Creates a new Annulus geometry.
Configuration options.
Protected_Cached bounding volume to prevent re-allocation
Protected_The indices of the geometry for indexed rendering.
Protected_Whether the geometry is purely line-based.
Protected Optional_Optional skinning joints (4 IDs per vertex).
Protected_The normals of the geometry (nx, ny, nz).
Protected_The tangents of the geometry (tx, ty, tz).
Protected_The UV coordinates of the geometry (u, v).
Protected_The vertices of the geometry (x, y, z).
Protected Optional_Optional skinning weights (4 weights per vertex).
Protected_The indices for wireframe rendering.
Inner radius (r).
Outer radius (R).
Number of concentric subdivisions across ring width.
Central angle in radians.
Number of radial subdivisions around circumference.
Start angle in radians.
Protected_Helper method to create an appropriately sized index array. Automatically chooses between 16-bit and 32-bit indices based on vertex count.
The number of indices needed.
A Uint16Array or Uint32Array.
Applies a Matrix4 transformation to all geometry vertices in-place.
The transformation matrix.
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Computes the normals of the geometry using the current vertices and indices. Averages normals for shared vertices.
Computes the tangents of the geometry based on normals and UVs. Required for normal mapping.
Computes the wireframe indices (line-segments) from the current triangle topology.
ProtectedgenerateGenerates the raw geometry data. Must be implemented by subclasses.
Calculates the surface area $A = \frac{\theta_{\text{len}}}{2\pi} \cdot \pi (R^2 - r^2)$.
Returns a bounding volume that encapsulates this geometry.
The bounding volume.
Returns the raw geometry data ready for GPU upload.
The geometry data interface.
Calculates the median radius $r_{\text{med}} = \frac{R + r}{2}$.
Calculates the total perimeter $U = \frac{\theta_{\text{len}}}{2\pi} \cdot 2\pi (R + r)$ (plus side radial edges if sector).
Calculates the tangent chord length $l = 2\sqrt{R^2 - r^2}$.
Calculates the ring width / wall thickness $b = R - r$.
Rotates the geometry vertices around the X-axis in-place.
The rotation angle in radians.
this
Rotates the geometry vertices around the Y-axis in-place.
The rotation angle in radians.
this
Rotates the geometry vertices around the Z-axis in-place.
The rotation angle in radians.
this
Scales the geometry vertices in-place.
The scale factor.
this
A planar annulus geometry (Kreisring / 2D flat circular ring).
A flat 2D ring lying in the X-Z plane with normal $(0, 1, 0)$, bounded by an inner radius $r$ and an outer radius $R$.
Mathematical formulas:
See
https://rechneronline.de/pi/kreisring.php