[Lazarus] Fast drawing to canvas

Sven Barth pascaldragon at googlemail.com
Fri Feb 10 11:13:30 CET 2012


Am 10.02.2012 10:58, schrieb Felipe Monteiro de Carvalho:
> On Fri, Feb 10, 2012 at 10:44 AM, Sven Barth
> <pascaldragon at googlemail.com>  wrote:
>> (maybe .Canvas.Pixel[...] access isn't that good for that
>> purpose ^^)
>
> One should basically almost never use Canvas.Pixels in LCL-Gtk2,
> unless you want to draw some points, because the image is located in
> the X server.
>
> Draw first to a TLazIntfImage and then convert it to a TBitmap.
>

Right... didn't thought of that... I'll try that today evening when I'm 
at home again (where I have the code).

But why does the canvas of a TGraphic descendant (TBitmap, 
TPortableNetworkGraphic, etc.) need to store the data on the X-Server? 
Wouldn't it be enough to transport that only when it's displayed?

Regards,
Sven




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