FillRect don't work properly?
lazarus / 39-Graphics

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oraculus · 2015-02-07 10:46

Hello.
When I assign the height of a TImage and fill it with a color, all
work well. But when I make the height of the TImage more big, the
TImage only fill with the first values.
Here are the code example:
Code: [Select]  TvAsp: TImage;
  (...)
  Form1.TvAsp.Height:= 100;
  Form1.TvAsp.Canvas.Clear;
  Form1.TvAsp.Canvas.Brush.Color:=RGBToColor(255,255,255);
  Form1.TvAsp.Canvas.FillRect(Form1.TvAsp.BoundsRect);
  (...)
  Form1.TvAsp.Height:= 300;
  Form1.TvAsp.Canvas.Clear;
  Form1.TvAsp.Canvas.Brush.Color:=RGBToColor(255,255,255);
  Form1.TvAsp.Canvas.FillRect(Form1.TvAsp.BoundsRect);// Only fill a
Height of 100

It is a Lazarus's mistake?
Thank-you.

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taazz · 2015-02-07 12:19

Quote from: oraculus on February 07, 2015, 11:46:08 amHello.
When I assign the height of a TImage and fill it with a color, all
work well. But when I make the height of the TImage more big, the
TImage only fill with the first values.
Here are the code example:
Code: [Select]  TvAsp: TImage;
  (...)
  Form1.TvAsp.Height:= 100;
  Form1.TvAsp.Canvas.Clear;
  Form1.TvAsp.Canvas.Brush.Color:=RGBToColor(255,255,255);
  Form1.TvAsp.Canvas.FillRect(Form1.TvAsp.BoundsRect);
  (...)
  Form1.TvAsp.Height:= 300;
  Form1.TvAsp.Canvas.Clear;
  Form1.TvAsp.Canvas.Brush.Color:=RGBToColor(255,255,255);
  Form1.TvAsp.Canvas.FillRect(Form1.TvAsp.BoundsRect);// Only fill a
Height of 100

It is a Lazarus's mistake?
Thank-you.

Form1.TvAsp.BoundsRect has different values between those two calls?

EDIT:

Ok here is a small explanation of TImage.

TImage is a control that shows on screen the contents of what ever is
loaded in its picture property.
It has the ability to resize it to fit in the area enclosed by timage
it self. It has no content you can draw on and it is a simple gateway
to the underline graphic data that picture points to. If nothing is
loaded in the picture property then the timage has no contents and
nowhere to draw to. To overcome this problem the team decided to auto
create a bitmap the first time you try to draw something and you have
not loaded or created any picture to draw to, they used the TImage's
size as the bitmaps size after that first creation the bitmap persist
through out the life of timage it self until you change it your self.

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howardpc · 2015-02-07 12:52

You may find it more to your purpose to use ClientRect rather than
BoundsRect for scrollable controls such as forms.

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zeljko · 2015-02-07 13:59

He is using BoundsRect of TImage, not TForm one.

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howardpc · 2015-02-07 15:00

Ah, zeljko, you're right. My mistake.

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oraculus · 2015-02-07 18:08

Thank-you.
In my program, I put the TImage inside a ScrollBox.
I need that TImage's size changes into relation with the number of
canvas that the program uses in every case.
How can I do it?

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howardpc · 2015-02-07 19:30

Can you provide your current compilable code (with its resizing
shortcomings)? Then I expect someone can point you towards changes
that would make it behave how you want it to. Code snippets are
unsatisfactory, because others have to make too many assumptions about
the parts (could be 99% of your program) that are not known except to
you.

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oraculus · 2015-02-07 20:13

Yes. here it is:

http://astroser.net/syrius_fuente.zip

When you select the "Tecnicas" tab, put for example "36" in "Dias"
text box, and press "Transitos" button.
You can see planetary transits for 36 days.
Now put "365" in "Dias" text box, and press "Transitos" button.
You can't see planetary transits for 365 days. The list of planetary
transits must be much bigger, but the "TvAsp" TImage control don't
resize.
It will be interesting to publish the solution in this forum.

