gecko-dev/gfx/2d/Quaternion.h

103 строки
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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef MOZILLA_GFX_QUATERNION_H_
#define MOZILLA_GFX_QUATERNION_H_
#include "Types.h"
#include <math.h>
#include <ostream>
#include "mozilla/Attributes.h"
#include "mozilla/DebugOnly.h"
#include "mozilla/gfx/MatrixFwd.h"
#include "mozilla/gfx/Point.h"
namespace mozilla {
namespace gfx {
class Quaternion {
public:
Quaternion() : x(0.0f), y(0.0f), z(0.0f), w(1.0f) {}
Quaternion(Float aX, Float aY, Float aZ, Float aW)
: x(aX), y(aY), z(aZ), w(aW) {}
Quaternion(const Quaternion& aOther) { memcpy(this, &aOther, sizeof(*this)); }
Float x, y, z, w;
friend std::ostream& operator<<(std::ostream& aStream,
const Quaternion& aQuat);
void Set(Float aX, Float aY, Float aZ, Float aW) {
x = aX;
y = aY;
z = aZ;
w = aW;
}
// Assumes upper 3x3 of aMatrix is a pure rotation matrix (no scaling)
void SetFromRotationMatrix(const Matrix4x4& aMatrix);
// result = this * aQuat
Quaternion operator*(const Quaternion& aQuat) const {
Quaternion o;
const Float bx = aQuat.x, by = aQuat.y, bz = aQuat.z, bw = aQuat.w;
o.x = x * bw + w * bx + y * bz - z * by;
o.y = y * bw + w * by + z * bx - x * bz;
o.z = z * bw + w * bz + x * by - y * bx;
o.w = w * bw - x * bx - y * by - z * bz;
return o;
}
Quaternion& operator*=(const Quaternion& aQuat) {
*this = *this * aQuat;
return *this;
}
Float Length() const { return sqrt(x * x + y * y + z * z + w * w); }
Quaternion& Conjugate() {
x *= -1.f;
y *= -1.f;
z *= -1.f;
return *this;
}
Quaternion& Normalize() {
Float l = Length();
if (l) {
l = 1.0f / l;
x *= l;
y *= l;
z *= l;
w *= l;
} else {
x = y = z = 0.f;
w = 1.f;
}
return *this;
}
Quaternion& Invert() { return Conjugate().Normalize(); }
Point3D RotatePoint(const Point3D& aPoint) {
Float uvx = Float(2.0) * (y * aPoint.z - z * aPoint.y);
Float uvy = Float(2.0) * (z * aPoint.x - x * aPoint.z);
Float uvz = Float(2.0) * (x * aPoint.y - y * aPoint.x);
return Point3D(aPoint.x + w * uvx + y * uvz - z * uvy,
aPoint.y + w * uvy + z * uvx - x * uvz,
aPoint.z + w * uvz + x * uvy - y * uvx);
}
};
} // namespace gfx
} // namespace mozilla
#endif