Thank you both for the replies and thanks Marcus for the kind words. In this case, I'll be bevelling just one point in an edge loop of my polygon object so Catmull-Clark wouldn't work. Thanks for the video though: I learned a lot!
It would be great to get math help from the group on drawing points in an arc (Arc B in the above example) in the correct direction between the two points made by the cross product. Thank you! On Tuesday, October 13, 2020 at 5:33:30 AM UTC-7 vince touache wrote: > this is exactly what I had in mind. Catmull-clark will give you a volume > loss, but in this case, it might be just what you're looking for. > > Le mardi 13 octobre 2020 à 02:48:11 UTC-4, Marcus Ottosson a écrit : > >> Just wanted to chime in and say thanks for sharing, love the >> illustrations. >> >> I wonder if catmull-clark is relevant here? I came across this video >> recently which covers implementation in a C-like language (Houdini's VEX). >> >> - https://vimeo.com/457274458 >> >> On Mon, 12 Oct 2020 at 21:59, Kevin C. Burke <kevin...@gmail.com> wrote: >> >>> I have been able to find points A, B, & C in this image: >>> [image: Start_and_End_Angle.jpg] >>> >>> Here is my pymel that creates locators for V1, V2, & V3, then solves for >>> A, B, & C.: >>> import pymel.core as pm,math >>> import pymel.core.datatypes as dt >>> >>> r = 1.5 #radius >>> V1 = dt.Vector(1, 2, 0) >>> V2 = dt.Vector(2, 6, 0) >>> V3 = dt.Vector(7, 7, 0) >>> V1L = pm.spaceLocator( p=V1, n="v1", a=True ) >>> V2L = pm.spaceLocator( p=V2, n="v2", a=True ) >>> V3L = pm.spaceLocator( p=V3, n="v3", a=True ) >>> a = V2-V1 >>> b = V2-V3 >>> a.normalize() >>> b.normalize() >>> halfang = math.acos((a.dot(b)))/2 >>> ab = (a+b)/2 >>> ab.normalize() >>> A = V2 - r/math.tan(halfang)*a; >>> B = V2 - r/math.tan(halfang)*b; >>> C = V2 - r / math.sin(halfang) * ab >>> >>> AL = pm.circle( c=A, r=0.3, nr=(0, 0, 1), n="A" ) >>> BL = pm.circle( c=B, r=0.3, nr=(0, 0, 1), n="B" ) >>> CL = pm.circle( c=C, r=0.3, nr=(0, 0, 1), n="C" ) >>> >>> I am seeking help in determining the positions of a specified number of >>> points in the arc labeled 'Arc B' between A & C. >>> >>> >>> On Monday, October 12, 2020 at 11:04:34 AM UTC-7 Kevin C. Burke wrote: >>> >>>> Hello, >>>> I'd like to procedurally bevel an edge loop for a polygon object plugin >>>> that I am making. I am seeking help in coding an algorithm that does this >>>> using Python (not using any API method like polyBevel >>>> <https://help.autodesk.com/cloudhelp/2017/ENU/Maya-Tech-Docs/PyMel/generated/functions/pymel.core.modeling/pymel.core.modeling.polyBevel.html?highlight=polybevel> >>>> ). >>>> >>>> So far in my research, it appears to be a matter of mathematically >>>> generating an arc of points between two points [P1, P2] based on their >>>> distance from a third angular point [P] and a radius. >>>> [image: B1ifD.gif] >>>> >>>> [image: Bevel.gif] >>>> >>>> I found this post from Stack Overflow >>>> <https://stackoverflow.com/questions/24771828/algorithm-for-creating-rounded-corners-in-a-polygon/24780108#24780108> >>>> >>>> about rounding corners using the C# & math. In an attempt to understand >>>> it, >>>> I created this <https://codepen.io/blastframe/pen/gOMbEQj>, my >>>> translation to Javascript & HTML Canvas. I'm unable to get the arc of >>>> points to meet at the right positions consistently though as I do not >>>> entirely understand the math. >>>> >>>> Can anyone provide guidance for generating this arc of points based on >>>> three points please? Thank you! >>>> >>> -- >>> You received this message because you are subscribed to the Google >>> Groups "Python Programming for Autodesk Maya" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to python_inside_m...@googlegroups.com. >>> To view this discussion on the web visit >>> https://groups.google.com/d/msgid/python_inside_maya/fe4ad6be-9f0c-418f-99f8-3968f6a6e0dan%40googlegroups.com >>> >>> <https://groups.google.com/d/msgid/python_inside_maya/fe4ad6be-9f0c-418f-99f8-3968f6a6e0dan%40googlegroups.com?utm_medium=email&utm_source=footer> >>> . >>> >> -- You received this message because you are subscribed to the Google Groups "Python Programming for Autodesk Maya" group. To unsubscribe from this group and stop receiving emails from it, send an email to python_inside_maya+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/python_inside_maya/825b3a33-8514-4d51-9bc4-03d6e27773acn%40googlegroups.com.
