Declaration

type
  TCustomBitmap32 = class(TCustomMap)
    ...
  TCustomBitmap32Class = class of TCustomBitmap32;

Description

TCustomBitmap32 is the primary 2D image data container in Graphics32. It extends TCustomMap with 32-bit ARGB pixel buffer management, hardware-abstracted rendering backends (TCustomBackend), spatial clipping (ClipRect), drawing modes (DrawMode, CombineMode), alpha blending (MasterAlpha), and customizable pixel resamplers (TCustomResampler).

Pixel elements are represented as 32-bit ARGB colors (TColor32). TCustomBitmap32 provides extensive accessor methods for reading and writing pixels at integer, fixed-point (TFixed), or single-precision floating-point (TFloat) sub-pixel coordinates.

Derived Class: TBitmap32

Constructors

Name	Description
Create	Initializes a new TCustomBitmap32 instance with default or custom backend and dimensions.

Methods

General & Lifecycle

Name	Description
Assign	Copies pixel buffer and properties from another persistent object or bitmap.
BeginMeasuring	Begins area change measurement and bounding box calculation.
BoundsRect	Returns a TRect representing the bitmap dimensions (0, 0, Width, Height).
Changed	Triggers update notifications for the entire bitmap or a specified sub-rectangle.
Clear	Clears the bitmap pixel buffer to zero (clNone32) or a specified TColor32 fill color.
CopyMapTo	Copies raw map dimensions and pixel data to a target TCustomBitmap32.
Delete	Resets bitmap dimensions to zero and releases buffer memory.
Empty	Returns True if the bitmap has zero width or height.
EndMeasuring	Concludes area change measurement.
GetPlatformBackendClass	Class method returning the default platform backend class.
PropertyChanged	Notifies the bitmap and backend that a property has changed.
ReleaseBackend	Detaches and returns the active backend instance without destroying it.
ResetClipRect	Resets ClipRect to cover the full bitmap bounds (0, 0, Width, Height).

Stream & File I/O

Name	Description
LoadFromFile	Loads bitmap data from a file on disk.
LoadFromResourceID	Loads bitmap data from an embedded resource by integer ID.
LoadFromResourceName	Loads bitmap data from an embedded resource by string name.
LoadFromStream	Loads bitmap data from a stream.
SaveToFile	Saves bitmap data to a file on disk in BMP/DIB format.
SaveToStream	Saves bitmap data to a stream in BMP/DIB format.

Blitting & Alpha Operations

Name	Description
Draw	Draws a source bitmap or sub-rectangle onto this bitmap.
DrawTo	Draws this bitmap or a sub-rectangle onto a target destination bitmap.
ResetAlpha	Resets alpha values of all pixels to $FF (opaque) or a specified alpha component.
SetPixelT	Sets a pixel with alpha blending (DrawMode / CombineMode).
SetPixelTS	Sets a pixel with alpha blending and boundary clipping.

Lines & Drawing Primitives

Name	Description
HorzLine	Draws fast horizontal 1-pixel wide lines across integer or fixed-point coordinates with optional boundary clipping, alpha blending, and stippling.
VertLine	Draws fast vertical 1-pixel wide lines across integer or fixed-point coordinates with optional boundary clipping, alpha blending, and stippling.
Line	Draws 1-pixel wide line segments between specified coordinates using integer, fixed-point, or floating-point positioning with optional clipping, blending, anti-aliasing, and stippling.
MoveTo	Sets current pen position for subsequent LineTo drawing operations using integer, fixed-point, or floating-point coordinates.
LineTo	Draws 1-pixel wide line segments from current pen position to target coordinates using integer, fixed-point, or floating-point positioning, updating pen position afterwards.

Rectangles & Shapes

Name	Description
FillRect	Fills a rectangular area with a specified 32-bit ARGB color using integer coordinates or TRect bounds, supporting optional boundary clipping and alpha blending.
FrameRect	Draws 1-pixel wide rectangular outline frames around specified coordinates or TRect bounds with optional clipping, alpha blending, and stippling.
RaiseRectTS	Draws a 3D bevelled button/panel edge.

Transformations

Name	Description
Roll	Scrolls/shifts pixel contents horizontally and vertically with optional background fill.
FlipHorz	Flips pixel contents horizontally (left to right).
FlipVert	Flips pixel contents vertically (top to bottom).
Rotate90	Rotates bitmap contents 90 degrees clockwise.
Rotate180	Rotates bitmap contents 180 degrees.
Rotate270	Rotates bitmap contents 270 degrees clockwise (90 degrees counter-clockwise).

Stipple Methods

Name	Description
SetStipple	Sets custom stipple color array pattern.
AdvanceStippleCounter	Advances stipple counter position by specified distance in pixels.
GetStippleColor	Evaluates and returns current stipple color.

Properties

Pixel Accessors

Name	Type	Scope	Description
Pixel	TColor32	Public	Indexed pixel access properties for reading and writing 32-bit ARGB pixel values across integer, fixed-point, and floating-point coordinates.

Pen & Stipple Properties

Name	Type	Scope	Description
PenColor	TColor32	Public	Color used for pen drawing operations (MoveTo, LineTo).
PenPos	TPoint	Public	Current integer pen coordinate position.
PenPosF	TFixedPoint	Public	Current fixed-point pen coordinate position.
StippleCounter	Single	Public	Current phase position index along stipple pattern array.
StippleStep	Single	Public	Step distance increment for stipple pattern evaluation.

Buffer & Backend Properties

Name	Type	Scope	Description
Backend	TCustomBackend	Public	Active rendering surface backend instance.
Bits	PColor32Array	Public	Pointer to contiguous raw 32-bit ARGB pixel memory buffer.
ClipRect	TRect	Public	Clipping rectangle restricting pixel modifications.
Clipping	Boolean	Public	Read-only flag indicating if ClipRect active region is smaller than full bitmap dimensions.
MeasuringMode	Boolean	Public	Indicates whether area change measurement is active.
PixelPtr	PColor32	Public	Pointer to specific pixel at integer coordinates [X, Y].
ScanLine	PColor32Array	Public	Pointer to starting pixel memory location for scanline row [Y].

Drawing Modes & Resampling

Name	Type	Scope	Description
CombineMode	TCombineMode	Published	Pixel combination mode (cmBlend, cmMerge).
DrawMode	TDrawMode	Published	Draw mode (dmOpaque, dmBlend, dmCustom).
MasterAlpha	Cardinal	Published	Global alpha scaling factor (0 to 255) applied to draw operations.
OuterColor	TColor32	Published	Color returned when sampling outside bitmap bounds in safe/transparent mode.
Resampler	TCustomResampler	Published	Active resampler engine instance for sub-pixel stretching and sampling.
ResamplerClassName	string	Published	Class name string of current resampler engine.
WrapMode	TWrapMode	Published	Boundary wrapping mode (wmClamp, wmRepeat, wmMirror).

Events

Name	Type	Description
OnAreaChanged	TAreaChangedEvent	Fired when a specific sub-rectangle region of pixel memory is updated.
OnPixelCombine	TPixelCombineEvent	Custom pixel combination callback event when DrawMode = dmCustom.