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graphic-o3d-samples-box2d-3d-third-party-box2d-collision-shapes-b2CircleShape.js / js



  /*
  * Copyright (c) 2006-2007 Erin Catto 
* This software is provided 'as-is', without any express or implied
* warranty.  In no event will the authors be held liable for any damages
* arising from the use of this software.
* Permission is granted to anyone to use this software for any purpose,
* including commercial applications, and to alter it and redistribute it
* freely, subject to the following restrictions:
* 1. The origin of this software must not be misrepresented; you must not
* claim that you wrote the original software. If you use this software
* in a product, an acknowledgment in the product documentation would be
* appreciated but is not required.
* 2. Altered source versions must be plainly marked, and must not be
* misrepresented the original software.
* 3. This notice may not be removed or altered from any source distribution.
*/

var b2CircleShape = Class.create();
Object.extend(b2CircleShape.prototype, b2Shape.prototype);
Object.extend(b2CircleShape.prototype, 
{
        TestPoint: function(p){
                //var d = b2Math.SubtractVV(p, this.m_position);
                var d = new b2Vec2();
                d.SetV(p);
                d.Subtract(this.m_position);
                return b2Math.b2Dot(d, d) <= this.m_radius * this.m_radius;
        },

        //--------------- Internals Below -------------------

        initialize: function(def, body, localCenter){
                // initialize instance variables for references
                this.m_R = new b2Mat22();
                this.m_position = new b2Vec2();
                //

                // The constructor for b2Shape
                this.m_userData = def.userData;

                this.m_friction = def.friction;
                this.m_restitution = def.restitution;
                this.m_body = body;

                this.m_proxyId = b2Pair.b2_nullProxy;

                this.m_maxRadius = 0.0;

                this.m_categoryBits = def.categoryBits;
                this.m_maskBits = def.maskBits;
                this.m_groupIndex = def.groupIndex;
                //

                // initialize instance variables for references
                this.m_localPosition = new b2Vec2();
                //

                //super(def, body);

                //b2Settings.b2Assert(def.type == b2Shape.e_circleShape);
                var circle = def;

                //this.m_localPosition = def.localPosition - localCenter;
                this.m_localPosition.Set(def.localPosition.x - localCenter.x, def.localPosition.y - localCenter.y);
                this.m_type = b2Shape.e_circleShape;
                this.m_radius = circle.radius;

                this.m_R.SetM(this.m_body.m_R);
                //b2Vec2 r = b2Mul(this.m_body->this.m_R, this.m_localPosition);
                var rX = this.m_R.col1.x * this.m_localPosition.x + this.m_R.col2.x * this.m_localPosition.y;
                var rY = this.m_R.col1.y * this.m_localPosition.x + this.m_R.col2.y * this.m_localPosition.y;
                //this.m_position = this.m_body->this.m_position + r;
                this.m_position.x = this.m_body.m_position.x + rX;
                this.m_position.y = this.m_body.m_position.y + rY;
                //this.m_maxRadius = r.Length() + this.m_radius;
                this.m_maxRadius = Math.sqrt(rX*rX+rY*rY) + this.m_radius;

                var aabb = new b2AABB();
                aabb.minVertex.Set(this.m_position.x - this.m_radius, this.m_position.y - this.m_radius);
                aabb.maxVertex.Set(this.m_position.x + this.m_radius, this.m_position.y + this.m_radius);

                var broadPhase = this.m_body.m_world.m_broadPhase;
                if (broadPhase.InRange(aabb))
                {
                        this.m_proxyId = broadPhase.CreateProxy(aabb, this);
                }
                else
                {
                        this.m_proxyId = b2Pair.b2_nullProxy;
                }

                if (this.m_proxyId == b2Pair.b2_nullProxy)
                {
                        this.m_body.Freeze();
                }
        },

        Synchronize: function(position1, R1, position2, R2){
                this.m_R.SetM(R2);
                //this.m_position = position2 + b2Mul(R2, this.m_localPosition);
                this.m_position.x = (R2.col1.x * this.m_localPosition.x + R2.col2.x * this.m_localPosition.y) + position2.x;
                this.m_position.y = (R2.col1.y * this.m_localPosition.x + R2.col2.y * this.m_localPosition.y) + position2.y;

                if (this.m_proxyId == b2Pair.b2_nullProxy)
                {
                        return;
                }

