ImageEn, unit iegdiplus

TIEPen


Declaration

TIEPen = class;


Description

TIEPen is a GDI+ Pen wrapper and VCL TPen wrapper. It is available via TIEBitmap.IECanvas.Pen.


Methods and Properties

Member Declaration Description
Color property Color: TColor; Color of drawing
LineJoin property LineJoin: TIECanvasPenLineJoin; If multiple lines are drawn how are they joined (e.g. as distinct lines or curved)
Transparency property Transparency: integer; Level of transparency of drawing (from 0 - fully transparent to 255 - fully opaque)
Style property Style: TPenStyle; Style of drawing
Width property Width: single; Width of drawing


Examples

// Draw an anti-aliased ellipse onto a TBitmap
iec := TIECanvas.Create(ABitmap.Canvas, true, true);
with iec do
begin
  Pen.Style := psSolid;
  Pen.Mode := pmCopy;
  Pen.Color := clRed;
  Brush.Style := bsClear
  Ellipse( Rect( 100, 100, 200, 200 ));
end;
iec.Free;

// Draw an anti-aliased ellipse onto a TIEBitmap
with iebmp.IECanvas do
begin
  Pen.Style := psSolid;
  Pen.Mode := pmCopy;
  Pen.Color := clRed;
  Brush.Style := bsClear
  Ellipse( Rect( 100, 100, 200, 200 ));
end;

// Draw an envelope with 50% transparency
with ImageEnView1.IEBitmap.IECanvas do
begin
  Pen.Mode := pmCopy;
  Pen.Style := psSolid;
  Pen.Color := clBlack;
  Pen.Transparency := 128;

  Brush.Color := clYellow;
  Brush.Style := bsSolid;
  Brush.Transparency := 128;

  // Draw outer rect
  Rectangle( 100, 100, 500, 300 );

  // Draw flap
  MoveTo( 100, 100 );
  LineTo( 300, 200 );
  LineTo( 500, 100 );
end;
ImageEnView1.Update();


// Draw a semi-transparent text box onto a bitmap
const
  Horz_Margin = 8;
  Vert_Margin = 3;
  Center_Text = False;
var
  x, y: integer;
  tw, rw, rh: integer;
  iec: TIECanvas;
  ss: string;
begin
  ss := 'This is my text';
  x := 100;
  y := 100;

  iec := TIECanvas.Create( Bitmap.Canvas, true, true);

  iec.Font.Assign( GetTextFont() );
  tw := iec.TextWidth(ss);
  rw := imax( tw + 2 * Horz_Margin, iec.TextWidth(minText) + 2 * Horz_Margin );
  rh := iec.TextHeight(ss) + 2 * Vert_Margin;

  if Center_Text then
    dec( x, rw div 2 );

  iec.Brush.Color := clYellow;
  iec.Brush.Style := bsSolid;
  iec.Brush.Transparency := 196;

  iec.Pen.Color := clBlack;
  iec.Pen.Style := psSolid;
  iec.Rectangle( x, y, x + rw, y + rh );

  iec.Brush.Style := bsClear;
  iec.TextOut(x + ( rw - tw ) div 2, y + Vert_Margin, ss);
  iec.Free;
end;


// Draw a rounded, semi-transparent scrollbar (anti-aliased)
const
  RX = 12; // round width
  RY = 12; // round height
  MINSLIDERW = 8; // minimum slider width
var
  scrollPos, scrollCount: integer;
  sliderWidth: double;
begin
  x := 100;
  y := 100;
  Width := 300;
  Height := 16;
  scrollCount := 20;
  scrollPos := 3;

  with ImageEnView1.IEBitmap.IECanvas do
  begin
    // paint brush and border
    Brush.Style := bsSolid;
    Brush.Color := clWhite;
    Brush.Transparency := 64;
    Pen.Color := clWhite;
    Pen.Style := psSolid;
    Pen.Mode := pmCopy;
    Pen.Width := 1;
    Pen.Transparency := 128;
    RoundRect( x, y, x + width, y + height, RX, RY );

    // paint slider
    Brush.Style := bsSolid;
    Brush.Color := clBlack;
    Brush.Transparency := 128;
    Pen.Width := 1;
    Pen.Transparency := 128;
    sliderWidth := width / scrollCount;
    if sliderWidth < MINSLIDERW then
      sliderWidth := MINSLIDERW;
    RoundRect( x + trunc(scrollPos * sliderWidth), y + 1, x + trunc(scrollPos * sliderWidth) + trunc(asliderWidth), y + height - 1, RX, RY);
    end;
end;