Unit contains definitions for many fundamental classes and types used in graphic applications A record holding Data about the current Font The Operating System Handle for the current Font The Height (in pixels) if the current Font The Pitch (in points) of the currentFont The Style of the Font Bold, Italic, Strikeout or Underlined The Character Set of the current Font (expresed as an integer) The Name (as a string) of the current Font Default Data for any new Font

New TFont instances are initialized with the values in this structure.

About font default values: The default font is chosen by the interfaces depending on the context.

For example, there can be a different default font for a button and a groupbox.

 How the Text is to be laid out in the Text Rectangle At the Bottom, Centre or Top of the available window or box The Style of the Text to be drawn in a rectangle

The Style of the Text to be drawn in a rectangle

  • Alignment : TextRect Only: horizontal alignment
  • Layout : TextRect Only: vertical alignment
  • SingleLine: boolean; If WordBreak is false then process #13, #10 as standard chars and perform no Line breaking.
  • Clipping : boolean; TextRect Only: Clip Text to passed Rectangle
  • ExpandTabs: boolean; currently ignored
  • ShowPrefix: boolean; TextRect Only: Process first single ampersand per line as an underscore and draw double ampersand as a single ampersand
  • Wordbreak : boolean; TextRect Only: If line of text is too long to fit between left and right boundaries, try to break into multiple lines between words
  • Opaque : boolean; TextRect: Fills background with current Brush
  • Opaque : TextOut : Fills background with current foreground color
  • SystemFont: Boolean; Use the system font instead of Canvas Font
  • RightToLeft: Boolean; For RightToLeft text reading (Text Direction)
 Style of Brush to be used TProgressEvent - for monitoring the progress of a drawing process TPortableNetworkGraphic - a PNG image Primitive ancestor class, mainly for Delphi compatibility TGraphicsObject - In Delphi VCL this is the ancestor of TFont, TPen and TBrush.
Since FPC 2.0 the LCL uses TFPCanvasHelper as ancestor. The Font to be used for drawing Text

Most of the data about the font are dealt with by the protected procedures GetData and SetData which operate on TFontData

Individual properties such as Character Set, colour and size can be accessed in the public area

 Font constructor Opens a new instance of the class and sets defaults for character set, colour, size etc Font destructor Assign - copies the LogFont or Source settings to itself

Method: TFont.Assign

Params: ALogFont: TLogFont or

Source: another font

Returns: nothing

Copies the logfont or source settings to itself The Character Set to be used by the currentFont Colour of the current Font Default is the same as the text used for the rest of the Window The Height of the current Font Name of the Font Pitch type of the Font Fixed or variable pitch, or Default
Reads or writes a flag to determine pitch type Font Size in pixels Style of the Font Bold, Italic, Strike out, Underline
Property is a set, so may contain zero or more of the above (if set is empty, Normal font is displayed) The Data associated with the current Pen The Operating System Handle associated with the current Pen The Colour of the curent Pen The Width in pixels of the current Pen The Style asociated with the current Pen The Style asociated with the current Pen
Can take any of the values: psSolid, psDash, psDot, psDashDot, psDashDotDot, psinsideFrame, psPattern,psClear The current Pen for drawing on the current Canvas Pen Constructor Most of its properties are inherited from the parent class Pen Destructor Most of its properties are inherited from the parent class Copies the Source Pen to itself the Operating System Handle for the current Pen Reads or writes a flag to determine the handle The Colour of the current Pen Reads or Writes a flag to determine the colour. Default is black The Mode for the current Pen Can take any of the values:
pmBlack, pmWhite, pmNop, pmNot, pmCopy, pmNotCopy,
pmMergePenNot, pmMaskPenNot, pmMergeNotPen, pmMaskNotPen, pmMerge,
pmNotMerge, pmMask, pmNotMask, pmXor, pmNotXor
Default is pmCopy The Style of the current Pen Can be one of the following:
psSolid, psDash, psDot, psDashDot, psDashDotDot, psinsideFrame, psPattern,psClear
Default is psSolid The Width in pixels of the current Pen The Data associated with the current Brush The Operating System Handle associated with the current Brush The Colour to be used by the current Brush The Bitmap on which the current Brush is working The Style to be used by the current Brush Enumerated type defined in TBrushStyle The Brush to be used to Paint on the current Canvas A Brush is typically used to fill an enclosed area on theCanvas with one particular colour or coloured pattern Assign - copies a Source Brush to itself Method: TBrush.Assign
Params: Source: Another brush
Returns: nothing
Copies the source brush to itself Source - another Brush Brush constructor Inherits most of its properties from ancestor Classes Brush destructor Inherits properties to remove Brush and frees Handle The BitMap associated with the current Brush Reads or writes a flag to determine the current BitMap Operating System Handle for this Brush Reads or writes flag to determine system Handle The Colour of the current Brush Reads or writes a flag to determine the Colour. Default is White Style of the Brush Enumerated type - default Solid The Data about the current Region on the Screen or Canvas At present the Region can only be rectangular; the ability to define it as a Polygon is not yet implemented A defined Region on the screen, in which text is written TRegionData (in same Unit) TRegion constructor TRegion destructor Assign - copies Source to itself Operating System Handle for this Region HRGN THandle The rectangle to be used for clipping text Base class for dealing with Graphic images The TGraphic class is an abstract base class for dealing with graphic images such as bitmaps, pixmaps, icons, and other image formats. It does not contain an actual area for displaying the image; this is provided by the descendant classes eg BitMap, Icon etc which have a Canvas element defined
LoadFromFile - Read the graphic from the file system. The old contents of the graphic are lost. If the file is not of the right format, an exception will be generated.
SaveToFile - Writes the graphic to disk in the file provided.
LoadFromStream - Like LoadFromFile except source is a stream (e.g. TBlobStream ).
SaveToStream - stream analogue of SaveToFile .
LoadFromClipboardFormat - Replaces the current image with the data provided. If the TGraphic does not support that format it will generate an exception.
SaveToClipboardFormats - Converts the image to a clipboard format. If the image does not support being translated into a clipboard format it will generate an exception.
Height - The native, unstretched, height of the graphic.
Palette - Color palette of image. Zero if graphic doesn't need/use palettes.
Transparent - Some parts of the image are not opaque, ie the background can be seen through.
Width - The native, unstretched, width of the graphic.
OnChange - Called whenever the graphic changes
PaletteModified - Indicates in OnChange whether color palette has changed. Stays true until whoever is responsible for realizing this new palette (ex: TImage) sets it to False.
OnProgress - Generic progress indicator event. Propagates out to TPicture and TImage OnProgress events.

