Shear Scale Parallel?


#1

here some simple or maybe not so simple task :wink:

i want to get the circle on the left side scaled or sheared however, like on the right side.
any idea how that could be done?

to manage this i had to align it first then scale 1d along x to the new width and then to shear it 45° not sure if thats correct now its looks slightly unproportional, can also be imaginative. but is there an easier way to transform it with 4 points for example? cage edit brought me there but it rebuilds the curve which is not so severe but that only works when i use a new surface square as a control object. if i use a square curve it deforms the circle badly after moving.

so far all steps are a bit unhandy i might say…
any suggestions?


(Pascal Golay) #2

Hi Richard - try - Orient with Scale=1D, snapping to opposite corners of the square first and the skewed square second.

Nope that does not do it…

Make a 4 point surface (SrfPt) on the square corners and use it to CageEdit the circle over to the skewed shape - or make two surfaces and FlowAlongSrf

-Pascal


#3

yes i tried that, but its a bit complicated and it rebuilds the curve. flow along surface is a bit faster in the workflow it seems but i still have to make 2 surfaces and the curve also gets rebuild.

so far copying the circle with the square as a reference to the end position scaling 1d and shearing it to the new angle has proven the best option because it keeps the control points in tact. but its still complicated.

but if you ran out of options than thats it?


#4

Erm… I think shear might work?

Have a look at this: http://screencast-o-matic.com/watch/cDXrYlQfAX

I drew a regular ellipse to check that it looked ok.

Seems legit… I think it’s the foreshortening in the front to back but the up down isn’t compressed so it looks odd.

Andy


#5

yes so it might be optical. but its still a bit complicated and i hoped for something faster.
but ok then.

thanks to both of you


#6

Sorry Richard, it’s getting late here. I didn’t read your post fully, I can see you’d already done what I did.


#7

If i was doing this, I would first make a 3d cube and do my circle on the front face …

Get volume centre of cube and array polar the circle . If you do o 4 times at 360º delete the back 2.

Rotate cube and circles to match your image, I did 22.5º for this one.

Take your side circle and set points, I used Y

Cheers,

«Randy


#8

no worries thanks for helping anyway, at least you found the best solution as i did in matter of quality.
its slightly faster with 2 surfaces as pascal suggested but it rebuilds… so far no better solution :slight_smile:

i had thought about that. but you would have to shear the 3d cube first to get the same optics as shown above.
all in all it would be even more work… it would be usable if i´d had an isometric cube for example but even then for what i am trying only a circle will not do, i need different objects… so no good… but thanks anyway. :wink:


#9

I did the cube, exploded and then deleted all sides not need. The right side I rotated from centre 45º and then flattened the side and circle with SetPoints. then from centre with side and circle selected shear both.


#10

Yeah, I wasn’t sure about the look of it so did it again with an offset square which touched the quads of the circle. That overlays perfectly with the control points of the ellipse you’re left with.

What perplexes me is I did this years ago when I first started using AutoCAD back in the early 90’s but I couldn’t work out how to draw it without skewing it now. The best I could come up with was blending curves from the offset box:

http://screencast-o-matic.com/watch/cDXr3FQfEq

Good one though :slight_smile:


(Pascal Golay) #11

Hi Richard - if you use the square surface to CageEdit you can set ‘PreserveStructure=Yes’.

-Pascal


#12

thanks Randy but its just way too complicated.

but if you have to make something more complex than a circle that might be a bit of a pain.

ah yes true, so thats at least an option now.
maybe flow could get that implemented either.


(Pascal Golay) #13

Yep, it’s there in V6/WIP.

-Pascal


#14

Just because I am curious … all 2D . Square 10 mm with grid snap. I brought your original image for reference. Cube on the right is just for scale. Circle from centre of square. Then mirror to get right-side objects to adjust like your drawing. Total time so far less than ½ minute.

Select right square and circle, move gumboil to midpoint on the left side of cube.

Scale 1D

Shear

Total time less than 2 minutes, probably closer to 1, including Picture frame and Orient 2 to scale image for reference.

Just checking with another object …

Cheers!


#15

yup thats one of the options as discussed long ago :wink:


#16

Correct.

I also think the circle looked odd, but the drawing i did looked correct to my eyes. That is why I wanted to try myself to see.


#19

didnt get a glimpse at it yet, but if you tell me that shear has a scale 1d implemented?
which would do this kinda job even faster i would be all eyes for it, rather sooner than later.

not sure why you think this is important here but suit yourself :slight_smile: