Re: Double buffering and canvases.

Petasis Gewrgios (
Thu, 5 Dec 1996 20:05:48 +0200 (WET)

To subscribers of the xforms list from Petasis Gewrgios <> :

Steve Lamont wrote:
> It may be helpful to run your program in synchronous mode in order to
> localize the source of error (by default, XForms derived programs and
> most other X applications run in asynchronous mode, meaning that
> requests are batched up and sent in one great glob and responses are
> sent more or less in the same way, to minimize the number of round
> trips to the X server). You can put your application into synchronous
> mode by using the comand flag '-sync'.
> You might also try setting the debug level (with '-debug N', where 'N'
> is the debug level) to see if that tells you anything.
I tried -sync and i get (among thousants of screens!) :

MainLoopUser Event(7,w=0x2400016 s=1032) EnterNotify Mode Normal
In EventCallback [events.c 37] Unknown window=0x2400016
Ignored Event(7,w=0x2400016 s=1032) EnterNotify Mode Normal
PutbackEvent Event(7,w=40390x2400016 s=1032) EnterNotify Mode Normal
X Error of failed request: BadWindow (invalid Window parameter)
Major opcode of failed request: 10 (X_UnmapWindow)
Resource id in failed request: 0x2400038
Serial number of failed request: 14038
Current serial number in output stream: 1

Anyone understanding anything ????
Also, the first time i allocate the colors i get :
In fl_mapcolor [flcolor.c 760] mapping 1006 (20,19,19)
In XFreeColor [flcolor.c 1126] bad pixel
for all the colors i allocate. This message is because forms free the colors >
FL_FREE_COL1 or should i start worring about ?????
(If i use fl_set_dblbufer( form, 0) program runs ok.The first time i allocate
colors i get this "bad pixel". All other times i reallocate colors i get it
only once and a while..)
About the fl_deactivate_form, although i have used it, i get messages about
mouse moves, mouse clicks, while drawing in the free object. Does these
functions (activate,deactivate) produce a message that i should see???
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