int key, int x, int y )
{
switch ( key ) {
case GLUT_KEY_DOWN:
if ( ++baseFormat > NUM_BASE_FORMATS - 1 ) {
baseFormat = 0;
}
break;
case GLUT_KEY_UP:
if ( --baseFormat < 0 ) {
baseFormat = NUM_BASE_FORMATS - 1;
}
break;
case GLUT_KEY_LEFT:
--baseFormats[baseFormat].current;
if ( baseFormats[baseFormat].current < 0 ) {
baseFormats[baseFormat].current = baseFormats[baseFormat].number - 1;
}
break;
case GLUT_KEY_RIGHT:
++baseFormats[baseFormat].current;
if ( baseFormats[baseFormat].current > baseFormats[baseFormat].number - 1 ) {
baseFormats[baseFormat].current = 0;
}
break;
default:
break;
}
glutPostRedisplay();
}
static void
reshape( int w, int h )
{
winWidth = w;
winHeight = h;
/* No need to call glViewPort here since "draw" calls it! */
}
static void loadTexture( int width, int height,
const struct formatInfo *format )
{
int luminanceSize = 0;
int alphaSize = 0;
int rgbSize = 0;
GLenum textureFormat;
GLubyte *texImage, *p;
int elementsPerGroup, elementSize, groupSize, rowSize;
int i, j;
switch ( format->baseFormat ) {
case GL_LUMINANCE:
luminanceSize = 1;
textureFormat = GL_LUMINANCE;
break;
case GL_INTENSITY:
luminanceSize = 1;
/* Note: format=GL_INTENSITY for glTexImage is not legal */
textureFormat = GL_LUMINANCE;
break;
case GL_ALPHA:
alphaSize = 1;
textureFormat = GL_ALPHA;
break;
case GL_LUMINANCE_ALPHA:
luminanceSize = 1;
alphaSize = 1;
textureFormat = GL_LUMINANCE_ALPHA;
break;
case GL_RGB:
rgbSize = 3;
textureFormat = GL_RGB;
break;
case GL_RGBA:
rgbSize = 3;
alphaSize = 1;
textureFormat = GL_RGBA;
break;
default:
fprintf(stderr, "bad internal format info\n");
return;
}
elementsPerGroup = luminanceSize + alphaSize + rgbSize;
elementSize = sizeof(GLubyte);
groupSize = elementsPerGroup * elementSize;
rowSize = width * groupSize;
if ( (texImage = (GLubyte *) malloc( height * rowSize ) ) == NULL ) {
fprintf( stderr, "texture malloc failed\n" );
return;
}
for ( i = 0 ; i < height ; i++ )
{
p = texImage + i * rowSize;
for ( j = 0 ; j < width ; j++ )
{
if ( luminanceSize > 0 )
{
/**
** +-----+-----+
** | | |
** | W | LG |
** | | |
** +-----+-----+
** | | |
** | DG | B |
** | | |
** +-----+-----+
**/
if ( i > height / 2 ) {
if ( j < width / 2 ) {
p[0] = 0xff;
} else {
p[0] = 0xaa;
}
} else {
if ( j < width / 2 ) {
p[0] = 0x55;
} else {
p[0] = 0x00;
}
}
p += elementSize;
}
if ( rgbSize > 0 )
{
/**
** +-----+-----+
** | | |
** | R | G |
** | | |
** +-----+-----+
** | | |
** | Y | B |
** | | |
** +-----+-----+
**/
if ( i > height / 2 ) {
if ( j < width / 2 ) {
p[0] = 0xff;
p[1] = 0x00;
p[2] = 0x00;
} else {
p[0] = 0x00;
p[1] = 0xff;
p[2] = 0x00;
}
} else {
if ( j < width / 2 ) {
p[0] = 0xff;
p[1] = 0xff;
p[2] = 0x00;
} else {
p[0] = 0x00;
p[1] = 0x00;
p[2] = 0xff;
}
}
p += 3 * elementSize;
}
if ( alphaSize > 0 )
{
/**