As many of the methods and properties are virtual and/or abstract, it is the responsibility of the application programmer to supply suitable methods when implementing any descendant classes Monitor the progress of the drawing TGraphic constructor Virtual method, so recommend that a constructor be supplied to override this method in descendant classes LoadFromFile - Read the graphic from the file system. LoadFromFile - Read the graphic from the file system.
The old contents of the graphic are lost.
If the file is not of the right format, an exception will be generated. Incorrect file format generates an exception The name of the file containing the graphic, held as a string SaveToFile - Writes the graphic to disk in the file provided. SaveToFile - Writes the graphic to disk in the file whose name is provided. The name of the file to which the graphic will be written LoadFromStream - reads graphic data from a stream (e.g. TBlobStream ) LoadFromStream - Like LoadFromFile except source is a stream (e.g. TBlobStream) Identity of the stream from which the graphic data are to be read SaveToStream - write graphic data to a stream SaveToStream - write graphic data to a stream Identity of the stream to which the graphic data are to be written LoadFromMimeStream - reads graphic data from a MIME stream Load the graphic data from a Lazarus Resource (eg a *.lrs file) LoadFromClipboardFormat - Replace the current image with the contents of the clipboard LoadFromClipboardFormat - Replaces the current image with the data provided from the clipboard. If the TGraphic does not support that format it will generate an exception. Load the data from the clipboard using the format type specified by ClipboardType and the format identifier FormatID SaveToClipboardFormats - Converts the image to a clipboard format SaveToClipboardFormats - Converts the image to a clipboard format If the image does not support being translated into a clipboard format it will generate an exception Identity of the clipboard format Saves the data to a clipboard of Type ClipboardType using the format FormatID Gets a list of the MIME types that are supported Finds the default MIME type Is this an empty (blank) graphic? Height - The native, unstretched, height of the graphic. Has the graphic been modified? Event handler for any change in the data Event handler for monitoring progress of the graphic Palette - Color palette of image Palette - Color palette of image. Zero if graphic doesn't need/use palettes Has the palette of colours been modified? Transparent - Some parts of the image are not opaque. ie the background can be seen through Width - The native, unstretched, width of the graphic. TPicture is a TGraphic container, used in place of a TGraphic if the graphic can be of any TGraphic class.

TPicture is a TGraphic container. It is used in place of a TGraphic if the graphic can be of any TGraphic class.

It is not a direct descendant of TGraphic, so you will not see TGraphic listed in the Inheritance chart, but it contains a property Graphic, of type TGraphic, so can contain all the properties of a TGraphic

Defines many private methods for getting and storing various sorts of images such as bitmaps, pixmaps, icons, PNGs etc

It does not itself contain a defined area for displaying the image, but this is supplied by the descendant classes such as BitMap, PixMap, PNG or Icon, which define a Canvas property.

LoadFromFile and SaveToFile are polymorphic. For example, if the TPicture is holding an Icon, you can LoadFromFile a bitmap file, whereas if the class is TIcon you could only read .ICO files.

