1 files changed, 71 insertions, 0 deletions
diff --git a/lib/gs/examples/ball.erl b/lib/gs/examples/ball.erl
new file mode 100644
index 0000000000..3f91a7b379
--- /dev/null
+++ b/lib/gs/examples/ball.erl
@@ -0,0 +1,71 @@
+%%
+%% %CopyrightBegin%
+%% 
+%% Copyright Ericsson AB 1996-2009. All Rights Reserved.
+%% 
+%% The contents of this file are subject to the Erlang Public License,
+%% Version 1.1, (the "License"); you may not use this file except in
+%% compliance with the License. You should have received a copy of the
+%% Erlang Public License along with this software. If not, it can be
+%% retrieved online at http://www.erlang.org/.
+%% 
+%% Software distributed under the License is distributed on an "AS IS"
+%% basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+%% the License for the specific language governing rights and limitations
+%% under the License.
+%% 
+%% %CopyrightEnd%
+%%
+
+%%
+%% ------------------------------------------------------------
+%% A simple demo showing a ball
+%% bouncing in a window.
+%% ------------------------------------------------------------
+
+-module(ball).
+
+-export([start/0,init/0]).
+
+start() ->
+    spawn(ball,init,[]).
+
+init() ->
+    I= gs:start(),
+    W= gs:window(I,[{title,"Ball"},{width,300},{height,300},{map,true}]),
+    C= gs:canvas(W,[{width,300},{height,300},{bg,yellow}]),
+    gs:button(W,[{label, {text,"Quit Demo"}},{x,100}]),
+    Ball = gs:oval(C,[{coords,[{0,0},{50,50}]},{fill,red}]),
+    ball(Ball,0,0,5.5,4.1).
+
+ball(Ball,X,Y,DX,DY) ->
+    {NX,NDX} = cc(X,DX),
+    {NY,NDY} = cc(Y,DY),
+    gs:config(Ball,{move,{DX,DY}}),    
+    receive
+	{gs,_,click,_,_} -> exit(normal);
+	{gs,_,destroy,_,_} -> exit(normal)
+    after 20 ->
+	    true
+    end,
+    ball(Ball,NX,NY,NDX,NDY).
+
+cc(X,DX) ->
+    if 
+	DX>0 ->
+	    if 
+		X=<250 ->
+		    {X+DX,DX};
+		x>250 ->
+		    {X-DX,-DX}
+	    end;
+	DX<0 ->
+	    if
+		X>=0 ->
+		    {X+DX,DX};
+		X<0 ->
+		    {X-DX,-DX}
+	    end
+    end.
+
+%% ------------------------------------------------------------