/* xscreensaver, Copyright (c) 1992, 1993, 1994, 1997, 1998 * Jamie Zawinski * * Permission to use, copy, modify, distribute, and sell this software and its * documentation for any purpose is hereby granted without fee, provided that * the above copyright notice appear in all copies and that both that * copyright notice and this permission notice appear in supporting * documentation. No representations are made about the suitability of this * software for any purpose. It is provided "as is" without express or * implied warranty. */ /* This file contains code for grabbing an image of the screen to hack its bits. This is a little tricky, since doing this involves the need to tell the difference between drawing on the actual root window, and on the fake root window used by the screensaver, since at this level the illusion breaks down... */ #include "utils.h" #include "yarandom.h" #include #include #ifdef HAVE_XMU # ifndef VMS # include # else /* VMS */ # include # endif /* VMS */ #endif #include "usleep.h" #include "colors.h" #include "grabscreen.h" #include "sgivideo.h" #include "visual.h" #include "resources.h" #include "vroot.h" #undef RootWindowOfScreen #undef RootWindow #undef DefaultRootWindow #ifdef HAVE_READ_DISPLAY_EXTENSION # include static Bool read_display (Screen *, Window, Pixmap, Bool); #endif /* HAVE_READ_DISPLAY_EXTENSION */ static void copy_default_colormap_contents (Screen *, Colormap, Visual *); #if defined(HAVE_READ_DISPLAY_EXTENSION) || defined(HAVE_SGI_VIDEO) static void make_cubic_colormap (Screen *, Window, Visual *); #endif static Bool MapNotify_event_p (Display *dpy, XEvent *event, XPointer window) { return (event->xany.type == MapNotify && event->xvisibility.window == (Window) window); } #ifdef DEBUG extern char *progname; #endif /* DEBUG */ static void raise_window(Display *dpy, Window window, Bool dont_wait) { #ifdef DEBUG fprintf(stderr, "%s: raising window 0x%08lX (%s)\n", progname, (unsigned long) window, (dont_wait ? "not waiting" : "waiting")); #endif /* DEBUG */ if (! dont_wait) { XWindowAttributes xgwa; XSizeHints hints; long supplied = 0; memset(&hints, 0, sizeof(hints)); XGetWMNormalHints(dpy, window, &hints, &supplied); XGetWindowAttributes (dpy, window, &xgwa); hints.x = xgwa.x; hints.y = xgwa.y; hints.width = xgwa.width; hints.height = xgwa.height; hints.flags |= (PPosition|USPosition|PSize|USSize); XSetWMNormalHints(dpy, window, &hints); } XMapRaised(dpy, window); if (! dont_wait) { XEvent event; XIfEvent (dpy, &event, MapNotify_event_p, (XPointer) window); XSync (dpy, True); } } static Bool xscreensaver_window_p (Display *dpy, Window window) { Atom type; int format; unsigned long nitems, bytesafter; char *version; if (XGetWindowProperty (dpy, window, XInternAtom (dpy, "_SCREENSAVER_VERSION", False), 0, 1, False, XA_STRING, &type, &format, &nitems, &bytesafter, (unsigned char **) &version) == Success && type != None) return True; return False; } static XErrorHandler old_ehandler = 0; static int BadWindow_ehandler (Display *dpy, XErrorEvent *error) { if (error->error_code == BadWindow || error->error_code == BadDrawable) return 0; else if (!old_ehandler) { abort(); return 0; } else return (*old_ehandler) (dpy, error); } /* XCopyArea seems not to work right on SGI O2s if you draw in SubwindowMode on a window whose depth is not the maximal depth of the screen? Or something. Anyway, things don't work unless we: use SubwindowMode for the real root window (or a legitimate virtual root window); but do not use SubwindowMode for the xscreensaver window. I make no attempt to explain. */ Bool use_subwindow_mode_p(Screen *screen, Window window) { if (window != VirtualRootWindowOfScreen(screen)) return False; else if (xscreensaver_window_p(DisplayOfScreen(screen), window)) return False; else return True; } /* Install the colormaps of all visible windows, deepest first. This should