1 /* 2 * Copyright 2015 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 SkPoint3_DEFINED 9 #define SkPoint3_DEFINED 10 11 #include "include/core/SkScalar.h" 12 #include "include/private/base/SkAPI.h" 13 #include "include/private/base/SkFloatingPoint.h" 14 15 struct SK_API SkPoint3 { 16 SkScalar fX, fY, fZ; 17 MakeSkPoint318 static SkPoint3 Make(SkScalar x, SkScalar y, SkScalar z) { 19 SkPoint3 pt; 20 pt.set(x, y, z); 21 return pt; 22 } 23 xSkPoint324 SkScalar x() const { return fX; } ySkPoint325 SkScalar y() const { return fY; } zSkPoint326 SkScalar z() const { return fZ; } 27 setSkPoint328 void set(SkScalar x, SkScalar y, SkScalar z) { fX = x; fY = y; fZ = z; } 29 30 friend bool operator==(const SkPoint3& a, const SkPoint3& b) { 31 return a.fX == b.fX && a.fY == b.fY && a.fZ == b.fZ; 32 } 33 34 friend bool operator!=(const SkPoint3& a, const SkPoint3& b) { 35 return !(a == b); 36 } 37 38 /** Returns the Euclidian distance from (0,0,0) to (x,y,z) 39 */ 40 static SkScalar Length(SkScalar x, SkScalar y, SkScalar z); 41 42 /** Return the Euclidian distance from (0,0,0) to the point 43 */ lengthSkPoint344 SkScalar length() const { return SkPoint3::Length(fX, fY, fZ); } 45 46 /** Set the point (vector) to be unit-length in the same direction as it 47 already points. If the point has a degenerate length (i.e., nearly 0) 48 then set it to (0,0,0) and return false; otherwise return true. 49 */ 50 bool normalize(); 51 52 /** Return a new point whose X, Y and Z coordinates are scaled. 53 */ makeScaleSkPoint354 SkPoint3 makeScale(SkScalar scale) const { 55 SkPoint3 p; 56 p.set(scale * fX, scale * fY, scale * fZ); 57 return p; 58 } 59 60 /** Scale the point's coordinates by scale. 61 */ scaleSkPoint362 void scale(SkScalar value) { 63 fX *= value; 64 fY *= value; 65 fZ *= value; 66 } 67 68 /** Return a new point whose X, Y and Z coordinates are the negative of the 69 original point's 70 */ 71 SkPoint3 operator-() const { 72 SkPoint3 neg; 73 neg.fX = -fX; 74 neg.fY = -fY; 75 neg.fZ = -fZ; 76 return neg; 77 } 78 79 /** Returns a new point whose coordinates are the difference between 80 a and b (i.e., a - b) 81 */ 82 friend SkPoint3 operator-(const SkPoint3& a, const SkPoint3& b) { 83 return { a.fX - b.fX, a.fY - b.fY, a.fZ - b.fZ }; 84 } 85 86 /** Returns a new point whose coordinates are the sum of a and b (a + b) 87 */ 88 friend SkPoint3 operator+(const SkPoint3& a, const SkPoint3& b) { 89 return { a.fX + b.fX, a.fY + b.fY, a.fZ + b.fZ }; 90 } 91 92 /** Add v's coordinates to the point's 93 */ 94 void operator+=(const SkPoint3& v) { 95 fX += v.fX; 96 fY += v.fY; 97 fZ += v.fZ; 98 } 99 100 /** Subtract v's coordinates from the point's 101 */ 102 void operator-=(const SkPoint3& v) { 103 fX -= v.fX; 104 fY -= v.fY; 105 fZ -= v.fZ; 106 } 107 108 friend SkPoint3 operator*(SkScalar t, SkPoint3 p) { 109 return { t * p.fX, t * p.fY, t * p.fZ }; 110 } 111 112 /** Returns true if fX, fY, and fZ are measurable values. 113 114 @return true for values other than infinities and NaN 115 */ isFiniteSkPoint3116 bool isFinite() const { 117 return SkIsFinite(fX, fY, fZ); 118 } 119 120 /** Returns the dot product of a and b, treating them as 3D vectors 121 */ DotProductSkPoint3122 static SkScalar DotProduct(const SkPoint3& a, const SkPoint3& b) { 123 return a.fX * b.fX + a.fY * b.fY + a.fZ * b.fZ; 124 } 125 dotSkPoint3126 SkScalar dot(const SkPoint3& vec) const { 127 return DotProduct(*this, vec); 128 } 129 130 /** Returns the cross product of a and b, treating them as 3D vectors 131 */ CrossProductSkPoint3132 static SkPoint3 CrossProduct(const SkPoint3& a, const SkPoint3& b) { 133 SkPoint3 result; 134 result.fX = a.fY*b.fZ - a.fZ*b.fY; 135 result.fY = a.fZ*b.fX - a.fX*b.fZ; 136 result.fZ = a.fX*b.fY - a.fY*b.fX; 137 138 return result; 139 } 140 crossSkPoint3141 SkPoint3 cross(const SkPoint3& vec) const { 142 return CrossProduct(*this, vec); 143 } 144 }; 145 146 typedef SkPoint3 SkVector3; 147 typedef SkPoint3 SkColor3f; 148 149 #endif 150