godot-cpp/src/core/Transform.cpp

#include "Transform.hpp"

#include "Basis.hpp"

#include "Plane.hpp"
#include "AABB.hpp"

#include "Quat.hpp"

namespace godot {



Transform Transform::inverse_xform(const Transform& t) const {

	Vector3 v = t.origin - origin;
	return Transform(basis.transpose_xform(t.basis),
		basis.xform(v));
}

void Transform::set(real_t xx, real_t xy, real_t xz, real_t yx, real_t yy, real_t yz, real_t zx, real_t zy, real_t zz,real_t tx, real_t ty, real_t tz) {

	basis.elements[0][0]=xx;
	basis.elements[0][1]=xy;
	basis.elements[0][2]=xz;
	basis.elements[1][0]=yx;
	basis.elements[1][1]=yy;
	basis.elements[1][2]=yz;
	basis.elements[2][0]=zx;
	basis.elements[2][1]=zy;
	basis.elements[2][2]=zz;
	origin.x=tx;
	origin.y=ty;
	origin.z=tz;
}



Vector3 Transform::xform(const Vector3& p_vector) const {

	return Vector3(
		basis[0].dot(p_vector)+origin.x,
		basis[1].dot(p_vector)+origin.y,
		basis[2].dot(p_vector)+origin.z
	);
}
Vector3 Transform::xform_inv(const Vector3& p_vector) const {

	Vector3 v = p_vector - origin;

	return Vector3(
		(basis.elements[0][0]*v.x ) + ( basis.elements[1][0]*v.y ) + ( basis.elements[2][0]*v.z ),
		(basis.elements[0][1]*v.x ) + ( basis.elements[1][1]*v.y ) + ( basis.elements[2][1]*v.z ),
		(basis.elements[0][2]*v.x ) + ( basis.elements[1][2]*v.y ) + ( basis.elements[2][2]*v.z )
	);
}

Plane Transform::xform(const Plane& p_plane) const {


	Vector3 point=p_plane.normal*p_plane.d;
	Vector3 point_dir=point+p_plane.normal;
	point=xform(point);
	point_dir=xform(point_dir);

	Vector3 normal=point_dir-point;
	normal.normalize();
	real_t d=normal.dot(point);

	return Plane(normal,d);

}
Plane Transform::xform_inv(const Plane& p_plane) const {

	Vector3 point=p_plane.normal*p_plane.d;
	Vector3 point_dir=point+p_plane.normal;
	xform_inv(point);
	xform_inv(point_dir);

	Vector3 normal=point_dir-point;
	normal.normalize();
	real_t d=normal.dot(point);

	return Plane(normal,d);

}

AABB Transform::xform(const AABB& p_aabb) const {
	/* define vertices */
	Vector3 x=basis.get_axis(0)*p_aabb.size.x;
	Vector3 y=basis.get_axis(1)*p_aabb.size.y;
	Vector3 z=basis.get_axis(2)*p_aabb.size.z;
	Vector3 pos = xform( p_aabb.position );
//could be even further optimized
	AABB new_aabb;
	new_aabb.position=pos;
	new_aabb.expand_to( pos+x );
	new_aabb.expand_to( pos+y );
	new_aabb.expand_to( pos+z );
	new_aabb.expand_to( pos+x+y );
	new_aabb.expand_to( pos+x+z );
	new_aabb.expand_to( pos+y+z );
	new_aabb.expand_to( pos+x+y+z );
	return new_aabb;

}
AABB Transform::xform_inv(const AABB& p_aabb) const {

	/* define vertices */
	Vector3 vertices[8]={
			Vector3(p_aabb.position.x+p_aabb.size.x,	p_aabb.position.y+p_aabb.size.y,	p_aabb.position.z+p_aabb.size.z),
			Vector3(p_aabb.position.x+p_aabb.size.x,	p_aabb.position.y+p_aabb.size.y,	p_aabb.position.z),
			Vector3(p_aabb.position.x+p_aabb.size.x,	p_aabb.position.y,		p_aabb.position.z+p_aabb.size.z),
			Vector3(p_aabb.position.x+p_aabb.size.x,	p_aabb.position.y,		p_aabb.position.z),
			Vector3(p_aabb.position.x,	p_aabb.position.y+p_aabb.size.y,	p_aabb.position.z+p_aabb.size.z),
			Vector3(p_aabb.position.x,	p_aabb.position.y+p_aabb.size.y,	p_aabb.position.z),
			Vector3(p_aabb.position.x,	p_aabb.position.y,		p_aabb.position.z+p_aabb.size.z),
			Vector3(p_aabb.position.x,	p_aabb.position.y,		p_aabb.position.z)
	};


