skia2/include/core/SkMatrix44.h
Mason Freed 559d9eea48 Made the fTypeMask field non-lazily computed.
With this change, the SkMatrix44 is now trivially copyable. It will
do more work than before if multiple mutations are performed on a
matrix before the getType() method is called.

Bug: 938563
Change-Id: I3faf88e2b72de264457ebff61a26608baf3afd2e
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/206176
Commit-Queue: Florin Malita <fmalita@chromium.org>
Auto-Submit: Mason Freed <masonfreed@chromium.org>
Reviewed-by: Florin Malita <fmalita@chromium.org>
2019-04-05 21:16:10 +00:00

467 lines
15 KiB
C++

/*
* Copyright 2011 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef SkMatrix44_DEFINED
#define SkMatrix44_DEFINED
#include "SkMatrix.h"
#include "SkScalar.h"
#include <atomic>
#include <cstring>
#ifdef SK_MSCALAR_IS_DOUBLE
#ifdef SK_MSCALAR_IS_FLOAT
#error "can't define MSCALAR both as DOUBLE and FLOAT"
#endif
typedef double SkMScalar;
static inline double SkFloatToMScalar(float x) {
return static_cast<double>(x);
}
static inline float SkMScalarToFloat(double x) {
return static_cast<float>(x);
}
static inline double SkDoubleToMScalar(double x) {
return x;
}
static inline double SkMScalarToDouble(double x) {
return x;
}
static inline double SkMScalarAbs(double x) {
return fabs(x);
}
static const SkMScalar SK_MScalarPI = 3.141592653589793;
#define SkMScalarFloor(x) sk_double_floor(x)
#define SkMScalarCeil(x) sk_double_ceil(x)
#define SkMScalarRound(x) sk_double_round(x)
#define SkMScalarFloorToInt(x) sk_double_floor2int(x)
#define SkMScalarCeilToInt(x) sk_double_ceil2int(x)
#define SkMScalarRoundToInt(x) sk_double_round2int(x)
#elif defined SK_MSCALAR_IS_FLOAT
#ifdef SK_MSCALAR_IS_DOUBLE
#error "can't define MSCALAR both as DOUBLE and FLOAT"
#endif
typedef float SkMScalar;
static inline float SkFloatToMScalar(float x) {
return x;
}
static inline float SkMScalarToFloat(float x) {
return x;
}
static inline float SkDoubleToMScalar(double x) {
return sk_double_to_float(x);
}
static inline double SkMScalarToDouble(float x) {
return static_cast<double>(x);
}
static inline float SkMScalarAbs(float x) {
return sk_float_abs(x);
}
static const SkMScalar SK_MScalarPI = 3.14159265f;
#define SkMScalarFloor(x) sk_float_floor(x)
#define SkMScalarCeil(x) sk_float_ceil(x)
#define SkMScalarRound(x) sk_float_round(x)
#define SkMScalarFloorToInt(x) sk_float_floor2int(x)
#define SkMScalarCeilToInt(x) sk_float_ceil2int(x)
#define SkMScalarRoundToInt(x) sk_float_round2int(x)
#endif
#define SkIntToMScalar(n) static_cast<SkMScalar>(n)
#define SkMScalarToScalar(x) SkMScalarToFloat(x)
#define SkScalarToMScalar(x) SkFloatToMScalar(x)
static const SkMScalar SK_MScalar1 = 1;
///////////////////////////////////////////////////////////////////////////////
struct SkVector4 {
SkScalar fData[4];
SkVector4() {
this->set(0, 0, 0, 1);
}
SkVector4(const SkVector4& src) {
memcpy(fData, src.fData, sizeof(fData));
}
SkVector4(SkScalar x, SkScalar y, SkScalar z, SkScalar w = SK_Scalar1) {
fData[0] = x;
fData[1] = y;
fData[2] = z;
fData[3] = w;
}
SkVector4& operator=(const SkVector4& src) {
memcpy(fData, src.fData, sizeof(fData));
return *this;
}
bool operator==(const SkVector4& v) {
return fData[0] == v.fData[0] && fData[1] == v.fData[1] &&
fData[2] == v.fData[2] && fData[3] == v.fData[3];
}
bool operator!=(const SkVector4& v) {
return !(*this == v);
}
bool equals(SkScalar x, SkScalar y, SkScalar z, SkScalar w = SK_Scalar1) {
return fData[0] == x && fData[1] == y &&
fData[2] == z && fData[3] == w;
}
void set(SkScalar x, SkScalar y, SkScalar z, SkScalar w = SK_Scalar1) {
fData[0] = x;
fData[1] = y;
fData[2] = z;
fData[3] = w;
}
};
/** \class SkMatrix44
The SkMatrix44 class holds a 4x4 matrix.
