User Guide

Hinting

493

Each of these hints should, however, work only on part of the outline:

Hin ts set#1

STARTPOINT

6677

10 10

11 11

12 12

13 13

14 14

15 15

STARTPOINT

Hints set#2

As you can see, we have two hint sets and three outline segments: from

point 1 to point 4, from point 5 to point 12 and from point 13 to point 15.

So we must switch active hint sets as the rasterizer proceeds along the

contour to match the part of the outline that the hint sets apply to. We

need to have some program that will switch off the right hint in segment 2

(after the rasterizer has passed point 3, where the right hint applies and

before it gets to point 5 where the left hint applies) and switch it back on in

segment 3 (before it gets to point 13 where the right hint applies again).

The same program should switch on the left hint in segment 2 and switch it

off again in segment 3. This way only one of the two hints is active at any

one time.