ChartDirector 6.0 (C++ Edition)

DrawArea.rAffineTransform


Usage

void rAffineTransform(double a, double b, double c, double d, double e, double f, int bgColor = 0xffffff, int filter = LinearFilter, double blur = 1);

Description

Perform reverse affine transformation on the drawing surface.

A reverse affine transformation is an operation where every pixel is copied from another pixel according to the formula.

xSrc = a * xDest + b * yDest + c
ySrc = d * xDest + e * yDest + f

where (xDest, yDest) is a destination pixel, and (xSrc, ySrc) is where it should come from.

Many graphics operation, such as translation, rotation, and resizing, can be considered as a special case of reverse affine transformation.

Arguments

ArgumentDefaultDescription
a(Mandatory)The parameter 'a' in the coordinate transformation formula "xSrc = a * xDest + b * yDest + c".
b(Mandatory)The parameter 'b' in the coordinate transformation formula "xSrc = a * xDest + b * yDest + c".
c(Mandatory)The parameter 'c' in the coordinate transformation formula "xSrc = a * xDest + b * yDest + c".
d(Mandatory)The parameter 'd' in the coordinate transformation formula "ySrc = d * xDest + e * yDest + f".
e(Mandatory)The parameter 'e' in the coordinate transformation formula "ySrc = d * xDest + e * yDest + f".
f(Mandatory)The parameter 'f' in the coordinate transformation formula "ySrc = d * xDest + e * yDest + f".
bgColorFFFFFFThe background color used to fill destination pixels that are not mapped to any source pixels.
filterLinearFilterThe filter to use for re-sampling.
blur1The blur factor to use for re-sampling.

Return Value

None