progs/util/idproj.c

   1 /* idproj.c */
   2
   3
   4 /*
   5  * Setup an identity projection such that glVertex(x,y) maps to
   6  * window coordinate (x,y).
   7  *
   8  * Written by Brian Paul and in the public domain.
   9  */
  10
  11
  12
  13
  14
  15 void IdentityProjection( GLint x, GLint y, GLsizei width, GLsizei height )
  16 {
  17    glViewport( x, y, width, height );
  18    glMatrixMode( GL_PROJECTION );
  19    glLoadIdentity();
  20    glOrtho( (GLdouble) x, (GLdouble) y,
  21             (GLdouble) width, (GLdouble) height,
  22             -1.0, 1.0 );
  23    glMatrixMode( GL_MODELVIEW );
  24    glLoadIdentity();
  25 }
  26