1/*
2 * Copyright 2011 Google Inc.
3 *
4 * Use of this source code is governed by a BSD-style license that can be
5 * found in the LICENSE file.
6 */
7
8#ifndef SkMatrix44_DEFINED
9#define SkMatrix44_DEFINED
10
11#include "SkMatrix.h"
12#include "SkScalar.h"
13
14#ifdef SK_MSCALAR_IS_DOUBLE
15#ifdef SK_MSCALAR_IS_FLOAT
16    #error "can't define MSCALAR both as DOUBLE and FLOAT"
17#endif
18    typedef double SkMScalar;
19
20    static inline double SkFloatToMScalar(float x) {
21        return static_cast<double>(x);
22    }
23    static inline float SkMScalarToFloat(double x) {
24        return static_cast<float>(x);
25    }
26    static inline double SkDoubleToMScalar(double x) {
27        return x;
28    }
29    static inline double SkMScalarToDouble(double x) {
30        return x;
31    }
32    static const SkMScalar SK_MScalarPI = 3.141592653589793;
33#elif defined SK_MSCALAR_IS_FLOAT
34#ifdef SK_MSCALAR_IS_DOUBLE
35    #error "can't define MSCALAR both as DOUBLE and FLOAT"
36#endif
37    typedef float SkMScalar;
38
39    static inline float SkFloatToMScalar(float x) {
40        return x;
41    }
42    static inline float SkMScalarToFloat(float x) {
43        return x;
44    }
45    static inline float SkDoubleToMScalar(double x) {
46        return static_cast<float>(x);
47    }
48    static inline double SkMScalarToDouble(float x) {
49        return static_cast<double>(x);
50    }
51    static const SkMScalar SK_MScalarPI = 3.14159265f;
52#endif
53
54#define SkMScalarToScalar SkMScalarToFloat
55#define SkScalarToMScalar SkFloatToMScalar
56
57static const SkMScalar SK_MScalar1 = 1;
58
59///////////////////////////////////////////////////////////////////////////////
60
61struct SkVector4 {
62    SkScalar fData[4];
63
64    SkVector4() {
65        this->set(0, 0, 0, 1);
66    }
67    SkVector4(const SkVector4& src) {
68        memcpy(fData, src.fData, sizeof(fData));
69    }
70    SkVector4(SkScalar x, SkScalar y, SkScalar z, SkScalar w = SK_Scalar1) {
71        fData[0] = x;
72        fData[1] = y;
73        fData[2] = z;
74        fData[3] = w;
75    }
76
77    SkVector4& operator=(const SkVector4& src) {
78        memcpy(fData, src.fData, sizeof(fData));
79        return *this;
80    }
81
82    bool operator==(const SkVector4& v) {
83        return fData[0] == v.fData[0] && fData[1] == v.fData[1] &&
84               fData[2] == v.fData[2] && fData[3] == v.fData[3];
85    }
86    bool operator!=(const SkVector4& v) {
87        return !(*this == v);
88    }
89    bool equals(SkScalar x, SkScalar y, SkScalar z, SkScalar w = SK_Scalar1) {
90        return fData[0] == x && fData[1] == y &&
91               fData[2] == z && fData[3] == w;
92    }
93
94    void set(SkScalar x, SkScalar y, SkScalar z, SkScalar w = SK_Scalar1) {
95        fData[0] = x;
96        fData[1] = y;
97        fData[2] = z;
98        fData[3] = w;
99    }
100};
101
102class SK_API SkMatrix44 {
103public:
104
105    enum Uninitialized_Constructor {
106        kUninitialized_Constructor
107    };
108    enum Identity_Constructor {
109        kIdentity_Constructor
110    };
111
112    SkMatrix44(Uninitialized_Constructor) { }
113    SkMatrix44(Identity_Constructor) { this->setIdentity(); }
114
115    SK_ATTR_DEPRECATED("use the constructors that take an enum")
116    SkMatrix44() { this->setIdentity(); }
117
118    SkMatrix44(const SkMatrix44& src) {
119        memcpy(fMat, src.fMat, sizeof(fMat));
120        fTypeMask = src.fTypeMask;
121    }
122
123    SkMatrix44(const SkMatrix44& a, const SkMatrix44& b) {
124        this->setConcat(a, b);
125    }
126
127    SkMatrix44& operator=(const SkMatrix44& src) {
128        if (&src != this) {
129            memcpy(fMat, src.fMat, sizeof(fMat));
130            fTypeMask = src.fTypeMask;
131        }
132        return *this;
133    }
134
135    bool operator==(const SkMatrix44& other) const;
136    bool operator!=(const SkMatrix44& other) const {
