1/*
2 * Copyright (C) 2006 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17
18
19//  Inspired by Rob Johnson's most excellent QuickDraw GX sample code
20
21#ifndef SkCamera_DEFINED
22#define SkCamera_DEFINED
23
24#include "Sk64.h"
25#include "SkMatrix.h"
26
27class SkCanvas;
28
29#ifdef SK_SCALAR_IS_FIXED
30    typedef SkFract SkUnitScalar;
31    #define SK_UnitScalar1          SK_Fract1
32    #define SkUnitScalarMul(a, b)   SkFractMul(a, b)
33    #define SkUnitScalarDiv(a, b)   SkFractDiv(a, b)
34#else
35    typedef float   SkUnitScalar;
36    #define SK_UnitScalar1          SK_Scalar1
37    #define SkUnitScalarMul(a, b)   SkScalarMul(a, b)
38    #define SkUnitScalarDiv(a, b)   SkScalarDiv(a, b)
39#endif
40
41struct SkUnit3D {
42    SkUnitScalar    fX, fY, fZ;
43
44    void set(SkUnitScalar x, SkUnitScalar y, SkUnitScalar z)
45    {
46        fX = x; fY = y; fZ = z;
47    }
48    static SkUnitScalar Dot(const SkUnit3D&, const SkUnit3D&);
49    static void Cross(const SkUnit3D&, const SkUnit3D&, SkUnit3D* cross);
50};
51
52struct SkPoint3D {
53    SkScalar    fX, fY, fZ;
54
55    void set(SkScalar x, SkScalar y, SkScalar z)
56    {
57        fX = x; fY = y; fZ = z;
58    }
59    SkScalar    normalize(SkUnit3D*) const;
60};
61typedef SkPoint3D SkVector3D;
62
63struct SkMatrix3D {
64    SkScalar    fMat[3][4];
65
66    void reset();
67
68    void setRow(int row, SkScalar a, SkScalar b, SkScalar c, SkScalar d = 0)
69    {
70        SkASSERT((unsigned)row < 3);
71        fMat[row][0] = a;
72        fMat[row][1] = b;
73        fMat[row][2] = c;
74        fMat[row][3] = d;
75    }
76
77    void setRotateX(SkScalar deg);
78    void setRotateY(SkScalar deg);
79    void setRotateZ(SkScalar deg);
80    void setTranslate(SkScalar x, SkScalar y, SkScalar z);
81
82    void preRotateX(SkScalar deg);
83    void preRotateY(SkScalar deg);
84    void preRotateZ(SkScalar deg);
85    void preTranslate(SkScalar x, SkScalar y, SkScalar z);
86
87    void setConcat(const SkMatrix3D& a, const SkMatrix3D& b);
88    void mapPoint(const SkPoint3D& src, SkPoint3D* dst) const;
89    void mapVector(const SkVector3D& src, SkVector3D* dst) const;
90
91    void mapPoint(SkPoint3D* v) const
92    {
93        this->mapPoint(*v, v);
94    }
95    void mapVector(SkVector3D* v) const
96    {
97        this->mapVector(*v, v);
98    }
99};
100
101class SkPatch3D {
102public:
103    SkPatch3D();
104
105    void    reset();
106    void    transform(const SkMatrix3D&, SkPatch3D* dst = NULL) const;
107
108    // dot a unit vector with the patch's normal
109    SkScalar dotWith(SkScalar dx, SkScalar dy, SkScalar dz) const;
110    SkScalar dotWith(const SkVector3D& v) const
111    {
112        return this->dotWith(v.fX, v.fY, v.fZ);
113    }
114
115    // depreicated, but still here for animator (for now)
116    void rotate(SkScalar x, SkScalar y, SkScalar z) {}
117    void rotateDegrees(SkScalar x, SkScalar y, SkScalar z) {}
118
119private:
120public: // make public for SkDraw3D for now
121    SkVector3D  fU, fV;
122    SkPoint3D   fOrigin;
123
124    friend class SkCamera3D;
125};
126
127class SkCamera3D {
128public:
129    SkCamera3D();
130
131    void reset();
132    void update();
133    void patchToMatrix(const SkPatch3D&, SkMatrix* matrix) const;
134
135    SkPoint3D   fLocation;
136    SkPoint3D   fAxis;
137    SkPoint3D   fZenith;
138    SkPoint3D   fObserver;
139
140private:
141    mutable SkMatrix    fOrientation;
142    mutable bool        fNeedToUpdate;
143
144    void doUpdate() const;
145};
146
147class Sk3DView : SkNoncopyable {
148public:
149    Sk3DView();
150    ~Sk3DView();
151
152    void save();
153    void restore();
154
155    void translate(SkScalar x, SkScalar y, SkScalar z);
156    void rotateX(SkScalar deg);
157    void rotateY(SkScalar deg);
158    void rotateZ(SkScalar deg);
159
160    void getMatrix(SkMatrix*) const;
161    void applyToCanvas(SkCanvas*) const;
162
163    SkScalar dotWithNormal(SkScalar dx, SkScalar dy, SkScalar dz) const;
164
165private:
166    struct Rec {
167        Rec*        fNext;
168        SkMatrix3D  fMatrix;
169    };
170    Rec*        fRec;
171    Rec         fInitialRec;
172    SkCamera3D  fCamera;
173};
174
175#endif
176
177