*/
class SK_API SkMatrix44 {
public:
enum Uninitialized_Constructor {
kUninitialized_Constructor
};
enum Identity_Constructor {
kIdentity_Constructor
};
SkMatrix44(Uninitialized_Constructor) {} // ironically, cannot be constexpr
constexpr SkMatrix44(Identity_Constructor)
: fMat{{ 1, 0, 0, 0, },
{ 0, 1, 0, 0, },
{ 0, 0, 1, 0, },
{ 0, 0, 0, 1, }}
, fTypeMask(kIdentity_Mask)
{}
constexpr SkMatrix44() : SkMatrix44{kIdentity_Constructor} {}
SkMatrix44(const SkMatrix44& src) = default;
SkMatrix44& operator=(const SkMatrix44& src) = default;
SkMatrix44(const SkMatrix44& a, const SkMatrix44& b) {
this->setConcat(a, b);
}
bool operator==(const SkMatrix44& other) const;
bool operator!=(const SkMatrix44& other) const {
return !(other == *this);
}
/* When converting from SkMatrix44 to SkMatrix, the third row and
* column is dropped. When converting from SkMatrix to SkMatrix44
* the third row and column remain as identity:
* [ a b c ] [ a b 0 c ]
* [ d e f ] -> [ d e 0 f ]
* [ g h i ] [ 0 0 1 0 ]
* [ g h 0 i ]
*/
SkMatrix44(const SkMatrix&);
SkMatrix44& operator=(const SkMatrix& src);
operator SkMatrix() const;
/**
* Return a reference to a const identity matrix
*/
static const SkMatrix44& I();
using TypeMask = uint8_t;
enum : TypeMask {
kIdentity_Mask = 0,
kTranslate_Mask = 1 << 0, //!< set if the matrix has translation
kScale_Mask = 1 << 1, //!< set if the matrix has any scale != 1
kAffine_Mask = 1 << 2, //!< set if the matrix skews or rotates
kPerspective_Mask = 1 << 3, //!< set if the matrix is in perspective
};
/**
* Returns a bitfield describing the transformations the matrix may
* perform. The bitfield is computed conservatively, so it may include
* false positives. For example, when kPerspective_Mask is true, all
* other bits may be set to true even in the case of a pure perspective
* transform.
*/
inline TypeMask getType() const { return fTypeMask; }
/**
* Return true if the matrix is identity.
*/
inline bool isIdentity() const {
return kIdentity_Mask == this->getType();
}
/**
* Return true if the matrix contains translate or is identity.
*/
inline bool isTranslate() const {
return !(this->getType() & ~kTranslate_Mask);
}
/**
* Return true if the matrix only contains scale or translate or is identity.
*/
inline bool isScaleTranslate() const {
return !(this->getType() & ~(kScale_Mask | kTranslate_Mask));
}
/**
* Returns true if the matrix only contains scale or is identity.
