BGRABitmap tutorial

[chronozphere]

Thanks. How can I install that lpk package? Can I move my source files after I have installed the package? (Really annoying that I have to ask this, because all the documentation for lazarus is inaccessible. )

Update: It seems like they have fixed the problem.

[circular]

Once the package is installed, you need to specify package dependency in the project inspector. Then you can move your project whereever you want.

[chronozphere]

I have a little problem. I want to draw a closed polygon, but it doesn't work:

var
  image: TBGRABitmap;
  storedSpline: array of TPointF;
  c: TBGRAPixel;
begin
  image := TBGRABitmap.Create(ClientWidth,ClientHeight,ColorToBGRA(ColorToRGB(clBtnFace)));
  c := ColorToBGRA(ColorToRGB(clWindowText));

  setLength(storedSpline, 3);
  storedSpline[0].x := 50;
  storedSpline[0].y := 50;
  storedSpline[1].x := 100;
  storedSpline[1].y := 100;
  storedSpline[2].x := 0;
  storedSpline[2].y := 100;

  image.DrawPolylineAntialias(storedSpline,c,1, true); //This call should draw a closed spline

  image.Draw(Canvas,0,0,True);
  image.free;
end;

The last parameter is called Closed, so I presume that when I pass true, I will get a closed spline, but It's still open.
Anybody?

[circular]

It's normal. A polyline is not a closed figure. The closed parameter means that the end of the segment is closed. See here :
http://wiki.lazarus.freepascal.org/B...map_tutorial_6

If you want to draw a closed path, then use DrawPolygonAntialias.

By the way, naming a variable storedSpline does not automatically create a spline. You need to call ComputeClosedSpline. See here :
http://wiki.lazarus.freepascal.org/B...map_tutorial_7

If you feel the tutorial is ambiguous somewhere, please tell me what you suggest to add or change.

[chronozphere]

Thanks! It works great now.

By the way, naming a variable storedSpline does not automatically create a spline. You need to call ComputeClosedSpline. See here :

Don't pay attention to that name. I was reusing that name from another piece of code that did use a spline.

[circular]

Hello,

I've added a new tutorial about texture mapping :

http://wiki.lazarus.freepascal.org/B...ap_tutorial_10

Enjoy

[circular]

Hello people,

I've added comments to BGRABitmap source code, so it's easy to browse and hopefully to understand it.

You can have a look in the last zip file (3.7) :
https://sourceforge.net/projects/lazpaint/files/src/

If something is hard to understand, tell me so I'll add more comments.

By the way, LazPaint textures look better, and blur filter is faster (the fast blur is very fast indeed).