gecko-dev/gfx/thebes/gfx3DMatrix.h

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/* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 4 -*-
* 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 GFX_3DMATRIX_H
#define GFX_3DMATRIX_H
#include <gfxTypes.h>
#include "mozilla/gfx/Point.h"
#include <gfxQuad.h>
class gfxMatrix;
/**
* This class represents a 3D transformation. The matrix is laid
* out as follows:
*
* _11 _12 _13 _14
* _21 _22 _23 _24
* _31 _32 _33 _34
* _41 _42 _43 _44
*
* This matrix is treated as row-major. Assuming we consider our vectors row
* vectors, this matrix type will be identical in memory to the OpenGL and D3D
* matrices. OpenGL matrices are column-major, however OpenGL also treats
* vectors as column vectors, the double transposition makes everything work
* out nicely.
*/
class gfx3DMatrix
{
typedef mozilla::gfx::Point3D Point3D;
typedef mozilla::gfx::Point4D Point4D;
public:
/**
* Create matrix.
*/
gfx3DMatrix(void);
friend std::ostream& operator<<(std::ostream& stream, const gfx3DMatrix& m) {
if (m.IsIdentity()) {
return stream << "[ I ]";
}
if (m.Is2D()) {
return stream << "["
<< m._11 << " " << m._12 << "; "
<< m._21 << " " << m._22 << "; "
<< m._41 << " " << m._42
<< "]";
}
return stream << "["
<< m._11 << " " << m._12 << " " << m._13 << " " << m._14 << "; "
<< m._21 << " " << m._22 << " " << m._23 << " " << m._24 << "; "
<< m._31 << " " << m._32 << " " << m._33 << " " << m._34 << "; "
<< m._41 << " " << m._42 << " " << m._43 << " " << m._44
<< "]";
}
/**
* Matrix multiplication.
*/
gfx3DMatrix operator*(const gfx3DMatrix &aMatrix) const;
gfx3DMatrix& operator*=(const gfx3DMatrix &aMatrix);
Point4D& operator[](int aIndex)
{
MOZ_ASSERT(aIndex >= 0 && aIndex <= 3, "Invalid matrix array index");
return *reinterpret_cast<Point4D*>((&_11)+4*aIndex);
}
const Point4D& operator[](int aIndex) const
{
MOZ_ASSERT(aIndex >= 0 && aIndex <= 3, "Invalid matrix array index");
return *reinterpret_cast<const Point4D*>((&_11)+4*aIndex);
}
/**
* Return true if this matrix and |aMatrix| are the same matrix.
*/
bool operator==(const gfx3DMatrix& aMatrix) const;
bool operator!=(const gfx3DMatrix& aMatrix) const;
bool FuzzyEqual(const gfx3DMatrix& aMatrix) const;
/**
* Divide all values in the matrix by a scalar value
*/
gfx3DMatrix& operator/=(gfxFloat scalar);
/**
* Create a 3D matrix from a gfxMatrix 2D affine transformation.
*
* \param aMatrix gfxMatrix 2D affine transformation.
*/
static gfx3DMatrix From2D(const gfxMatrix &aMatrix);
/**
* Returns true if the matrix is isomorphic to a 2D affine transformation
* (i.e. as obtained by From2D). If it is, optionally returns the 2D
* matrix in aMatrix.
*/
bool Is2D(gfxMatrix* aMatrix) const;
bool Is2D() const;
/**
* Returns true if the matrix can be reduced to a 2D affine transformation
* (i.e. as obtained by From2D). If it is, optionally returns the 2D
* matrix in aMatrix. This should only be used on matrices required for
* rendering, not for intermediate calculations. It is assumed that the 2D
* matrix will only be used for transforming objects on to the z=0 plane,
* therefore any z-component perspective is ignored. This means that if
* aMatrix is applied to objects with z != 0, the results may be incorrect.
*
* Since drawing is to a 2d plane, any 3d transform without perspective
* can be reduced by dropping the z row and column.
*/
bool CanDraw2D(gfxMatrix* aMatrix = nullptr) const;
/**
* Converts the matrix to one that doesn't modify the z coordinate of points,
* but leaves the rest of the transformation unchanged.
*/
gfx3DMatrix& ProjectTo2D();
/**
* Returns true if the matrix is the identity matrix. The most important
* property we require is that gfx3DMatrix().IsIdentity() returns true.
*/
bool IsIdentity() const;
/**
* Pre-multiplication transformation functions:
*
* These functions construct a temporary matrix containing
* a single transformation and pre-multiply it onto the current
* matrix.
*/
/**
* Add a translation by aPoint to the matrix.
*
* This creates this temporary matrix:
* | 1 0 0 0 |
* | 0 1 0 0 |
* | 0 0 1 0 |
* | aPoint.x aPoint.y aPoint.z 1 |
*/
void Translate(const Point3D& aPoint);
/**
* Skew the matrix.