** +-----------+
** | W |
** | +-----+ |
** | | | |
** | | B | |
** | | | |
** | +-----+ |
** | |
** +-----------+
**/
int i2 = i - height / 2;
int j2 = j - width / 2;
int h8 = height / 8;
int w8 = width / 8;
if ( -h8 <= i2 && i2 <= h8 && -w8 <= j2 && j2 <= w8 ) {
p[0] = 0x00;
} else if ( -2 * h8 <= i2 && i2 <= 2 * h8 && -2 * w8 <= j2 && j2 <= 2 * w8 ) {
p[0] = 0x55;
} else if ( -3 * h8 <= i2 && i2 <= 3 * h8 && -3 * w8 <= j2 && j2 <= 3 * w8 ) {
p[0] = 0xaa;
} else {
p[0] = 0xff;
}
p += elementSize;
}
}
}
glTexImage2D( GL_TEXTURE_2D, 0,
format->internalFormat, width, height, 0,
textureFormat, GL_UNSIGNED_BYTE, texImage );
free( texImage );
}
static void drawCheck( int w, int h, const GLfloat lightCheck[4],
const GLfloat darkCheck[4] )
{
float dw = 2.0 / w;
float dh = 2.0 / h;
int i, j;
for ( i = 0 ; i < w ; i++ ) {
GLfloat x0 = -1.0 + i * dw;
GLfloat x1 = x0 + dw;
glBegin( GL_QUAD_STRIP );
for ( j = 0 ; j <= h ; j++ ) {
GLfloat y = -1.0 + j * dh;
if ( (i ^ j) & 1 ) {
glColor4fv( lightCheck );
} else {
glColor4fv( darkCheck );
}
glVertex2f( x0, y );
glVertex2f( x1, y );
}
glEnd();
}
}
static const char *lookupFormat( GLint format )
{
switch ( format ) {
case GL_RGBA:
return "GL_RGBA";
case GL_RGB:
return "GL_RGB";
case GL_ALPHA:
return "GL_ALPHA";
case GL_LUMINANCE:
return "GL_LUMINANCE";
case GL_LUMINANCE_ALPHA:
return "GL_LUMINANCE_ALPHA";
case GL_INTENSITY:
return "GL_INTENSITY";
case GL_COLOR_INDEX:
return "GL_COLOR_INDEX";
case GL_BGRA:
return "GL_BGRA";
case GL_BGR:
return "GL_BGR";
default:
return "unknown format";
}
}
static void drawSample( int x, int y, int w, int h,
const struct formatInfo *format,
const struct envModeInfo *envMode )
{
glViewport( x, y, w, h );
glScissor( x, y, w, h );
glClearColor( 0.1, 0.1, 0.1, 1.0 );
glClear( GL_COLOR_BUFFER_BIT );
begin2D( w, h );
drawString( format->name, 10, h - 15, labelInfoColor );
drawString( envMode->name, 10, 5, labelInfoColor );
end2D();
glTexEnvi( GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, envMode->mode );
glTexEnvfv( GL_TEXTURE_ENV, GL_TEXTURE_ENV_COLOR, envColors[envColor] );
glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST );
glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST );
glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP );
glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP );
loadTexture( textureWidth, textureHeight, format );
if ( drawBackground ) {
drawCheck( 15, 15, lightCheck, darkCheck );
}
if ( drawBlended ) {
glBlendFunc( GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA );
glEnable( GL_BLEND );
}
if ( drawSmooth ) {
glShadeModel( GL_SMOOTH );
}
else {
glShadeModel( GL_FLAT );
glColor4f(1, 1, 1, 1);
}
if ( drawTextured ) {
glEnable( GL_TEXTURE_2D );
}
/*
* if (drawSmooth) then draw quad which goes from purple at the
* bottom (100% alpha) to green at the top (50% alpha).
