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Diffstat (limited to 'progs/demos/texobj.c')
| -rw-r--r-- | progs/demos/texobj.c | 284 |
1 files changed, 284 insertions, 0 deletions
diff --git a/progs/demos/texobj.c b/progs/demos/texobj.c new file mode 100644 index 000000000..40bce6e56 --- /dev/null +++ b/progs/demos/texobj.c @@ -0,0 +1,284 @@ + +/* + * Example of using the 1.1 texture object functions. + * Also, this demo utilizes Mesa's fast texture map path. + * + * Brian Paul June 1996 This file is in the public domain. + */ + +#include <assert.h> +#include <math.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include "GL/glut.h" + +static GLuint Window = 0; + +static GLuint TexObj[2]; +static GLfloat Angle = 0.0f; +static GLboolean UseObj = GL_FALSE; + + +#if defined(GL_VERSION_1_1) || defined(GL_VERSION_1_2) +# define TEXTURE_OBJECT 1 +#elif defined(GL_EXT_texture_object) +# define TEXTURE_OBJECT 1 +# define glBindTexture(A,B) glBindTextureEXT(A,B) +# define glGenTextures(A,B) glGenTexturesEXT(A,B) +# define glDeleteTextures(A,B) glDeleteTexturesEXT(A,B) +#endif + + + + +static void draw( void ) +{ + glClear( GL_COLOR_BUFFER_BIT ); + + glColor3f( 1.0, 1.0, 1.0 ); + + /* draw first polygon */ + glPushMatrix(); + glTranslatef( -1.0, 0.0, 0.0 ); + glRotatef( Angle, 0.0, 0.0, 1.0 ); + if (UseObj) { +#ifdef TEXTURE_OBJECT + glBindTexture( GL_TEXTURE_2D, TexObj[0] ); +#endif + } + else { + glCallList( TexObj[0] ); + } + glBegin( GL_POLYGON ); + glTexCoord2f( 0.0, 0.0 ); glVertex2f( -1.0, -1.0 ); + glTexCoord2f( 1.0, 0.0 ); glVertex2f( 1.0, -1.0 ); + glTexCoord2f( 1.0, 1.0 ); glVertex2f( 1.0, 1.0 ); + glTexCoord2f( 0.0, 1.0 ); glVertex2f( -1.0, 1.0 ); + glEnd(); + glPopMatrix(); + + /* draw second polygon */ + glPushMatrix(); + glTranslatef( 1.0, 0.0, 0.0 ); + glRotatef( Angle-90.0, 0.0, 1.0, 0.0 ); + if (UseObj) { +#ifdef TEXTURE_OBJECT + glBindTexture( GL_TEXTURE_2D, TexObj[1] ); +#endif + } + else { + glCallList( TexObj[1] ); + } + glBegin( GL_POLYGON ); + glTexCoord2f( 0.0, 0.0 ); glVertex2f( -1.0, -1.0 ); + glTexCoord2f( 1.0, 0.0 ); glVertex2f( 1.0, -1.0 ); + glTexCoord2f( 1.0, 1.0 ); glVertex2f( 1.0, 1.0 ); + glTexCoord2f( 0.0, 1.0 ); glVertex2f( -1.0, 1.0 ); + glEnd(); + glPopMatrix(); + + glutSwapBuffers(); +} + + + +static void idle( void ) +{ + static double t0 = -1.; + double dt, t = glutGet(GLUT_ELAPSED_TIME) / 1000.0; + if (t0 < 0.0) + t0 = t; + dt = t - t0; + t0 = t; + Angle += 120.0*dt; + glutPostRedisplay(); +} + + + +/* change view Angle, exit upon ESC */ +static void key(unsigned char k, int x, int y) +{ + (void) x; + (void) y; + switch (k) { + case 27: +#ifdef TEXTURE_OBJECT + glDeleteTextures( 2, TexObj ); +#endif + glutDestroyWindow(Window); + exit(0); + } +} + + + +/* new window size or exposure */ +static void reshape( int width, int height ) +{ + glViewport(0, 0, (GLint)width, (GLint)height); + glMatrixMode(GL_PROJECTION); + glLoadIdentity(); + /* glOrtho( -3.0, 3.0, -3.0, 3.0, -10.0, 10.0 );*/ + glFrustum( -2.0, 2.0, -2.0, 2.0, 6.0, 20.0 ); + glMatrixMode(GL_MODELVIEW); + glLoadIdentity(); + glTranslatef( 0.0, 0.0, -8.0 ); +} + + +static void init( void ) +{ + static int width=8, height=8; + static GLubyte tex1[] = { + 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 0, 1, 