Seeing CLOUDS: But outside the sky is clear. How?

[Boleeman]

Ah ........ that's because the clouds are in digital form.


A Lazarus program to make clouds.

SHARPNESS  --->  Lower is fluffier. Higher is sharper.
DENSITY       --->  0.7=Nearly clear sky, 0.2=Nearly full of clouds.


Enjoy.

[Lulu]

Hi Boleeman, thank you for all your graphic demos!

I compiled the clouds demo in debug mode and an exception occurs on the line:

Code: Pascal  [Select][+][-]

1. procedure TForm1.Timer1Timer(Sender: TObject);
2. ...
3. col := RGBToColor(R + Round(z * (256 - R)), G + Round(z * (256 - G)), B + Round(z * (256 - B)));
4. ...

if I replace this line by this one, no more exception:

Code: Pascal  [Select][+][-]

1. col := RGBToColor(R + Round(z * (255 - R)), G + Round(z * (255 - G)), B + Round(z * (255 - B)));

Heaptrc report 102 unfreed memory block at the termination of the program.
If we add:

Code: Pascal  [Select][+][-]

1. procedure TForm1.FormDestroy(Sender: TObject);
2. var
3.   i: Integer;
4. begin
5.   SkyBmp.Free;
6.   for i := 0 to 3 do
7.   begin
8.     OctavesA[i].Free;
9.     OctavesB[i].Free;
10.   end;
11.   Clouds.Free;
12. end;
13.  

its not enough, there still remain 70 unfreed blocks.
Nothing serious, but it's better when the code ends cleanly.

[Boleeman]

Thanks Lulu. for finding those errors. For some reason they did not happen on my Dell AMD Cpu laptop.
I was in a hurry to upload yesterday, as I made quite a number of other programs.

For the clouds program I also forgot the destructor:

type
  TArray2D = class
  private
    FWidth, FHeight: Integer;
    FData: array of Double;
  public
    constructor Create(AWidth, AHeight: Integer);
    destructor Destroy; override;

and under implementation

{$R *.lfm} 

Add this:

destructor TArray2D.Destroy;
begin
  SetLength(FData, 0); // Or use Finalize(FData);
  inherited Destroy;
end;   




Thank you Lulu for letting me know.

TRon:  Yes it is confusing, but I like the clouds produced and thought it would be cool to share what I had to others.

[TRon]

Funny that when added (though right decision) it makes matters worse 

The 'problem' is that T2darray is a class and in the code it gets created, stored into a variable and that variable is used to for example smooth the data, which returns a new instance of T2darray and assigning to that same variable.

At quick glance there is not an easy fix. E.g. I dunno if it is possible to for instance apply the effect to the existing instance of the t2array that will achieve the same results.