Maintain the volume of an object

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Karl Toon
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Maintain the volume of an object

Post by Karl Toon »

Hi,
Am I missing something? I have a layer with a circle in it and I want to use squash and stretch. I should be able to grab one of the top or side handles with the transform tool and ALT and maintain the volume of the object. This isn't working for me and the volume of the object increases? Anyone any ideas other than manually changing the x and y scales? Thanx. :?
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Maestral
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Re: Maintain the volume of an object

Post by Maestral »

Could be several things...

the placing of the origin point is a referent point
curvature is not re-calculated but adjusted if not entirely preserved

... and above all, deformation as described, it's proportional and 'generic' transformation not exactly the same as s&s within Bone cons. pannel (which is also 'generic')
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hayasidist
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Re: Maintain the volume of an object

Post by hayasidist »

manual is wrong .. it's shift (not alt) with one of the edge bounding box control points selected to scale a layer preserving volume (although as Maestral points out, it's actually keeping layer_scale_x * layer_scale_y constant, not actually preserving shape area.)
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slowtiger
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Re: Maintain the volume of an object

Post by slowtiger »

Select transform tool, grab side/middle handle (NOT corner handle), press alt, drag.
Shift seems to do nothing (in v11.5).
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synthsin75
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Re: Maintain the volume of an object

Post by synthsin75 »

slowtiger wrote: Sat Sep 26, 2020 2:08 pm Select transform tool, grab side/middle handle (NOT corner handle), press alt, drag.
Shift seems to do nothing (in v11.5).
In v12, alt is uniform scaling.
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Greenlaw
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Re: Maintain the volume of an object

Post by Greenlaw »

Here's the list of Transform Shape shortcuts that work for me in Moho 12.5:

- Drag from corner, scales non-uniformly from opposite corner.
- Press Alt while dragging from corner, scales uniformly from center.
- Press Alt and then Shift while dragging from corner, scales non-uniformly from center.

- Drag from side, scales non-uniformly from opposite side.
- Press Alt just while dragging from side, scales symmetrically from center.
- Press Alt and then Shift while dragging from side, scales while maintaining volume (i.e., squash and stretch.)

Hope this helps.
Last edited by Greenlaw on Sun Sep 27, 2020 2:51 am, edited 2 times in total.
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Greenlaw
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Re: Maintain the volume of an object

Post by Greenlaw »

Note that Transform Layer behaves differently:

- Drag from corner, scales uniformly from origin
- Drag from side, scales symmetrically from origin
- Press Shift while dragging from corner, scales non-uniformly from origin
- Press Shift while dragging side maintains volume (i.e., squash and stretch.)

With layers, you can't scale from the opposite corner or side because a layer always scales from its origin. So, by default, it may appear to scale from center (assuming your shape is centered,) but if you move the origin, the layer will scale from the new origin position.
Last edited by Greenlaw on Sun Sep 27, 2020 2:53 am, edited 5 times in total.
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Greenlaw
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Re: Maintain the volume of an object

Post by Greenlaw »

Or...

You can bind the shape or layer to a bone and use the bone to give it a 'squash and stretch' effect.

To do this, select the Bone with the Select Bone tool and then open the Bone Constraints panel. Next, enable Squash And Stretch Scaling. To see the effect, you need to be on an animation frame (not frame zero.) In this case, the scaling occurs from the base of the bone.
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