[Overview][Constants][Types][Classes][Procedures and functions][Variables][Index] Reference for unit 'Graphics' (#lcl)

TCanvas

[Properties (by Name)] [Methods (by Name)] [Events (by Name)]

TCanvas - where most of the drawing is performed

Declaration

Source position: graphics.pp line 877

type TCanvas = class(TFPCustomCanvas)

protected

  function DoCreateDefaultFont; override;

  

  function DoCreateDefaultPen; override;

  

  function DoCreateDefaultBrush; override;

  

  procedure SetColor(); override;

  

  function GetColor(); override;

  

  procedure SetHeight(); override;

  

  function GetHeight; override;

  

  procedure SetWidth(); override;

  

  function GetWidth; override;

  

  procedure SetPenPos(); override;

  

  procedure DoLockCanvas; override;

  

  procedure DoUnlockCanvas; override;

  

  procedure DoTextOut(); override;

  

  procedure DoGetTextSize(); override;

  

  function DoGetTextHeight(); override;

  

  function DoGetTextWidth(); override;

  

  procedure DoRectangle(); override;

  

  procedure DoRectangleFill(); override;

  

  procedure DoRectangleAndFill(); override;

  

  procedure DoEllipse(); override;

  

  procedure DoEllipseFill(); override;

  

  procedure DoEllipseAndFill(); override;

  

  procedure DoPolygon(); override;

  

  procedure DoPolygonFill(); override;

  

  procedure DoPolygonAndFill(); override;

  

  procedure DoPolyline(); override;

  

  procedure DoFloodFill(); override;

  

  procedure DoMoveTo(); override;

  

  procedure DoLineTo(); override;

  

  procedure DoLine(); override;

  

  procedure DoCopyRect(); override;

  

  procedure DoDraw(); override;

  

  procedure CheckHelper(); override;

  

  function GetClipRect; override;

  

  function GetPixel(); virtual;

  

  procedure CreateBrush; virtual;

  

  procedure CreateFont; virtual;

  

  procedure CreateHandle; virtual;

  

  procedure CreatePen; virtual;

  

  procedure CreateRegion; virtual;

  

  procedure DeselectHandles; virtual;

  

  procedure PenChanging(); virtual;

  

  procedure FontChanging(); virtual;

  

  procedure BrushChanging(); virtual;

  

  procedure RegionChanging(); virtual;

  

  procedure RealizeAutoRedraw; virtual;

  

  procedure RequiredState(); virtual;

  

  procedure SetHandle(); virtual;

  

  procedure SetInternalPenPos(); virtual;

  

  procedure SetPixel(); virtual;

  

  procedure FreeHandle; virtual;

  

public

  constructor Create;

  

Canvas constructor

  destructor Destroy; override;

  

Canvas destructor

  procedure Lock; virtual;

  

  procedure Unlock; virtual;

  

  procedure Refresh; virtual;

  

  procedure Changing; virtual;

  

  procedure Changed; virtual;

  

  procedure SaveHandleState; virtual;

  

  procedure RestoreHandleState; virtual;

  

  procedure Arc();

  

Use Arc to draw an elliptically curved line with the current Pen

  procedure Chord();

  

Chord draws a filled Chord-shape on the canvas

  procedure CopyRect(); virtual;

  

Copies the rectangle found at Source in SrcCanvas to the destination position Dest

  procedure Draw(); virtual;

  

Draw a graphic stored in SrcGraphic at the point X, Y

  procedure DrawFocusRect(); virtual;

  

  procedure StretchDraw(); virtual;

  

Draws the Graphic stored at SrcGraphic, stretched to fit the dimensions of the destination

  procedure Ellipse();

  

Ellipse draws a filled circle or ellipse on the canvas

  procedure FillRect();

  

  procedure FloodFill(); virtual;

  

  procedure Frame3d(); virtual;

  

  procedure Frame();

  

  procedure FrameRect();

  

  procedure GradientFill();

  

  procedure Line();

  

Draws a Line from X1, Y1 to X2, Y2

  procedure LineTo(); virtual;

  

LineTo draws a line from the current pen position to the new position: X1, Y1

  procedure MoveTo(); virtual;

  

Moves cursor to new position X1, Y1 without drawing anything

  procedure RadialPie(); virtual;

  

RadialPie uses Pie to draw a filled pie-shaped wedge on the canvas

  procedure Pie(); virtual;

  

Pie draws a filled Pie-shaped wedge on the canvas

  procedure PolyBezier();

  

Polybezier draws cubic Bezier curves

  procedure Polygon();

  

Polygon draws a closed, many-sided shape on the canvas, using the value of Pen

  procedure Polyline();

  

Polyline connects a set of points on the canvas

  procedure Rectangle();

  

  procedure RoundRect();

  

  procedure TextOut(); virtual;

  

Writes the Text string at the position X, Y on the canvas and leaves the pen at the end of the text

  procedure TextRect();

  

Writes Text string within a specified rectangle, according to predefined Style

  function TextExtent(); virtual;

  

  function TextHeight(); virtual;

  

  function TextWidth(); virtual;

  

  function HandleAllocated; virtual;

  

  function GetUpdatedHandle(); virtual;

  

  property Pixels: TColor; [rw]

  

  property Handle: HDC; [rw]

  

  property TextStyle: TTextStyle; [rw]

  

published

  property AutoRedraw: Boolean; [rw]

  

  property Brush: TBrush; [rw]

  

  property CopyMode: TCopymode; [rw]

  

  property Font: TFont; [rw]

  

  property Height: Integer; [r]

  

  property Pen: TPen; [rw]

  

  property Region: TRegion; [rw]

  

  property Width: Integer; [r]

  

  property OnChange: TNotifyEvent; [rw]

  

Event handler for a change in the canvas

  property OnChanging: TNotifyEvent; [rw]

  

Event handler while canvas is changing

end;

Inheritance

TCanvas

  

TCanvas - where most of the drawing is performed

|

TFPCustomCanvas

?

TObject

Description

TCanvas is a class that defines a very large number of drawing methods including methods for pen and colour selection, producing shapes and filling them, setting or clearing individual pixels, and producing graphic text.

The latest version of this document can be found at lazarus-ccr.sourceforge.net.