progs/miniglx/texline.c

   1
   2 /*
   3  * Test textured lines.
   4  *
   5  * Brian Paul
   6  * September 2000
   7  */
   8
   9
  10 #include <stdio.h>
  11 #include <stdlib.h>
  12 #include <math.h>
  13 #include <GL/glut.h>
  14 #include "../util/readtex.c"   /* I know, this is a hack. */
  15
  16 #define TEXTURE_FILE "../images/girl.rgb"
  17
  18 static GLboolean Antialias = GL_FALSE;
  19 static GLboolean Animate = GL_FALSE;
  20 static GLint Texture = 1;
  21 static GLboolean Stipple = GL_FALSE;
  22 static GLfloat LineWidth = 1.0;
  23
  24 static GLfloat Xrot = -60.0, Yrot = 0.0, Zrot = 0.0;
  25 static GLfloat DYrot = 1.0;
  26 static GLboolean Points = GL_FALSE;
  27 static GLfloat Scale = 1.0;
  28
  29 static void Idle( void )
  30 {
  31    if (Animate) {
  32       Zrot += DYrot;
  33       glutPostRedisplay();
  34    }
  35 }
  36
  37
  38 static void Display( void )
  39 {
  40    GLfloat x, y, s, t;
  41
  42    glClear( GL_COLOR_BUFFER_BIT );
  43
  44    glPushMatrix();
  45    glRotatef(Xrot, 1.0, 0.0, 0.0);
  46    glRotatef(Yrot, 0.0, 1.0, 0.0);
  47    glRotatef(Zrot, 0.0, 0.0, 1.0);
  48    glScalef(Scale, Scale, Scale);
  49
  50    if (Texture)
  51       glColor3f(1, 1, 1);
  52
  53    if (Points) {
  54       glBegin(GL_POINTS);
  55       for (t = 0.0; t <= 1.0; t += 0.025) {
  56          for (s = 0.0; s <= 1.0; s += 0.025) {
  57             x = s * 2.0 - 1.0;
  58             y = t * 2.0 - 1.0;
  59             if (!Texture)
  60                glColor3f(1, 0, 1);
  61             glMultiTexCoord2fARB(GL_TEXTURE1_ARB, t, s);
  62             glTexCoord2f(s, t);
  63             glVertex2f(x, y);
  64          }
  65       }
  66       glEnd();
  67    }
  68    else {
  69       glBegin(GL_LINES);
  70       for (t = 0.0; t <= 1.0; t += 0.025) {
  71          x = t * 2.0 - 1.0;
  72          if (!Texture)
  73             glColor3f(1, 0, 1);
  74          glTexCoord2f(t, 0.0);
  75          glMultiTexCoord2fARB(GL_TEXTURE1_ARB, 0.0, t);
  76          glVertex2f(x, -1.0);
  77          if (!Texture)
  78             glColor3f(0, 1, 0);
  79          glTexCoord2f(t, 1.0);
  80          glMultiTexCoord2fARB(GL_TEXTURE1_ARB, 1.0, t);
  81          glVertex2f(x, 1.0);
  82       }
  83       glEnd();
  84    }
  85
  86    glPopMatrix();
  87
  88    glutSwapBuffers();
  89 }
  90
  91
  92 static void Reshape( int width, int height )
  93 {
  94    GLfloat ar = (float) width / height;
  95    glViewport( 0, 0, width, height );
  96    glMatrixMode( GL_PROJECTION );
  97    glLoadIdentity();
  98    glFrustum( -ar, ar, -1.0, 1.0, 10.0, 100.0 );
  99    glMatrixMode( GL_MODELVIEW );
 100    glLoadIdentity();
 101    glTranslatef( 0.0, 0.0, -12.0 );
 102 }
 103
 104
 105 static void Key( unsigned char key, int x, int y )
 106 {
 107    (void) x;
 108    (void) y;
 109    switch (key) {
 110       case 'a':
 111          Antialias = !Antialias;
 112          if (Antialias) {
 113             glEnable(GL_LINE_SMOOTH);
 114             glEnable(GL_POINT_SMOOTH);
 115             glEnable(GL_BLEND);
 116             glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
 117          }
 118          else {
 119             glDisable(GL_LINE_SMOOTH);
 120             glDisable(GL_POINT_SMOOTH);
 121             glDisable(GL_BLEND);
 122          }
 123          break;
 124       case 't':
 125          Texture++;
 126          if (Texture > 2)
 127             Texture = 0;
 128          if (Texture == 0) {
 129             glActiveTextureARB(GL_TEXTURE0_ARB);
 130             glDisable(GL_TEXTURE_2D);
 131             glActiveTextureARB(GL_TEXTURE1_ARB);
 132             glDisable(GL_TEXTURE_2D);
 133          }
 134          else if (Texture == 1) {
 135             glActiveTextureARB(GL_TEXTURE0_ARB);
 136             glEnable(GL_TEXTURE_2D);