*/
inline bool isScale() const {
return !(this->getType() & ~kScale_Mask);
}
inline bool hasPerspective() const {
return SkToBool(this->getType() & kPerspective_Mask);
}
void setIdentity();
inline void reset() { this->setIdentity();}
/**
* get a value from the matrix. The row,col parameters work as follows:
* (0, 0) scale-x
* (0, 3) translate-x
* (3, 0) perspective-x
*/
inline SkMScalar get(int row, int col) const {
SkASSERT((unsigned)row <= 3);
SkASSERT((unsigned)col <= 3);
return fMat[col][row];
}
/**
* set a value in the matrix. The row,col parameters work as follows:
* (0, 0) scale-x
* (0, 3) translate-x
* (3, 0) perspective-x
*/
inline void set(int row, int col, SkMScalar value) {
SkASSERT((unsigned)row <= 3);
SkASSERT((unsigned)col <= 3);
fMat[col][row] = value;
this->recomputeTypeMask();
}
inline double getDouble(int row, int col) const {
return SkMScalarToDouble(this->get(row, col));
}
inline void setDouble(int row, int col, double value) {
this->set(row, col, SkDoubleToMScalar(value));
}
inline float getFloat(int row, int col) const {
return SkMScalarToFloat(this->get(row, col));
}
inline void setFloat(int row, int col, float value) {
this->set(row, col, SkFloatToMScalar(value));
}
/** These methods allow one to efficiently read matrix entries into an
* array. The given array must have room for exactly 16 entries. Whenever
* possible, they will try to use memcpy rather than an entry-by-entry
* copy.
*
* Col major indicates that consecutive elements of columns will be stored
* contiguously in memory. Row major indicates that consecutive elements
* of rows will be stored contiguously in memory.
*/
void asColMajorf(float[]) const;
void asColMajord(double[]) const;
void asRowMajorf(float[]) const;
void asRowMajord(double[]) const;
/** These methods allow one to efficiently set all matrix entries from an
* array. The given array must have room for exactly 16 entries. Whenever
* possible, they will try to use memcpy rather than an entry-by-entry
* copy.
*
* Col major indicates that input memory will be treated as if consecutive
* elements of columns are stored contiguously in memory. Row major
* indicates that input memory will be treated as if consecutive elements
* of rows are stored contiguously in memory.
*/
void setColMajorf(const float[]);
void setColMajord(const double[]);
void setRowMajorf(const float[]);
void setRowMajord(const double[]);
#ifdef SK_MSCALAR_IS_FLOAT
void setColMajor(const SkMScalar data[]) { this->setColMajorf(data); }
void setRowMajor(const SkMScalar data[]) { this->setRowMajorf(data); }
#else
void setColMajor(const SkMScalar data[]) { this->setColMajord(data); }
void setRowMajor(const SkMScalar data[]) { this->setRowMajord(data); }
#endif
/* This sets the top-left of the matrix and clears the translation and
* perspective components (with [3][3] set to 1). m_ij is interpreted
* as the matrix entry at row = i, col = j. */
void set3x3(SkMScalar m_00, SkMScalar m_10, SkMScalar m_20,
SkMScalar m_01, SkMScalar m_11, SkMScalar m_21,
SkMScalar m_02, SkMScalar m_12, SkMScalar m_22);
void set3x3RowMajorf(const float[]);
void setTranslate(SkMScalar dx, SkMScalar dy, SkMScalar dz);
void preTranslate(SkMScalar dx, SkMScalar dy, SkMScalar dz);
void postTranslate(SkMScalar dx, SkMScalar dy, SkMScalar dz);
void setScale(SkMScalar sx, SkMScalar sy, SkMScalar sz);
void preScale(SkMScalar sx, SkMScalar sy, SkMScalar sz);
void postScale(SkMScalar sx, SkMScalar sy, SkMScalar sz);
inline void setScale(SkMScalar scale) {
this->setScale(scale, scale, scale);
}
inline void preScale(SkMScalar scale) {
this->preScale(scale, scale, scale);
}
inline void postScale(SkMScalar scale) {
this->postScale(scale, scale, scale);
}
void setRotateDegreesAbout(SkMScalar x, SkMScalar y, SkMScalar z,
SkMScalar degrees) {
this->setRotateAbout(x, y, z, degrees * SK_MScalarPI / 180);
}
/** Rotate about the vector [x,y,z]. If that vector is not unit-length,
it will be automatically resized.