*/
glBegin( GL_QUADS );
if ( drawSmooth ) glColor4f( 1.0, 0.0, 1.0, 1.0 );
glTexCoord2f( 0.0, 0.0 );
glVertex2f( -0.8, -0.8 );
if ( drawSmooth ) glColor4f( 1.0, 0.0, 1.0, 1.0 );
glTexCoord2f( 1.0, 0.0 );
glVertex2f( 0.8, -0.8 );
if ( drawSmooth ) glColor4f( 0.0, 1.0, 0.0, 0.5 );
glTexCoord2f( 1.0, 1.0 );
glVertex2f( 0.8, 0.8 );
if ( drawSmooth ) glColor4f( 0.0, 1.0, 0.0, 0.5 );
glTexCoord2f( 0.0, 1.0 );
glVertex2f( -0.8, 0.8 );
glEnd();
glDisable( GL_BLEND );
glShadeModel( GL_FLAT );
glDisable( GL_TEXTURE_2D );
if ( envMode->mode == GL_DECAL &&
(format->baseFormat == GL_ALPHA ||
format->baseFormat == GL_LUMINANCE ||
format->baseFormat == GL_LUMINANCE_ALPHA ||
format->baseFormat == GL_INTENSITY)) {
/* undefined format/mode combination */
begin2D( w, h );
drawStringOutline( "UNDEFINED MODE", 15, h / 2,
labelLevelColor0, labelLevelColor1 );
end2D();
}
else if ( displayLevelInfo ) {
GLint width, height, border, format;
GLint redSize, greenSize, blueSize, alphaSize;
GLint luminanceSize, intensitySize;
char buf[255];
glGetTexLevelParameteriv( GL_TEXTURE_2D, 0, GL_TEXTURE_WIDTH, &width );
glGetTexLevelParameteriv( GL_TEXTURE_2D, 0, GL_TEXTURE_HEIGHT, &height );
glGetTexLevelParameteriv( GL_TEXTURE_2D, 0, GL_TEXTURE_BORDER, &border );
glGetTexLevelParameteriv( GL_TEXTURE_2D, 0, GL_TEXTURE_INTERNAL_FORMAT, &format );
glGetTexLevelParameteriv( GL_TEXTURE_2D, 0, GL_TEXTURE_RED_SIZE, &redSize );
glGetTexLevelParameteriv( GL_TEXTURE_2D, 0, GL_TEXTURE_GREEN_SIZE, &greenSize );
glGetTexLevelParameteriv( GL_TEXTURE_2D, 0, GL_TEXTURE_BLUE_SIZE, &blueSize );
glGetTexLevelParameteriv( GL_TEXTURE_2D, 0, GL_TEXTURE_ALPHA_SIZE, &alphaSize );
glGetTexLevelParameteriv( GL_TEXTURE_2D, 0, GL_TEXTURE_LUMINANCE_SIZE, &luminanceSize );
glGetTexLevelParameteriv( GL_TEXTURE_2D, 0, GL_TEXTURE_INTENSITY_SIZE, &intensitySize );
begin2D( w, h );
sprintf( buf, "dimensions: %d x %d", width, height );
drawStringOutline( buf, 15, h / 2 + 20, labelLevelColor0, labelLevelColor1 );
sprintf( buf, "border: %d", border );
drawStringOutline( buf, 15, h / 2 + 10, labelLevelColor0, labelLevelColor1 );
sprintf( buf, "internal format:" );
drawStringOutline( buf, 15, h / 2, labelLevelColor0, labelLevelColor1 );
sprintf( buf, " %s", lookupFormat( format ) );
drawStringOutline( buf, 15, h / 2 - 10, labelLevelColor0, labelLevelColor1 );
sprintf( buf, "sizes:" );
drawStringOutline( buf, 15, h / 2 - 20, labelLevelColor0, labelLevelColor1 );
sprintf( buf, " %d / %d / %d / %d / %d / %d",
redSize, greenSize, blueSize, alphaSize,
luminanceSize, intensitySize );
drawStringOutline( buf, 15, h / 2 - 30, labelLevelColor0, labelLevelColor1 );
end2D();
}
}
static void display( void )
{
int numX = NUM_ENV_MODES, numY = NUM_BASE_FORMATS;
float xBase = (float) winWidth * 0.01;
float xOffset = (winWidth - xBase) / numX;