137        return !(other == *this);
138    }
139
140    /* When converting from SkMatrix44 to SkMatrix, the third row and
141     * column is dropped.  When converting from SkMatrix to SkMatrix44
142     * the third row and column remain as identity:
143     * [ a b c ]      [ a b 0 c ]
144     * [ d e f ]  ->  [ d e 0 f ]
145     * [ g h i ]      [ 0 0 1 0 ]
146     *                [ g h 0 i ]
147     */
148    SkMatrix44(const SkMatrix&);
149    SkMatrix44& operator=(const SkMatrix& src);
150    operator SkMatrix() const;
151
152    /**
153     *  Return a reference to a const identity matrix
154     */
155    static const SkMatrix44& I();
156
157    enum TypeMask {
158        kIdentity_Mask      = 0,
159        kTranslate_Mask     = 0x01,  //!< set if the matrix has translation
160        kScale_Mask         = 0x02,  //!< set if the matrix has any scale != 1
161        kAffine_Mask        = 0x04,  //!< set if the matrix skews or rotates
162        kPerspective_Mask   = 0x08   //!< set if the matrix is in perspective
163    };
164
165    /**
166     *  Returns a bitfield describing the transformations the matrix may
167     *  perform. The bitfield is computed conservatively, so it may include
168     *  false positives. For example, when kPerspective_Mask is true, all
169     *  other bits may be set to true even in the case of a pure perspective
170     *  transform.
171     */
172    inline TypeMask getType() const {
173        if (fTypeMask & kUnknown_Mask) {
174            fTypeMask = this->computeTypeMask();
175        }
176        SkASSERT(!(fTypeMask & kUnknown_Mask));
177        return (TypeMask)fTypeMask;
178    }
179
180    /**
181     *  Return true if the matrix is identity.
182     */
183    inline bool isIdentity() const {
184        return kIdentity_Mask == this->getType();
185    }
186
187    /**
188     *  Return true if the matrix contains translate or is identity.
189     */
190    inline bool isTranslate() const {
191        return !(this->getType() & ~kTranslate_Mask);
192    }
193
194    /**
195     *  Return true if the matrix only contains scale or translate or is identity.
196     */
197    inline bool isScaleTranslate() const {
198        return !(this->getType() & ~(kScale_Mask | kTranslate_Mask));
199    }
200
201    void setIdentity();
202    inline void reset() { this->setIdentity();}
203
204    /**
205     *  get a value from the matrix. The row,col parameters work as follows:
206     *  (0, 0)  scale-x
207     *  (0, 3)  translate-x
208     *  (3, 0)  perspective-x
209     */
210    inline SkMScalar get(int row, int col) const {
211        SkASSERT((unsigned)row <= 3);
212        SkASSERT((unsigned)col <= 3);
213        return fMat[col][row];
214    }
215
216    /**
217     *  set a value in the matrix. The row,col parameters work as follows:
218     *  (0, 0)  scale-x
219     *  (0, 3)  translate-x
220     *  (3, 0)  perspective-x
221     */
222    inline void set(int row, int col, SkMScalar value) {
223        SkASSERT((unsigned)row <= 3);
224        SkASSERT((unsigned)col <= 3);
225        fMat[col][row] = value;
226        this->dirtyTypeMask();
227    }
228
229    inline double getDouble(int row, int col) const {
230        return SkMScalarToDouble(this->get(row, col));
231    }
232    inline void setDouble(int row, int col, double value) {
233        this->set(row, col, SkDoubleToMScalar(value));
234    }
235    inline float getFloat(int row, int col) const {
236        return SkMScalarToFloat(this->get(row, col));
237    }
238    inline void setFloat(int row, int col, float value) {
239        this->set(row, col, SkFloatToMScalar(value));
240    }
241
242    /** These methods allow one to efficiently read matrix entries into an
243     *  array. The given array must have room for exactly 16 entries. Whenever
244     *  possible, they will try to use memcpy rather than an entry-by-entry
245     *  copy.
