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Convert notes into blockquotes

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James Gregory 2013-12-31 11:06:31 +11:00
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@ -123,9 +123,17 @@ orientations are distinguished by which coordinate forms the major axis
and by whether each of X and Y increases or decreases from the line
start to the line end.
------------------- ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
![](images/i.jpg) *A moment of thought will show, however, that four of the line orientations are redundant. Each of the four orientations for which **DeltaY**, the Y component of the line, is less than 0 (that is, for which the line start Y coordinate is greater than the line end Y coordinate) can be transformed into one of the four orientations for which the line start Y coordinate is less than the line end Y coordinate simply by reversing the line start and end coordinates, so that the line is drawn in the other direction. **EVGALine** does this by swapping (X0,Y0) (the line start coordinates) with (X1,Y1) (the line end coordinates) whenever Y0 is greater than Y1.*
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> ![](images/i.jpg)
> A moment of thought will show, however, that four of the line
> orientations are redundant. Each of the four orientations for which
> **DeltaY**, the Y component of the line, is less than 0 (that is, for
> which the line start Y coordinate is greater than the line end Y
> coordinate) can be transformed into one of the four orientations for
> which the line start Y coordinate is less than the line end Y coordinate
> simply by reversing the line start and end coordinates, so that the line
> is drawn in the other direction. **EVGALine** does this by swapping
> (X0,Y0) (the line start coordinates) with (X1,Y1) (the line end
> coordinates) whenever Y0 is greater than Y1.
This accomplished, **EVGALine** must still distinguish among the four
remaining line orientations. Those four orientations form two major