guess-anchor-from-composites.py

"""
Run in Robofont.
Tries to add anchors to selected glyphs, based on the position of components in relevant glyphs.
This script is not smart enough to distinguish top and bottom anchors (sorry), it must be run again for each target_anchor_name.

Here is a typical process:
- add "_top" to the circumflex glyph (we need at least an anchor as a starting point)
- set target_anchor_name to "top"
- select the base glyphs you want anchored (both base letters and diacritic glyphs)
- run

- add "_bottom" to the cedilla glyph
- set target_anchor_name to "bottom"
- select the base glyphs you want anchored (both base letters and diacritic glyphs)
- run again
- ...

"""


target_anchor_name = "top"
prefered_reference = ["circumflexcmb", "circumflex", "circumflex.cap", "cedillacmb" "cedilla", ]

# ----------------------------------------

def get_matching_anchor_name(anchor_name):
    if anchor_name.startswith("_"):
        return anchor_name[1:]
    else:
        return "_" + anchor_name

def is_anchored(self, glyph):
    if len(glyph.anchors) > 0:
        return True
    else:
        return True

def has_anchor(glyph, anchor_name):
    return anchor_name in (a.name for a in glyph.anchors)

def get_anchor_by_name(glyph, anchor_name):
    for a in glyph.anchors:
        if a.name == anchor_name:
            return a

def has_priority_components(glyph):
    has_targets = [comp.baseGlyph in prefered_reference for comp in glyph.components]
    return sum(has_targets)

def sort_glyph_according_to_priority_components(glyph_list):
    return sorted(references, key=lambda x: has_priority_components(x), reverse=True)





# ----------------------------------------

f = CurrentFont()
sel = f.selectedGlyphNames


reverse_comp_map = {}
for g in f:
    for c in g.components:
        reverse_comp_map.setdefault(c.baseGlyph, []).append(g)
   

for target in sel:
    target_glyph = f[target]
    print(f"Checking {target}")
    references = reverse_comp_map.get(target, [])
    for reference in sort_glyph_according_to_priority_components(references):
        # only look at glyph with 2 components
        # other cases create too many special cases
        if len(reference.components) == 2:
            # print(f"reference found {reference}")
            target_comp = [comp for comp in reference.components if comp.baseGlyph == target]
            if len(target_comp) > 0:
                target_comp = target_comp[0]
            else:
                continue
            other_comp = [comp for comp in reference.components if comp.baseGlyph != target]
            if len(other_comp) > 0:
                other_comp = other_comp[0]
            else:
                continue
            other_glyph = f[other_comp.baseGlyph]
            other_anchor_name = get_matching_anchor_name(target_anchor_name)
            # print(target_anchor_name, other_anchor_name)
            # print(target_glyph, other_glyph)
            if has_anchor(other_glyph, other_anchor_name) and not has_anchor(target_glyph, target_anchor_name):
                other_anchor = get_anchor_by_name(other_glyph, other_anchor_name)
                pos_x = int(other_comp.offset[0] - target_comp.offset[0] + other_anchor.position[0])
                pos_y = int(other_comp.offset[1] - target_comp.offset[1] + other_anchor.position[1])
                print(f"{target_glyph.name}: added anchor {target_anchor_name} <{pos_x} {pos_y}> using {reference.name} as reference")
                target_glyph.appendAnchor(name=target_anchor_name, position=(pos_x, pos_y))

            # elif has_anchor(other_glyph, target_anchor_name) and not has_anchor(target_glyph, other_anchor_name):
            #     target_anchor = get_anchor_by_name(other_glyph, target_anchor_name)
            #     pos_x = int(target_anchor.position[0] - target_comp.offset[0])
            #     pos_y = int(target_anchor.position[1] - target_comp.offset[1])
            #     print(f"{target_glyph.name}: added anchor {other_anchor_name} <{pos_x} {pos_y}> using {reference.name} as reference")
            #     target_glyph.appendAnchor(name=other_anchor_name, position=(pos_x, pos_y))

            
      #