                // Compute an AABB that covers the swept shape (may miss some rotation effect).
                //b2Vec2 p1 = position1 + b2Mul(R1, this.m_localPosition);
                var p1X = position1.x + (R1.col1.x * this.m_localPosition.x + R1.col2.x * this.m_localPosition.y);
                var p1Y = position1.y + (R1.col1.y * this.m_localPosition.x + R1.col2.y * this.m_localPosition.y);
                //b2Vec2 lower = b2Min(p1, this.m_position);
                var lowerX = Math.min(p1X, this.m_position.x);
                var lowerY = Math.min(p1Y, this.m_position.y);
                //b2Vec2 upper = b2Max(p1, this.m_position);
                var upperX = Math.max(p1X, this.m_position.x);
                var upperY = Math.max(p1Y, this.m_position.y);

                var aabb = new b2AABB();
                aabb.minVertex.Set(lowerX - this.m_radius, lowerY - this.m_radius);
                aabb.maxVertex.Set(upperX + this.m_radius, upperY + this.m_radius);

                var broadPhase = this.m_body.m_world.m_broadPhase;
                if (broadPhase.InRange(aabb))
                {
                        broadPhase.MoveProxy(this.m_proxyId, aabb);
                }
                else
                {
                        this.m_body.Freeze();
                }
        },

        QuickSync: function(position, R){
                this.m_R.SetM(R);
                //this.m_position = position + b2Mul(R, this.m_localPosition);
                this.m_position.x = (R.col1.x * this.m_localPosition.x + R.col2.x * this.m_localPosition.y) + position.x;
                this.m_position.y = (R.col1.y * this.m_localPosition.x + R.col2.y * this.m_localPosition.y) + position.y;
        },

        ResetProxy: function(broadPhase)
        {
                if (this.m_proxyId == b2Pair.b2_nullProxy)
                {
                        return;
                }

                var proxy = broadPhase.GetProxy(this.m_proxyId);

                broadPhase.DestroyProxy(this.m_proxyId);
                proxy = null;

                var aabb = new b2AABB();
                aabb.minVertex.Set(this.m_position.x - this.m_radius, this.m_position.y - this.m_radius);
                aabb.maxVertex.Set(this.m_position.x + this.m_radius, this.m_position.y + this.m_radius);

                if (broadPhase.InRange(aabb))
                {
                        this.m_proxyId = broadPhase.CreateProxy(aabb, this);
                }
                else
                {
                        this.m_proxyId = b2Pair.b2_nullProxy;
                }

                if (this.m_proxyId == b2Pair.b2_nullProxy)
                {
                        this.m_body.Freeze();
                }
        },

        Support: function(dX, dY, out)
        {
                //b2Vec2 u = d;
                //u.Normalize();
                var len = Math.sqrt(dX*dX + dY*dY);
                dX /= len;
                dY /= len;
                //return this.m_position + this.m_radius * u;
                out.Set(        this.m_position.x + this.m_radius*
  *
  * This software is provided 'as-is', without any express or implied
  * warranty.  In no event will the authors be held liable for any damages
  * arising from the use of this software.
  * Permission is granted to anyone to use this software for any purpose,
  * including commercial applications, and to alter it and redistribute it
  * freely, subject to the following restrictions:
  * 1. The origin of this software must not be misrepresented; you must not
  * claim that you wrote the original software. If you use this software
  * in a product, an acknowledgment in the product documentation would be
  * appreciated but is not required.
  * 2. Altered source versions must be plainly marked, and must not be
  * misrepresented the original software.
  * 3. This notice may not be removed or altered from any source distribution.
  */
  
  var b2CircleShape = Class.create();
  Object.extend(b2CircleShape.prototype, b2Shape.prototype);
  Object.extend(b2CircleShape.prototype, 
  {
          TestPoint: function(p){
                  //var d = b2Math.SubtractVV(p, this.m_position);
                  var d = new b2Vec2();
                  d.SetV(p);
                  d.Subtract(this.m_position);
                  return b2Math.b2Dot(d, d) <= this.m_radius * this.m_radius;
          },
  
          //--------------- Internals Below -------------------
  
          initialize: function(def, body, localCenter){
                  // initialize instance variables for references
                  this.m_R = new b2Mat22();
                  this.m_position = new b2Vec2();
                  //
  
                  // The constructor for b2Shape
                  this.m_userData = def.userData;
  
                  this.m_friction = def.friction;
                  this.m_restitution = def.restitution;
                  this.m_body = body;
  
                  this.m_proxyId = b2Pair.b2_nullProxy;
  
                  this.m_maxRadius = 0.0;
  
                  this.m_categoryBits = def.categoryBits;
                  this.m_maskBits = def.maskBits;
                  this.m_groupIndex = def.groupIndex;
                  //
  
                  // initialize instance variables for references
                  this.m_localPosition = new b2Vec2();
                  //
  
                  //super(def, body);
  
                  //b2Settings.b2Assert(def.type == b2Shape.e_circleShape);
                  var circle = def;
  
