http://packetstormsecurity.org/UNIX/admin/xscreensaver-4.14.tar.gz

[xscreensaver] / hacks / distort.c

diff --git a/hacks/distort.c b/hacks/distort.c
index 4218418f201628b8b54c2969a506736196883d0e..54a12fa9d3e6623a10ff7bf91f914f31b47c4605 100644 (file)
--- a/hacks/distort.c
+++ b/hacks/distort.c
@@ -1,5 +1,5 @@
 /* -*- mode: C; tab-width: 4 -*-
- * xscreensaver, Copyright (c) 1992, 1993, 1994, 1996, 1997, 1998
+ * xscreensaver, Copyright (c) 1992, 1993, 1994, 1996, 1997, 1998, 2002, 2003
  * Jamie Zawinski <jwz@jwz.org>
  *
  * Permission to use, copy, modify, distribute, and sell this software and its
@@ -113,6 +113,8 @@ static void init_distort(Display *dpy, Window window)
        if (get_boolean_resource("bounce", "Boolean"))
                effect = &move_lense;
 
+       XGetWindowAttributes (dpy, window, &xgwa);
+
        if (effect == NULL && radius == 0 && speed == 0 && number == 0
                && !blackhole && !vortex && !magnify && !reflect) {
 /* if no cmdline options are given, randomly choose one of:
@@ -201,8 +203,23 @@ static void init_distort(Display *dpy, Window window)
                 abort(); break;
                }
 
+        /* but if the window is small, reduce default radius */
+        if (xgwa.width < radius * 8)
+          radius = xgwa.width/8;
        }
 
+    /* never allow the radius to be too close to the min window dimension
+     */
+    if (radius >= xgwa.width  * 0.45) radius = xgwa.width  * 0.45;
+    if (radius >= xgwa.height * 0.45) radius = xgwa.height * 0.45;
+
+
+    /* -swamp mode consumes vast amounts of memory, proportional to radius --
+       so throttle radius to a small-ish value (60 => ~30MB.)
+     */
+    if (effect == &swamp_thing && radius > 60)
+      radius = 60;
+
        if (delay < 0)
                delay = 0;
        if (radius <= 0)
@@ -222,7 +239,6 @@ static void init_distort(Display *dpy, Window window)
        if (draw == NULL)
                draw = &plain_draw;
 
-       XGetWindowAttributes (dpy, window, &xgwa);
        black_pixel = BlackPixelOfScreen( xgwa.screen );
 
        gcv.function = GXcopy;
@@ -232,7 +248,7 @@ static void init_distort(Display *dpy, Window window)
                gcflags |= GCSubwindowMode;
        gc = XCreateGC (dpy, window, gcflags, &gcv);
 
-       grab_screen_image (xgwa.screen, window);
+    load_random_image (xgwa.screen, window, window, NULL);
 
        buffer_map = 0;
        orig_map = XGetImage(dpy, window, 0, 0, xgwa.width, xgwa.height,
@@ -533,9 +549,9 @@ static void plain_draw(int k)
                XShmPutImage(g_dpy, g_window, gc, buffer_map, 0, 0, xy_coo[k].x, xy_coo[k].y,
                                2*radius+speed+2, 2*radius+speed+2, False);
        else
-# endif
 
        if (!use_shm)
+# endif
                XPutImage(g_dpy, g_window, gc, buffer_map, 0, 0, xy_coo[k].x, xy_coo[k].y,
                                2*radius+speed+2, 2*radius+speed+2);
 
@@ -564,6 +580,7 @@ static void reflect_draw(int k)
                ly = i - cy;
                lysq = ly * ly;
                ny = xy_coo[k].y + i;
+               if (ny >= orig_map->height) ny = orig_map->height-1;
                for(j = 0 ; j < 2*radius+speed+2 ; j++) {
                        lx = j - cx;
                        dist = lx * lx + lysq;