 137             glActiveTextureARB(GL_TEXTURE1_ARB);
 138             glDisable(GL_TEXTURE_2D);
 139          }
 140          else {
 141             glActiveTextureARB(GL_TEXTURE0_ARB);
 142             glEnable(GL_TEXTURE_2D);
 143             glActiveTextureARB(GL_TEXTURE1_ARB);
 144             glEnable(GL_TEXTURE_2D);
 145          }
 146          break;
 147       case 'w':
 148          LineWidth -= 0.25;
 149          if (LineWidth < 0.25)
 150             LineWidth = 0.25;
 151          glLineWidth(LineWidth);
 152          glPointSize(LineWidth);
 153          break;
 154       case 'W':
 155          LineWidth += 0.25;
 156          if (LineWidth > 8.0)
 157             LineWidth = 8.0;
 158          glLineWidth(LineWidth);
 159          glPointSize(LineWidth);
 160          break;
 161       case 'p':
 162          Points = !Points;
 163          break;
 164       case 's':
 165          Stipple = !Stipple;
 166          if (Stipple)
 167             glEnable(GL_LINE_STIPPLE);
 168          else
 169             glDisable(GL_LINE_STIPPLE);
 170          break;
 171       case ' ':
 172          Animate = !Animate;
 173          if (Animate)
 174             glutIdleFunc(Idle);
 175          else
 176             glutIdleFunc(NULL);
 177          break;
 178       case 27:
 179          exit(0);
 180          break;
 181    }
 182    printf("LineWidth, PointSize = %f\n", LineWidth);
 183    glutPostRedisplay();
 184 }
 185
 186
 187 static void SpecialKey( int key, int x, int y )
 188 {
 189    float step = 3.0;
 190    (void) x;
 191    (void) y;
 192
 193    switch (key) {
 194       case GLUT_KEY_UP:
 195          Xrot += step;
 196          break;
 197       case GLUT_KEY_DOWN:
 198          Xrot -= step;
 199          break;
 200       case GLUT_KEY_LEFT:
 201          Yrot += step;
 202          break;
 203       case GLUT_KEY_RIGHT:
 204          Yrot -= step;
 205          break;
 206    }
 207    glutPostRedisplay();
 208 }
 209
 210
 211 static void Init( int argc, char *argv[] )
 212 {
 213    GLuint u;
 214    for (u = 0; u < 2; u++) {
 215       glActiveTextureARB(GL_TEXTURE0_ARB + u);
 216       glBindTexture(GL_TEXTURE_2D, 10+u);
 217       if (u == 0)
 218          glEnable(GL_TEXTURE_2D);
 219       glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
 220       glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
 221       glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 222       glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
 223
 224       if (u == 0)
 225          glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
 226       else
 227          glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_ADD);
 228
 229       glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
 230       if (!LoadRGBMipmaps(TEXTURE_FILE, GL_RGB)) {
 231          printf("Error: couldn't load texture image\n");
 232          exit(1);
 233       }
 234    }
 235
 236    glLineStipple(1, 0xff);
 237
 238    if (argc > 1 && strcmp(argv[1], "-info")==0) {
 239       printf("GL_RENDERER   = %s\n", (char *) glGetString(GL_RENDERER));
 240       printf("GL_VERSION    = %s\n", (char *) glGetString(GL_VERSION));
 241       printf("GL_VENDOR     = %s\n", (char *) glGetString(GL_VENDOR));
 242       printf("GL_EXTENSIONS = %s\n", (char *) glGetString(GL_EXTENSIONS));
 243    }
 244 }
 245
 246
 247 int main( int argc, char *argv[] )
 248 {
 249    glutInit( &argc, argv );
 250    glutInitWindowSize( 400, 300 );
 251
 252    glutInitDisplayMode( GLUT_RGB | GLUT_DOUBLE );
 253
 254    glutCreateWindow(argv[0] );
 255
 256    Init(argc, argv);
 257
 258    glutReshapeFunc( Reshape );
 259    glutKeyboardFunc( Key );
 260    glutSpecialFunc( SpecialKey );
 261    glutDisplayFunc( Display );
 262    if (Animate)
 263       glutIdleFunc( Idle );
 264
 265    glutMainLoop();
 266    return 0;
 267 }