leave the colormaps of the topmost windows installed (if only N colormaps can be installed at a time, then only the topmost N windows will be shown in the right colors.) */ static void install_screen_colormaps (Screen *screen) { int i; Display *dpy = DisplayOfScreen (screen); Window vroot, real_root; Window parent, *kids = 0; unsigned int nkids = 0; XSync (dpy, False); old_ehandler = XSetErrorHandler (BadWindow_ehandler); vroot = VirtualRootWindowOfScreen (screen); if (XQueryTree (dpy, vroot, &real_root, &parent, &kids, &nkids)) for (i = 0; i < nkids; i++) { XWindowAttributes xgwa; Window client; #ifdef HAVE_XMU /* #### need to put XmuClientWindow() in xmu.c, sigh... */ if (! (client = XmuClientWindow (dpy, kids[i]))) #endif client = kids[i]; xgwa.colormap = 0; XGetWindowAttributes (dpy, client, &xgwa); if (xgwa.colormap && xgwa.map_state == IsViewable) XInstallColormap (dpy, xgwa.colormap); } XInstallColormap (dpy, DefaultColormapOfScreen (screen)); XSync (dpy, False); XSetErrorHandler (old_ehandler); XSync (dpy, False); if (kids) XFree ((char *) kids); } static void grab_screen_image_1 (Screen *screen, Window window) { Display *dpy = DisplayOfScreen (screen); XWindowAttributes xgwa; Window real_root = XRootWindowOfScreen (screen); /* not vroot */ Bool root_p = (window == real_root); Bool saver_p = xscreensaver_window_p (dpy, window); Bool grab_mouse_p = False; int unmap_time = 0; if (saver_p) /* I think this is redundant, but just to be safe... */ root_p = False; if (saver_p) /* The only time grabbing the mouse is important is if this program is being run while the saver is locking the screen. */ grab_mouse_p = True; if (!root_p) { double unmap = 0; if (saver_p) { unmap = get_float_resource("grabRootDelay", "Seconds"); if (unmap <= 0.00001 || unmap > 20) unmap = 2.5; } else { unmap = get_float_resource("grabWindowDelay", "Seconds"); if (unmap <= 0.00001 || unmap > 20) unmap = 0.66; } unmap_time = unmap * 100000; } #ifdef DEBUG fprintf(stderr, "\n%s: window 0x%08lX root: %d saver: %d grab: %d wait: %.1f\n", progname, (unsigned long) window, root_p, saver_p, grab_mouse_p, ((double)unmap_time)/1000000.0); { XWindowAttributes xgwa2; XGetWindowAttributes (dpy, window, &xgwa2); fprintf(stderr, "%s: ", progname); describe_visual(stderr, screen, xgwa2.visual, ####); fprintf (stderr, "\n"); } #endif /* DEBUG */ if (!root_p) XSetWindowBackgroundPixmap (dpy, window, None); if (grab_mouse_p) { /* prevent random viewer of the screen saver (locker) from messing with windows. We don't check whether it succeeded, because what are our options, really... */ XGrabPointer (dpy, real_root, True, ButtonPressMask|ButtonReleaseMask, GrabModeAsync, GrabModeAsync, None, None, CurrentTime); XGrabKeyboard (dpy, real_root, True, GrabModeSync, GrabModeAsync, CurrentTime); } if (unmap_time > 0) { XUnmapWindow (dpy, window); install_screen_colormaps (screen); XSync (dpy, True); usleep(unmap_time); /* wait for everyone to swap in and handle exposes */ } XGetWindowAttributes (dpy, window, &xgwa); if (!root_p) { #ifdef HAVE_READ_DISPLAY_EXTENSION if (! read_display(screen, window, 0, saver_p)) #endif /* HAVE_READ_DISPLAY_EXTENSION */ { #if defined(HAVE_READ_DISPLAY_EXTENSION) && defined(DEBUG) fprintf(stderr, "%s: read_display() failed\n", progname); #endif /* DEBUG */ copy_default_colormap_contents (screen, xgwa.colormap, xgwa.visual); raise_window(dpy, window, saver_p); } } else /* root_p */ { Pixmap pixmap; XWindowAttributes xgwa; XGetWindowAttributes(dpy, window, &xgwa); pixmap = XCreatePixmap(dpy, window, xgwa.width, xgwa.height, xgwa.depth); #ifdef HAVE_READ_DISPLAY_EXTENSION if (! read_display(screen, window, pixmap, True)) #endif { Window real_root = XRootWindowOfScreen (xgwa.screen); /* not vroot */ XGCValues gcv; GC gc; #if defined(HAVE_READ_DISPLAY_EXTENSION) && defined(DEBUG) fprintf(stderr, "%s: read_display() failed\n", progname); #endif /* DEBUG */ copy_default_colormap_contents (screen, xgwa.colormap, xgwa.visual); gcv.function = GXcopy; gcv.subwindow_mode = IncludeInferiors; gc = XCreateGC (dpy, window, GCFunction | GCSubwindowMode, &gcv); XCopyArea (dpy, real_root, pixmap, gc, xgwa.x, xgwa.y, xgwa.width, xgwa.height, 0, 0); XFreeGC (dpy, gc); } XSetWindowBackgroundPixmap (dpy, window, pixmap); XFreePixmap (dpy, pixmap); } if (grab_mouse_p) { XUngrabPointer (dpy, CurrentTime); XUngrabKeyboard (dpy, CurrentTime); } XSync (dpy, True); } void grab_screen_image (Screen *screen, Window window) { #ifdef HAVE_SGI_VIDEO char c, *s = get_string_resource("grabVideoProbability", "Float"); double prob = -1; if (!s || (1 != sscanf (s, " %lf %c", &prob, &c)) || prob < 0 || prob > 1) prob = 0.5; if ((random() % 100) < ((int) (100 * prob))) { XWindowAttributes xgwa; Display *dpy = DisplayOfScreen (screen); XGetWindowAttributes (dpy, window, &xgwa); # ifdef DEBUG fprintf(stderr, "%s: trying to grab from video...\n", progname); # endif /* DEBUG */ if (grab_video_frame (screen, xgwa.visual, window)) { if (xgwa.depth < 24) { int class = visual_class (screen, xgwa.visual); if (class == PseudoColor || class == DirectColor) make_cubic_colormap (screen, window, xgwa.visual); } return; } } #endif /* HAVE_SGI_VIDEO */ grab_screen_image_1 (screen, window); } /* When we are grabbing and manipulating a screen image, it's important that we use the same colormap it originally had. So, if the screensaver was started with -install, we need to copy the contents of the default colormap into the screensaver's colormap. */ static void copy_default_colormap_contents (Screen *screen, Colormap to_cmap, Visual *to_visual) { Display *dpy = DisplayOfScreen (screen); Visual *from_visual = DefaultVisualOfScreen (screen); Colormap from_cmap = XDefaultColormapOfScreen (screen); XColor *old_colors, *new_colors; unsigned long *pixels; XVisualInfo vi_in, *vi_out; int out_count; int from_cells, to_cells, max_cells, got_cells; int i; if (from_cmap == to_cmap) return; vi_in.screen = XScreenNumberOfScreen (screen); vi_in.visualid = XVisualIDFromVisual (from_visual); vi_out = XGetVisualInfo (dpy, VisualScreenMask|VisualIDMask, &vi_in, &out_count); if (! vi_out) abort (); from_cells = vi_out [0].colormap_size; XFree ((char *) vi_out); vi_in.screen = XScreenNumberOfScreen (screen); vi_in.visualid = XVisualIDFromVisual (to_visual); vi_out = XGetVisualInfo (dpy, VisualScreenMask|VisualIDMask, &vi_in, &out_count); if (! vi_out) abort (); to_cells = vi_out [0].colormap_size; XFree ((char *) vi_out); max_cells = (from_cells > to_cells ? to_cells : from_cells); old_colors = (XColor *) calloc (sizeof (XColor), max_cells); new_colors = (XColor *) calloc (sizeof (XColor), max_cells); pixels = (unsigned long *) calloc (sizeof (unsigned long), max_cells); for (i = 0; i < max_cells; i++) old_colors[i].pixel = i; XQueryColors (dpy, from_cmap, old_colors, max_cells); got_cells = max_cells; allocate_writable_colors (dpy, to_cmap, pixels, &got_cells); #ifdef DEBUG if (got_cells != max_cells) fprintf(stderr, "%s: got only %d of %d cells\n", progname, got_cells, max_cells); #endif /* DEBUG */ if (got_cells <= 0) /* we're screwed */ ; else if (got_cells == max_cells && /* we're golden */ from_cells == to_cells) XStoreColors (dpy, to_cmap, old_colors, got_cells); else /* try to cope... */ { for (i = 0; i < got_cells; i++) { XColor *c = old_colors + i; int j; for (j = 0; j < got_cells; j++) if (pixels[j] == c->pixel) { /* only store this color value if this is one of the pixels we were able to allocate. */ XStoreColors (dpy, to_cmap, c, 1); break; } } } #ifdef DEBUG fprintf(stderr, "%s: installing copy of default colormap\n", progname); #endif /* DEBUG */ free (old_colors); free (new_colors); free (pixels); } /* The SGI ReadDisplay extension. This extension lets you get back a 24-bit image of the screen, taking