  • LoadFromFile - Reads a picture from disk. The TGraphic class created is determined by the file extension of the file. If the file extension is not recognized an exception is generated.
  • SaveToFile - Writes the picture to disk.
  • LoadFromClipboardFormat - ToDo: Reads the picture from the handle provided in the given clipboard format. If the format is not supported, an exception is generated.
  • SaveToClipboardFormats - ToDo: Allocates a global handle and writes the picture in its native clipboard format (CF_BITMAP for bitmaps, CF_METAFILE for metafiles, etc.). Formats will contain the formats written. Returns the number of clipboard items written to the array pointed to by Formats and Datas or would be written if either Formats or Datas are nil.
  • SupportsClipboardFormat - Returns true if the given clipboard format is supported by LoadFromClipboardFormat
  • Assign - Copies the contents of the given TPicture. Used most often in the implementation of TPicture properties.
  • RegisterFileFormat - Register a new TGraphic class for use in LoadFromFile.
  • RegisterClipboardFormat - Registers a new TGraphic class for use in LoadFromClipboardFormat.
  • UnRegisterGraphicClass - Removes all references to the specified TGraphic class and all its descendants from the file format and clipboard format internal lists.
  • Height - The native, unstretched, height of the picture.
  • Width - The native, unstretched, width of the picture.
  • Graphic - The TGraphic object contained by the TPicture
  • Bitmap - Returns a bitmap. If the contents is not already a bitmap, the contents are thrown away and a blank bitmap is returned.
  • Pixmap - Returns a pixmap. If the contents is not already a pixmap, the contents are thrown away and a blank pixmap is returned.
  • PNG - Returns a png. If the contents is not already a png, the contents are thrown away and a blank png ( TPortableNetworkGraphic) is returned.
  • PNM - Returns a pnm. If the contents is not already a pnm, the contents are thrown away and a blank pnm ( TPortableAnyMapGraphic) is returned.
  • Jpeg - Returns a jpeg. If the contents is not already a jpeg, the contents are thrown away and a blank jpeg ( TJPegImage) is returned.
 Monitor progress of drawing process TPicture constructor TPicture destructor Any destructor method defined here will override destructors defined in ancestor classes LoadFromFile - Reads a picture from disk LoadFromFile - Reads a picture from disk. The TGraphic class created is determined by the file extension of the file. If the file extension is not recognized an exception is generated The name of the file containing the picture, stored as a string SaveToFile - Writes the picture to disk The name of the file to save the picture, stored as a string LoadFromClipboardFormat - Reads the picture from the handle provided in the given clipboard format LoadFromClipboardFormat - ToDo: Reads the picture from the handle provided in the given clipboard format. If the format is not supported, an exception is generated The identifier for the clipboard format Reads the picture from a clipboard of type ClipboardType using the format FormatID SaveToClipboardFormats - Allocates a global handle and writes the picture in its native clipboard format SaveToClipboardFormats - ToDo: Allocates a global handle and writes the picture in its native clipboard format (CF_BITMAP for bitmaps, CF_METAFILE for metafiles, etc.). Formats will contain the formats written. Returns the number of clipboard items written to the array pointed to by Formats and Datas or would be written if either Formats or Datas are nil. Identity of the clipboard format SupportsClipboardFormat - Returns true if the given clipboard format is supported by LoadFromClipboardFormat Boolean - returns true if format supported Identity of the clipboard format Assign - Copies the contents of the given TPicture Assign - Copies the contents of the given TPicture. Used most often in the implementation of TPicture properties. RegisterFileFormat - Register a new TGraphic class for use in LoadFromFile RegisterClipboardFormat - Registers a new TGraphic class for use in LoadFromClipboardFormat UnRegisterGraphicClass - Removes all references to the specified TGraphic UnRegisterGraphicClass - Removes all references to the specified TGraphic class and all its descendants from the file format and clipboard format internal lists Clear - removes the graphic Bitmap - Returns a bitmap Bitmap - Returns a bitmap. If the contents is not already a bitmap, the contents are thrown away and a blank bitmap is returned Pixmap - Returns a pixmap Pixmap - Returns a pixmap. If the contents is not already a pixmap, the contents are thrown away and a blank pixmap is returned PNG - Returns a png PNG - Returns a png. If the contents is not already a png, the contents are thrown away and a blank png ( TPortableNetworkGraphic) is returned Icon contained within the picture Graphic - The TGraphic object contained by the TPicture Height - The native, unstretched, height of the picture Width - The native, unstretched, width of the picture Event handler for any change in the picture Event handler for monitoring progress in drawing the picture EInvalidGraphic - exception handler for an invalid graphic EInvalidGraphicOperation - exception handler for invalid graphic operation TCanvas - where most of the drawing is performed 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. Canvas constructor Canvas constructor: creates a new instance of the class TCanvas Canvas destructor Canvas destructor: removes this instance of TCanvas and makes its resources available Use Arc to draw an elliptically curved line with the current Pen Method: TCanvas.Arc
Params: ALeft, ATop, ARight, ABottom, sx, sy, ex, ey
Returns: Nothing

Use Arc to draw an elliptically curved line with the current Pen. The values sx,sy, and ex,ey represent the starting and ending radial-points between which the Arc is drawn. Use Arc to draw an elliptically curved line with the current Pen Method: TCanvas.Arc
Params: ALeft, ATop, ARight, ABottom, angle1, angle2
Returns: Nothing

Use Arc to draw an elliptically curved line with the current Pen.
The angles angle1 and angle2 are 1/16th of a degree.
For example, a full circle equals 5760 (16*360).
Positive values of Angle and AngleLength mean counter-clockwise while negative values mean clockwise direction.
Zero degrees is at the 3 o'clock position.

