Does the MeshInspector software have a tool entry point for selecting the face to render based on the faceid?

[jiushi-ai]

Hello
Does the MeshInspector software have a tool entry point for selecting the face to render based on the faceid?

[Grantim]

Hello!

There is "Inspect/Mesh Info" tool, will it work for you?

[jiushi-ai]

thanks，

If the deviation from the common plane for two faces is greater than this value, the shared edge is marked as crease (or selected).

Could you please explain the meaning of "deviation" in this sentence?

Could you provide a demo showing these faces?

Also, what logic is used to obtain this default angle?

[Grantim]

Hello,

Hope this image clarify it:

As for default angle - it was selected as best after experimenting with different cases

[jiushi-ai]

Hello, I'm sorry, regarding this image, I still don't understand the "common planner" scenario.

Also: where is this function generally used? Hopefully, this will help me understand the function.

[Grantim]

In this case we call "common plane" - the plane containing the face. So this angle is basically angle between faces normals.

For example if two faces are is same plane - the angle is zero.

Also: where is this function generally used? Hopefully, this will help me understand the function.

Usually this is used to mark some edges as sharp for visualization purposes:
Flat shading / Smooth shading / Smooth shading with sharp creases

[jiushi-ai]

hello，

I've created a cube, and I understand the creases between each face should be 90°.

The included angle between the normals of each face should also be a right angle. I'm still confused about this.

However, the current software selects the cube's creases at 28.65°.

[Grantim]

We consider UI value as minimal angle for creases, somehow like this:

bool isCrease = angle(leftFaceNormal,rightFaceNormal) > minCreaseAngle;

So 90 > 28 that's why it is selected

[jiushi-ai]

Thank you very much, I have figured out the principle behind this crease.

Additionally: I have a new question:

Does Meshinspector have a function to add support? Or does it have a function to detect overhanging areas in the model?

Where does it detect where support needs to be added?

[Grantim]

Hello,

We have two different functions to find undercuts/overhangs:

This one finds undercuts (faces that are not accusable from given direction)

MeshLib/source/MRVoxels/MRFixUndercuts.h

Lines 88 to 98 in 23141c6

	/// Adds to \param outUndercuts undercut faces
	[[deprecated( "Use find( mesh, params)" )]]
	MRVOXELS_API MR_BIND_IGNORE void findUndercuts( const Mesh& mesh, const Vector3f& upDirection, FaceBitSet& outUndercuts );
	/// Adds to \param outUndercuts undercut vertices
	[[deprecated( "Use find( mesh, params )" )]]
	MRVOXELS_API MR_BIND_IGNORE void findUndercuts( const Mesh& mesh, const Vector3f& upDirection, VertBitSet& outUndercuts );
	/// Adds to \param outUndercuts undercut faces
	/// Returns summary metric of undercut faces
	[[deprecated( "Use find( mesh, params, metric )" )]]
	[[nodiscard]] MRVOXELS_API MR_BIND_IGNORE double findUndercuts( const Mesh& mesh, const Vector3f& upDirection, FaceBitSet& outUndercuts, const UndercutMetric& metric );

This one finds overhangs (faces that exceed given hanging distance for printing layer)

MeshLib/source/MRMesh/MRMeshOverhangs.h

Lines 26 to 30 in 23141c6

	/// \brief Find face regions that might create overhangs
	/// \param mesh - source mesh
	/// \param settings - parameters
	/// \return face regions
	MRMESH_API Expected<std::vector<FaceBitSet>> findOverhangs( const Mesh& mesh, const FindOverhangsSettings& settings );

As for supports: we don't have function to build them yet, but this video could be useful