diff --git a/ueforth/common/extra_opcodes.h b/ueforth/common/extra_opcodes.h
index 52f2d3f..831fcb6 100644
--- a/ueforth/common/extra_opcodes.h
+++ b/ueforth/common/extra_opcodes.h
@@ -89,5 +89,8 @@
   XV(internals, "'argc", ARGC, DUP; tos = (cell_t) &g_sys.argc) \
   XV(internals, "'argv", ARGV, DUP; tos = (cell_t) &g_sys.argv) \
   XV(internals, "'runner", RUNNER, DUP; tos = (cell_t) &g_sys.runner) \
+  YV(internals, fill32, cell_t c = tos; DROP; cell_t n = tos; DROP; \
+                        uint32_t *a = (uint32_t *) tos; DROP; \
+                        for (;n;--n) *a++ = c) \
   Y(context, DUP; tos = (cell_t) (g_sys.context + 1)) \
   Y(latestxt, DUP; tos = (cell_t) g_sys.latestxt)
diff --git a/ueforth/common/grf_utils.fs b/ueforth/common/grf_utils.fs
index 8a8d64b..b3880db 100644
--- a/ueforth/common/grf_utils.fs
+++ b/ueforth/common/grf_utils.fs
@@ -18,6 +18,7 @@
 \ Drawing:
 \   box ( x y w h -- )
 
+also internals
 grf definitions
 
 0 value color
@@ -25,7 +26,8 @@ grf definitions
 internals definitions
 
 : hline { x y w }
-  x y pixel w 1- for color over l! 4 + next drop ;
+  \ x y pixel w 1- for color over l! 4 + next drop ;
+  x y pixel w color fill32 ;
 
 grf definitions also internals
 
diff --git a/ueforth/examples/heart_game.fs b/ueforth/examples/heart_game.fs
index 2c63631..7aed626 100755
--- a/ueforth/examples/heart_game.fs
+++ b/ueforth/examples/heart_game.fs
@@ -192,8 +192,12 @@ create arrow-table
   targeted-arrow
 ;
 
+0 value last-tm
+0 value next-tm
+
 : run
   begin
+    poll
     PRESSED event = if
       65 last-key = if
         init
@@ -202,11 +206,14 @@ create arrow-table
         fire
       then
     then
-    poll
-    100 random 0= if volcano-spew then
-    draw
-    tick
-    cleanup
+    event UNKNOWN = if
+      begin ms-ticks to next-tm next-tm last-tm - 10 < while 1 ms repeat
+      next-tm to last-tm
+      100 random 0= if volcano-spew then
+      draw
+      tick
+      cleanup
+    then
   FINISHED event = until
   bye
 ;