topic Re: Struggling to get script-generated sketch to line up with existing sketch in design in Fusion API and Scripts Forum

Struggling to get script-generated sketch to line up with existing sketch in design

darrenPH8TL — Thu, 21 Dec 2023 18:46:07 GMT

I'm trying to create my first script. I've made it as far as creating a sketch with two nested, constrained rectangles in it. Now I want that sketch to line up with an existing sketch.

I can get it on the same plane, but the coordinate system is rotated vs what I expect. The bottom sketch's geometry is supposed to be in the positive XY quadrant, but as you can see it gets inserted rotated. This is a clean test design with a sketch with one rectangle on it.

How can I copy the existing sketch's origin, size and coordinate system? Ideally I want to pick any existing sketch and place my generated sketch and its geometry on the same plane, or on an offset plane directly "above" the existing plane and sized exactly the same. It's my intent to generate patterned geometry to intersect and cut the existing geometry.

# Create a new sketch. thisComp = design.rootComponent sketches = thisComp.sketches masterSketch = sketches.item(0) # Get the profile prof = masterSketch.profiles.item(0) # Get construction planes planes = thisComp.constructionPlanes # Create construction plane input planeInput = planes.createInput() # Add construction plane by offset offsetValue = adsk.core.ValueInput.createByReal(0) planeInput.setByOffset(prof, offsetValue) planeOne = planes.add(planeInput) sketch = sketches.add(planeOne)

Re: Struggling to get script-generated sketch to line up with existing sketch in design

BrianEkins — Thu, 21 Dec 2023 22:10:55 GMT

I'm not following exactly what you're trying to do, but hopefully, this will help.

Each sketch has its coordinate system, and all the geometry created within it is relative to that coordinate system. Fusion doesn't give you any control over the position or orientation of a sketch. Sketches are created by selecting a construction plane or planar face. Fusion has some internal algorithm to create the sketch and keep it associatively linked to the selected construction plane or face.

There are some functions on the Sketch object that let you get information about the sketch space and go between sketch and model space. These are modelToSketchSpace, sketchToModelSpace, transform, xDirection, and yDirection.

Re: Struggling to get script-generated sketch to line up with existing sketch in design

darrenPH8TL — Thu, 21 Dec 2023 22:25:22 GMT

What I am trying to do is pretty simple. I want to programmatically generate some geometry and place it in its own sketch that is aligned with an existing sketch. Then I want to use that geometry as a cutting tool.

Specifically, I am creating my own custom patterns to cut the vertical sides of 3D printed objects. The patterns are self-supporting so that no support material is needed. The purpose is for creating lighter parts that require less filament to make, and thus cost less to produce and print faster.

I can achieve the result manually by drawing in Fusion and then repeating as a pattern, but it is very tedious. Doing it in a script will save me countless hours and allow me to quickly iterate through different options.

Re: Struggling to get script-generated sketch to line up with existing sketch in design

kandennti — Fri, 22 Dec 2023 15:20:40 GMT

Hi @darrenPH8TL -San.

Is this what it's like?

# Fusion360API Python script import traceback import adsk.core as core import adsk.fusion as fusion def run(context): ui: core.UserInterface = None try: app: core.Application = core.Application.get() ui = app.userInterface msg: str = 'Select Sketch' selFilter: str = "Sketches,SketchCurves,SketchPoints" sel: core.Selection = select_ent(msg, selFilter) if not sel: return create_clone_sketch(sel.entity) ui.messageBox('Done') except: if ui: ui.messageBox('Failed:\n{}'.format(traceback.format_exc())) def create_clone_sketch( sktEntity: fusion.SketchEntity ) -> fusion.Sketch: skt: fusion.Sketch = None if sktEntity.classType() == fusion.Sketch.classType(): skt = sktEntity else: skt = sktEntity.parentSketch comp: fusion.Component = skt.parentComponent refPlane = skt.referencePlane # get sketch entities sktEnts: core.ObjectCollection = core.ObjectCollection.createWithArray( list(skt.sketchCurves), ) [sktEnts.add(pnt) for pnt in skt.sketchPoints] # create offset plane planes: fusion.ConstructionPlanes = comp.constructionPlanes planeIpt: fusion.ConstructionPlaneInput = planes.createInput() planeIpt.setByOffset( refPlane, core.ValueInput.createByReal(0), ) offsetPlane: fusion.ConstructionPlane = planes.add(planeIpt) # create sketch cloneSkt: fusion.Sketch = comp.sketches.add(offsetPlane) # copy cloneSkt.copy( sktEnts, core.Matrix3D.create(), ) return cloneSkt def select_ent( msg: str, filterStr: str ) -> core.Selection: try: app: core.Application = core.Application.get() ui: core.UserInterface = app.userInterface sel = ui.selectEntity(msg, filterStr) return sel except: return None

Re: Struggling to get script-generated sketch to line up with existing sketch in design

darrenPH8TL — Fri, 22 Dec 2023 19:50:02 GMT

That's getting there. As soon as I call design.rootComponent.sketches.add(clonedSketch), the add call throws an exception: "3 : not a planar entity".

But what's really odd is that even with the exception, the cloned sketch is indeed added to the design and matches the position and dimension of the original.

Re: Struggling to get script-generated sketch to line up with existing sketch in design

kandennti — Sat, 23 Dec 2023 13:41:59 GMT

@darrenPH8TL -San.

We have not been able to reproduce such a condition.
It may be an inherent problem with the data you are trying.

Re: Struggling to get script-generated sketch to line up with existing sketch in design

darrenPH8TL — Sat, 23 Dec 2023 18:44:54 GMT

I can make up a package to send to you with the script and the design. The sample design file is a single sketch with a single rectangle in it. Where would I upload that?

Re: Struggling to get script-generated sketch to line up with existing sketch in design

darrenPH8TL — Sun, 24 Dec 2023 22:21:36 GMT

After some more investigation, the clone_sketch function provided is already inserting the cloned sketch into the design,which I didn't realize until I read the code. So my code was trying to insert it a second time. I took out my code to add it a second time and now it's good. No idea why that throws a "non planar entity" exception. :shrug:

Now I just need to access some parameters from the design file so I can use them in my script. They appear to be in Design->allParameters.