Params: x1, y1, x2, y2, StartAngle16Deg, EndAngle16Deg

Use Chord to draw a filled Chord-shape on the canvas.

The angles angle1 and angle2 are 1/16th of a degree. For example, a full circle equals 5760(16*360).

Positive values of Angle and AngleLength mean counter-clockwise while negative values mean clockwise direction. Zero degrees is at the 3 o'clock position.

Alternatively the starting and ending points may be specified as radial points (sx, sy, ex, ey)

 Draw a filled-chord shape starting and finishing at the specified angular positions on the circumference Chord draws a filled Chord-shape on the canvas Method: TCanvas.Chord
Params: x1, y1, x2, y2, StartAngle16Deg, EndAngle16Deg
Returns: Nothing

Use Chord to draw a filled Chord-shape on the canvas. The angles angle1 and angle2 are 1/16th of a degree. For example, a full circle equals 5760(16*360).
Positive values of Angle and AngleLength mean counter-clockwise while negative values mean clockwise direction.
Zero degrees is at the 3 o'clock position. Copies the rectangle found at Source in SrcCanvas to the destination position Dest Draw a graphic stored in SrcGraphic at the point X, Y Draws the Graphic stored at SrcGraphic, stretched to fit the dimensions of the destination

DestRec

 Ellipse draws a filled circle or ellipse on the canvas Method: TCanvas.Ellipse
Params: X1, Y1, X2, Y2
Returns: Nothing

Use Ellipse to draw a filled circle or ellipse on the canvas. Draws a Line from X1, Y1 to X2, Y2 LineTo draws a line from the current pen position to the new position: X1, Y1 Moves cursor to new position X1, Y1 without drawing anything RadialPie - draw a filled pie-shaped wedge on the canvas with specified start and end coordinates, and starting and ending angular positions

Params: x1, y1, x2, y2, StartAngle16Deg, EndAngle16Deg: Integer

Use Pie to draw a filled pie-shaped wedge on the canvas.

The angles StartAngle16Deg and EndAngle16Deg are 1/16th of a degree. For example, a full circle equals 5760 (16*360).

Positive values of Angle and AngleLength mean counter-clockwise while negative values mean clockwise direction. Zero degrees is at the 3 o'clock position.

 RadialPie uses Pie to draw a filled pie-shaped wedge on the canvas Method: TCanvas.RadialPie
Params: x1, y1, x2, y2, StartAngle16Deg, EndAngle16Deg: Integer
Returns: Nothing

Uses Pie to draw a filled pie-shaped wedge on the canvas.
The angles StartAngle16Deg and EndAngle16Deg are 1/16th of a degree.
For example, a full circle equals 5760 (16*360).
Positive values of Angle and AngleLength mean counter-clockwise while negative values mean clockwise direction.
Zero degrees is at the 3 o'clock position Pie draws a filled Pie-shaped wedge on the canvas Method: TCanvas.Pie
Params: EllipseX1, EllipseY1, EllipseX2, EllipseY2, StartX, StartY, EndX, EndY
Returns: Nothing

Use Pie to draw a filled Pie-shaped wedge on the canvas. The pie is part of an ellipse between the points EllipseX1, EllipseY1, EllipseX2, EllipseY2. The values StartX, StartY and EndX, EndY represent the starting and ending radial-points between which the Bounding-Arc is drawn.
Polybezier draws cubic Bezier curves Method: TCanvas.PolyBezier
Params: Points, Filled, Continous
Returns: Boolean

Use Polybezier to draw cubic Bezier curves.
The first curve is drawn from the first point to the fourth point with the second and third points being the control points.
If the Continuous flag is TRUE then each subsequent curve requires three more points, using the end-point of the previous Curve as its starting point, the first and second points being used as its control points, and the third point its end-point.

If the continous flag is set to FALSE, then each subsequent Curve requires 4 additional points, which are used exactly as in the first curve.

Any additonal points which do not add up to a full bezier(4 for Continuous, 3 otherwise) are ingored. There must be at least 4 points for an drawing to occur.

If the Filled Flag is set to TRUE then the resulting Poly-Bezier will be drawn as a Polygon. Polygon draws a closed, many-sided shape on the canvas, using the value of Pen Method: TCanvas.Polygon
Params: Points: array of TPoint; Winding: Boolean = False; StartIndex: Integer = 0; NumPts: Integer = -1
Returns: Nothing

Use Polygon to draw a closed, many-sided shape on the canvas, using the value of Pen . After drawing the complete shape, Polygon fills the shape using the value of Brush .

