virtualx-engine/core/math/transform.h
Rémi Verschelde 1426cd3b3a
One Copyright Update to rule them all
As many open source projects have started doing it, we're removing the
current year from the copyright notice, so that we don't need to bump
it every year.

It seems like only the first year of publication is technically
relevant for copyright notices, and even that seems to be something
that many companies stopped listing altogether (in a version controlled
codebase, the commits are a much better source of date of publication
than a hardcoded copyright statement).

We also now list Godot Engine contributors first as we're collectively
the current maintainers of the project, and we clarify that the
"exclusive" copyright of the co-founders covers the timespan before
opensourcing (their further contributions are included as part of Godot
Engine contributors).

Also fixed "cf." Frenchism - it's meant as "refer to / see".

Backported from #70885.
2023-01-10 15:26:54 +01:00

263 lines
10 KiB
C++

/**************************************************************************/
/* transform.h */
/**************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* https://godotengine.org */
/**************************************************************************/
/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur. */
/* */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the */
/* "Software"), to deal in the Software without restriction, including */
/* without limitation the rights to use, copy, modify, merge, publish, */
/* distribute, sublicense, and/or sell copies of the Software, and to */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions: */
/* */
/* The above copyright notice and this permission notice shall be */
/* included in all copies or substantial portions of the Software. */
/* */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. */
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
/**************************************************************************/
#ifndef TRANSFORM_H
#define TRANSFORM_H
#include "core/math/aabb.h"
#include "core/math/basis.h"
#include "core/math/plane.h"
#include "core/pool_vector.h"
class _NO_DISCARD_CLASS_ Transform {
public:
Basis basis;
Vector3 origin;
void invert();
Transform inverse() const;
void affine_invert();
Transform affine_inverse() const;
Transform rotated(const Vector3 &p_axis, real_t p_angle) const;
void rotate(const Vector3 &p_axis, real_t p_angle);
void rotate_basis(const Vector3 &p_axis, real_t p_angle);
void set_look_at(const Vector3 &p_eye, const Vector3 &p_target, const Vector3 &p_up);
Transform looking_at(const Vector3 &p_target, const Vector3 &p_up) const;
void scale(const Vector3 &p_scale);
Transform scaled(const Vector3 &p_scale) const;
void scale_basis(const Vector3 &p_scale);
void translate(real_t p_tx, real_t p_ty, real_t p_tz);
void translate(const Vector3 &p_translation);
Transform translated(const Vector3 &p_translation) const;
const Basis &get_basis() const { return basis; }
void set_basis(const Basis &p_basis) { basis = p_basis; }
const Vector3 &get_origin() const { return origin; }
void set_origin(const Vector3 &p_origin) { origin = p_origin; }
void orthonormalize();
Transform orthonormalized() const;
bool is_equal_approx(const Transform &p_transform) const;
bool operator==(const Transform &p_transform) const;
bool operator!=(const Transform &p_transform) const;
_FORCE_INLINE_ Vector3 xform(const Vector3 &p_vector) const;
_FORCE_INLINE_ AABB xform(const AABB &p_aabb) const;
_FORCE_INLINE_ PoolVector<Vector3> xform(const PoolVector<Vector3> &p_array) const;
// NOTE: These are UNSAFE with non-uniform scaling, and will produce incorrect results.
// They use the transpose.
// For safe inverse transforms, xform by the affine_inverse.
_FORCE_INLINE_ Vector3 xform_inv(const Vector3 &p_vector) const;
_FORCE_INLINE_ AABB xform_inv(const AABB &p_aabb) const;
_FORCE_INLINE_ PoolVector<Vector3> xform_inv(const PoolVector<Vector3> &p_array) const;
// Safe with non-uniform scaling (uses affine_inverse).
_FORCE_INLINE_ Plane xform(const Plane &p_plane) const;
_FORCE_INLINE_ Plane xform_inv(const Plane &p_plane) const;
// These fast versions use precomputed affine inverse, and should be used in bottleneck areas where
