multi parts step files

Question

first of all i am must say that i don't know much about cad systems .

i am a software developer and i was given a task to make a webgl application that show some products in 3d .

the product is composed from multiple parts and i was given each part in a separate "STEP" file .

converting these file in other format like obj, fbx etc and showing them in 3d is not a problem but how to position / rotate each part(file) in 3d space accordingly to other parts ?

is there any option in this cad system specification that can help on that ?

thanks

Answer 1

A STEP file's orientation depends on two things:

1. How it was modeled in its originating CAD software. The designer is the one who decides how to orient the model. When exported to STEP, the model should keep the original orientation.

2. Whether said CAD software considers the Z axis as "up." While AFAIK a great majority of CAD programs do consider Z as "up", and XY as the floor, SolidWorks does not. In SolidWorks, XY is the front plane, so the Y axis is "up". That's a "feature" in their eyes. SolidWorks is the most used parametric solid modeler in the world, so many STEP files out there were made in it.

In short, they should already be oriented in the same 3D space. There is nothing more to do except perhaps rotate the parts' axes if it came from SolidWorks. Good luck!

Answer 2

Depends on how the Part was designed initially, and how they were exported. If each part does not align correctly when their origin (zero on all axis) is aligned to the global origin. Then they may have been exported individually.

Note WGLS = WebGL 3D Space

I would:

• align the parts axis to your WGLS
• set origins of parts to origin in your WGLS
• compare WGLS to an assembly view that your customer should have.

You may have assemble them in a GUI package yourself, if they don’t align. The parts then have been exported individually.