[lazarus] How to implement TCanvas.Pixel[x,y] functionality in 500 easy steps...

[Marc Weustink]

At 22:20 24-02-01 -0600, Shane Miller wrote:
>How to implement Canvas.Pixels..
>
>If you look at canvas.inc you will see that the function GetPixel already
>exists so I'm not sure that it needs to be "implemented".  Perhaps it simply
>needs to be debugged.  In getpixel there is a CNSendMessage call that sends
>a LM_GetPixel message and a MSG variable to gtkobject.inc.  The LM_GetPixel
>causes a call to GetPixel and in that function the PixColor of the
>TLMSetGetPixel should be set.

I don't know if we should use the LM_[G|S]etPixel messages here. IMO the 
messages don't have a long life if you ask me. It is a little strange if 
you look at all the other graphic functions we've implemented.

I think it would be nice if it is implemented through the API:

   function GetPixel(DC: HDC; X, Y: Integer): COLORREF; stdcall;
   function SetPixel(DC: HDC; X, Y: Integer; Color: COLORREF): COLORREF; 
stdcall;

You can add these through the ApiWizz tool. Then only the GTKWinApi.inc 
parts needs to be filled in.

Marc