Auto Convert STEP to STEP 242 and store Shape Representation

[Mannshoch]

For a seamless open and preview of geometric data, a rendered body would be helpful. Depending on the size of a body, such a rendering need time. Since STEP 242 it is supported to store a tessellated_shape_representation along with the body.

I propose add a tick:

• "auto convert STEP to version 242 and store 3D preview graphic for faster preview"
  • convert only if file is stored in Directory: [...]

With this tick every time a STEP older than 242 is opened, a tessellated_shape_representation is calculated and inserted after the STEP file is converted and enhanced to a STEP 242.

[Mannshoch]

I did an experiment and opened a 600MB STEP and exportet the top tree item into step again. The filesize grows to 1.58 GB and the opening time encreased.