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2.2.1 Basic Incremental Algorithm

Cf. [FvDFH90, 3.2.1].

A better way to do this is recursively: The points on the line $ y=k\,x+d$ for $ x_i:=x_0+i$ are given inductively by

$\displaystyle y_{i+1}:=y_i+k. $

Figure: Basic incremental algorithm for scan converting lines
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This way we get rid of the multiplication, but we still have to apply $ \operatorname{ROUND}$. Note however, that successive addition of a real number can lead to a cumulative error buildup. Here, this can usually be ignored.

next up previous contents index
Next: 2.2.2 Midpoint Line Algorithm Up: 2.2 Scan Converting Lines Previous: 2.2 Scan Converting Lines
Andreas Kriegl 2003-07-23