SRL Archive - Discussions and Debates

Hey there,

How difficult would it be to create a multi-layered canvas on SMART? This would make it possible to clear & refresh a certain canvas without disturbing the other(s).

Here's an example of how I might use it:

Var
  SecondLayer: TCanvas;

procedure SMART_DrawDotsEx(Clear: boolean; pixels: TPointArray; color: TColor; var NewCanvas);
{$IFDEF SMART}
var
  i : integer;
begin
  if (not SMART_DebugSetup) then
    SMART_SetupDebug();

  CreateCanvas(NewCanvas);  //Create a fresh canvas
  NewCanvas.Pen.Color := color;
  if Clear then ClearRSCanvas(NewCanvas);  //Clear this canvas only

  for i:= 0 to high(pixels) do
  begin
    NewCanvas.moveto(pixels[i].x-1,pixels[i].y);
    NewCanvas.LineTo(pixels[i].x,pixels[i].y);
  end;

  //Maybe we need to free something here?  I dunno...

{$ELSE}
begin
{$ENDIF}

end;

Procedure DrawAndClear;
begin
  SMART_DrawDotsEx(False, DotArray, clRed, SecondLayer);  //Draw our dots on a new canvas defined as 'SecondLayer'
  if not (SecondLayer = NULL_CANVAS) then  //You get the idea
    ClearRSCanvas(SecondLayer);
end;

I hope this makes sense. Maybe Zyt3x or Mormonman, one of you two could throw some suggestions my way or even tell me if this is possible.

Thanks in advance.

I see how this could be very useful, but I'm not sure if it's possible though… I mean; It's possible, but I don't know how to do it :/