into account the colors with which all windows are *currently* displayed, even if those windows have different visuals. Without this extension, presence of windows with different visuals or colormaps will result in technicolor when one tries to grab the screen image. */ #ifdef HAVE_READ_DISPLAY_EXTENSION static Bool read_display (Screen *screen, Window window, Pixmap into_pixmap, Bool dont_wait) { Display *dpy = DisplayOfScreen (screen); XWindowAttributes xgwa; int rd_event_base = 0; int rd_error_base = 0; unsigned long hints = 0; XImage *image = 0; XGCValues gcv; int class; GC gc; Bool install_p = False; /* Check to see if the server supports the extension, and bug out if not. */ if (! XReadDisplayQueryExtension (dpy, &rd_event_base, &rd_error_base)) return False; /* If this isn't a visual we know how to handle, bug out. We handle: = TrueColor in depths 8, 12, 16, and 32; = PseudoColor and DirectColor in depths 8 and 12. */ XGetWindowAttributes(dpy, window, &xgwa); class = visual_class (screen, xgwa.visual); if (class == TrueColor) { if (xgwa.depth != 8 && xgwa.depth != 12 && xgwa.depth != 16 && xgwa.depth != 24 && xgwa.depth != 32) return False; } else if (class == PseudoColor || class == DirectColor) { if (xgwa.depth != 8 && xgwa.depth != 12) return False; else /* Install a colormap that makes this visual behave like a TrueColor visual of the same depth. */ install_p = True; } /* Try and read the screen. */ hints = (XRD_TRANSPARENT | XRD_READ_POINTER); image = XReadDisplay (dpy, window, xgwa.x, xgwa.y, xgwa.width, xgwa.height, hints, &hints); if (!image) return False; if (!image->data) { XDestroyImage(image); return False; } /* XReadDisplay tends to LIE about the depth of the image it read. It is returning an XImage which has `depth' and `bits_per_pixel' confused! That is, on a 24-bit display, where all visuals claim depth 24, and where XGetImage would return an XImage with depth 24, and where XPutImage will get a BadMatch with images that are not depth 24, XReadDisplay is returning images with depth 32! Fuckwits! So if the visual is of depth 24, but the image came back as depth 32, hack it to be 24 lest we get a BadMatch from XPutImage. I wonder what happens on an 8-bit SGI... Probably it still returns an image claiming depth 32? Certainly it can't be 8. So, let's just smash it to 32... */ if (image->depth == 32 /* && xgwa.depth == 24 */ ) image->depth = 24; /* If the visual of the window/pixmap into which we're going to draw is less deep than the screen itself, then we need to convert the grabbed bits to match the depth by clipping off the less significant bit-planes of each color component. */ if (image->depth > xgwa.depth) { int x, y; /* We use the same image->data in both images -- that's ok, because since we're reading from B and writing to A, and B uses more bytes per pixel than A, the write pointer won't overrun the read pointer. */ XImage *image2 = XCreateImage (dpy, xgwa.visual, xgwa.depth, ZPixmap, 0, image->data, xgwa.width, xgwa.height, 8, 0); if (!image2) return False; #ifdef DEBUG fprintf(stderr, "%s: converting from depth %d to depth %d\n", progname, image->depth, xgwa.depth); #endif /* DEBUG */ for (y = 0; y < image->height; y++) for (x = 0; x < image->width; x++) { /* #### really these shift values should be determined from the mask values -- but that's a pain in the ass, and anyway, this is an SGI-specific extension so hardcoding assumptions about the SGI server's behavior isn't *too* heinous... */ unsigned long pixel = XGetPixel(image, x, y); unsigned int r = (pixel & image->red_mask); unsigned int g = (pixel & image->green_mask) >> 8; unsigned int b = (pixel & image->blue_mask) >> 16; if (xgwa.depth == 8) pixel = ((r >> 5) | ((g >> 5) << 3) | ((b >> 6) << 6)); else if (xgwa.depth == 12) pixel = ((r >> 4) | ((g >> 4) << 4) | ((b >> 4) << 8)); else if (xgwa.depth == 16) pixel = ((r >> 