The Points parameter is an array of points that give the vertices of the polygon.
Winding determines how the polygon is filled. When Winding is True, Polygon fills the shape using the Winding fill algorithm.
When Winding is False, Polygon uses the even-odd (alternative) fill algorithm.
StartIndex gives the index of the first point in the array to use. All points before this are ignored.
NumPts indicates the number of points to use, starting at StartIndex .
If NumPts is -1 (the default), Polygon uses all points from StartIndex to the end of the array.
The first point is always connected to the last point.
To draw a polygon on the canvas, without filling it, use the Polyline method, specifying the first point a second time at the end. Polyline connects a set of points on the canvas Method: TCanvas.Polyline
Params: Points: array of TPoint; StartIndex: Integer = 0; NumPts: Integer = -1
Returns: Nothing

Use Polyline to connect a set of points on the Canvas . If you specify only two points, Polyline draws a single line.
The Points parameter is an array of points to be connected.
StartIndex identifies the first point in the array to use.
NumPts indicates the number of points to use. If NumPts is -1 (the default), PolyLine uses all the points from StartIndex to the end of the array.
Calling the MoveTo function with the value of the first point, and then repeatedly calling LineTo with all subsequent points will draw the same image on the canvas. However, unlike LineTo , Polyline does not change the value of PenPos . Writes the Text string at the position X, Y on the canvas and leaves the pen at the end of the text Writes Text string within a specified rectangle, according to predefined Style Writes Text string within a specified rectangle, according to predefined Style
The boundaries of the rectangle are specified in ARect
X, Y specify the starting point for writing the Text within the rectangle
TextStyle determines whether the text is justified, centered, word-wrapped etc. If the Style argument is omitted, defaults are assumed Event handler for a change in the canvas Event handler while canvas is changing TSharedImage - base class for reference counted images Increase reference count Decrease reference count Release the handle for this image and free its resources The number of references to this shared image Has a handle been allocated for this image? The place where the actual image of a bitmap is stored

Descendant of TSharedImage for TBitmap.

If a TBitmap is assigned to another TBitmap, only the reference count will be increased and both will share the same TBitmapImage Release the handle for the bitmap mask Release the bitmap handle Is the bitmap image empty? Find the format for the pixels (ie the number of bits per pixel) BitmapImage destructor Determine the type of the bitmap handle The stream to which the data are to be saved The type of the stream for saving the data TBitmap is the data of an image, and can be loaded from a file, stream or resource in .bmp or .xpm format

TBitmap is the data of an image. The image can be loaded from a file, stream or resource in .bmp (windows bitmap format) or .xpm (XPixMap format)

The loading routine automatically recognizes the format, so it is also used to load the images from Delphi form streams (e.g. .dfm files) or FreePascal/Lazarus form streams (.lfm)

When the handle is created, it is up to the interface (gtk, win32, ...) to convert it automatically to the best internal format. That is why the Handle is interface dependent.

To access the raw data, see TLazIntfImage

BitMap constructor BitMap constructor. The supplied code can override the definition from ancestor classes BitMap destructor BitMap destructor. The supplied code can override the method defined for ancestor classes Assign: find out about the Source of the call. Assign: find out about the Source of the call. If the BitMap data are already in use, the data are shared; if not, a new BitMap is produced Release (remove) the image, freeing the resources used Is a handle allocated for this bitmap? Returns TRUE if a handle has been allocated Is a handle allocated for the bitmap mask? Returns TRUE if a mask handle has been allocated Has a colour palette been allocated for this bitmap? Returns TRUE if a colour palette has been allocated Create an image in the specified rectangle, using the given bitmap and mask handles LoadFromDevice: obtain BitMap data from a device with Handle DC Checks that the Resource Type specified in the string argument is a valid Lazarus type Returns TRUE if a valid resource type is found The target resource type specified as a string LoadFromStream: obtains BitMap data from a Stream LoadFromLazarusResource: obtain data from a valid Lazarus Resource Stream LoadFromLazarusResource: obtain data from a valid Lazarus Resource Stream
Checks for the presence of a valid Lazarus Resource, then uses LoadFromStream to acquire the data ToDo ToDo LoadFromMimeStream - get Bitmap data from the specified MIME stream Gets a list of the supported MIME types for the source file Finds the default MIME type Finds the available file extensions LoadFromXPMFile: obtain data from file in native PixMap format Masks the bitmap using a transparent colour Saves bitmap data to a stream Reads data from a stream Writes data to a stream Release the bitmap handle, effectively freeing resources Release the current palette Get the appropriate FPReader for the given file extension Get the default FPReader Get the default FPWriter Read Bitmap data from stream using the FPImage reader Write bitmap data to a native stream Create an interface image The canvas on which this bitmap is drawn

The Canvas is where all the drawing and painting is performed.