246     */
247    void asColMajorf(float[]) const;
248    void asColMajord(double[]) const;
249    void asRowMajorf(float[]) const;
250    void asRowMajord(double[]) const;
251
252    /** These methods allow one to efficiently set all matrix entries from an
253     *  array. The given array must have room for exactly 16 entries. Whenever
254     *  possible, they will try to use memcpy rather than an entry-by-entry
255     *  copy.
256     */
257    void setColMajorf(const float[]);
258    void setColMajord(const double[]);
259    void setRowMajorf(const float[]);
260    void setRowMajord(const double[]);
261
262#ifdef SK_MSCALAR_IS_FLOAT
263    void setColMajor(const SkMScalar data[]) { this->setColMajorf(data); }
264    void setRowMajor(const SkMScalar data[]) { this->setRowMajorf(data); }
265#else
266    void setColMajor(const SkMScalar data[]) { this->setColMajord(data); }
267    void setRowMajor(const SkMScalar data[]) { this->setRowMajord(data); }
268#endif
269
270    /* This sets the top-left of the matrix and clears the translation and
271     * perspective components (with [3][3] set to 1). */
272    void set3x3(SkMScalar m00, SkMScalar m01, SkMScalar m02,
273                SkMScalar m10, SkMScalar m11, SkMScalar m12,
274                SkMScalar m20, SkMScalar m21, SkMScalar m22);
275
276    void setTranslate(SkMScalar dx, SkMScalar dy, SkMScalar dz);
277    void preTranslate(SkMScalar dx, SkMScalar dy, SkMScalar dz);
278    void postTranslate(SkMScalar dx, SkMScalar dy, SkMScalar dz);
279
280    void setScale(SkMScalar sx, SkMScalar sy, SkMScalar sz);
281    void preScale(SkMScalar sx, SkMScalar sy, SkMScalar sz);
282    void postScale(SkMScalar sx, SkMScalar sy, SkMScalar sz);
283
284    inline void setScale(SkMScalar scale) {
285        this->setScale(scale, scale, scale);
286    }
287    inline void preScale(SkMScalar scale) {
288        this->preScale(scale, scale, scale);
289    }
290    inline void postScale(SkMScalar scale) {
291        this->postScale(scale, scale, scale);
292    }
293
294    void setRotateDegreesAbout(SkMScalar x, SkMScalar y, SkMScalar z,
295                               SkMScalar degrees) {
296        this->setRotateAbout(x, y, z, degrees * SK_MScalarPI / 180);
297    }
298
299    /** Rotate about the vector [x,y,z]. If that vector is not unit-length,
300        it will be automatically resized.
301     */
302    void setRotateAbout(SkMScalar x, SkMScalar y, SkMScalar z,
303                        SkMScalar radians);
304    /** Rotate about the vector [x,y,z]. Does not check the length of the
305        vector, assuming it is unit-length.
