Line data Source code
1 : // Copyright (C) 2002-2012 Nikolaus Gebhardt
2 : // This file is part of the "Irrlicht Engine".
3 : // For conditions of distribution and use, see copyright notice in irrlicht.h
4 :
5 : #ifndef __IRR_LINE_3D_H_INCLUDED__
6 : #define __IRR_LINE_3D_H_INCLUDED__
7 :
8 : #include "irrTypes.h"
9 : #include "vector3d.h"
10 :
11 : namespace irr
12 : {
13 : namespace core
14 : {
15 :
16 : //! 3D line between two points with intersection methods.
17 : template <class T>
18 3498 : class line3d
19 : {
20 : public:
21 :
22 : //! Default constructor
23 : /** line from (0,0,0) to (1,1,1) */
24 1166 : line3d() : start(0,0,0), end(1,1,1) {}
25 : //! Constructor with two points
26 0 : line3d(T xa, T ya, T za, T xb, T yb, T zb) : start(xa, ya, za), end(xb, yb, zb) {}
27 : //! Constructor with two points as vectors
28 1166 : line3d(const vector3d<T>& start, const vector3d<T>& end) : start(start), end(end) {}
29 :
30 : // operators
31 :
32 : line3d<T> operator+(const vector3d<T>& point) const { return line3d<T>(start + point, end + point); }
33 : line3d<T>& operator+=(const vector3d<T>& point) { start += point; end += point; return *this; }
34 :
35 : line3d<T> operator-(const vector3d<T>& point) const { return line3d<T>(start - point, end - point); }
36 : line3d<T>& operator-=(const vector3d<T>& point) { start -= point; end -= point; return *this; }
37 :
38 : bool operator==(const line3d<T>& other) const
39 : { return (start==other.start && end==other.end) || (end==other.start && start==other.end);}
40 : bool operator!=(const line3d<T>& other) const
41 : { return !(start==other.start && end==other.end) || (end==other.start && start==other.end);}
42 :
43 : // functions
44 : //! Set this line to a new line going through the two points.
45 : void setLine(const T& xa, const T& ya, const T& za, const T& xb, const T& yb, const T& zb)
46 : {start.set(xa, ya, za); end.set(xb, yb, zb);}
47 : //! Set this line to a new line going through the two points.
48 : void setLine(const vector3d<T>& nstart, const vector3d<T>& nend)
49 : {start.set(nstart); end.set(nend);}
50 : //! Set this line to new line given as parameter.
51 : void setLine(const line3d<T>& line)
52 : {start.set(line.start); end.set(line.end);}
53 :
54 : //! Get length of line
55 : /** \return Length of line. */
56 1124763 : T getLength() const { return start.getDistanceFrom(end); }
57 :
58 : //! Get squared length of line
59 : /** \return Squared length of line. */
60 : T getLengthSQ() const { return start.getDistanceFromSQ(end); }
61 :
62 : //! Get middle of line
63 : /** \return Center of line. */
64 1124763 : vector3d<T> getMiddle() const
65 : {
66 1124763 : return (start + end)/(T)2;
67 : }
68 :
69 : //! Get vector of line
70 : /** \return vector of line. */
71 1124763 : vector3d<T> getVector() const
72 : {
73 1124763 : return end - start;
74 : }
75 :
76 : //! Check if the given point is between start and end of the line.
77 : /** Assumes that the point is already somewhere on the line.
78 : \param point The point to test.
79 : \return True if point is on the line between start and end, else false.
80 : */
81 : bool isPointBetweenStartAndEnd(const vector3d<T>& point) const
82 : {
83 : return point.isBetweenPoints(start, end);
84 : }
85 :
86 : //! Get the closest point on this line to a point
87 : /** \param point The point to compare to.
88 : \return The nearest point which is part of the line. */
89 : vector3d<T> getClosestPoint(const vector3d<T>& point) const
90 : {
91 : vector3d<T> c = point - start;
92 : vector3d<T> v = end - start;
93 : T d = (T)v.getLength();
94 : v /= d;
95 : T t = v.dotProduct(c);
96 :
97 : if (t < (T)0.0)
98 : return start;
99 : if (t > d)
100 : return end;
101 :
102 : v *= t;
103 : return start + v;
104 : }
105 :
106 : //! Check if the line intersects with a shpere
107 : /** \param sorigin: Origin of the shpere.
108 : \param sradius: Radius of the sphere.
109 : \param outdistance: The distance to the first intersection point.
110 : \return True if there is an intersection.
111 : If there is one, the distance to the first intersection point
112 : is stored in outdistance. */
113 : bool getIntersectionWithSphere(vector3d<T> sorigin, T sradius, f64& outdistance) const
114 : {
115 : const vector3d<T> q = sorigin - start;
116 : T c = q.getLength();
117 : T v = q.dotProduct(getVector().normalize());
118 : T d = sradius * sradius - (c*c - v*v);
119 :
120 : if (d < 0.0)
121 : return false;
122 :
123 : outdistance = v - core::squareroot ( d );
124 : return true;
125 : }
126 :
127 : // member variables
128 :
129 : //! Start point of line
130 : vector3d<T> start;
131 : //! End point of line
132 : vector3d<T> end;
133 : };
134 :
135 : //! Typedef for an f32 line.
136 : typedef line3d<f32> line3df;
137 : //! Typedef for an integer line.
138 : typedef line3d<s32> line3di;
139 :
140 : } // end namespace core
141 : } // end namespace irr
142 :
143 : #endif
144 :
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