--- /dev/null
+/* xscreensaver, Copyright (c) 1992, 1993, 1994, 1997, 1998
+ * Jamie Zawinski <jwz@jwz.org>
+ *
+ * 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 <stdio.h>
+#include <unistd.h>
+#include <stdlib.h>
+#include <string.h>
+#include <X11/Xatom.h>
+#include <X11/Xutil.h>
+
+#ifdef HAVE_XMU
+# ifndef VMS
+# include <X11/Xmu/WinUtil.h>
+# else /* VMS */
+# include <Xmu/WinUtil.h>
+# endif /* VMS */
+#endif
+
+#include "grabscreen.h"
+
+#include "vroot.h"
+#undef RootWindowOfScreen
+#undef RootWindow
+#undef DefaultRootWindow
+
+
+#ifdef HAVE_READ_DISPLAY_EXTENSION
+# include <X11/extensions/readdisplay.h>
+ static Bool read_display (Screen *, Window, Pixmap, Bool);
+#endif /* HAVE_READ_DISPLAY_EXTENSION */
+
+
+static void copy_default_colormap_contents (Screen *, Colormap, Visual *);
+
+#ifdef HAVE_READ_DISPLAY_EXTENSION
+static void allocate_cubic_colormap (Screen *, Window, Visual *);
+void remap_image (Screen *, Window, Colormap, XImage *);
+#endif
+
+
+static Bool
+MapNotify_event_p (Display *dpy, XEvent *event, XPointer window)
+{
+ return (event->xany.type == MapNotify &&
+ event->xvisibility.window == (Window) window);
+}
+
+
+void
+grabscreen_verbose(void)
+{
+}
+
+
+static void
+raise_window(Display *dpy, Window window, Bool dont_wait)
+{
+
+ 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);
+
+ XSelectInput (dpy, window, (xgwa.your_event_mask | StructureNotifyMask));
+ }
+
+ 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;
+}
+
+
+
+/* Whether the given window is:
+ - the real root window;
+ - the virtual root window;
+ - a direct child of the root window;
+ - a direct child of the window manager's decorations.
+ */
+Bool
+top_level_window_p (Screen *screen, Window window)
+{
+ Display *dpy = DisplayOfScreen (screen);
+ Window root, parent, *kids;
+ Window vroot = VirtualRootWindowOfScreen(screen);
+ unsigned int nkids;
+
+ if (window == vroot)
+ return True;
+
+ if (!XQueryTree (dpy, window, &root, &parent, &kids, &nkids))
+ return False;
+
+ if (window == root)
+ return True;
+
+ /* If our direct parent is the root (or *a* root), then yes. */
+ if (parent == root || parent == vroot)
+ return True;
+ else
+ {
+ Atom type = None;
+ int format;
+ unsigned long nitems, bytesafter;
+ unsigned char *data;
+
+ /* If our direct parent has the WM_STATE property, then it is a
+ window manager decoration -- yes.
+ */
+ if (XGetWindowProperty (dpy, window,
+ XInternAtom (dpy, "WM_STATE", True),
+ 0, 0, False, AnyPropertyType,
+ &type, &format, &nitems, &bytesafter,
+ (unsigned char **) &data)
+ == Success
+ && type != None)
+ return True;
+ }
+
+ /* Else, no. We're deep in a tree somewhere.
+ */
+ 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);
+}
+
+
+void
+grab_screen_image (Screen *screen, Window window)
+{
+ Display *dpy = DisplayOfScreen (screen);
+ XWindowAttributes xgwa;
+ Window real_root;
+ Bool root_p;
+ Bool saver_p;
+ Bool grab_mouse_p = False;
+ int unmap_time = 0;
+
+ real_root = XRootWindowOfScreen (screen); /* not vroot */
+ root_p = (window == real_root);
+ saver_p = xscreensaver_window_p (dpy, window);
+
+ XGetWindowAttributes (dpy, window, &xgwa);
+ screen = xgwa.screen;
+
+ 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 = 2.5;
+ }
+ else
+ {
+ unmap = 0.66;
+ }
+ unmap_time = unmap * 100000;
+ }
+
+
+
+ if (!root_p && !top_level_window_p (screen, window))
+ {
+ return;
+ }
+
+
+ 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 */
+ }
+
+ if (!root_p)
+ {
+#ifdef HAVE_READ_DISPLAY_EXTENSION
+ if (! read_display(screen, window, 0, saver_p))
+#endif /* HAVE_READ_DISPLAY_EXTENSION */
+ {
+
+ // copy_default_colormap_contents (screen, xgwa.colormap, xgwa.visual);
+ raise_window(dpy, window, saver_p);
+
+ /* Generally it's bad news to call XInstallColormap() explicitly,
+ but this file does a lot of sleazy stuff already... This is to
+ make sure that the window's colormap is installed, even in the
+ case where the window is OverrideRedirect. */
+ if (xgwa.colormap) XInstallColormap (dpy, xgwa.colormap);
+ XSync (dpy, False);
+ }
+ }
+ else /* root_p */
+ {
+ Pixmap pixmap;
+ 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 (screen); /* not vroot */
+ XGCValues gcv;
+ GC gc;
+
+ 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);
+}
+
+
+/* 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);
+
+
+ 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;
+ }
+ }
+ }
+
+
+
+ free (old_colors);
+ free (new_colors);
+ free (pixels);
+}
+
+
+\f
+/* 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 remap_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, 15, 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 != 15 &&
+ 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
+ /* Allocate a TrueColor-like spread of colors for the image. */
+ remap_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;
+ }
+
+
+ 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 || xgwa.depth == 15)
+ /* Gah! I don't understand why these are in the other order. */
+ pixel = (((r >> 3) << 10) | ((g >> 3) << 5) | ((b >> 3)));
+ else
+ abort();
+
+ XPutPixel(image2, x, y, pixel);
+ }
+ image->data = 0;
+ XDestroyImage(image);
+ image = image2;
+ }
+
+ if (remap_p)
+ {
+ allocate_cubic_colormap (screen, window, xgwa.visual);
+ remap_image (screen, window, xgwa.colormap, image);
+ }
+
+ /* 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);
+
+ return True;
+}
+#endif /* HAVE_READ_DISPLAY_EXTENSION */
+
+
+#ifdef HAVE_READ_DISPLAY_EXTENSION
+
+/* Makes and installs a colormap that makes a PseudoColor or DirectColor
+ visual behave like a TrueColor visual of the same depth.
