1 files changed, 102 insertions, 0 deletions
diff --git a/progs/redbook/depthcue.c b/progs/redbook/depthcue.c
new file mode 100644
index 0000000000..41af19cf96
--- /dev/null
+++ b/progs/redbook/depthcue.c
@@ -0,0 +1,102 @@
+
+/* 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+ * Unpublished-- rights reserved under the copyright laws of the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.
+ */
+/*
+ *  depthcue.c
+ *  This program draws a wireframe model, which uses 
+ *  intensity (brightness) to give clues to distance.
+ *  Fog is used to achieve this effect.
+ */
+#include <stdlib.h>
+#include <GL/glut.h>
+
+/*  Initialize linear fog for depth cueing.
+ */
+void myinit(void)
+{
+    GLfloat fogColor[4] = {0.0, 0.0, 0.0, 1.0};
+
+    glEnable(GL_FOG);
+    glFogi (GL_FOG_MODE, GL_LINEAR);
+    glHint (GL_FOG_HINT, GL_NICEST);  /*  per pixel   */
+    glFogf (GL_FOG_START, 3.0);
+    glFogf (GL_FOG_END, 5.0);
+    glFogfv (GL_FOG_COLOR, fogColor);
+    glClearColor(0.0, 0.0, 0.0, 1.0);
+
+    glDepthFunc(GL_LESS);
+    glEnable(GL_DEPTH_TEST);
+    glShadeModel(GL_FLAT);
+}
+
+/*  display() draws an icosahedron.
+ */
+void display(void)
+{
+    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+    glColor3f (1.0, 1.0, 1.0);
+    glutWireIcosahedron();
+    glFlush();
+}
+
+void myReshape(int w, int h)
+{
+    glViewport(0, 0, w, h);
+    glMatrixMode(GL_PROJECTION);
+    glLoadIdentity();
+    gluPerspective (45.0, (GLfloat) w/(GLfloat) h, 3.0, 5.0);
+    glMatrixMode(GL_MODELVIEW);
+    glLoadIdentity ();
+    glTranslatef (0.0, 0.0, -4.0);  /*  move object into view   */
+}
+
+/*  Main Loop
+ */
+int main(int argc, char** argv)
+{
+    glutInit(&argc, argv);
+    glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB | GLUT_DEPTH);
+    glutCreateWindow(argv[0]);
+    myinit();
+    glutReshapeFunc(myReshape);
+    glutDisplayFunc(display);
+    glutMainLoop();
+    return 0;             /* ANSI C requires main to return int. */
+}
+