Graphics in Lazarus?
lazarus / 13-General

----------------------------------------------------------------------
Agent_AL · 2008-02-02 09:41

I need some graphic class that supports per-pixel drawing. It looks
like only tImage supports assigning values to pixels and has functions
like ellipse, line etc. But it's visual component and I need something
to be placed and edited only in memory, just like tBitmap from Delphi
(looks like it's not implemented in Lazarus and even doesn't have
Pixels property). I've tried creating TCanvas, tPicture, TLazIntfImage
and accessing pixels of each returns same error. TImage works much
slower, than TBitmap could (if it was implemented completely :?)
What do you use for basic imaging and storing images in memory?

----------------------------------------------------------------------
theo · 2008-02-02 11:07

Why do you think TBitmap is not implemented?

Code: [Select]procedure TForm1.Button1Click(Sender: TObject);
var bmp:TBitmap;
begin
bmp:=TBitmap.create;
bmp.Width:=100;
bmp.Height:=100;
bmp.Canvas.FillRect(Rect(0,0,100,100));
bmp.Canvas.Pixels[10,10]:=clred;
Image1.Picture.Bitmap.Assign(bmp);
bmp.free;
end;

----------------------------------------------------------------------
Agent_AL · 2008-02-02 11:22

I updated Lazarus from latest build two days ago (at least, I thoght
so  :shock: ).
TBitmap has reference to BITMAP, which is described in struct.inc
It has there:     
Code: [Select]  
     BITMAP = record
          bmType : LONG;
          bmWidth : LONG;
          bmHeight : LONG;
          bmWidthBytes : LONG;
          bmPlanes : WORD;
          bmBitsPixel : WORD;
          bmBits : LPVOID;
     end;

Okay, class constructor works and compiler doesn't say anything about
class.create line. However, it doesn't recognize other code lines.
Hmph, calling reference guide for TBITMAP from code I get
abovementioned lines, no properties/methods/constructors. I guess
something is screwed and Lazarus thinks everything is OK. I have
currently Laz+GLScene build installed, in about box I see 0.9.12 beta
label all time, no matter how often do I install freshly downloaded
files over current version and recompile Lazarus. It looks like I need
to reinstall completely everything.  :shock:

----------------------------------------------------------------------
Agent_AL · 2008-02-02 12:23

I just cannot express, how stupid I'm feeling now.  :oops:
Thanks for help. :wink:
I've just reinstalled Lazarus and suddenly realized that not just only
that case solved. Sitting on 0.9.12 I wrote alpha images renderer even
not realizing, that this 32-bit alpha support already is complete and
placed in official build. :shock: