[Feature]: Link between spline definition and geometrical definition of the part to better define a ply

[luke-ncc]

Describe the project you are working on

A simple CompoSt visualisation tool. This tool can be used to view surfaces, splines, and ply edges and cross-sections.

Describe what the format is lacking that you need in your project

Currently, plies are defined by referencing a spline. There is no surface defined for a given spline. This means plies have to be estimated, leading to inconsistency. Therefore, it is not viable to visually represent an individual ply.

State what specific feature could be added for what you need to represent

Plies could be fully defined with some geometry. Splines could be better linked to surfaces for defining the boundary.

Suggest how the feature could be implemented to support this project as well as future projects that might need this feature

Splines could be linked to surfaces, including every point in the mesh where the ply is rather than an arbitrary list of points which lie on the boundary. This would allow plies to still just be defined by these splines.

Instead of splines, plies could be defined by indexed references to all points on a mesh/surface where the ply is layered over, the corresponding triangles, and the normal for each triangle/point.

Can this feature be represented already by combining other features?

The current workflow in the software to represent a ply across a cross-section is as follows:

• User inputs a plane to render the plies for
• For each point in the spline, check if the line from that point to the next intersect the given plane
• For each intersection point, find the vector between them
• Split these lines up into a given amount of points
• Raycast from each point onto the surface
• Find the point at which the raycast hits the surface
• Create a new line through all these hit points
• Add an offset to later plies from the ply thickness The current workflow in the software to represent a ply edge is as follows:
• For each point in the spline, find the closest point on the surface
• Create a new line through all these points
• Add an offset to later plies from the ply thickness

Version

v0.67

[JKucera-NCC]

This already exists, but the problem is in clarity, documentation and flexibility.

For clarity. The CAD file stored in metadata does provide the surface geometry for all splines to relate to at defined offsets. CompoST only aims to store geometry which is only relevant for specific composite feature. Otherwise, STEP file or equivalent needs to be used.

Documentation: the above will be clarified.

The flexibility is currently limited, as STEP files with multiple surfaces or combination of surfaces and solids will make this definition problematic. In such cases, the intention is to refer to specific hash-references in STEP file. However, this is not yet fully decided and hence development of this is not priority at this early stage.