Hello FreeCAD community,
I'm in the PartDesign module and want to mirror a pocket along the x AND the y axis at the same time (point reflection through the center)
PartMirror doesn't have that option so I tried Multitranform. But Multitranform keeps the in-between steps. So at the end I have three pockets: The original, the one mirrored around X and the one mirrored around XY.
What can I do?
Thanks
Thomas
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[Solved] PartDesign: Mirror along X and Y / Point Reflection / Multitranform but only keep result
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[Solved] PartDesign: Mirror along X and Y / Point Reflection / Multitranform but only keep result
Last edited by thomas-huber on Wed May 18, 2022 12:10 pm, edited 2 times in total.
Re: PartDesign: Mirror along X and Y / Point Reflection / Multitranform but only keep result
Hmm...it is probably obvious, but I've not had much coffee as yet today...thomas-huber wrote: ↑Wed May 18, 2022 11:44 am Hello FreeCAD community,
I'm in the PartDesign module and want to mirror a pocket along the x AND the y axis at the same time (point reflection through the center)
PartMirror doesn't have that option so I tried Multitranform. But Multitranform keeps the in-between steps. So at the and I have three pockets: The original, the one mirrored around X and the one mirrored around XY.
What can I do?
...
I'm having trouble picturing what exactly "point reflection through center" means.
Can you provide an image (hand drawing, or link to something) that is an example...
Star Trek II: The Wrath of Khan: Spock: "...His pattern indicates two-dimensional thinking."
Re: PartDesign: Mirror along X and Y / Point Reflection / Multitranform but only keep result
Create a reference plane angled 45', and mirror the pocket to that?
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Re: PartDesign: Mirror along X and Y / Point Reflection / Multitranform but only keep result
I mean something like this:
I found a solution myself in the meanwhile:
I used the PolarPattern and just rotated the pocket around the center. Still I'm interested if this is the common approach for this
I found a solution myself in the meanwhile:
I used the PolarPattern and just rotated the pocket around the center. Still I'm interested if this is the common approach for this
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Re: [Solved] PartDesign: Mirror along X and Y / Point Reflection / Multitranform but only keep result
Central symmetry or Point reflection is just a particular Rotation (+/-180°).
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Re: [Solved] PartDesign: Mirror along X and Y / Point Reflection / Multitranform but only keep result
Any rotation is equivalent to the product of two reflections.
In 2D, sequential reflections of any point about two lines through the origin creates a rotation of the point by twice the angle between the lines.
In 3D, sequential reflections of any point in two planes through the origin creates a rotation of the point by twice the angle between the planes about the axis defined by their intersection.
This all generalizes to n dimensions, but is much harder to visualize. This equivalence is the ultimate source of the various expressions for rotations that involve half the rotation angle, whose existence would otherwise be quite puzzling.
In 2D, sequential reflections of any point about two lines through the origin creates a rotation of the point by twice the angle between the lines.
In 3D, sequential reflections of any point in two planes through the origin creates a rotation of the point by twice the angle between the planes about the axis defined by their intersection.
This all generalizes to n dimensions, but is much harder to visualize. This equivalence is the ultimate source of the various expressions for rotations that involve half the rotation angle, whose existence would otherwise be quite puzzling.