TRasterImage.Draw procedure

Declaration

procedure Draw(DestCanvas: TCanvas; const DestRect: TRect); override

Arguments

Description

Draw is an overridden method used to render the raster image to the specified canvas using the given rectangle. Draw implements the abstract method defined in the ancestor class.

DestCanvas contains the canvas instance where the raster image is rendered.

DestRect contains the canvas coordinates in DestCanvas where the image is drawn.

No actions are performed in the method if the Width or the Height for the image is 0 (zero).

Draw ensures that valid handles are available in BitMapHandle and MaskHandlle (when Masked is True). No actions are performed in the method when a valid BitmapHandle does not exist.

Draw uses the Device Contexts for Canvas and DestCanvas, and calls the StretchMaskBlt routine in the LCL interface to render the image using methods in the widgetset. The Changing method in DestCanvas is called before drawing the image. The Changed method in DestCanvas is called after the image is drawn.

See also

• Draw