progs/util/winpos.c

   1 /* winpos.c */
   2
   3
   4 /*
   5  * Set the current raster position to a specific window
   6  * coordinate.  Also see the GL_MESA_window_pos extension.
   7  *
   8  * Written by Brian Paul and in the public domain.
   9  */
  10
  11
  12 void WindowPos( GLfloat x, GLfloat y, GLfloat z )
  13 {
  14    GLfloat fx, fy;
  15
  16    /* Push current matrix mode and viewport attributes */
  17    glPushAttrib( GL_TRANSFORM_BIT | GL_VIEWPORT_BIT );
  18
  19    /* Setup projection parameters */
  20    glMatrixMode( GL_PROJECTION );
  21    glPushMatrix();
  22    glLoadIdentity();
  23    glMatrixMode( GL_MODELVIEW );
  24    glPushMatrix();
  25    glLoadIdentity();
  26
  27    glDepthRange( z, z );
  28    glViewport( (int) x - 1, (int) y - 1, 2, 2 );
  29
  30    /* set the raster (window) position */
  31    fx = x - (int) x;
  32    fy = y - (int) y;
  33    glRasterPos3f( fx, fy, 0.0 );
  34
  35    /* restore matrices, viewport and matrix mode */
  36    glPopMatrix();
  37    glMatrixMode( GL_PROJECTION );
  38    glPopMatrix();
  39
  40    glPopAttrib();
  41 }
  42