*/
void setRotateAbout(SkMScalar x, SkMScalar y, SkMScalar z,
SkMScalar radians);
/** Rotate about the vector [x,y,z]. Does not check the length of the
vector, assuming it is unit-length.
*/
void setRotateAboutUnit(SkMScalar x, SkMScalar y, SkMScalar z,
SkMScalar radians);
void setConcat(const SkMatrix44& a, const SkMatrix44& b);
inline void preConcat(const SkMatrix44& m) {
this->setConcat(*this, m);
}
inline void postConcat(const SkMatrix44& m) {
this->setConcat(m, *this);
}
friend SkMatrix44 operator*(const SkMatrix44& a, const SkMatrix44& b) {
return SkMatrix44(a, b);
}
/** If this is invertible, return that in inverse and return true. If it is
not invertible, return false and leave the inverse parameter in an
unspecified state.
*/
bool invert(SkMatrix44* inverse) const;
/** Transpose this matrix in place. */
void transpose();
/** Apply the matrix to the src vector, returning the new vector in dst.
It is legal for src and dst to point to the same memory.
*/
void mapScalars(const SkScalar src[4], SkScalar dst[4]) const;
inline void mapScalars(SkScalar vec[4]) const {
this->mapScalars(vec, vec);
}
#ifdef SK_MSCALAR_IS_DOUBLE
void mapMScalars(const SkMScalar src[4], SkMScalar dst[4]) const;
#elif defined SK_MSCALAR_IS_FLOAT
inline void mapMScalars(const SkMScalar src[4], SkMScalar dst[4]) const {
this->mapScalars(src, dst);
}
#endif
inline void mapMScalars(SkMScalar vec[4]) const {
this->mapMScalars(vec, vec);
}
friend SkVector4 operator*(const SkMatrix44& m, const SkVector4& src) {
SkVector4 dst;
m.mapScalars(src.fData, dst.fData);
return dst;
}
/**
* map an array of [x, y, 0, 1] through the matrix, returning an array
* of [x', y', z', w'].
*
* @param src2 array of [x, y] pairs, with implied z=0 and w=1
* @param count number of [x, y] pairs in src2
* @param dst4 array of [x', y', z', w'] quads as the output.
*/
void map2(const float src2[], int count, float dst4[]) const;
void map2(const double src2[], int count, double dst4[]) const;
/** Returns true if transformating an axis-aligned square in 2d by this matrix
will produce another 2d axis-aligned square; typically means the matrix
is a scale with perhaps a 90-degree rotation. A 3d rotation through 90
degrees into a perpendicular plane collapses a square to a line, but
is still considered to be axis-aligned.
By default, tolerates very slight error due to float imprecisions;
a 90-degree rotation can still end up with 10^-17 of
"non-axis-aligned" result.
*/
bool preserves2dAxisAlignment(SkMScalar epsilon = SK_ScalarNearlyZero) const;
void dump() const;
double determinant() const;
private:
/* This is indexed by [col][row]. */
SkMScalar fMat[4][4];
TypeMask fTypeMask;
static constexpr int kAllPublic_Masks = 0xF;
void as3x4RowMajorf(float[]) const;
void set3x4RowMajorf(const float[]);
SkMScalar transX() const { return fMat[3][0]; }
SkMScalar transY() const { return fMat[3][1]; }
SkMScalar transZ() const { return fMat[3][2]; }
SkMScalar scaleX() const { return fMat[0][0]; }
SkMScalar scaleY() const { return fMat[1][1]; }
SkMScalar scaleZ() const { return fMat[2][2]; }
SkMScalar perspX() const { return fMat[0][3]; }
SkMScalar perspY() const { return fMat[1][3]; }
SkMScalar perspZ() const { return fMat[2][3]; }
void recomputeTypeMask();
inline void setTypeMask(TypeMask mask) {
SkASSERT(0 == (~kAllPublic_Masks & mask));
fTypeMask = mask;
}
inline const SkMScalar* values() const { return &fMat[0][0]; }
friend class SkColorSpace;
};
#endif