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diff --git a/progs/xdemos/shape.c b/progs/xdemos/shape.c
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+/* $Id: shape.c,v 1.1 1999/08/19 00:55:43 jtg Exp $ */
+
+/*
+ * Example of using the X "shape" extension with OpenGL:  render a spinning
+ * cube inside of a non-rectangular window.
+ *
+ * Press ESC to exit.  Press up/down to change window shape.
+ *
+ * To compile add "shape" to the PROGS list in Makefile.
+ *
+ * Brian Paul
+ * June 16, 1997
+ *
+ * This program is in the public domain.
+ */
+
+
+#include <math.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <X11/Xlib.h>
+#include <X11/Xutil.h>
+#include <X11/keysym.h>
+#include <X11/extensions/shape.h>
+#include <GL/glx.h>
+
+#ifndef PI
+#define PI 3.1415926
+#endif
+
+
+static int Width=500, Height=500;
+
+static float Xangle = 0.0, Yangle = 0.0;
+static int Redraw = 0;
+static int Sides = 5;
+static int MinSides = 3;
+static int MaxSides = 20;
+
+
+/*
+ * Draw the OpenGL stuff and do a SwapBuffers.
+ */
+static void display(Display *dpy, Window win)
+{
+   float scale = 1.7;
+
+   glClear(GL_COLOR_BUFFER_BIT);
+
+   glPushMatrix();
+
+   glScalef(scale, scale, scale);
+   glRotatef(Xangle, 1.0, 0.0, 0.0);
+   glRotatef(Yangle, 0.0, 1.0, 0.0);
+
+   glColor3f(1.0, 1.0, 1.0);
+   glBegin(GL_LINE_LOOP);
+   glVertex3f(-1.0, -1.0, -1.0);
+   glVertex3f( 1.0, -1.0, -1.0);
+   glVertex3f( 1.0,  1.0, -1.0);
+   glVertex3f(-1.0,  1.0, -1.0);
+   glEnd();
+
+   glBegin(GL_LINE_LOOP);
+   glVertex3f(-1.0, -1.0, 1.0);
+   glVertex3f( 1.0, -1.0, 1.0);
+   glVertex3f( 1.0,  1.0, 1.0);
+   glVertex3f(-1.0,  1.0, 1.0);
+   glEnd();
+
+   glBegin(GL_LINES);
+   glVertex3f(-1.0, -1.0, -1.0);   glVertex3f(-1.0, -1.0, 1.0);
+   glVertex3f( 1.0, -1.0, -1.0);   glVertex3f( 1.0, -1.0, 1.0);
+   glVertex3f( 1.0,  1.0, -1.0);   glVertex3f( 1.0,  1.0, 1.0);
+   glVertex3f(-1.0,  1.0, -1.0);   glVertex3f(-1.0,  1.0, 1.0);
+   glEnd();
+
+   glPopMatrix();
+
+   glXSwapBuffers(dpy, win);
+}
+
+
+/*
+ * Called when no events are pending.
+ */
+static void idle(void)
+{
+   Xangle += 2.0;
+   Yangle += 3.3;
+   Redraw = 1;
+}
+
+
+/*
+ * This is called when we have to recompute the window shape bitmask.
+ * We just generate an n-sided regular polygon here but any other shape
+ * would be possible.
+ */
+static void make_shape_mask(Display *dpy, Window win, int width, int height,
+                            int sides)
+{
+   Pixmap shapeMask;
+   XGCValues xgcv;
+   GC gc;
+
+   /* allocate 1-bit deep pixmap and a GC */
+   shapeMask = XCreatePixmap(dpy, win, width, height, 1);
+   gc = XCreateGC(dpy, shapeMask, 0, &xgcv);
+
+   /* clear shapeMask to zeros */
+   XSetForeground(dpy, gc, 0);
+   XFillRectangle(dpy, shapeMask, gc, 0, 0, width, height);
+
+   /* draw mask */
+   XSetForeground(dpy, gc, 1);
+   {
+      int cx = width / 2;
+      int cy = height / 2;
+      float angle = 0.0;
+      float step = 2.0 * PI / sides;
+      float radius = width / 2;
+      int i;
+      XPoint points[100];
+      for (i=0;i<sides;i++) {
+         int x = cx + radius * sin(angle);
+         int y = cy - radius * cos(angle);
+         points[i].x = x;
+         points[i].y = y;
+         angle += step;
+      }
+      XFillPolygon(dpy, shapeMask, gc, points, sides, Convex, CoordModeOrigin);
+   }
+
+   /* This is the only SHAPE extension call- simple! */
+   XShapeCombineMask(dpy, win, ShapeBounding, 0, 0, shapeMask, ShapeSet);
+
+   XFreeGC(dpy, gc);
+   XFreePixmap(dpy, shapeMask);
+}
+
+
+/*
+ * Called when window is resized.  Do OpenGL viewport and projection stuff.
