2d translate doesn't operate in Z plane

[thesjg]

let circleA = circle({r: 5}); let circleB = circleA.translate([0,0,100]) return circleB;

Does not move the circle in the desired direction. Performing a translate in either other axis has the expected result.

[z3dev]

@thesjg thanks for the post

The operations on 2D geometry always assume Z=0, which is expected. You can convert to 3D geometry by extruding.

Will that work for your design?

[thesjg]

@z3dev I was hoping to build 3d geometry by hull()'ing or chain_hull()'ing 2d geometry together that had been translate()'d in Z. 2d geometry also doesn't appear to be able to be rotated off of Z=0. This seems to severely limit the functionality of hull, without an available 3d hull, unless I'm missing something basic?

Thanks

[thesjg]

@z3dev I solved this for my application using a rotational extrude -- just attacked it from a different direction. In keeping with the assumed Z=0 for 2D geometry, it would be nice to see the concept of "planes" or similar... and following that it would be logical to be able to project 2d geometry between planes. I think that's how the common CAD packages deal with this.

Thanks!

    let barrel = rotate_extrude({fn: 72, startAngle: 0, angle: 360},
        polygon({ points: [
            [0, 0],
            [inch_to_mm(myBarrelData['muzzle_diameter'] / 2), 0],
            [inch_to_mm(myBarrelData['neck_diameter'] / 2), inch_to_mm(myBarrelData['finish_length'] - myBarrelData['neck_length'])],
            [inch_to_mm(myBarrelData['cylinder_diameter'] / 2), inch_to_mm(myBarrelData['finish_length'] - myBarrelData['cylinder_length'])],
            [inch_to_mm(myBarrelData['cylinder_diameter'] / 2), inch_to_mm(myBarrelData['finish_length'])],
            [0, inch_to_mm(myBarrelData['finish_length'])],
            [0, 0]
        ] })
    );

[z3dev]

Super. FYI, there’s a pull request to add 3D hull to V1 of CSG #134 You might be interested in this if you get stuck in your designs.

[z3dev]

@thesjg V2 now has 3D hull, and 3D hullChain functionality. Would you like to try it out?

[z3dev]

@thesjg there’s a few changes in the ‘extrude’ space in JSCAD V2. All extrusions use the same underlying function called extrudeFromSlices(). This has been improved allowing convex as well as complex ‘slices’ to be extruded along steps. For a good example, see the code for extrudeRotate().

The key data structure is the ‘slice’ which is a planar 3D polygon. This can be transformed just like any 3D shape, and should allow further extensions to extrusions.

[thesjg]

Cool! Thanks for the updates, I will try these out!

[z3dev]

Cool. Here’s where to start.

https://openjscad.org/dokuwiki/doku.php?id=early_v2

[z3dev]

@thesjg I hope that you have a solution, or even many by now.

Please close this issue.

[thesjg]

Have not yet had a chance to try, but closing this issue to clear the clutter.

[z3dev]

Also, there are now some examples of extruding in 3D space. These might be a good starting place for you designs.

https://github.com/jscad/OpenJSCAD.org/tree/V2/packages/examples/core/curves/bezier