switch matrix colors

xscreensaver.patch

diff '--color=auto' -Naur xscreensaver-6.00/hacks/glx/glmatrix.c xscreensaver-6.00.patched/hacks/glx/glmatrix.c
--- xscreensaver-6.00/hacks/glx/glmatrix.c	2021-02-07 12:15:42.000000000 -0800
+++ xscreensaver-6.00.patched/hacks/glx/glmatrix.c	2021-05-02 17:21:54.254157186 -0700
@@ -213,6 +213,11 @@
   {&do_texture, "texture",    "Texture", DEF_TEXTURE,   t_Bool},
 };
 
+static unsigned char rgb_red = 0xFF;
+static unsigned char rgb_green = 0x00;
+static unsigned char rgb_blue = 0x00;
+static time_t last_color_switch = 0;
+
 ENTRYPOINT ModeSpecOpt matrix_opts = {countof(opts), opts, countof(vars), vars, NULL};
 
 
@@ -745,6 +750,10 @@
           }
     }
 
+  rgb_red = random() % 255;
+  rgb_green = random() % 255;
+  rgb_blue = random() % 255;
+
   /* The pixmap is a color image with no transparency.  Set the texture's
      alpha to be the green channel, and set the green channel to be 100%.
    */
@@ -769,7 +778,9 @@
           unsigned char g = (p >> gpos) & 0xFF;
           unsigned char b = (p >> bpos) & 0xFF;
           unsigned char a = g;
-          g = 0xFF;
+          r = rgb_red;
+          g = rgb_green;
+          b = rgb_blue;
           p = (r << rpos) | (g << gpos) | (b << bpos) | (a << apos);
           XPutPixel (xi, x, y, p);
         }
@@ -978,11 +989,17 @@
   matrix_configuration *mp = &mps[MI_SCREEN(mi)];
   Display *dpy = MI_DISPLAY(mi);
   Window window = MI_WINDOW(mi);
+  time_t now = time ((time_t *) 0);
   int i;
 
   if (!mp->glx_context)
     return;
 
+  if (now - last_color_switch > 15) {
+    load_textures (mi, 0);
+    last_color_switch = now;
+  }
+
   glXMakeCurrent(MI_DISPLAY(mi), MI_WINDOW(mi), *mp->glx_context);
 
   glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);