Added ESC key handling

progs/redbook/pickdepth.c

@@ -3,14 +3,14 @@
 
 /*
  * (c) Copyright 1993, Silicon Graphics, Inc.
- * ALL RIGHTS RESERVED 
- * Permission to use, copy, modify, and distribute this software for 
+ * 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 
+ * 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. 
+ * 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,
@@ -24,8 +24,8 @@
  * 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 
+ *
+ * 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
@@ -39,19 +39,19 @@
  */
 /*
  *  pickdepth.c
- *  Picking is demonstrated in this program.  In 
- *  rendering mode, three overlapping rectangles are 
- *  drawn.  When the left mouse button is pressed, 
- *  selection mode is entered with the picking matrix.  
+ *  Picking is demonstrated in this program.  In
+ *  rendering mode, three overlapping rectangles are
+ *  drawn.  When the left mouse button is pressed,
+ *  selection mode is entered with the picking matrix.
  *  Rectangles which are drawn under the cursor position
- *  are "picked."  Pay special attention to the depth 
+ *  are "picked."  Pay special attention to the depth
  *  value range, which is returned.
  */
 #include <stdlib.h>
 #include <stdio.h>
 #include <GL/glut.h>
 
-void 
+void
 myinit(void)
 {
   glClearColor(0.0, 0.0, 0.0, 0.0);
@@ -61,11 +61,11 @@ myinit(void)
   glDepthRange(0.0, 1.0);  /* The default z mapping */
 }
 
-/*  The three rectangles are drawn.  In selection mode, 
- *  each rectangle is given the same name.  Note that 
+/*  The three rectangles are drawn.  In selection mode,
+ *  each rectangle is given the same name.  Note that
  *  each rectangle is drawn with a different z value.
  */
-void 
+void
 drawRects(GLenum mode)
 {
   if (mode == GL_SELECT)
@@ -97,10 +97,10 @@ drawRects(GLenum mode)
   glEnd();
 }
 
-/*  processHits() prints out the contents of the 
+/*  processHits() prints out the contents of the
  *  selection array.
  */
-void 
+void
 processHits(GLint hits, GLuint buffer[])
 {
   unsigned int i, j;
@@ -125,13 +125,13 @@ processHits(GLint hits, GLuint buffer[])
   }
 }
 
-/*  pickRects() sets up selection mode, name stack, 
- *  and projection matrix for picking.  Then the objects 
+/*  pickRects() sets up selection mode, name stack,
+ *  and projection matrix for picking.  Then the objects
  *  are drawn.
  */
 #define BUFSIZE 512
 
-void 
+void
 pickRects(int button, int state, int x, int y)
 {
   GLuint selectBuf[BUFSIZE];
@@ -164,7 +164,7 @@ pickRects(int button, int state, int x, int y)
   processHits(hits, selectBuf);
 }
 
-void 
+void
 display(void)
 {
   glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
@@ -172,7 +172,7 @@ display(void)
   glutSwapBuffers();
 }
 
-void 
+void
 myReshape(int w, int h)
 {
   glViewport(0, 0, w, h);
@@ -183,8 +183,21 @@ myReshape(int w, int h)
   glLoadIdentity();
 }
 
+static void
+key(unsigned char k, int x, int y)
+{
+  switch (k) {
+  case 27:  /* Escape */
+    exit(0);
+    break;
+  default:
+    return;
+  }
+  glutPostRedisplay();
+}
+
 /*  Main Loop
- *  Open window with initial window size, title bar, 
+ *  Open window with initial window size, title bar,
  *  RGBA display mode, depth buffer, and handle input events.
  */
 int
@@ -198,6 +211,7 @@ main(int argc, char **argv)
   glutMouseFunc(pickRects);
   glutReshapeFunc(myReshape);
   glutDisplayFunc(display);
+  glutKeyboardFunc(key);
   glutMainLoop();
   return 0;             /* ANSI C requires main to return int. */
 }