Overlapping gap between character space and regular character when using negative tracking

Danielillo

Working in Fontlab, I use the space as a character, a kind of four-line staff. When creating the OTT font it works perfectly in any program. But when exporting a PDF, only if the tracking is negative or the kerning is in optical mode, the overlap between the space character and a normal character is negative.

In the image, the red and black lines are the space character (I used different colors to show that there is no error). In the left part of the image, the character space (red and black) has a negative tracking and works fine. The letter N has tracking 0.

If the space character is next to a normal character, the N in the right part of the image, when this character has negative  tracking or kerning it shows the overlay in white (negative), and only the three bottom lines...

This does not happen between "normal" characters or between spaces, only when it's space + character.

This is the space character in Fontlab, overlaps are already removed:

I think I've tried everything, I guess it has something to do with the space being negative and a character being positive. Is there any way to solve it?

Well, I found the error, I don't know how to delete the question 

😉 😅

steven

It is caused by the inconsistency of the path directions of the three left and right lines. Try to correct the path direction.