TRasterImage

type TRasterImage = class(TGraphic)

protected

  FSharedImage: TSharedRasterImage;

Shared image with existing handles, canvases, etc.

  function CanShareImage(); virtual;

CanShareImage - returns True if specified class of image can be shared.

  procedure Changed(); override;

Changed - method to call when properties have changed.

  function CreateDefaultBitmapHandle(); virtual;

Gets the default value for the Bitmap handle used in the class instance.

  procedure Draw(); override;

Renders the image to the specified canvas.

  function GetEmpty; override;

Gets the value for the Empty property.

  function GetHandle;

Gets the value for the Handle property.

  function GetBitmapHandle; virtual; abstract;

Gets the value for the BitmapHandle property.

  function GetMasked; virtual;

Gets the value for the Masked property.

  function GetMaskHandle; virtual; abstract;

Gets the value for the MaskHandle property.

  function GetMimeType; override;

Gets the value for the MimeType property.

  function GetPixelFormat; virtual; abstract;

GetPixelFormat - returns the pixel format for the Image.

  function GetRawImagePtr; virtual; abstract;

Gets a pointer with the raw image data.

  function GetRawImageDescriptionPtr; virtual; abstract;

Gets a pointer to the metadata for the raw image data.

  function GetTransparent; override;

Gets the value for the Transparent property.

  class function GetSharedImageClass; virtual;

Gets the class reference used to create new shared image instances in the class.

  function GetHeight; override;

Gets the value for the Height property.

  function GetWidth; override;

Gets the value for the Width property.

  procedure BitmapHandleNeeded; virtual;

Ensures that handles for the image and mask are valid for the raw image data.

  procedure HandleNeeded; virtual; abstract;

Ensures that a handle for the image is allocated in widgetset classes.

  procedure MaskHandleNeeded; virtual; abstract;

Ensures that a handle is allocated for the image mask (when needed).

  procedure PaletteNeeded; virtual; abstract;

Ensures that a handle for the palette is allocated.

  function InternalReleaseBitmapHandle; virtual; abstract;

InternalReleaseBitmapHandle - releases Bitmap Handle and returns its value.

  function InternalReleaseMaskHandle; virtual; abstract;

InternalReleaseMaskHandle - releases Mask Handle and returns its value.

  function InternalReleasePalette; virtual; abstract;

InternalReleasePalette - releases Palette Handle and returns its value.

  procedure SetBitmapHandle();

Sets the value for the BitmapHandle property.

  procedure SetMasked(); virtual;

Sets the value for the Masked property.

  procedure SetMaskHandle();

Sets the value for the MaskHandle property.

  procedure SetTransparent(); override;

Sets the value for the Transparent property.

  procedure UnshareImage(); virtual; abstract;

Unshares a shared image when its handle is changed or the save stream is freed.

  function UpdateHandles(); virtual; abstract;

Updates image handles when the raw image data is loaded.

  procedure SaveStreamNeeded;

Ensures that the save stream for the shared image is allocated.

  procedure FreeSaveStream;

Frees the save stream assigned to the internal shared image.

  procedure ReadData(); override;

Reads image data during component streaming.

  procedure ReadStream(); virtual; abstract;

ReadStream - loads image data into the raw image.

  procedure SetSize(); virtual; abstract;

SetSize - specifies height and width of Image.

  procedure SetHandle(); virtual;

Sets the Handle used for the image.

  procedure SetHeight(); override;

Sets the value for the Height property.

  procedure SetWidth(); override;

Sets the value for the Width property.

  procedure SetTransparentMode();

Sets the value for the TransparentMode property.

  procedure SetPixelFormat(); virtual; abstract;

Sets the value for the PixelFormat property.

  procedure WriteData(); override;

Writes raw image data to the specified stream.

  procedure WriteStream(); virtual; abstract;

Writes the image content to the specified stream instance.

  function RequestTransparentColor;

Gets the color used to represent transparent pixels in the image.

public

  constructor Create; override;

Constructor for the class instance.

  destructor Destroy; override;

Destroy is the destructor for TRasterImage: frees the canvas, and releases image then calls inherited Destroy.

  procedure Assign(); override;

Assign - copies details from Source according to data type.

  procedure Clear; override;

Removes raw image data and frees the internal save stream.

  procedure BeginUpdate();

BeginUpdate - start the update process.

  procedure EndUpdate();

EndUpdate - finishes the update process.

  procedure FreeImage; virtual;

Frees the image by resetting its handle.

  function BitmapHandleAllocated; virtual; abstract;

BitmapHandleAllocated - returns True if a handle has been allocated for the Bitmap.

  function MaskHandleAllocated; virtual; abstract;

MaskHandleAllocated - returns True if a handle has been allocated for the Mask.

  function PaletteAllocated; virtual; abstract;

PaletteAllocated - returns True if a Palette has been allocated.

  procedure LoadFromBitmapHandles();

Loads the image data from the specified Bitmap and Mask handles.

  procedure LoadFromDevice(); virtual;

Loads image data from the specified device context.

  procedure LoadFromStream();

LoadFromStream - loads data for the image from a specified data stream, optionally supplying its size.

  procedure LoadFromMimeStream(); override;

Loads image data from a stream for the specified MIME type.

  procedure LoadFromRawImage();

Loads image data from the specified TRawImage instance.

  procedure LoadFromIntfImage();

Loads the image from a TLazIntfImage instance.

  procedure SaveToStream(); override;

Saves image data to the specified stream.

  procedure GetSupportedSourceMimeTypes(); override;

Gets a list of supported MIME types for image data used in the image type.

  procedure GetSize();

Gets the image Width and Height from the metadata for the raw image.

  procedure Mask();

Applies the color used for transparent pixels to the image.

  procedure SetHandles(); virtual; abstract;

Sets handles for the bitmap and the mask to the specified values.

  function ReleaseBitmapHandle;

Releases the handle in the shared image without freeing the BitmapHandle.

  function ReleaseMaskHandle;

ReleaseMaskHandle - releases the Handle used for the Mask.

  function ReleasePalette;

ReleasePalette - release the Handle used for the Palette.

  function CreateIntfImage;

CreateIntfImage - creates an image on the Interface.

  property Canvas: TCanvas; [r]

The Canvas where the raster image is rendered.

  function HandleAllocated;

Indicates if a handle has been assigned for the shared image in the class.

  property BitmapHandle: HBITMAP; [rw]

BitmapHandle - the Handle that has been allocated for the Bitmap.

  property Masked: Boolean; [rw]

Masked - returns True if a Mask is being applied.

  property MaskHandle: HBITMAP; [rw]

The handle allocated for the Bitmap Mask.

  property PixelFormat: TPixelFormat; [rw]

Storage format for the Pixels in the Image.

  property RawImage: TRawImage; [r]

Provides access to the raw image data for the image type.

  property ScanLine []: Pointer; [r] platform ;

Provides indexed access to a scan line in the raw image data.

  property TransparentColor: TColor; [rw]

Color used for transparent pixels in the image.

  property TransparentMode: TTransparentMode; [rw]

Determines how transparent pixels are represented in the image.

end;

TRasterImage

TRasterImage - base class for a number of graphic controls, including TCustomBitmap and TCustomIcon, which use a raster of dots to display graphic information.

TGraphic

Abstract base class used for images in supported image formats.

TPersistent,IFPObserved

TObject