FMX.Graphics.TCanvas.IntersectClipRect

• Up to Parent: TCanvas

Delphi

procedure IntersectClipRect(const ARect: TRectF); virtual;

C++

virtual void __fastcall IntersectClipRect(const System::Types::TRectF &ARect);

Properties

Type	Visibility	Source	Unit	Parent
procedure function	public	FMX.Graphics.pas FMX.Graphics.hpp	FMX.Graphics	TCanvas

Description

Defines the drawing area by intersecting the current clipping area of the TCanvas and a rectangle.

The ARect parameter specifies the rectangle used in the intersection.

If ARect is empty, IntersectClipRect does nothing. It does not raise any errors.

Note: The clipping rectangle only operates if the canvas state is first saved using SaveState.

Examples

Code structure example:

var
  MyCanvas: TCanvas;
  Save: TCanvasSaveState;
  MyRect : TRectF;
begin
  try  
    Save := MyCanvas.SaveState;
  
    // Create the clipping rectangle
    MyRect.Create (20, 20, 100, 100);   
    MyCanvas.IntersectClipRect (MyRect);
    
    // Do your drawing here

  finally   
    MyCanvas.RestoreState(Save);
  end;
end;

Complete demo example:

procedure TForm1.IntersectBtnClick(Sender: TObject);
var
  Canvas: TCanvas;
  MyRect: TRectF;
  Save: TCanvasSaveState;
begin
  Canvas := Image1.Bitmap.Canvas;
  MyRect := TRectF.Create(TPointF.Create(50, 50), 160, 160);
  Canvas.BeginScene;
  try
    Save := Canvas.SaveState;
  try
    Canvas.InterSectClipRect(MyRect);
    Canvas.Stroke.Color := TAlphaColorRec.Lime;
    Canvas.Stroke.Thickness := 3;
    Canvas.Stroke.Dash := TStrokeDash.Dash;
    Canvas.DrawRect(MyRect, 0, 0, [], 1);
    Canvas.Fill.Color := TAlphaColorRec.Red;
    Canvas.Fill.Kind := TBrushKind.Solid;
    Canvas.FillEllipse(TRectF.Create(TPointF.Create(100, 125), 275, 150), 100);
  
  finally
    Canvas.RestoreState(Save);
  end;
  finally
    Canvas.EndScene;
  end;
end;

See Also

• FMX.Graphics.TCanvas.ExcludeClipRect
• System.Types.TRectF