+ */
+static void
+allocate_cubic_colormap (Screen *screen, Window window, Visual *visual)
+{
+ Display *dpy = DisplayOfScreen (screen);
+ XWindowAttributes xgwa;
+ Colormap cmap;
+ int nr, ng, nb, cells;
+ int r, g, b;
+ int depth;
+ XColor colors[4097];
+ int i;
+
+ XGetWindowAttributes (dpy, window, &xgwa);
+ cmap = xgwa.colormap;
+ 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 (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;
+ colors[i].flags = DoRed|DoGreen|DoBlue;
+ 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;
+ }
+ }
+
+ {
+ int j;
+ int allocated = 0;
+ int interleave = cells / 8; /* skip around, rather than allocating in
+ order, so that we get better coverage if
+ we can't allocated all of them. */
+ for (j = 0; j < interleave; j++)
+ for (i = 0; i < cells; i += interleave)
+ if (XAllocColor (dpy, cmap, &colors[i + j]))
+ allocated++;
+
+ }
+}
+
+static unsigned long
+find_closest_pixel (XColor *colors, int ncolors,
+ unsigned long r, unsigned long g, unsigned long b)
+{
+ unsigned long distance = ~0;
+ int i, found = 0;
+
+ if (ncolors == 0)
+ abort();
+ for (i = 0; i < ncolors; i++)
+ {
+ unsigned long d;
+ int rd, gd, bd;
+
+ rd = r - colors[i].red;
+ gd = g - colors[i].green;
+ bd = b - colors[i].blue;
+ if (rd < 0) rd = -rd;
+ if (gd < 0) gd = -gd;
+ if (bd < 0) bd = -bd;
+ d = (rd << 1) + (gd << 2) + bd;
+
+ if (d < distance)
+ {
+ distance = d;
+ found = i;
+ if (distance == 0)
+ break;
+ }
+ }
+
+ return found;
+}
+
+
+void
+remap_image (Screen *screen, Window window, Colormap cmap, XImage *image)
+{
+ Display *dpy = DisplayOfScreen (screen);
+ unsigned long map[4097];
+ int x, y, i;
+ int cells;
+ XColor colors[4097];
+
+ if (image->depth == 8)
+ cells = 256;
+ else if (image->depth == 12)
+ cells = 4096;
+ else
+ abort();
+
+ memset(map, -1, sizeof(*map));
+ memset(colors, -1, sizeof(*colors));
+
+ for (i = 0; i < cells; i++)
+ colors[i].pixel = i;
+ XQueryColors (dpy, cmap, colors, cells);
+
+
+ for (i = 0; i < cells; i++)
+ {
+ unsigned short r, g, b;
+
+ if (cells == 256)
+ {
+ /* "RRR GGG BB" In an 8 bit map. Convert that to
+ "RRR RRR RR" "GGG GGG GG" "BB BB BB BB" to give
+ an even spread. */
+ r = (i & 0x07);
+ g = (i & 0x38) >> 3;
+ b = (i & 0xC0) >> 6;
+
+ r = ((r << 13) | (r << 10) | (r << 7) | (r << 4) | (r << 1));
+ g = ((g << 13) | (g << 10) | (g << 7) | (g << 4) | (g << 1));
+ b = ((b << 14) | (b << 12) | (b << 10) | (b << 8) |
+ (b << 6) | (b << 4) | (b << 2) | b);
+ }
+ else
+ {
+ /* "RRRR GGGG BBBB" In a 12 bit map. Convert that to
+ "RRRR RRRR" "GGGG GGGG" "BBBB BBBB" to give an even
+ spread. */
+ r = (i & 0x00F);
+ g = (i & 0x0F0) >> 4;
+ b = (i & 0xF00) >> 8;
+
+ r = (r << 12) | (r << 8) | (r << 4) | r;
+ g = (g << 12) | (g << 8) | (g << 4) | g;
+ b = (b << 12) | (b << 8) | (b << 4) | b;
+ }
+
+ map[i] = find_closest_pixel (colors, cells, r, g, b);
+ }
+
+
+ for (y = 0; y < image->height; y++)
+ for (x = 0; x < image->width; x++)
+ {
+ unsigned long pixel = XGetPixel(image, x, y);
+ if (pixel >= cells) abort();
+ XPutPixel(image, x, y, map[pixel]);
+ }
+}
+
+
+#endif /* HAVE_READ_DISPLAY_EXTENSION */
projects / shermanaquarium / blobdiff