[Solved] How can I use TBGRALayeredBitmap with multiple images in real
time?
lazarus / 39-Graphics

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loaded · 2020-03-06 06:54

Hi All
I have 3 different image objects with a resolution of 1920x1080, I can
layer them and at the same time, I can display each image with a
transparency value specific to the following code.

Code: Pascal  [Select][+][-]window.onload = function(){var x1 =
document.getElementById("main_content_section"); if (x1) { var x =
document.getElementsByClassName("geshi");for (var i = 0; i unit
Unit1; {$mode objfpc}{$H+} interface uses  bgrabitmap,
BGRABitmapTypes,BGRALayers,  Classes, SysUtils, Forms, Controls,
Graphics,  Dialogs, StdCtrls, ExtCtrls, Menus, Buttons,
ComCtrls; type   { TForm1 }   TForm1 = class(TForm)    BitBtn1:
TBitBtn;    Image1: TImage;    Image2: TImage;    Image3: TImage;   
Render: TImage;    TrackBar1: TTrackBar;    TrackBar2: TTrackBar;   
TrackBar3: TTrackBar;    procedure BitBtn1Click(Sender: TObject);   
procedure TrackBar1Change(Sender: TObject);    function
blayers:Boolean;   private   public   end; var  Form1:
TForm1;implementation {$R *.lfm}  { TForm1 }  function
btobgra(bt:TBitmap):Tbgrabitmap;var  br:Tbgrabitmap;begin 
result:=Tbgrabitmap.Create(bt,false);end; function
 TForm1.blayers:Boolean;var layer:TBGRALayeredBitmap;begin    try   
render.Picture:=nil;    render.canvas.Brush.Color:=clWhite;   
render.canvas.FillRect(render.Canvas.ClipRect);   
layer:=TBGRALayeredBitmap.Create(render.Width,render.Height);   
layer.AddLayer(btobgra(Image1.Picture.Bitmap),TrackBar1.Position);   
layer.AddLayer(btobgra(Image2.Picture.Bitmap),TrackBar2.Position);   
layer.AddLayer(btobgra(Image3.Picture.Bitmap),TrackBar3.Position);   
layer.Draw(Render.canvas,0,0);    layer.Free;    result:=true;   
except    result:=false;    end;end;  procedure
TForm1.BitBtn1Click(Sender: TObject); var   cron:cardinal;begin 
cron:=GetTickCount64;  if blayers then  TButton(sender).Caption:=float
tostr((GetTickCount64-cron)/1000);end; procedure
TForm1.TrackBar1Change(Sender: TObject); var   cron:cardinal;begin 
cron:=GetTickCount64;  if blayers then
 Form1.Caption:=floattostr((GetTickCount64-cron)/1000);end;  end.   
I am making possible changes within the trackbar onchange procedure.
In the meantime, there is a delay in imaging.
What's more, the white screen issue arises in continuous use.
Then I have to close the program.

I would gladly listen if there are any suggestions and suggestions to
be able to do the above process without any problem simultaneously
with the change of trackbar position.
Respects.

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circular · 2020-03-06 09:46

Hello

I suppose your code creates the layered image every time it is
displayed.

You can instead create it once and then set the opacity on the fly
with LayerOpacity property.

Also use AddOwnedLayer instead of AddLayer to avoid memory leak.

Regards

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loaded · 2020-03-06 11:31

Mr. Circular , You’re a great help, i must say.
You made my job very easy.

I would like to ask one more thing that there may be another more
useful thing to learn;
Is there any alternative method instead of the draw method?
Regards.

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circular · 2020-03-06 11:37

You're welcome.

Instead of Draw you can call ComputeFlatImage to get the resulting
image.

What else would you like to do?

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loaded · 2020-03-06 12:18

It was good that I learned the ComputeFlatImage method.

Quote from: circular on March 06, 2020, 12:37:27 pmWhat else would you
like to do?

What more, thanks to you, I solved my problem.

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circular · 2020-03-06 19:36

Ok