compas-dev/compas

Transformation of geometry

Licini opened this issue · 4 comments

from compas.geometry import Box
from compas.geometry import Scale

box = Box.from_width_height_depth(1, 1, 1)
print(box)

box.transform(Scale.from_factors([2, 2, 2]))
print(box)

box.scale(2)
print(box)

from compas.geometry import Sphere

sphere = Sphere(1)
print(sphere)

sphere.transform(Scale.from_factors([2, 2, 2]))
print(sphere)

sphere.scale(2)
print(sphere)
Box(xsize=1.0, ysize=1.0, zsize=1.0, frame=Frame(point=Point(x=0.0, y=0.0, z=0.0), xaxis=Vector(x=1.0, y=0.0, z=0.0), yaxis=Vector(x=0.0, y=1.0, z=0.0)))
Box(xsize=1.0, ysize=1.0, zsize=1.0, frame=Frame(point=Point(x=0.0, y=0.0, z=0.0), xaxis=Vector(x=1.0, y=0.0, z=0.0), yaxis=Vector(x=0.0, y=1.0, z=0.0)))
Box(xsize=2.0, ysize=2.0, zsize=2.0, frame=Frame(point=Point(x=0.0, y=0.0, z=0.0), xaxis=Vector(x=1.0, y=0.0, z=0.0), yaxis=Vector(x=0.0, y=1.0, z=0.0)))
Sphere(radius=1.0, frame=Frame(point=Point(x=0.0, y=0.0, z=0.0), xaxis=Vector(x=1.0, y=0.0, z=0.0), yaxis=Vector(x=0.0, y=1.0, z=0.0)))
Sphere(radius=1.0, frame=Frame(point=Point(x=0.0, y=0.0, z=0.0), xaxis=Vector(x=1.0, y=0.0, z=0.0), yaxis=Vector(x=0.0, y=1.0, z=0.0)))
Sphere(radius=2.0, frame=Frame(point=Point(x=0.0, y=0.0, z=0.0), xaxis=Vector(x=1.0, y=0.0, z=0.0), yaxis=Vector(x=0.0, y=1.0, z=0.0)))

We need to be careful about this... I understand this is tricky because of non-uniform scale, maybe there should a some kind of warning saying the Scale transform might not work as expected

It's kind of broken now, right? scale vs scaled do different things also

yes, scaled, translated, rotated don't use the corresponding in-place version but rather a modified version of transformed.

i can fix this...

i can also bring back the scale part of the regular transform. it was thrown out because of the expensive decomposition of the transformation matrix to get the scale components and avoid non-uniform scaling, but i can try to do that differently...