spherical()

UVField MayaFlux::Kinesis::spherical ( const glm::vec3 &  centre = glm::vec3(0.0F) )

inline

Spherical projection from a centre point.

Parameters

centre

World-space centre of the sphere

Returns

UVField: glm::vec3 -> glm::vec2

u = longitude in [0, 1], zero at +X, increasing counter-clockwise. v = latitude in [0, 1], zero at south pole, one at north pole.

Degenerate at the poles (sin(phi) -> 0) and at centre. Vertices straddling the longitude seam will show a UV discontinuity.

Definition at line 96 of file UVProjection.hpp.

{
    return { .fn = [centre](const glm::vec3& p) -> glm::vec2 {
        const glm::vec3 d = p - centre;
        const float len = glm::length(d);
        if (len < 1e-6F)
            return glm::vec2(0.0F);
 
        const glm::vec3 n = d / len;
        const float u = (glm::atan(n.z, n.x) / static_cast<float>(std::numbers::pi) + 1.0F) * 0.5F;
        const float v = n.y * 0.5F + 0.5F;
        return { u, v };
    } };
}

References MayaFlux::Kinesis::Tendency< D, R >::fn.