// multiple planes are to be transformed.
_FORCE_INLINE_ Plane xform_fast(const Plane &p_plane, const Basis &p_basis_inverse_transpose) const;
static _FORCE_INLINE_ Plane xform_inv_fast(const Plane &p_plane, const Transform &p_inverse, const Basis &p_basis_transpose);
void operator*=(const Transform &p_transform);
Transform operator*(const Transform &p_transform) const;
Transform interpolate_with(const Transform &p_transform, real_t p_c) const;
_FORCE_INLINE_ Transform inverse_xform(const Transform &t) const {
Vector3 v = t.origin - origin;
return Transform(basis.transpose_xform(t.basis),
basis.xform(v));
}
void 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.set(xx, xy, xz, yx, yy, yz, zx, zy, zz);
origin.x = tx;
origin.y = ty;
origin.z = tz;
}
operator String() const;
Transform(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 ox, real_t oy, real_t oz);
Transform(const Basis &p_basis, const Vector3 &p_origin = Vector3());
Transform() {}
};
_FORCE_INLINE_ 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);
}
_FORCE_INLINE_ 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));
}
// Neither the plane regular xform or xform_inv are particularly efficient,
// as they do a basis inverse. For xforming a large number
// of planes it is better to pre-calculate the inverse transpose basis once
// and reuse it for each plane, by using the 'fast' version of the functions.
_FORCE_INLINE_ Plane Transform::xform(const Plane &p_plane) const {
Basis b = basis.inverse();
b.transpose();
return xform_fast(p_plane, b);
}
_FORCE_INLINE_ Plane Transform::xform_inv(const Plane &p_plane) const {
Transform inv = affine_inverse();
Basis basis_transpose = basis.transposed();
return xform_inv_fast(p_plane, inv, basis_transpose);
}
_FORCE_INLINE_ AABB Transform::xform(const AABB &p_aabb) const {
/* http://dev.theomader.com/transform-bounding-boxes/ */
Vector3 min = p_aabb.position;
Vector3 max = p_aabb.position + p_aabb.size;
Vector3 tmin, tmax;
for (int i = 0; i < 3; i++) {
tmin[i] = tmax[i] = origin[i];
for (int j = 0; j < 3; j++) {
real_t e = basis[i][j] * min[j];
real_t f = basis[i][j] * max[j];
if (e < f) {
tmin[i] += e;
tmax[i] += f;
} else {
tmin[i] += f;
tmax[i] += e;
}
}
}
AABB r_aabb;
r_aabb.position = tmin;
r_aabb.size = tmax - tmin;
return r_aabb;
}
_FORCE_INLINE_ 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;
}
PoolVector<Vector3> Transform::xform(const PoolVector<Vector3> &p_array) const {
PoolVector<Vector3> array;
array.resize(p_array.size());
PoolVector<Vector3>::Read r = p_array.read();
PoolVector<Vector3>::Write w = array.write();
for (int i = 0; i < p_array.size(); ++i) {
w[i] = xform(r[i]);
}
return array;
}
PoolVector<Vector3> Transform::xform_inv(const PoolVector<Vector3> &p_array) const {
PoolVector<Vector3> array;
array.resize(p_array.size());
PoolVector<Vector3>::Read r = p_array.read();
PoolVector<Vector3>::Write w = array.write();
for (int i = 0; i < p_array.size(); ++i) {
w[i] = xform_inv(r[i]);
}
return array;
}
_FORCE_INLINE_ Plane Transform::xform_fast(const Plane &p_plane, const Basis &p_basis_inverse_transpose) const {
// Transform a single point on the plane.
Vector3 point = p_plane.normal * p_plane.d;
point = xform(point);
// Use inverse transpose for correct normals with non-uniform scaling.
Vector3 normal = p_basis_inverse_transpose.xform(p_plane.normal);
normal.normalize();
real_t d = normal.dot(point);
return Plane(normal, d);
}
_FORCE_INLINE_ Plane Transform::xform_inv_fast(const Plane &p_plane, const Transform &p_inverse, const Basis &p_basis_transpose) {
// Transform a single point on the plane.
Vector3 point = p_plane.normal * p_plane.d;
point = p_inverse.xform(point);
// Note that instead of precalculating the transpose, an alternative
// would be to use the transpose for the basis transform.
// However that would be less SIMD friendly (requiring a swizzle).
// So the cost is one extra precalced value in the calling code.
// This is probably worth it, as this could be used in bottleneck areas. And
// where it is not a bottleneck, the non-fast method is fine.
// Use transpose for correct normals with non-uniform scaling.
Vector3 normal = p_basis_transpose.xform(p_plane.normal);
normal.normalize();
real_t d = normal.dot(point);
return Plane(normal, d);
}
#endif // TRANSFORM_H