The properties are described in TCanvas

The operating system Handle ssociated with this bitmap The type of system handle The system handle associated with the bitmap mask Whether using monochrome display PixelFormat - number of bits per pixel The transparent colour used for masks etc The mode used for transparency PixMap - a class derived from TBitMap , with wrapper to deal specifically with PixMaps (ie using 'XPM' format) PixMap - Checks that specified resources (PixMap image, File for storage, Stream for writing) are of correct type and format, organises saving and writing LazarusResourceTypeValid - checks that specified resource has correct format Returns True if resource type is 'XPM' WriteStream - writes PixMap data to specified stream True if size of data in stream has been specified GetDefaultFPReader - obtains the correct tool Returns the correct tool for reading GetDefaultFPWriter - obtains the correct tool Returns the correct tool for writing A class of Bitmap using the FPImage reader and writer (ie customised for FreePascal) Find the file extensions for valid bitmap image files Is the given file extension supported? Get the FPReader tool appropriate to the given file extension Get the FPWriter tool appropriate for the given file extension Get the default FPReader, if no extension-specific tool Get the default FPWriter, if no extension-specific tool Read the data from a Stream Write the data to a stream Get the default MIME type for this bitmap TPortableNetworkGraphic - a PNG image TIcon - icons, small images typically associated with applications, controls, etc. Stored in files with .ico extension

TIcon reads and writes .ICO file format.

A .ico file typically contains several versions of the same image.

When loading, the largest/most colourful image is loaded as the TBitmap and so can be handled as any other bitmap. Any other versions of the images are available via the Bitmaps property

Writing is not (yet) implemented.

 Bitmaps - the list of alternative bitmaps (of various sizes) TIcon destructor TIcon destructor. Method can override the destructor defined in ancestor classes Add a bitmap to the current list Note that Ownership passes to TIcon ColorToIdent - given a Color value, find its name (Ident) in the look-up table of Colors Returns True if there is a valid entry in the Colors look-up table the Color value to be sought in the look-up table Ident - the name of the supplied Color as found in the look-up table of Colors IdentToColor - given a colour identifier (name) returns the colour value Returns True if Ident is part of a valid entry in the look-up table of Colors Ident - the suppied name for the required Color The Color returned from the look-up table, with the name supplied in Ident SysColorToSysColorIndex - if Color is one of the system colours, returns the Index of the system colour If Color is not a system color, returns -1 Returns the Index value of the Color if it is a system colour, otherwise returns -1 The Color for processing ColorToRGB - given a Color value, converts into RGB Returns the original Color transformed to RGB The original Color for processing ColorToString - given a colour value, returns a corresponding colour name like 'Green' Returns the name of the colour, expressed as a string (like 'Green') The Color value for processing StringToColor - given a colour name like 'Blue', returns the corresponding colour value Returns the colour corresponding to the name in String S S - the name of the required colour, expressed as a string Finds the Blue component of the supplied colour Returns the Blue component of the colour specified in RGB The colour for processing, expressed as a RGB value Finds the Green component of the supplied colour Returns the Green component of the colour specified in RGB The colour for processing, expressed as RGB Finds the Red component of the supplied colour Returns the Red component of the colour specified in RGB The colour for processing, expressed as RGB RedGreenBlue - decomposes a composite colour into its component Red, Green and Blue values The colour for processing, expressed as RGB The Red component of the colour defined in RGB The Greencomponent of the colour defined in RGB The Blue component of the colour defined in RGB FPColorToTColor - converts a colour specified as a FPColor to a colour of type TColor Returns the colour specified in FPColor as a colour of type TColor The colour for processing, expressed as a FPColor TColorToFPColor - converts a colour of type TColor to one specified as a FPColor Returns the colour specified as a FPColor c - the supplied colour specified as type TColor Check that the Resource specified for reading or writing is a valid type - result True if it is The Resource type which is to be checked Load the graphic data from a resource identified by the name ResName with the Handle 'Instance' Load graphic data from a resource identified by the integer identifier ResID Loads picture from a named data stream with a specified file extension Finds a graphic class with the named file extension Ext, returning an exception if not found Jpeg - returns a JPEG image

Jpeg - returns a JPEG image

If the contents is not already a JPEG image, the contents are thrown away and a blank JPEG is returned

 PNM - a PortableAnyMapGraphic image

PNM - a PortableAnyMapGraphic image

Reads a PNM image. If it is not a valid PNM image, the contents are thrown away and a blank PNM is generated

 TJPEGImage - a class for handling images stored in JPEG (compressed) format

JPEG images are very commonly used for storing digital photographs. They can represent detailed colour photos using a high degree of compression, resulting in very efficient storage, though with some loss of quality.

The properties CompressionQuality (an integer between 1 and 100, with 100 representing the best quality) and Performance (an enumerated variable with two states: BestQuality or BestSpeed ie compression) can be used to determine the balance between efficiency of storage and quality of picture.

 Initialise the FreePascal Image reader for this image type Finalise the FreePascal Image reader Initialise the FreePascal Image Writer for this image class Determine the compression quality for this image

Extreme compression can lead to loss of quality at the expense of a small file size

Allowed range is 1..100

100 = best quality, 25 = pretty awful

 Is this a grayscale image? Is progressive encoding used for this JPEG? Set for best quality or best speed LoadFromIntfImage - gets Bitmap data from an interface image Finds the type of resource for the bitmap Sets handles for the bitmap and its mask Release the bitmap mask handle Determine whether this instance of the class can read graphic streams Free the colour palette used for this bitmap Release the handle for the bitmap mask Reklease the handle for the colour palette The canvas for the bitmap (ie the actual contents of the picture) The class of stream for saving data Monitoring the progress of drawing a complicated Graphic

TProgressEvent is a generic progress notification event which may be used by TGraphic classes with computationally intensive (slow) operations, such as loading, storing, or transforming image data.

