Function mat4_from_trs

native/shared/src/models.rs:615–629

(t: &[f32; 3], r: &[f32; 4], s: &[f32; 3])

}

fn mat4_from_trs(t: &[f32; 3], r: &[f32; 4], s: &[f32; 3]) -> [[f32; 4]; 4] {
    let (x, y, z, w) = (r[0], r[1], r[2], r[3]);
    let x2 = x + x; let y2 = y + y; let z2 = z + z;
    let xx = x * x2; let xy = x * y2; let xz = x * z2;
    let yy = y * y2; let yz = y * z2; let zz = z * z2;
    let wx = w * x2; let wy = w * y2; let wz = w * z2;

    // Column-major: m[col][row]
    [
        [(1.0 - (yy + zz)) * s[0], (xy + wz) * s[0],         (xz - wy) * s[0],         0.0],  // column 0
        [(xy - wz) * s[1],         (1.0 - (xx + zz)) * s[1], (yz + wx) * s[1],         0.0],  // column 1
        [(xz + wy) * s[2],         (yz - wx) * s[2],         (1.0 - (xx + yy)) * s[2], 0.0],  // column 2
        [t[0],                      t[1],                      t[2],                      1.0],  // column 3 (translation)
    ]
}

fn quat_slerp(a: &[f32; 4], b: &[f32; 4], t: f32) -> [f32; 4] {
    let mut dot = a[0]*b[0] + a[1]*b[1] + a[2]*b[2] + a[3]*b[3];