306     */
307    void setRotateAboutUnit(SkMScalar x, SkMScalar y, SkMScalar z,
308                            SkMScalar radians);
309
310    void setConcat(const SkMatrix44& a, const SkMatrix44& b);
311    inline void preConcat(const SkMatrix44& m) {
312        this->setConcat(*this, m);
313    }
314    inline void postConcat(const SkMatrix44& m) {
315        this->setConcat(m, *this);
316    }
317
318    friend SkMatrix44 operator*(const SkMatrix44& a, const SkMatrix44& b) {
319        return SkMatrix44(a, b);
320    }
321
322    /** If this is invertible, return that in inverse and return true. If it is
323        not invertible, return false and ignore the inverse parameter.
324     */
325    bool invert(SkMatrix44* inverse) const;
326
327    /** Transpose this matrix in place. */
328    void transpose();
329
330    /** Apply the matrix to the src vector, returning the new vector in dst.
331        It is legal for src and dst to point to the same memory.
332     */
333    void mapScalars(const SkScalar src[4], SkScalar dst[4]) const;
334    inline void mapScalars(SkScalar vec[4]) const {
335        this->mapScalars(vec, vec);
336    }
337
338    SK_ATTR_DEPRECATED("use mapScalars")
339    void map(const SkScalar src[4], SkScalar dst[4]) const {
340        this->mapScalars(src, dst);
341    }
342
343    SK_ATTR_DEPRECATED("use mapScalars")
344    void map(SkScalar vec[4]) const {
345        this->mapScalars(vec, vec);
346    }
347
348#ifdef SK_MSCALAR_IS_DOUBLE
349    void mapMScalars(const SkMScalar src[4], SkMScalar dst[4]) const;
350#elif defined SK_MSCALAR_IS_FLOAT
351    inline void mapMScalars(const SkMScalar src[4], SkMScalar dst[4]) const {
352        this->mapScalars(src, dst);
353    }
354#endif
355    inline void mapMScalars(SkMScalar vec[4]) const {
356        this->mapMScalars(vec, vec);
357    }
358
359    friend SkVector4 operator*(const SkMatrix44& m, const SkVector4& src) {
360        SkVector4 dst;
361        m.mapScalars(src.fData, dst.fData);
362        return dst;
363    }
364
365    /**
366     *  map an array of [x, y, 0, 1] through the matrix, returning an array
367     *  of [x', y', z', w'].
368     *
369     *  @param src2     array of [x, y] pairs, with implied z=0 and w=1
370     *  @param count    number of [x, y] pairs in src2
371     *  @param dst4     array of [x', y', z', w'] quads as the output.
372     */
373    void map2(const float src2[], int count, float dst4[]) const;
374    void map2(const double src2[], int count, double dst4[]) const;
375
376    void dump() const;
377
378    double determinant() const;
379
380private:
381    SkMScalar           fMat[4][4];
382    mutable unsigned    fTypeMask;
383
384    enum {
385        kUnknown_Mask = 0x80,
386
387        kAllPublic_Masks = 0xF
388    };
389
390    SkMScalar transX() const { return fMat[3][0]; }
391    SkMScalar transY() const { return fMat[3][1]; }
392    SkMScalar transZ() const { return fMat[3][2]; }
393
394    SkMScalar scaleX() const { return fMat[0][0]; }
395    SkMScalar scaleY() const { return fMat[1][1]; }
396    SkMScalar scaleZ() const { return fMat[2][2]; }
397
398    SkMScalar perspX() const { return fMat[0][3]; }
399    SkMScalar perspY() const { return fMat[1][3]; }
400    SkMScalar perspZ() const { return fMat[2][3]; }
401
402    int computeTypeMask() const;
403
404    inline void dirtyTypeMask() {
405        fTypeMask = kUnknown_Mask;
406    }
407
408    inline void setTypeMask(int mask) {
409        SkASSERT(0 == (~(kAllPublic_Masks | kUnknown_Mask) & mask));
410        fTypeMask = mask;
411    }
412
413    /**
414     *  Does not take the time to 'compute' the typemask. Only returns true if
415     *  we already know that this matrix is identity.
416     */
417    inline bool isTriviallyIdentity() const {
418        return 0 == fTypeMask;
419    }
420};
421
422#endif
423