Naming conventions

General

Graphics32 follows standard Delphi/FPC identifier naming practices:

Category	Prefix	Example
Classes	T	TBitmap32, TImage32, TCustomSampler
Interfaces	I	IBackend, INotify
Types / Records	T	TColor32, TFloatPoint, TRect
Color Constants	cl	clWhite32, clRed32
Global Functions	PascalCase	Color32, RedComponent, Intensity

Line and Pixel methods

The TBitmap32 class provides a large number of methods for single pixel access and single pixel width line drawing. While the prefix of these methods indicate what they do (draw a line, access a pixel, etc.), the postfix denotes how they behave. The methods can include one or more of the following postfixes:

Postfix	Name	Description	Sample (magnified x4)	Examples
(none)		Methods without modifiers offer maximum performance. Lines and pixels are rendered without anti-aliasing and without color blending. No clipping is performed so coordinates are expected to be within bitmap boundaries. Out of bounds coordinates can cause access violations and memory overwrites.		Line HorzLine Pixel FillRect
S	Safe	Clipping is performed when coordinates extend beyond bitmap boundaries. This modifier can be combined with any one of the anti-aliasing or transparent modifiers below (T, A, X or F) and also with the stippling (P) modifier.		LineS LineToS PixelS
T	Transparent	Semi-transparent pixels are merged onto the background image (though still without anti-aliasing).		LineTS LineToTS FillRectTS
A	Anti-aliased	Uses a modified version of Bresenham’s algorithm known as Wu’s antialiasing.		LineA LineAS
X	Fixed	Coordinates are in fixed point (TFixed) format. These methods also employ a more sophisticated anti-aliasing algorithm than that used in the ‘A’ methods above.		LineX LineXS PixelXS
F	Float	Coordinates are in floating point (TFloat) format. These methods employ the same anti-aliasing algorithm used in the ‘X’ methods.		LineFS PixelFS
P	Stippling	Lines are drawn using a stippling pattern. This modifier must be combined with either the ‘X’ or ‘F’ modifiers above.		LineFSP LineXSP

Note

For lines, all the methods listed above draw line segments that are a single pixel wide. To draw thicker lines, see the Polyline and PolyPolyline functions in the GR32_Polygons unit. Those functions also produce better anti-aliased blending over fully transparent backgrounds (when compared with X & F modified methods above).

Blend functions

Most blend functions are named using a scheme that clearly identify how they operate:

Name	Example	Meaning
*Reg*	BlendReg	The result foreground color is returned as the function Result.
*Mem*	BlendMem	The result foreground color is returned in the F parameter.
Ex*	MergeRegEx	The the foreground alpha is scaled with a master alpha value.
*Mems*	BlendMems	Apply a single foreground color onto an array of background colors.
*Line*	MergeLine	Apply an array of foreground colors onto an array of background colors.
*RGB*	BlendMemRGB	Operate independently on each color channel using separate alpha values.
*Line1*	MergeLine1	Deprecated. Same as *Mems*.