progs/xdemos/shape.c - third_party/mesa - Git at Google

 /* $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;
 }
	/* $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;
	}