0, 0, 0, + 0, 0, 0, 1, 1, 0, 0, 0, + 0, 0, 0, 0, 1, 0, 0, 0, + 0, 0, 0, 0, 1, 0, 0, 0, + 0, 0, 0, 0, 1, 0, 0, 0, + 0, 0, 0, 1, 1, 1, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0 }; + + static GLubyte tex2[] = { + 0, 0, 0, 0, 0, 0, 0, 0, + 0, 0, 0, 2, 2, 0, 0, 0, + 0, 0, 2, 0, 0, 2, 0, 0, + 0, 0, 0, 0, 0, 2, 0, 0, + 0, 0, 0, 0, 2, 0, 0, 0, + 0, 0, 0, 2, 0, 0, 0, 0, + 0, 0, 2, 2, 2, 2, 0, 0, + 0, 0, 0, 0, 0, 0, 0, 0 }; + + GLubyte tex[64][3]; + GLint i, j; + + + glDisable( GL_DITHER ); + + /* Setup texturing */ + glEnable( GL_TEXTURE_2D ); + glTexEnvi( GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_DECAL ); + glHint( GL_PERSPECTIVE_CORRECTION_HINT, GL_FASTEST ); + + + /* generate texture object IDs */ + if (UseObj) { +#ifdef TEXTURE_OBJECT + glGenTextures( 2, TexObj ); +#endif + } + else { + TexObj[0] = glGenLists(2); + TexObj[1] = TexObj[0]+1; + } + + /* setup first texture object */ + if (UseObj) { +#ifdef TEXTURE_OBJECT + glBindTexture( GL_TEXTURE_2D, TexObj[0] ); + assert(glIsTexture(TexObj[0])); +#endif + } + else { + glNewList( TexObj[0], GL_COMPILE ); + } + /* red on white */ + for (i=0;i<height;i++) { + for (j=0;j<width;j++) { + int p = i*width+j; + if (tex1[(height-i-1)*width+j]) { + tex[p][0] = 255; tex[p][1] = 0; tex[p][2] = 0; + } + else { + tex[p][0] = 255; tex[p][1] = 255; tex[p][2] = 255; + } + } + } + + glTexImage2D( GL_TEXTURE_2D, 0, 3, width, height, 0, + GL_RGB, GL_UNSIGNED_BYTE, tex ); + 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_REPEAT ); + glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT ); + if (!UseObj) { + glEndList(); + } + /* end of texture object */ + + /* setup second texture object */ + if (UseObj) { +#ifdef TEXTURE_OBJECT + glBindTexture( GL_TEXTURE_2D, TexObj[1] ); + assert(glIsTexture(TexObj[1])); +#endif + assert(!glIsTexture(TexObj[1] + 999)); + } + else { + glNewList( TexObj[1], GL_COMPILE ); + } + /* green on blue */ + for (i=0;i<height;i++) { + for (j=0;j<width;j++) { + int p = i*width+j; + if (tex2[(height-i-1)*width+j]) { + tex[p][0] = 0; tex[p][1] = 255; tex[p][2] = 0; + } + else { + tex[p][0] = 0; tex[p][1] = 0; tex[p][2] = 255; + } + } + } + glTexImage2D( GL_TEXTURE_2D, 0, 3, width, height, 0, + GL_RGB, GL_UNSIGNED_BYTE, tex ); + 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_REPEAT ); + glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT ); + if (!UseObj) { + glEndList(); + } + /* end texture object */ + +} + + + +int main( int argc, char *argv[] ) +{ + glutInit(&argc, argv); + glutInitWindowPosition(0, 0); + glutInitWindowSize(300, 300); + glutInitDisplayMode( GLUT_RGB | GLUT_DEPTH | GLUT_DOUBLE ); + + Window = glutCreateWindow("Texture Objects"); + if (!Window) { + exit(1); + } + + /* check that renderer has the GL_EXT_texture_object extension + * or supports OpenGL 1.1 + */ +#ifdef TEXTURE_OBJECT + { + char *exten = (char *) glGetString( GL_EXTENSIONS ); + char *version = (char *) glGetString( GL_VERSION ); + if ( strstr( exten, "GL_EXT_texture_object" ) + || strncmp( version, "1.1", 3 )==0 + || strncmp( version, "1.2", 3 )==0 ) { + UseObj = GL_TRUE; + } + } +#endif + + init(); + + glutReshapeFunc( reshape ); + glutKeyboardFunc( key ); + glutIdleFunc( idle ); + glutDisplayFunc( draw ); + glutMainLoop(); + return 0; +} |