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howardpc · 2015-02-07 22:45

Try changing the beginning of your procedure to the following:

Code: [Select]procedure listaTecnicas(op: integer);
var
  f: TextFile;
  np, tx, tx2, nb1, nb2: string;
  nbp: array of string;
  contador, ini, fin, fig, tam, distancia: integer;
  sc: single;
  py: longint;
begin
  Form1.listaTec.Items.Clear;
  if op = 1 then
  begin
    AssignFile(F, ExtractFilePath(Application.ExeName) +
'transitos.txt');
  end
  else if op = 2 then
  begin
    AssignFile(F, ExtractFilePath(Application.ExeName) +
'sinastria.txt');
  end;
  Reset(f);
  // Aspectos en plan grafico
  contador := 0;
  while not EOF(f) do
  begin
    Application.ProcessMessages;
    ReadLn(f, tx);
    nbp := vbSplit(tx, ' ');
    if ((Length(nbp[0]) > 1)) then
    begin
      contador := contador + 1;
    end;
  end;
// changes start here:
  Form1.TvAsp.Picture.Bitmap.SetSize(Form1.Width, contador * 20);
  Form1.TvAsp.Picture.Bitmap.Canvas.Brush.Color:=RGBToColor(255,255,25
5); // Para que funcione
  Form1.TvAsp.Picture.Bitmap.Canvas.FillRect(Form1.TvAsp.BoundsRect);
  SetBkMode(Form1.TvAsp.Picture.Bitmap.Canvas.Handle, TRANSPARENT);
  Form1.TvAsp.Picture.Bitmap.Canvas.Brush.Color:=RGBToColor(255,255,25
5); // en Win y en Linux
  Form1.TvAsp.Picture.Bitmap.Canvas.Pen.Width:=1;
  Form1.TvAsp.Picture.Bitmap.Canvas.Font.Size:=8;

  contador := 0;
  Reset(f);
  while not EOF(f) do
  begin
    Application.ProcessMessages;
    ReadLn(f, tx);
    nbp := vbSplit(tx, ' ');
    if ((Length(nbp[0]) > 1)) then
    begin
      contador := contador + 1;
      py:=((contador -1) * 20) +1;
      if (op = 1) then begin // Transitos
        Form1.TvAsp.Picture.Bitmap.Canvas.Textout(1, py+3, nbp[0]);
        fig:=simbolo(nbp[1]);
        Dibuja_Planeta(False,Form1.TvAsp,Form1.sb,69,py,fig, 13);
        tam:=12;
        sc:=1;
        distancia:=vbVal(nbp[2]);
       
Form1.TvAsp.Picture.Bitmap.Canvas.Pen.Color:=RGBToColor(0,0,0);
        Form1.TvAsp.Picture.Bitmap.Canvas.Pen.Width:=1;
        simboloAspecto(Form1.TvAsp,85,py+5,tam,distancia, sc);
        fig:=simbolo(nbp[3]);
        Dibuja_Planeta(False,Form1.TvAsp,Form1.sb,97,py,fig, 13);
        Form1.TvAsp.Picture.Bitmap.Canvas.Textout(113, py+3, nbp[4]);
        if (nbp[7] <> '(.)') then begin
          ini:=vbInstr(nbp[7],'(');
          fin:=vbInstr(nbp[7],')');
          np:=Copy(nbp[7], ini+1, (fin-ini)-1); // Mid
          distancia:=vbVal(np);
         
Form1.TvAsp.Picture.Bitmap.Canvas.Pen.Color:=RGBToColor(0,0,0);
          Form1.TvAsp.Picture.Bitmap.Canvas.Pen.Width:=1;
          simboloAspecto(Form1.TvAsp,198,py+5,tam,distancia, sc);
        end;
      end
      else begin // Sinastria     
     ... etc.

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oraculus · 2015-02-08 10:17

Thank-you very much howardpc.
My only change has been:
Code: [Select]  Form1.TvAsp.Picture.Bitmap.SetSize(Form1.TvAsp.Width,
contador * 20);
  Form1.TvAsp.Height:= contador * 20; //  This must be still here
And now all work properly. 
You are more rapid than freepascal
Best regards from Spain.