Event params:
Stage Indicates whether this call to the OnProgress event is to prepare for, process, or clean up after a graphic operation. If OnProgress is called at all, the first call for a graphic operation will be with Stage = psStarting, to allow the OnProgress event handler to allocate whatever resources it needs to process subsequent progress notifications. After Stage = psStarting, you are guaranteed that OnProgress will be called again with Stage = psEnding to allow you to free those resources, even if the graphic operation is aborted by an exception. Zero or more calls to OnProgress with Stage = psRunning may occur between the psStarting and psEnding calls.
PercentDone The ratio of work done to work remaining, on a scale of 0 to 100. Values may repeat or even regress (get smaller) in successive calls. PercentDone is usually only a guess, and the guess may be dramatically altered as new information is discovered in decoding the image. The value of this property could usefully be passed to a ProgressBar to show the user how drawing is progressing
RedrawNow Indicates whether the graphic can be/should be redrawn immediately. Useful for showing successive approximations of an image as data is available instead of waiting for all the data to arrive before drawing anything. Since there is no message loop activity during graphic operations, you should call Update to force a control to be redrawn immediately in the OnProgress event handler. Redrawing a graphic when RedrawNow = False could corrupt the image and/or cause exceptions.
Rect Area of image that has changed and needs to be redrawn.
Msg Optional text describing in one or two words what the graphic class is currently working on. Ex: "Loading" "Storing" "Reducing colors". The Msg string can also be empty. Msg strings should be resourced for translation, should not contain trailing periods, and should be used only for display purposes. (Do not use the construct: if Msg = 'Loading' then...)
RGBToColor - assembles the supplied values for Red, Green and Blue into a composite colour LoadCursorFromLazarusResource - loads a named cursor handle from the Lazarus Resource (.LRS) CreateBitmapFromLazarusResource - creates a bitmap image using data read into a stream from a Lazarus Resource (.LRS) InvertColor - returns the complementary colour to the supplied value - helps to produce a 'negative' image DecColor - decrease the component RGBs of a colour by the quantity specified (usually results in a darker colour overall) TCustomBitMap - the base class for TBitmap TPortableAnyMapGraphic - a PAM graphic image TCustomBitmapImage - the base type for TBitmapImage Release the handle for the bitmap mask Free the colour palette used for this bitmap Release the bitmap handle Returns True if bitmap handle is correctly released Release the handle for the bitmap mask Returns True is mask handle was correctly released Release the handle for the colour palette Returns True if palette was correctly released Is the bitmap image empty? Returns True if bitmap is empty Find the format for the pixels (ie the number of bits per pixel) BitmapImage destructor Determine the type of the bitmap handle The canvas for the bitmap (ie the actual contents of the picture) The stream to which the data are to be saved The type of the stream for saving the data The class of stream for saving data Draw the bitmap on the specified Canvas at the specified coordinates The canvas on which the bitmap is to be drawn The rectangular coordinates where the canvas containing the bitmap is located BitMap constructor BitMap constructor. The supplied code can override the definition from ancestor classes BitMap destructor BitMap destructor. The supplied code can override the method defined for ancestor classes Assign: find out about the Source of the call.

Assign: find out about the Source of the call.

If the BitMap data are already in use, the data are shared; if not, a new BitMap is produced

The Source control (usually a Bitmap) for the Assign procedure Releases all the resources used for the image that is being discarded Is a handle allocated for this bitmap? Returns True if a handle is allocated Is a handle allocated for the bitmap mask? Returns True is a mask handle has been allocated Has a colour palette been allocated for this bitmap? Returns True if a palette has been allocated Create an image in the specified rectangle, using the given bitmap and mask handles Checks that the Resource Type specified in the string argument is a valid Lazarus type Returns TRUE if a valid resource type is found The target resource type specified as a string Load a bitmap from the nominated Device The handle for the device from which the bitmap is to be loaded Load a bitmap from a stream The stream from which the bitmap is to be loaded Load a bitmap from a MIME type stream The stream from which the bitmap is to be loaded The MIME type of the stream from which the bitmap is to be loaded Load a bitmap from a Lazarus interface image The Lazarus interface image from which the bitmap is to be loaded Load a bitmap from a XPM file (pixmap) The name of the file from which the bitmap is to be loaded Saves bitmap data to a stream Gets a list of the supported MIME types for the source file Finds the default MIME type Finds the type of resource for the bitmap Finds the available file extensions Masks the bitmap using a transparent colour Sets handles for the bitmap and its mask Reads data from a stream Writes data to a stream Release the bitmap handle, effectively freeing resources Returns True if handle has been correctly released Release the bitmap mask handle Returns True if the Mask handle has been correctly released Release the current palette Returns True if the palette has been correclty released Get the appropriate FPReader for the given file extension Get the appropriate FPWriter for the given file extension Get the default FPReader Get the default FPWriter Read Bitmap data from stream using the FPImage reader Write bitmap data to a native stream Create an interface image The Canvas on which this bitmap is drawn

The Canvas is where all the drawing and painting is performed.

