iVariance

Amount of width change that is tolerated between adjacent line slices. If LINE_USE_DPI is set in uFlags, units are in thousandths of an inch, otherwise units are in pixels. This parameter is valid only if LINE_USE_VARIANCE is set in uFlags. For example, the following horizontal line is 30 pixels in length (X represents a pixel)

XXXXXXXXXX
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
XXXXXXXXXX
XXXXXXXXXX 

If iVariance is 2 pixels (i.e. tolerate width changes of 2 pixels or less), the first 10 columns and the last 10 columns of the line will be removed. The middle 10 columns will be unchanged. This helps preserve characters that intersect a line that is being removed.