But you should check that your font passes those tests that examine the glyphs for required features, and several tests that look for optional but commonly-expected behavior.Several of the other tests provide feedback and guidance to you during the design process, and are worth exploring for that reason. This test makes sure that all of the points in each glyph (including both on-curve points and control points) have integer coordinates.When you click the OK button, the tool will examine all of the selected glyphs, and report any problems it finds in a dialog box.
The first looks for points at the extrema — that is, the uppermost point, lowest point, and leftmost and rightmost points of the glyph.
Modern font formats strongly suggest that each path have a point at each of its horizontal and vertical extrema; this makes life easier when the font is rendered on screen or on the page. The second test is a sanity check on the number of points within any one glyph.
Font Forge’s default value for this check is 1,500 points, which is the value suggested by the Post Script documentation, and it is good enough for almost all fonts.
The tests listed above will ensure that your font installs and renders correctly according to the rules set out by the various font formats, but there are a handful of others tests you should consider adding — especially at the end of the design process — simply because they check for common conventions followed by most modern typography. This test will look for control points lying beyond the endpoints of the curve segment on which they reside.
There is rarely a reason that a control point should lie outside of the curve, so these instances usually signify accidents.