+ */
+static void reshape(int width, int height)
+{
+   glViewport(0, 0, width, height);
+   glMatrixMode(GL_PROJECTION);
+   glLoadIdentity();
+   glFrustum(-1.0, 1.0, -1.0, 1.0, 3.0, 20.0);
+   glMatrixMode(GL_MODELVIEW);
+   glLoadIdentity();
+   glTranslatef(0.0, 0.0, -10.0);
+}
+
+
+/*
+ * Process X events.
+ */
+static void event_loop(Display *dpy, Window win)
+{
+   while (1) {
+      XEvent event;
+      if (XPending(dpy)) {
+         XNextEvent(dpy, &event);
+         switch (event.type) {
+            case Expose:
+               display(dpy, event.xexpose.window);
+               break;
+            case ConfigureNotify:
+               Width = event.xconfigure.width;
+               Height = event.xconfigure.height,
+               make_shape_mask(dpy, win, Width, Height, Sides);
+               reshape(Width, Height);
+               break;
+            case KeyPress:
+               {
+                  char buf[100];
+                  KeySym keySym;
+                  XComposeStatus stat;
+                  XLookupString(&event.xkey, buf, sizeof(buf), &keySym, &stat);
+                  switch (keySym) {
+                     case XK_Escape:
+                        exit(0);
+                        break;
+                     case XK_Up:
+                        Sides++;
+                        if (Sides>MaxSides) Sides = MaxSides;
+                        make_shape_mask(dpy, win, Width, Height, Sides);
+                        break;
+                     case XK_Down:
+                        Sides--;
+                        if (Sides<MinSides) Sides = MinSides;
+                        make_shape_mask(dpy, win, Width, Height, Sides);
+                        break;
+                  }
+               }
+               break;
+            default:
+               ;;
+         }
+      }
+      else {
+         idle();
+         if (Redraw) {
+            display(dpy, win);
+            Redraw = 0;
+         }
+      }
+   }
+}
+
+
+/*
+ * Allocate a "nice" colormap.  This could be better (HP-CR support, etc).
+ */
+static Colormap alloc_colormap(Display *dpy, Window parent, Visual *vis)
+{
+   Screen *scr = DefaultScreenOfDisplay(dpy);
+   int scrnum = DefaultScreen(dpy);
+
+   if (MaxCmapsOfScreen(scr)==1 && vis==DefaultVisual(dpy, scrnum)) {
+      /* The window and root are of the same visual type so */
+      /* share the root colormap. */
+      return DefaultColormap(dpy, scrnum);
+   }
+   else {
+      return XCreateColormap(dpy, parent, vis, AllocNone);
+   }
+}
+
+
+int main(int argc, char *argv[])
+{
+   static int glAttribs[] = {
+      GLX_DOUBLEBUFFER,
+      GLX_RGBA,
+      GLX_DEPTH_SIZE, 1,
+      None
+   };
+   Display *dpy;
+   XVisualInfo *visInfo;
+   int scrn;
+   Window root;
+   Colormap cmap;
+   Window win;
+   XSetWindowAttributes winAttribs;
+   unsigned long winAttribsMask;
+   GLXContext glCtx;
+   int ignore;
+
+   dpy = XOpenDisplay(NULL);
+   if (!dpy) {
+      fprintf(stderr, "Couldn't open default display\n");
+      return 1;
+   }
+
+   /* check that we can use the shape extension */
+   if (!XQueryExtension(dpy, "SHAPE", &ignore, &ignore, &ignore )) {
+      fprintf(stderr, "Display doesn't support shape extension\n");
+      return 1;
+   }
+
+   scrn = DefaultScreen(dpy);
+
+   root = RootWindow(dpy, scrn);
+
+   visInfo = glXChooseVisual(dpy, scrn, glAttribs);
+   if (!visInfo) {
+      fprintf(stderr, "Couldn't get RGB, DB, Z visual\n");
+      return 1;
+   }
+
+   glCtx = glXCreateContext(dpy, visInfo, 0, True);
+   if (!glCtx) {
+      fprintf(stderr, "Couldn't create GL context\n");
+      return 1;
+   }
+
+   cmap = alloc_colormap(dpy, root, visInfo->visual);
+   if (!cmap) {
+      fprintf(stderr, "Couln't create colormap\n");
+      return 1;
+   }
+
+   winAttribs.border_pixel = 0;
+   winAttribs.colormap = cmap;
+   winAttribs.event_mask = StructureNotifyMask | ExposureMask | KeyPressMask;
+   winAttribsMask = CWBorderPixel | CWColormap | CWEventMask;
+   win = XCreateWindow(dpy, root, 0, 0, Width, Height, 0,
+                       visInfo->depth, InputOutput,
+                       visInfo->visual,
+                       winAttribsMask, &winAttribs);
+   XMapWindow(dpy, win);
+
+   glXMakeCurrent(dpy, win, glCtx);
+
+   printf("Press ESC to exit.\n");
+   printf("Press up/down to change window shape.\n");
+
+   event_loop(dpy, win);
+
+   return 0;
+}