*
* This creates this temporary matrix:
* | 1 tan(aYSkew) 0 0 |
* | tan(aXSkew) 1 0 0 |
* | 0 0 1 0 |
* | 0 0 0 1 |
*/
void SkewXY(double aXSkew, double aYSkew);
/**
* Scale the matrix
*
* This creates this temporary matrix:
* | aX 0 0 0 |
* | 0 aY 0 0 |
* | 0 0 aZ 0 |
* | 0 0 0 1 |
*/
void Scale(float aX, float aY, float aZ);
/**
* Return the currently set scaling factors.
*/
float GetXScale() const { return _11; }
float GetYScale() const { return _22; }
float GetZScale() const { return _33; }
/**
* Rotate around the X axis..
*
* This creates this temporary matrix:
* | 1 0 0 0 |
* | 0 cos(aTheta) sin(aTheta) 0 |
* | 0 -sin(aTheta) cos(aTheta) 0 |
* | 0 0 0 1 |
*/
void RotateX(double aTheta);
/**
* Rotate around the Y axis..
*
* This creates this temporary matrix:
* | cos(aTheta) 0 -sin(aTheta) 0 |
* | 0 1 0 0 |
* | sin(aTheta) 0 cos(aTheta) 0 |
* | 0 0 0 1 |
*/
void RotateY(double aTheta);
/**
* Rotate around the Z axis..
*
* This creates this temporary matrix:
* | cos(aTheta) sin(aTheta) 0 0 |
* | -sin(aTheta) cos(aTheta) 0 0 |
* | 0 0 1 0 |
* | 0 0 0 1 |
*/
void RotateZ(double aTheta);
/**
* Apply perspective to the matrix.
*
* This creates this temporary matrix:
* | 1 0 0 0 |
* | 0 1 0 0 |
* | 0 0 1 -1/aDepth |
* | 0 0 0 1 |
*/
void Perspective(float aDepth);
/**
* Pre multiply an existing matrix onto the current
* matrix
*/
void PreMultiply(const gfx3DMatrix& aOther);
void PreMultiply(const gfxMatrix& aOther);
/**
* Post-multiplication transformation functions:
*
* These functions construct a temporary matrix containing
* a single transformation and post-multiply it onto the current
* matrix.
*/
/**
* Add a translation by aPoint after the matrix.
* This is functionally equivalent to:
* matrix * gfx3DMatrix::Translation(aPoint)
*/
void TranslatePost(const Point3D& aPoint);
void ScalePost(float aX, float aY, float aZ);
/**
* Let T be the transformation matrix translating points in the coordinate
* space with origin aOrigin to the coordinate space used by this matrix.
* If this matrix is M, this function changes it to be (T-1)MT, the matrix
* that's equivalent to M but in the coordinate space that treats aOrigin
* as the origin.
*
* @param aOrigin The origin to translate to
* @return The modified matrix
*/
void ChangeBasis(const Point3D& aOrigin);
/**
* Transforms a point according to this matrix.
*/
gfxPoint Transform(const gfxPoint& point) const;
/**
* Transforms a rectangle according to this matrix
*/
gfxRect TransformBounds(const gfxRect& rect) const;
gfxQuad TransformRect(const gfxRect& aRect) const;
/**
* Transforms a 3D vector according to this matrix.
*/
Point3D Transform3D(const Point3D& point) const;
Point4D Transform4D(const Point4D& aPoint) const;
/**
* Given a point (x,y) find a value for z such that (x,y,z,1) transforms
* into (x',y',0,w') and returns the latter.
*/
Point4D ProjectPoint(const gfxPoint& aPoint) const;
/**
* Inverts this matrix, if possible. Otherwise, the matrix is left
* unchanged.
*/
gfx3DMatrix Inverse() const;
gfx3DMatrix& Invert()
{
*this = Inverse();
return *this;
}
/**
* Returns a unit vector that is perpendicular to the plane formed
* by transform the screen plane (z=0) by this matrix.
*/
Point3D GetNormalVector() const;
/**
* Returns true if a plane transformed by this matrix will
* have it's back face visible.
*/
bool IsBackfaceVisible() const;
/**
* Check if matrix is singular (no inverse exists).
*/
bool IsSingular() const;
/**
* Create a translation matrix.
*
* \param aX Translation on X-axis.
* \param aY Translation on Y-axis.
* \param aZ Translation on Z-axis.
*/
static gfx3DMatrix Translation(float aX, float aY, float aZ);
static gfx3DMatrix Translation(const Point3D& aPoint);
/**
* Create a scale matrix. Scales uniformly along all axes.
*
* \param aScale Scale factor
*/
static gfx3DMatrix ScalingMatrix(float aFactor);
/**
* Create a scale matrix.
*/
static gfx3DMatrix ScalingMatrix(float aX, float aY, float aZ);
gfxFloat Determinant() const;
void NudgeToIntegers(void);
void NudgeToIntegersFixedEpsilon();
private:
gfxFloat Determinant3x3() const;
gfx3DMatrix Inverse3x3() const;
gfx3DMatrix Multiply2D(const gfx3DMatrix &aMatrix) const;
public:
/** Matrix elements */
float _11, _12, _13, _14;
float _21, _22, _23, _24;
float _31, _32, _33, _34;
float _41, _42, _43, _44;
};
#endif /* GFX_3DMATRIX_H */