robertphillips | 3d32d76 | 2015-07-13 13:16:44 -0700 | [diff] [blame] | 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 "SkScalar.h" |
| 12 | |
| 13 | struct SK_API SkPoint3 { |
| 14 | SkScalar fX, fY, fZ; |
| 15 | |
| 16 | #ifdef SK_LEGACY_SKPOINT3_CTORS |
| 17 | // TODO: remove these - they are needed for Chromium staging |
| 18 | SkPoint3() {} |
| 19 | SkPoint3(SkScalar x, SkScalar y, SkScalar z) : fX(x), fY(y), fZ(z) {} |
| 20 | #endif |
| 21 | |
| 22 | static SkPoint3 Make(SkScalar x, SkScalar y, SkScalar z) { |
| 23 | SkPoint3 pt; |
| 24 | pt.set(x, y, z); |
| 25 | return pt; |
| 26 | } |
| 27 | |
| 28 | SkScalar x() const { return fX; } |
| 29 | SkScalar y() const { return fY; } |
| 30 | SkScalar z() const { return fZ; } |
| 31 | |
| 32 | void set(SkScalar x, SkScalar y, SkScalar z) { fX = x; fY = y; fZ = z; } |
| 33 | |
| 34 | friend bool operator==(const SkPoint3& a, const SkPoint3& b) { |
| 35 | return a.fX == b.fX && a.fY == b.fY && a.fZ == b.fZ; |
| 36 | } |
| 37 | |
| 38 | friend bool operator!=(const SkPoint3& a, const SkPoint3& b) { |
| 39 | return !(a == b); |
| 40 | } |
| 41 | |
| 42 | /** Returns the Euclidian distance from (0,0,0) to (x,y,z) |
| 43 | */ |
| 44 | static SkScalar Length(SkScalar x, SkScalar y, SkScalar z); |
| 45 | |
| 46 | /** Return the Euclidian distance from (0,0,0) to the point |
| 47 | */ |
| 48 | SkScalar length() const { return SkPoint3::Length(fX, fY, fZ); } |
| 49 | |
| 50 | /** Set the point (vector) to be unit-length in the same direction as it |
| 51 | already points. If the point has a degenerate length (i.e., nearly 0) |
| 52 | then set it to (0,0,0) and return false; otherwise return true. |
| 53 | */ |
| 54 | bool normalize(); |
| 55 | |
| 56 | /** Return a new point whose X, Y and Z coordinates are scaled. |
| 57 | */ |
| 58 | SkPoint3 makeScale(SkScalar scale) const { |
| 59 | SkPoint3 p; |
| 60 | p.set(scale * fX, scale * fY, scale * fZ); |
| 61 | return p; |
| 62 | } |
| 63 | |
| 64 | /** Scale the point's coordinates by scale. |
| 65 | */ |
| 66 | void scale(SkScalar value) { |
| 67 | fX *= value; |
| 68 | fY *= value; |
| 69 | fZ *= value; |
| 70 | } |
| 71 | |
| 72 | /** Return a new point whose X, Y and Z coordinates are the negative of the |
| 73 | original point's |
| 74 | */ |
| 75 | SkPoint3 operator-() const { |
| 76 | SkPoint3 neg; |
| 77 | neg.fX = -fX; |
| 78 | neg.fY = -fY; |
| 79 | neg.fZ = -fZ; |
| 80 | return neg; |
| 81 | } |
| 82 | |
| 83 | /** Returns a new point whose coordinates are the difference between |
| 84 | a and b (i.e., a - b) |
| 85 | */ |
| 86 | friend SkPoint3 operator-(const SkPoint3& a, const SkPoint3& b) { |
| 87 | SkPoint3 v; |
| 88 | v.set(a.fX - b.fX, a.fY - b.fY, a.fZ - b.fZ); |
| 89 | return v; |
| 90 | } |
| 91 | |
| 92 | /** Returns a new point whose coordinates are the sum of a and b (a + b) |
| 93 | */ |
| 94 | friend SkPoint3 operator+(const SkPoint3& a, const SkPoint3& b) { |
| 95 | SkPoint3 v; |
| 96 | v.set(a.fX + b.fX, a.fY + b.fY, a.fZ + b.fZ); |
| 97 | return v; |
| 98 | } |
| 99 | |
| 100 | /** Returns the dot product of a and b, treating them as 3D vectors |
| 101 | */ |
| 102 | static SkScalar DotProduct(const SkPoint3& a, const SkPoint3& b) { |
| 103 | return a.fX * b.fX + a.fY * b.fY + a.fZ * b.fZ; |
| 104 | } |
| 105 | |
| 106 | SkScalar dot(const SkPoint3& vec) const { |
| 107 | return DotProduct(*this, vec); |
| 108 | } |
| 109 | }; |
| 110 | |
| 111 | typedef SkPoint3 SkVector3; |
| 112 | |
| 113 | #endif |