gecko-dev/gfx/thebes/gfx3DMatrix.h

365 lines
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C++

/* -*- 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 <gfxPoint3D.h>
#include <gfxPointH3D.h>
#include <gfxQuad.h>
struct 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
{
public:
/**
* Create matrix.
*/
gfx3DMatrix(void);
/**
* Matrix multiplication.
*/
gfx3DMatrix operator*(const gfx3DMatrix &aMatrix) const;
gfx3DMatrix& operator*=(const gfx3DMatrix &aMatrix);
gfxPointH3D& operator[](int aIndex)
{
NS_ABORT_IF_FALSE(aIndex >= 0 && aIndex <= 3, "Invalid matrix array index");
return *reinterpret_cast<gfxPointH3D*>((&_11)+4*aIndex);
}
const gfxPointH3D& operator[](int aIndex) const
{
NS_ABORT_IF_FALSE(aIndex >= 0 && aIndex <= 3, "Invalid matrix array index");
return *reinterpret_cast<const gfxPointH3D*>((&_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 gfxPoint3D& 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);
void SkewXY(double aSkew);
void SkewXZ(double aSkew);
void SkewYZ(double aSkew);
/**
* 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 gfxPoint3D& aPoint);
void ScalePost(float aX, float aY, float aZ);
/**
* 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.
*/
gfxPoint3D Transform3D(const gfxPoint3D& point) const;
gfxPointH3D Transform4D(const gfxPointH3D& aPoint) const;
gfxPointH3D TransposeTransform4D(const gfxPointH3D& aPoint) const;
gfxPoint ProjectPoint(const gfxPoint& aPoint) const;
gfxRect ProjectRectBounds(const gfxRect& aRect) const;
/**
* Transforms a point by the inverse of this matrix. In the case of perspective transforms, some screen
* points have no equivalent in the untransformed plane (if they exist past the vanishing point). To
* avoid this, we need to specify the bounds of the untransformed plane to restrict the search area.
*
* @param aPoint Point to untransform.
* @param aChildBounds Bounds of the untransformed plane.
* @param aOut Untransformed point.
* @return Returns true if a point was found within a ChildBounds, false otherwise.
*/
bool UntransformPoint(const gfxPoint& aPoint, const gfxRect& aChildBounds, gfxPoint* aOut) const;
/**
* Same as UntransformPoint, but untransforms a rect and returns the bounding rect of the result.
* Returns an empty rect if the result doesn't intersect aChildBounds.
*/
gfxRect UntransformBounds(const gfxRect& aRect, const gfxRect& aChildBounds) const;
/**
* Inverts this matrix, if possible. Otherwise, the matrix is left
* unchanged.
*/
gfx3DMatrix Inverse() const;
gfx3DMatrix& Invert()
{
*this = Inverse();
return *this;
}
gfx3DMatrix& Normalize();
gfxPointH3D TransposedVector(int aIndex) const
{
NS_ABORT_IF_FALSE(aIndex >= 0 && aIndex <= 3, "Invalid matrix array index");
return gfxPointH3D(*((&_11)+aIndex), *((&_21)+aIndex), *((&_31)+aIndex), *((&_41)+aIndex));
}
void SetTransposedVector(int aIndex, gfxPointH3D &aVector)
{
NS_ABORT_IF_FALSE(aIndex >= 0 && aIndex <= 3, "Invalid matrix array index");
*((&_11)+aIndex) = aVector.x;
*((&_21)+aIndex) = aVector.y;
*((&_31)+aIndex) = aVector.z;
*((&_41)+aIndex) = aVector.w;
}
gfx3DMatrix& Transpose();
gfx3DMatrix Transposed() const;
/**
* Returns a unit vector that is perpendicular to the plane formed
* by transform the screen plane (z=0) by this matrix.
*/
gfxPoint3D 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 gfxPoint3D& 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);
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 */