Contour direction of colour glyphs

[William]

Suppose please that there is a monochrome glyph of a zero, with an outer clockwise contour and an inner counterclockwise contour.

Suppose that one wishes to produce a colour glyph, of a red zero filled with yellow.

Regarding the direction of the yellow-filled contour: should it be clockwise or counterclockwise or does the direction not matter?

William Overington

12 November 2013

[Erwin Denissen]

Good question!

The direction does not matter for color glyphs (same goes for composite glyphs) as long as the source/member glyphs have it all set correctly.

[William]

Thank you for replying.

So that means that to make the zero in colour, (by making two copies of the monochrome glyph and deleting a contour from each copy before colourizing each glyph) that I need to change the direction of the remaining contour of one glyph.

This is just a simple example to discuss the issue: the issue arose when I was making a seven-colour design starting from a monochrome line drawing.

I have now tried a test font and used Font Validate... to put it all correct.

William Overington

12 November 2013

[Erwin Denissen]

So that means that to make the zero in colour, (by making two copies of the monochrome glyph and deleting a contour from each copy before colourizing each glyph) that I need to change the direction of the remaining contour of one glyph.

We recommend all simple glyphs have correct contour directions, so if you remove the outer contour, you should adjust the direction of the inner contour.

[William]

Thank you.

William