cylindrical()

UVField MayaFlux::Kinesis::cylindrical ( const glm::vec3 &  axis = glm::vec3(0.0F, 1.0F, 0.0F), const glm::vec3 &  origin = glm::vec3(0.0F), float  radius = 1.0F, float  height = 1.0F  )

inline

Cylindrical projection around a world axis.

Parameters

axis	Cylinder axis direction (normalised by caller)
origin	Point on the cylinder axis closest to world origin
radius	Cylinder radius used to normalise the radial component
height	Full height of one UV tile along the axis

Returns

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

u = azimuth angle in [0, 1], wraps at the seam behind the axis. v = axial distance / height, unbounded — tiles vertically.

Vertices straddling the seam (angle wraps π to -π) will show a UV discontinuity. Orient geometry or rotate axis to push the seam to a non-visible region.

Definition at line 57 of file UVProjection.hpp.

{
    const glm::vec3 n = glm::normalize(axis);
 
    const glm::vec3 tangent = (std::abs(n.y) <= std::abs(n.x) && std::abs(n.y) <= std::abs(n.z))
        ? glm::normalize(glm::cross(n, glm::vec3(0.0F, 1.0F, 0.0F)))
        : glm::normalize(glm::cross(n, glm::vec3(1.0F, 0.0F, 0.0F)));
 
    const glm::vec3 bitangent = glm::cross(n, tangent);
 
    const float inv_radius = (radius > 1e-6F) ? (1.0F / radius) : 1.0F;
    const float inv_height = (height > 1e-6F) ? (1.0F / height) : 1.0F;
 
    return { .fn = [n, tangent, bitangent, origin, inv_radius, inv_height](const glm::vec3& p) -> glm::vec2 {
        const glm::vec3 d = p - origin;
        const float axial = glm::dot(d, n);
        const float radial_x = glm::dot(d, tangent) * inv_radius;
        const float radial_y = glm::dot(d, bitangent) * inv_radius;
        const float u = (glm::atan(radial_y, radial_x) / static_cast<float>(std::numbers::pi) + 1.0F) * 0.5F;
        const float v = axial * inv_height;
        return { u, v };
    } };
}