1 /**
  2  Copyright (c) 2010-2012 cocos2d-x.org
  3  Copyright (c) 2008, Luke Benstead.
  4  All rights reserved.
  5 
  6  Redistribution and use in source and binary forms, with or without modification,
  7  are permitted provided that the following conditions are met:
  8 
  9  Redistributions of source code must retain the above copyright notice,
 10  this list of conditions and the following disclaimer.
 11  Redistributions in binary form must reproduce the above copyright notice,
 12  this list of conditions and the following disclaimer in the documentation
 13  and/or other materials provided with the distribution.
 14 
 15  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND
 16  ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 17  WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 18  DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
 19  ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 20  (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 21  LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
 22  ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 23  (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 24  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 25  */
 26 
 27 /**
 28  * @ignore
 29  */
 30 cc.KM_PLANE_LEFT = 0;
 31 
 32 cc.KM_PLANE_RIGHT = 1;
 33 
 34 cc.KM_PLANE_BOTTOM = 2;
 35 
 36 cc.KM_PLANE_TOP = 3;
 37 
 38 cc.KM_PLANE_NEAR = 4;
 39 
 40 cc.KM_PLANE_FAR = 5;
 41 
 42 cc.kmPlane = function (a, b, c, d) {
 43     this.a = a || 0;
 44     this.b = b || 0;
 45     this.c = c || 0;
 46     this.d = d || 0;
 47 };
 48 
 49 cc.POINT_INFRONT_OF_PLANE = 0;
 50 
 51 cc.POINT_BEHIND_PLANE = 1;
 52 
 53 cc.POINT_ON_PLANE = 2;
 54 
 55 cc.kmPlaneDot = function(pP, pV){
 56     //a*x + b*y + c*z + d*w
 57     return (pP.a * pV.x +
 58         pP.b * pV.y +
 59         pP.c * pV.z +
 60         pP.d * pV.w);
 61 };
 62 
 63 cc.kmPlaneDotCoord = function(pP, pV){
 64     return (pP.a * pV.x +
 65         pP.b * pV.y +
 66         pP.c * pV.z + pP.d);
 67 };
 68 
 69 cc.kmPlaneDotNormal = function(pP, pV){
 70     return (pP.a * pV.x +
 71         pP.b * pV.y +
 72         pP.c * pV.z);
 73 };
 74 
 75 cc.kmPlaneFromPointNormal = function(pOut, pPoint, pNormal){
 76     /*
 77      Planea = Nx
 78      Planeb = Ny
 79      Planec = Nz
 80      Planed = −N⋅P
 81      */
 82     pOut.a = pNormal.x;
 83     pOut.b = pNormal.y;
 84     pOut.c = pNormal.z;
 85     pOut.d = -cc.kmVec3Dot(pNormal, pPoint);
 86 
 87     return pOut;
 88 };
 89 
 90 /**
 91  * Creates a plane from 3 points. The result is stored in pOut.
 92  * pOut is returned.
 93  */
 94 cc.kmPlaneFromPoints = function(pOut, p1, p2, p3){
 95     /*
 96      v = (B − A) × (C − A)
 97      n = 1⁄|v| v
 98      Outa = nx
 99      Outb = ny
100      Outc = nz
101      Outd = −n⋅A
102      */
103 
104     var n = new cc.kmVec3(), v1 = new cc.kmVec3(), v2 = new cc.kmVec3();
105     cc.kmVec3Subtract(v1, p2, p1); //Create the vectors for the 2 sides of the triangle
106     cc.kmVec3Subtract(v2, p3, p1);
107     cc.kmVec3Cross(n, v1, v2); //Use the cross product to get the normal
108 
109     cc.kmVec3Normalize(n, n); //Normalize it and assign to pOut.m_N
110 
111     pOut.a = n.x;
112     pOut.b = n.y;
113     pOut.c = n.z;
114     pOut.d = cc.kmVec3Dot(cc.kmVec3Scale(n, n, -1.0), p1);
115 
116     return pOut;
117 };
118 
119 cc.kmPlaneIntersectLine = function(pOut, pP, pV1, pV2){
120     throw "cc.kmPlaneIntersectLine() hasn't been implemented.";
121     /*
122      n = (Planea, Planeb, Planec)
123      d = V − U
124      Out = U − d⋅(Pd + n⋅U)⁄(d⋅n) [iff d⋅n ≠ 0]
125      */
126     //var d = new cc.kmVec3();
127 
128     //cc.kmVec3Subtract(d, pV2, pV1); //Get the direction vector
129 
130     //TODO: Continue here!
131     /*if (fabs(kmVec3Dot(&pP.m_N, &d)) > kmEpsilon)
132      {
133      //If we get here then the plane and line are parallel (i.e. no intersection)
134      pOut = nullptr; //Set to nullptr
135 
136      return pOut;
137      } */
138 
139     //return null;
140 };
141 
142 cc.kmPlaneNormalize = function(pOut, pP){
143     var n = new cc.kmVec3();
144 
145     n.x = pP.a;
146     n.y = pP.b;
147     n.z = pP.c;
148 
149     var l = 1.0 / cc.kmVec3Length(n); //Get 1/length
150     cc.kmVec3Normalize(n, n); //Normalize the vector and assign to pOut
151 
152     pOut.a = n.x;
153     pOut.b = n.y;
154     pOut.c = n.z;
155 
156     pOut.d = pP.d * l; //Scale the D value and assign to pOut
157 
158     return pOut;
159 };
160 
161 cc.kmPlaneScale = function(pOut, pP, s){
162     cc.log("cc.kmPlaneScale() has not been implemented.");
163 };
164 
165 /**
166  * Returns POINT_INFRONT_OF_PLANE if pP is infront of pIn. Returns
167  * POINT_BEHIND_PLANE if it is behind. Returns POINT_ON_PLANE otherwise
168  */
169 cc.kmPlaneClassifyPoint = function(pIn, pP){
170     // This function will determine if a point is on, in front of, or behind
171     // the plane.  First we store the dot product of the plane and the point.
172     var distance = pIn.a * pP.x + pIn.b * pP.y + pIn.c * pP.z + pIn.d;
173 
174     // Simply put if the dot product is greater than 0 then it is infront of it.
175     // If it is less than 0 then it is behind it.  And if it is 0 then it is on it.
176     if(distance > 0.001) return cc.POINT_INFRONT_OF_PLANE;
177     if(distance < -0.001) return cc.POINT_BEHIND_PLANE;
178 
179     return cc.POINT_ON_PLANE;
180 };
181 
182 
183