float xSize = max( xOffset - xBase, 1 );
float yBase = (float) winHeight * 0.01;
float yOffset = (winHeight - yBase) / numY;
float ySize = max( yOffset - yBase, 1 );
float x, y;
int i, j;
glViewport( 0, 0, winWidth, winHeight );
glDisable( GL_SCISSOR_TEST );
glClearColor( 0.0, 0.0, 0.0, 0.0 );
glClear( GL_COLOR_BUFFER_BIT );
glEnable( GL_SCISSOR_TEST );
x = xBase;
y = (winHeight - 1) - yOffset;
for ( i = 0 ; i < NUM_BASE_FORMATS ; i++ )
{
struct formatInfo *format;
if ( i == baseFormat ) {
labelInfoColor = labelColor1;
} else {
labelInfoColor = labelColor0;
}
format = &baseFormats[i].format[baseFormats[i].current];
for ( j = 0 ; j < NUM_ENV_MODES ; j++ ) {
struct envModeInfo *envMode;
envMode = &envModes[j];
drawSample( x, y, xSize, ySize, format, envMode );
x += xOffset;
}
x = xBase;
y -= yOffset;
}
if ( doubleBuffered ) {
glutSwapBuffers();
} else {
glFlush();
}
checkErrors();
}
static void usage( char *name )
{
fprintf( stderr, "usage: %s [ options ]\n", name );
fprintf( stderr, "\n" );
fprintf( stderr, "options:\n" );
fprintf( stderr, " -sb single buffered\n" );
fprintf( stderr, " -db double buffered\n" );
fprintf( stderr, " -info print OpenGL driver info\n" );
}
static void instructions( void )
{
fprintf( stderr, "texenv - texture environment and internal format test\n" );
fprintf( stderr, "\n" );
fprintf( stderr, " [c] - cycle through background colors\n" );
fprintf( stderr, " [g] - toggle background\n" );
fprintf( stderr, " [b] - toggle blend\n" );
fprintf( stderr, " [s] - toggle smooth shading\n" );
fprintf( stderr, " [t] - toggle texturing\n" );
fprintf( stderr, " [i] - toggle information display\n" );
fprintf( stderr, " up/down - select row\n" );
fprintf( stderr, " left/right - change row's internal format\n" );
}
int main( int argc, char *argv[] )
{
GLboolean info = GL_FALSE;
int i;
glutInitWindowSize( winWidth, winHeight );
glutInit( &argc, argv );
for ( i = 1 ; i < argc ; i++ ) {
if ( !strcmp( "-sb", argv[i] ) ) {
doubleBuffered = GL_FALSE;
} else if ( !strcmp( "-db", argv[i] ) ) {
doubleBuffered = GL_TRUE;
} else if ( !strcmp( "-info", argv[i] ) ) {
info = GL_TRUE;
} else {
usage( argv[0] );
exit( 1 );
}
}
if ( doubleBuffered ) {
glutInitDisplayMode( GLUT_RGB | GLUT_DOUBLE );
} else {
glutInitDisplayMode( GLUT_RGB | GLUT_SINGLE );
}
Win = glutCreateWindow( "Texture Environment Test" );
initialize();
instructions();
if ( info ) {
printf( "\n" );
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 ) );
}
#if GL_EXT_texture_env_add
if ( !glutExtensionSupported( "GL_EXT_texture_env_add" ) ) {
fprintf( stderr, "missing extension: GL_EXT_texture_env_add\n" );
NUM_ENV_MODES--;
}
#endif
glutDisplayFunc( display );
glutReshapeFunc( reshape );
glutKeyboardFunc( keyboard );
glutSpecialFunc( special );
glutMainLoop();
return 0;
}