Expose interal utility c++ functions for computing volume, centroids, inertia, coordinate transforms; mostly used for testing.

woo.comp.cart2cyl((Vector3)xyz) → Vector3 :

Convert cartesian coordinates to cylindrical; cylindrical coordinates are specified as \((r,\theta,z)\), the reference plane is the \(xy\)-plane (see at Wikipedia).

woo.comp.computePrincipalAxes((float)V, (Vector3)Sg, (Matrix3)Ig) → tuple :

Return (pos, ori, inertia) of new coordinate system (relative to the current one), whose axes are principal, i.e. second-order momentum is diagonal (the diagonal is returned in inertia, which is sorted to be non-decreasing). The arguments are volume (mass) V, first-order momentum Sg and second-order momentum Ig. If Sg is (0,0,0), the reference point will not change, only rotation will occur.

woo.comp.cyl2cart((Vector3)rThetaZ) → Vector3 :

Convert cylindrical coordinates to cartesian; cylindrical coordinates are specified as \((r,\theta,z)\), the reference plane is the \(xy\)-plane (see at Wikipedia).

woo.comp.inertiaTensorTranslate((Matrix3)I, (float)V, (Vector3)off) → Matrix3 :

Tensor of inertia of solid translated by off with previous inertia \(I\), volume \(V\); if \(V\) is positive, the translation is away from the centroid, if negative, towards the centroid. The computation implements Parallel axes theorem.

woo.comp.tetraInertia((Vector3)A, (Vector3)B, (Vector3)C, (Vector3)D[, (bool)fixSign=True]) → Matrix3 :

Tetrahedron inertia from covariance. If fixSign is true, the tensor is multiplied by -1 if the (0,0) entry is negative (this is caued by non-canonical vertex ordering).

woo.comp.tetraInertia_grid((Vector3)A, (Vector3)B, (Vector3)C, (Vector3)D[, (int)div=100]) → Matrix3 :

Tetrahedron inertia from grid sampling (div gives subdivision along the shortest aabb side).

woo.comp.tetraVolume((Vector3)A, (Vector3)B, (Vector3)C, (Vector3)D) → float :

Volume of tetrahedron, computed as \(\frac{1}{6}((A-B)\cdot(B-D)))\times(C-D)\).

woo.comp.triangleArea((Vector3)arg1, (Vector3)arg2, (Vector3)arg3) → float
woo.comp.triangleInertia((Vector3)arg1, (Vector3)arg2, (Vector3)arg3) → Matrix3
woo.comp.uniformResamplePiecewiseLinear((object)xx, (object)yy, (Vector2)xRange, (int)div) → object :

Resample piecewise-linear function (given by points xx and yy, where xx is non-decreasing) using a uniform grid with endpoints xRange and div points (div-1 pieces), returning linearly interpolated value of yy in *div*+1 points.


Got questions? Ask at ask.woodem.org. Report issues to github.