[fpc-devel] TFPCustomCanvas Expanded Clipping

Felipe Monteiro de Carvalho felipemonteiro.carvalho at gmail.com
Thu Dec 8 09:14:01 CET 2011

Some more changes I'd like to propose. It seams that Rectangle is not
TCanvas compatible:

procedure TFPPixelCanvas.DoRectangle (const Bounds:TRect);

A rectangle over (0, 0, 10, 10) should not include the pixels line
with x=10 and y=10 but instead go only to x=9 and y=9, it is
considered that the position is in the top-left of the pixel

DoLine should not include the last point of the line (maybe unless you
have a pen cap), although this one is a bit confusing. But it is how
TCanvas works.

On Wed, Dec 7, 2011 at 2:43 PM, Hans-Peter Diettrich
<DrDiettrich1 at aol.com> wrote:
>> Things in practice are much more complex then one might initially
>> imagine. My regions implementation is reused for several things:
>> 1> Drawing clipping
>> 2> Drawing complex objects like poligons, polybeziers, arbitrary regions
>> 3> To clip mouse/touch events

There are more uses too:

4> Implement TRegion in LCL-CustomDrawn
5> Describe the shape of controls and forms

Felipe Monteiro de Carvalho

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