	AABB ret;

	ret.position=xform_inv(vertices[0]);

	for (int i=1;i<8;i++) {

		ret.expand_to( xform_inv(vertices[i]) );
	}

	return ret;

}

void Transform::affine_invert() {

	basis.invert();
	origin = basis.xform(-origin);
}

Transform Transform::affine_inverse() const {

	Transform ret=*this;
	ret.affine_invert();
	return ret;

}


void Transform::invert() {

	basis.transpose();
	origin = basis.xform(-origin);
}

Transform Transform::inverse() const {
	// FIXME: this function assumes the basis is a rotation matrix, with no scaling.
	// Transform::affine_inverse can handle matrices with scaling, so GDScript should eventually use that.
	Transform ret=*this;
	ret.invert();
	return ret;
}


void Transform::rotate(const Vector3& p_axis,real_t p_phi) {

	*this = rotated(p_axis, p_phi);
}

Transform Transform::rotated(const Vector3& p_axis,real_t p_phi) const{

	return Transform(Basis( p_axis, p_phi ), Vector3()) * (*this);
}

void Transform::rotate_basis(const Vector3& p_axis,real_t p_phi) {

	basis.rotate(p_axis,p_phi);
}

Transform Transform::looking_at( const Vector3& p_target, const Vector3& p_up ) const {

	Transform t = *this;
	t.set_look_at(origin,p_target,p_up);
	return t;
}

void Transform::set_look_at( const Vector3& p_eye, const Vector3& p_target, const Vector3& p_up ) {

	// Reference: MESA source code
	Vector3 v_x, v_y, v_z;

	/* Make rotation matrix */

	/* Z vector */
	v_z = p_eye - p_target;

	v_z.normalize();

	v_y = p_up;


	v_x=v_y.cross(v_z);

	/* Recompute Y = Z cross X */
	v_y=v_z.cross(v_x);

	v_x.normalize();
	v_y.normalize();

	basis.set_axis(0,v_x);
	basis.set_axis(1,v_y);
	basis.set_axis(2,v_z);
	origin=p_eye;

}

Transform Transform::interpolate_with(const Transform& p_transform, real_t p_c) const {

	/* not sure if very "efficient" but good enough? */

	Vector3 src_scale = basis.get_scale();
	Quat src_rot = basis;
	Vector3 src_loc = origin;

	Vector3 dst_scale = p_transform.basis.get_scale();
	Quat dst_rot = p_transform.basis;
	Vector3 dst_loc = p_transform.origin;

	Transform dst;
	dst.basis=src_rot.slerp(dst_rot,p_c);
	dst.basis.scale(src_scale.linear_interpolate(dst_scale,p_c));
	dst.origin=src_loc.linear_interpolate(dst_loc,p_c);

	return dst;
}

void Transform::scale(const Vector3& p_scale) {

	basis.scale(p_scale);
	origin*=p_scale;
}

Transform Transform::scaled(const Vector3& p_scale) const {

	Transform t = *this;
	t.scale(p_scale);
	return t;
}

void Transform::scale_basis(const Vector3& p_scale) {

	basis.scale(p_scale);
}

void Transform::translate( real_t p_tx, real_t p_ty, real_t p_tz)  {
	translate( Vector3(p_tx,p_ty,p_tz) );

}
void Transform::translate( const Vector3& p_translation ) {

	for( int i = 0; i < 3; i++ ) {
		origin[i] += basis[i].dot(p_translation);
	}
}

Transform Transform::translated( const Vector3& p_translation ) const {

	Transform t=*this;
	t.translate(p_translation);
	return t;
}

void Transform::orthonormalize() {

	basis.orthonormalize();
}

Transform Transform::orthonormalized() const {

	Transform _copy = *this;
	_copy.orthonormalize();
	return _copy;
}

bool Transform::operator==(const Transform& p_transform) const {

	return (basis==p_transform.basis && origin==p_transform.origin);
}
bool Transform::operator!=(const Transform& p_transform) const {

	return (basis!=p_transform.basis || origin!=p_transform.origin);
}

void Transform::operator*=(const Transform& p_transform) {

	origin=xform(p_transform.origin);
	basis*=p_transform.basis;
}

Transform Transform::operator*(const Transform& p_transform) const {

	Transform t=*this;
	t*=p_transform;
	return t;
}

Transform::operator String() const {

	return basis.operator String() + " - " + origin.operator String();
}


Transform::Transform(const Basis& p_basis, const Vector3& p_origin) {

	basis=p_basis;
	origin=p_origin;
}

}