The properties are described in TCanvas

The operating system Handle ssociated with this bitmap The type of system handle The system handle associated with the bitmap mask Whether using monochrome display PixelFormat - number of bits per pixel The transparent colour used for masks etc The mode used for transparency TCursorImage - an Icon to be used to represent a cursor HotSpot - the coordinates of the point to which the cursor refers, and which represents the 'active' position on the current form or canvas IdentEntry - checks that a given Entry exists in a Map of colour names

A list of system Colors is specified as a look-up table of indices (Entry) and names (MapEntry)

This function checks that the value in Entry is within the permitted range, and returns the data pair Value, Name of the corresponding colour in MapEntry.

If Entry is out of range the Result is False

 If Entry is out of the range [0..High(Colours)] the Result is returned as False True if Entry was a valid index into the Colour look-up table Entry - a numeric index into the table of colours MapEntry - the record of Value, Name returned from the look-up table of Colors Returns the inverse of the original colour (ie a 'negative' effect) AColor - the original colour for processing Returns a copy of the original colour, decremented by a specified amount AColor - the original colour for processing AQuantity - the amount by which the colour is to be changed Deprecated - technically a bitmap is created, not loaded Deprecated - technically a bitmap is created, not loaded Returns a Bitmap of type TCustomBitMap AName - name of the bitmap to be created AMinimumClass - optional specifier for class of resource AHandle - optional handle supplied for resource Determine whether this instance of the class can read graphic streams Class of image processor to be used for reading the bitmap Returns True if the supplied class is capable of reading graphic streams EGraphicException - exception handler for error in graphics TSharedRasterImage - a reference counted raster image (may be shared between several controls) IsEmpty - checks if there is actually an image at the reference, and returns True if there is not CreateDefaultHandle - virtual abstract method for creating a default handle for the shared raster image BitmapCanvas - the canvas to be used for painting this bitmap SaveStream - the memory stream to be used for saving this image TRasterImage - base class for a number of graphic controls, including TCustomBitmap and TCustomIcon, which use a raster of dots to display graphic information The Canvas on which this raster image is to be painted HandleAllocated - if True, an Operating System handle has been allocated BitmapHandle - the Handle that has been allocated for the Bitmap MaskHandle - the handle that has been allocated for the Bitmap Mask TransparentColor - the colour used in transparent mode In TransparentMode ir is possible to see the underlying objects through the current image TSharedCustomBitmap - a reference counted base class for TSharedBitmap, TSharedPixmap, TSharedJPEGImage, TSharedPortableNetworkGraphic and TSharedPortableAnyMapGraphic ImageAllocated - returns True if an image has been allocated HandleType the type of Bitmap Handle that has been allocated The Height of the Bitmap The Width of the Bitmap TSharedBitmap - a reference counted Bitmap graphic TSharedPixmap - a reference counted Pixmap graphic TSharedPortableNetworkGraphic - a reference counted PNG Image TSharedPortableAnyMapGraphic - a reference counted shared PAMG TIconImage - a primitive Icon class with handles for the Bitmap, Mask and Palette TSharedIcon - a reference counted shared Icon GetImagesClass - finds which class of icon images is being referenced Clear - remove the icon and free its resources Delete - remove the icon with specified index GetIndex - returns the Index of an image with specified pixel format, height and width ReleaseHandle - returns Bitmap handle to Operating system ReleaseMaskHandle - returns mask Bitmap handle to operating system ReleasePalette - returns Palette handle to operating system UpdateHandles - returns True when Bitmap and Mask handles have been updated Handle - for the Bitmap MaskHandle - Bitmap handle for the Mask Handle for the Palette TCustomIcon - base class for TIcon Add - an Icon formatted as AFormat, with specified Height and Width Clear the Icon and release its resources Delete the indexed Icon Remove the Icon specified by AFormat, AHeight and AWidth GetDescription - find the description for the Icon Aindex - the Index value for the Icon AFormat - the Pixel Format for the Icon AHeight - the height of the Icon AWidth - the width of the Icon SetSize - write the size (width, height) of the Icon GetFileExtensions - returns a list of valid file extensions associated with the Icon LazarusResourceTypeValid - returns True if the specified ResourceType is valid BitmapHandleAllocated - returns True if a Bitmap Handle has been allocated MaskHandleAllocated - returns True if a Mask Bitmap handle has been allocated PaletteAllocated - returns True if a Palette handle has been allocated SetHandles - writes the values of the Bitmap and Mask handles Current - the sequence number of the current Icon Count - the number of references to this Icon TSharedCursorImage - a reference counted shared image to be used for cursors TCursorImageImage - the image for a cursor, stored as an Icon HotSpot - the coordinates of the point to which the cursor refers, and which represents the 'active' position on the current form or canvas The Operating System Handle allocated for this cursor TSharedJpegImage - a reference counted shared image of type JPEG Add a reference to the shared icon Count - returns the number of references to the shared icon