question: contours and components inside some rect

RafaŁ Buchner

Small scripting question. (Hopefully this heavy rain of the questions will end up at some point)

What is the easiest way to check if some contour or component in the glyph is inside some abstract rectangle?

I have coordinates and size of the rectangle. Now I would like to check out if the objects shapes are inside it.

Determining if points are inside the rect is easy. But when it comes to components and contours: something that have lines and curves is really hard.
I've been trying to creating the function, that would take the contour or component as an argument, and return True or False value. (True if at least part of the shape is inside the rectangle). I've been trying to do it with the booleanOperators and I failed.

Any help?

By the way, I'm thinking that it could be a bug:

from mojo.tools import union
g = CurrentGlyph()
union(g, g[0], g[1], roundCoordinates=None)

gives

Traceback (most recent call last):
  File "<untitled>", line 3, in <module>
  File "/Applications/RoboFont3.app/Contents/Resources/lib/python3.6/mojo/tools.py", line 84, in union
  File "/Applications/RoboFont3.app/Contents/Resources/lib/python3.6/mojo/tools.py", line 84, in <listcomp>
  File "/Applications/RoboFont3.app/Contents/Resources/lib/python3.6/fontParts/base/base.py", line 255, in naked
  File "/Applications/RoboFont3.app/Contents/Resources/lib/python3.6/fontParts/base/base.py", line 232, in raiseNotImplementedError
NotImplementedError: The RSegment subclass does not implement this method.

frederik

Two circular components could have overlapping bounds but have no visual overlap. The only option to check is to perform a remove overlap and look for changes. This means for components you have to decompose first.

good luck!

bahman

This post is deleted!

gferreira

@RafaŁ-Buchner you’re right :) better to use the boolean glyph method then.

RafaŁ Buchner

@gferreira Hmm, I think it doesn't need to be true (Let's say that we have the shape of the glyph "C". The rect is inside of the letter: then it doesn't work)

RafaŁ Buchner

Great! Thanks for the help!

frederik

oke, idd much simpler :)

also take a look at fontTools arrayTools: sectRect, pointsInRect, pointInRect

gferreira

@frederik true! but in this case we know that the frame is a rectangle – so checking the bounds works too. here’s a proof:

g = CurrentGlyph()

x, y, w, h = 206, -218, 358, 392
box = x, y, x+w, y+h

translate(230, 270)

for contour in g.contours:
    color = (0, 1, 0) if overlaps(contour, box) else (1, 0, 0)
    fill(*color)
    B = BezierPath()
    contour.draw(B)
    drawPath(B)

stroke(0)
strokeWidth(10)
fill(None)
drawGlyph(g)

stroke(0, 0, 1)
rect(x, y, w, h)

frederik

Two circular components could have overlapping bounds but have no visual overlap. The only option to check is to perform a remove overlap and look for changes. This means for components you have to decompose first.

good luck!

gferreira

regarding union: you need to use a glyph or a list of contours:

from mojo.tools import union
g = CurrentGlyph()
union(g, [g[0]], [g[1]], roundCoordinates=None)

gferreira

you can use the bounds of the contours or components to check if they overlap with the rectangle:

def overlaps(contourOrComponent, box):

    left, bottom, right, top = contourOrComponent.bounds
    rectLeft, rectBottom, rectRight, rectTop = box

    xOverlap = right > rectLeft and left < rectRight
    yOverlap = top > rectBottom and bottom < rectTop

    if xOverlap and yOverlap:
        return True
    else:
        return False

x, y, w, h = 118, 246, 104, 402
box = x, y, x+w, y+h

g = CurrentGlyph()

for c in g.contours:
    print(overlaps(c, box), c)

for c in g.components:
    print(overlaps(c, box), c)

SOLVED question: contours and components inside some rect