http://ftp.x.org/contrib/applications/xscreensaver-2.23.tar.gz

[xscreensaver] / hacks / helix.c

diff --git a/hacks/helix.c b/hacks/helix.c
index 758c5557e1a7ef1d57cf44688603a088753576cc..97de40dc7fb360ddd50a89b3ba5aba9659bb2a46 100644 (file)
--- a/hacks/helix.c
+++ b/hacks/helix.c
@@ -12,19 +12,23 @@
 
 /* Algorithm from a Mac program by Chris Tate, written in 1988 or so. */
 
-/* 10-May-97: merged ellipse code by Dan Stromberg <strombrg@nis.acs.uci.edu>
+/* 18-Sep-97: Johannes Keukelaar (johannes@nada.kth.se): Improved screen
+ *            eraser.
+ * 10-May-97: merged ellipse code by Dan Stromberg <strombrg@nis.acs.uci.edu>
  *            as found in xlockmore 4.03a10.
  * 1992:      jwz created.
  */
 
 #include <math.h>
 #include "screenhack.h"
+#include "erase.h"
 
 static double sins [360];
 static double coss [360];
 
-static GC draw_gc, erase_gc;
+static GC draw_gc;
 static unsigned int default_fg_pixel;
+static int sleep_time;
 
 static void
 init_helix (Display *dpy, Window window)
@@ -39,7 +43,6 @@ init_helix (Display *dpy, Window window)
     get_pixel_resource ("foreground", "Foreground", dpy, cmap);
   draw_gc = XCreateGC (dpy, window, GCForeground, &gcv);
   gcv.foreground = get_pixel_resource ("background", "Background", dpy, cmap);
-  erase_gc = XCreateGC (dpy, window, GCForeground, &gcv);
 
   for (i = 0; i < 360; i++)
     {
@@ -250,7 +253,6 @@ random_trig (Display *dpy, Window window, XColor *color, Bool *got_color)
 static void
 random_helix_or_trig (Display *dpy, Window window)
 {
-  int i;
   Bool free_color = False;
   XColor color;
   int width, height;
@@ -267,17 +269,10 @@ random_helix_or_trig (Display *dpy, Window window)
     random_trig(dpy, window, &color, &free_color);
 
   XSync (dpy, True);
-  sleep (5);
+  sleep ( sleep_time );
+
+  erase_full_window(dpy, window);
 
-  for (i = 0; i < height; i++)
-    {
-      int y = (random () % height);
-      XDrawLine (dpy, window, erase_gc, 0, y, width, y);
-      XFlush (dpy);
-      if ((i % 50) == 0)
-       usleep (10000);
-    }
-  XClearWindow (dpy, window);
   if (free_color) XFreeColors (dpy, cmap, &color.pixel, 1, 0);
   XSync (dpy, True);
   sleep (1);
@@ -287,15 +282,21 @@ random_helix_or_trig (Display *dpy, Window window)
 char *progclass = "Helix";
 
 char *defaults [] = {
-  "Helix.background: black",           /* to placate SGI */
+  ".background: black",
+  "*delay:      5",
   0
 };
 
-XrmOptionDescRec options [] = { { 0, } };
+XrmOptionDescRec options [] = {   
+  { "-delay",           ".delay",               XrmoptionSepArg, 0 },
+  { 0 },
+};
+int options_size = (sizeof (options) / sizeof (options[0]));
 
 void
 screenhack (Display *dpy, Window window)
 {
+  sleep_time = get_integer_resource("delay", "Integer");
   init_helix (dpy, window);
   while (1)
     random_helix_or_trig (dpy, window);