Export SVG of .STEP file not center

[joshua-alday]

Heya folks, quick disclaimer: I'm a noob to cq, but not a noob to 3D geometry operations and modelling, etc.

I'm using CQ as a part of my project to quickly render out parts for quick viewing. Our objects are created in our own cad engine and then converted to a .STEP file. I am 100% sure it's still center in both files, I've checked. However, when I use CQ to export it was an SVG, the object comes out uncentered. I would attach an example, but the upload fails for some reason.

Here is the code I use for export:

result = cq.importers.importStep("/path/to/step/part_235.step")
result.export("./outputs/part_235.svg",
	opt={                                   
		"width": 800,                           
		"height": 800,                          
		"showAxes": True,
		"showHidden": True, 
		"projectionDir": (0, 0, 1),
                "strokeColor": (0, 255, 0),
	}
)

I have tried result = result.translate() which doesn't seem to do anything to move the object.
I have also tried result = result.center() but this results in an error: OCP.Standard.Standard_ConstructionError: Bnd_Box is void

Not quite sure where to go from here, the image is off-center and documentation hasn't revealed anything to me yet.

Thank you for any info.

[lorenzncode]

There is no auto center feature when you specify both the SVG width and length. You can change marginLeft, and marginTop to try to center the shape. The shape is placed in the top left. There is a 0.75 scale factor applied.

from cadquery.func import torus

res = torus(8, 2).move(rx=45)

res.export(
    "out.svg",
    opt={
        "width": 800,
        "height": 800,
        "marginLeft": 0,
        "marginTop": 0,
        "projectionDir": (0, 0, 1),
        "strokeColor": (0, 255, 0),
    },
)

If you set one of width or height to None, it will automatically center the shape.

Here the shape is centered and the SVG height is set automatically to fit the shape.
The size ends up to be 800x613.

from cadquery.func import torus

res = torus(8, 2).move(rx=45)

res.export(
    "out.svg",
    opt={
        "width": 800,
        "height": None,
        "marginLeft": 0,
        "marginTop": 0,
        "projectionDir": (0, 0, 1),
        "strokeColor": (0, 255, 0),
    },
)

[joshua-alday]

@lorenzncode Thank you for the information. I'll put these suggestions to use.