tiny.rig.Transform

1/// A rigid transform. Rig normalizes every rotation before it composes or2/// applies one, so rotations read from specs and ABIs need not be unit length.3pub const Transform = struct {4    translation: Vec3 = .{},5    rotation: Quat = .{},67    pub fn identity() Transform {8        return .{};9    }1011    pub fn compose(parent: Transform, child: Transform) Transform {12        return .{13            .translation = parent.translation.add(rotate(parent.rotation, child.translation)),14            .rotation = unit(unit(parent.rotation).mul(unit(child.rotation))),15        };16    }1718    pub fn applyPoint(self: Transform, point: Vec3) Vec3 {19        return self.translation.add(rotate(self.rotation, point));20    }2122    pub fn inversePoint(self: Transform, point: Vec3) Vec3 {23        return rotate(unit(self.rotation).conjugate(), point.sub(self.translation));24    }2526    /// The transform that undoes this one: `compose(t.inverse(), t)` is the27    /// identity up to rounding.28    pub fn inverse(self: Transform) Transform {29        const rotation = unit(self.rotation).conjugate();30        return .{31            .translation = rotation.rotate(self.translation).scale(-1),32            .rotation = rotation,33        };34    }35};

1pub const Transform = transform.Transform;