3) | ((g >> 3) << 5) | ((b >> 3) << 10)); else abort(); XPutPixel(image2, x, y, pixel); } image->data = 0; XDestroyImage(image); image = image2; } /* Now actually put the bits into the window or pixmap -- note the design bogosity of this extension, where we've been forced to take 24 bit data from the server to the client, and then push it back from the client to the server, *without alteration*. We should have just been able to tell the server, "put a screen image in this drawable", instead of having to go through the intermediate step of converting it to an Image. Geez. (Assuming that the window is of screen depth; we happen to handle less deep windows, but that's beside the point.) */ gcv.function = GXcopy; gc = XCreateGC (dpy, window, GCFunction, &gcv); if (into_pixmap) { gcv.function = GXcopy; gc = XCreateGC (dpy, into_pixmap, GCFunction, &gcv); XPutImage (dpy, into_pixmap, gc, image, 0, 0, 0, 0, xgwa.width, xgwa.height); } else { gcv.function = GXcopy; gc = XCreateGC (dpy, window, GCFunction, &gcv); /* Ok, now we'll be needing that window on the screen... */ raise_window(dpy, window, dont_wait); /* Plop down the bits... */ XPutImage (dpy, window, gc, image, 0, 0, 0, 0, xgwa.width, xgwa.height); } XFreeGC (dpy, gc); if (image->data) { free(image->data); image->data = 0; } XDestroyImage(image); if (install_p) make_cubic_colormap (screen, window, xgwa.visual); return True; } #endif /* HAVE_READ_DISPLAY_EXTENSION */ #if defined(HAVE_READ_DISPLAY_EXTENSION) || defined(HAVE_SGI_VIDEO) /* Makes and installs a colormap that makes a PseudoColor or DirectColor visual behave like a TrueColor visual of the same depth. */ static void make_cubic_colormap (Screen *screen, Window window, Visual *visual) { Display *dpy = DisplayOfScreen (screen); Colormap cmap = XCreateColormap(dpy, window, visual, AllocAll); int nr, ng, nb, cells; int r, g, b; int depth; XColor colors[4097]; int i; depth = visual_depth(screen, visual); switch (depth) { case 8: nr = 3; ng = 3; nb = 2; cells = 256; break; case 12: nr = 4; ng = 4; nb = 4; cells = 4096; break; default: abort(); break; } memset(colors, 0, sizeof(colors)); for (i = 0; i < cells; i++) { colors[i].flags = DoRed|DoGreen|DoBlue; colors[i].red = colors[i].green = colors[i].blue = 0; } for (r = 0; r < (1 << nr); r++) for (g = 0; g < (1 << ng); g++) for (b = 0; b < (1 << nb); b++) { i = (r | (g << nr) | (b << (nr + ng))); colors[i].pixel = i; if (depth == 8) { colors[i].red = ((r << 13) | (r << 10) | (r << 7) | (r << 4) | (r << 1)); colors[i].green = ((g << 13) | (g << 10) | (g << 7) | (g << 4) | (g << 1)); colors[i].blue = ((b << 14) | (b << 12) | (b << 10) | (b << 8) | (b << 6) | (b << 4) | (b << 2) | b); } else { colors[i].red = (r << 12) | (r << 8) | (r << 4) | r; colors[i].green = (g << 12) | (g << 8) | (g << 4) | g; colors[i].blue = (b << 12) | (b << 8) | (b << 4) | b; } } #ifdef DEBUG fprintf(stderr, "%s: installing cubic colormap\n", progname); #endif /* DEBUG */ XStoreColors (dpy, cmap, colors, cells); XSetWindowColormap (dpy, window, cmap); /* Gag, install the colormap. This is definitely right in the `if xscreensaver_window_p' case, since it will never get installed otherwise. But, if we don't do it unconditionally, then the new colormap won't get installed until the window (re-)gains focus. It's generally very antisocial to install the colormap of a non-OverrideRedirect window (that task belongs to the WM) and if we were being kosher, we would only install this cmap if the old cmap was already installed (or perhaps, if the window had focus.) But, since this extension only exists on SGIs, and since SGIs can handle four colormaps at once, let's go ahead and install it all the time, so that even if the window pops up and has never had focus, it will still display in the proper colors. */ XInstallColormap (dpy, cmap); } #endif /* HAVE_READ_DISPLAY_EXTENSION || HAVE_SGI_VIDEO */