[Lazarus] TPicture beginupdate or similar

Leonardo M. Ramé l.rame at griensu.com
Fri Nov 26 20:15:34 CET 2010

On 2010-11-26 16:08:07 -0300, Leonardo M. Ramé wrote:
> Hi again, I'm doing some transformations on a TImage using
> Canvas.CopyRect and don't want to show intermediate steps before the final one is done, 
> I need to do something similar to TListView's Items.BeginUpdate - Items.EndUpdate.
> What I have is a big image on background, and in the OnMouseMove
> event I copy the area surrounding the mouse to a temporal bitmap, then
> draw over the original image on that area. When the user moves the mouse
> again, before doing anithing, I paint the original area with the
> temporary bitmap to obtain the original image, then re-draw on the new
> area. This causes flickering, and I thing it can be avoided using
> something like BeginUpdate at the beginning of my method and EndUpdate
> at the end.
> Any hint?.
> -- 
> Leonardo M. Ramé
> http://leonardorame.blogspot.com

Sorry, done with a temporal bitmap.

Leonardo M. Ramé

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