                  //this.m_localPosition = def.localPosition - localCenter;
                  this.m_localPosition.Set(def.localPosition.x - localCenter.x, def.localPosition.y - localCenter.y);
                  this.m_type = b2Shape.e_circleShape;
                  this.m_radius = circle.radius;
  
                  this.m_R.SetM(this.m_body.m_R);
                  //b2Vec2 r = b2Mul(this.m_body->this.m_R, this.m_localPosition);
                  var rX = this.m_R.col1.x * this.m_localPosition.x + this.m_R.col2.x * this.m_localPosition.y;
                  var rY = this.m_R.col1.y * this.m_localPosition.x + this.m_R.col2.y * this.m_localPosition.y;
                  //this.m_position = this.m_body->this.m_position + r;
                  this.m_position.x = this.m_body.m_position.x + rX;
                  this.m_position.y = this.m_body.m_position.y + rY;
                  //this.m_maxRadius = r.Length() + this.m_radius;
                  this.m_maxRadius = Math.sqrt(rX*rX+rY*rY) + this.m_radius;
  
                  var aabb = new b2AABB();
                  aabb.minVertex.Set(this.m_position.x - this.m_radius, this.m_position.y - this.m_radius);
                  aabb.maxVertex.Set(this.m_position.x + this.m_radius, this.m_position.y + this.m_radius);
  
                  var broadPhase = this.m_body.m_world.m_broadPhase;
                  if (broadPhase.InRange(aabb))
                  {
                          this.m_proxyId = broadPhase.CreateProxy(aabb, this);
                  }
                  else
                  {
                          this.m_proxyId = b2Pair.b2_nullProxy;
                  }
  
                  if (this.m_proxyId == b2Pair.b2_nullProxy)
                  {
                          this.m_body.Freeze();
                  }
          },
  
          Synchronize: function(position1, R1, position2, R2){
                  this.m_R.SetM(R2);
                  //this.m_position = position2 + b2Mul(R2, this.m_localPosition);
                  this.m_position.x = (R2.col1.x * this.m_localPosition.x + R2.col2.x * this.m_localPosition.y) + position2.x;
                  this.m_position.y = (R2.col1.y * this.m_localPosition.x + R2.col2.y * this.m_localPosition.y) + position2.y;
  
                  if (this.m_proxyId == b2Pair.b2_nullProxy)
                  {
                          return;
                  }
  
                  // Compute an AABB that covers the swept shape (may miss some rotation effect).
                  //b2Vec2 p1 = position1 + b2Mul(R1, this.m_localPosition);
                  var p1X = position1.x + (R1.col1.x * this.m_localPosition.x + R1.col2.x * this.m_localPosition.y);
                  var p1Y = position1.y + (R1.col1.y * this.m_localPosition.x + R1.col2.y * this.m_localPosition.y);
                  //b2Vec2 lower = b2Min(p1, this.m_position);
                  var lowerX = Math.min(p1X, this.m_position.x);
                  var lowerY = Math.min(p1Y, this.m_position.y);
                  //b2Vec2 upper = b2Max(p1, this.m_position);
                  var upperX = Math.max(p1X, this.m_position.x);
                  var upperY = Math.max(p1Y, this.m_position.y);
  
                  var aabb = new b2AABB();
                  aabb.minVertex.Set(lowerX - this.m_radius, lowerY - this.m_radius);
                  aabb.maxVertex.Set(upperX + this.m_radius, upperY + this.m_radius);
  
                  var broadPhase = this.m_body.m_world.m_broadPhase;
                  if (broadPhase.InRange(aabb))
                  {
                          broadPhase.MoveProxy(this.m_proxyId, aabb);
                  }
                  else
                  {
                          this.m_body.Freeze();
                  }
          },
  
          QuickSync: function(position, R){
                  this.m_R.SetM(R);
                  //this.m_position = position + b2Mul(R, this.m_localPosition);
                  this.m_position.x = (R.col1.x * this.m_localPosition.x + R.col2.x * this.m_localPosition.y) + position.x;
                  this.m_position.y = (R.col1.y * this.m_localPosition.x + R.col2.y * this.m_localPosition.y) + position.y;
          },
  
          ResetProxy: function(broadPhase)
          {
                  if (this.m_proxyId == b2Pair.b2_nullProxy)
                  {
                          return;
                  }
  
                  var proxy = broadPhase.GetProxy(this.m_proxyId);
  
                  broadPhase.DestroyProxy(this.m_proxyId);
                  proxy = null;
  
                  var aabb = new b2AABB();
                  aabb.minVertex.Set(this.m_position.x - this.m_radius, this.m_position.y - this.m_radius);
                  aabb.maxVertex.Set(this.m_position.x + this.m_radius, this.m_position.y + this.m_radius);
  
                  if (broadPhase.InRange(aabb))
                  {
                          this.m_proxyId = broadPhase.CreateProxy(aabb, this);
                  }
                  else
                  {
                          this.m_proxyId = b2Pair.b2_nullProxy;
                  }
  
                  if (this.m_proxyId == b2Pair.b2_nullProxy)
                  {
                          this.m_body.Freeze();
                  }
          },
  
          Support: function(dX, dY, out)
          {
                  //b2Vec2 u = d;
                  //u.Normalize();
                  var len = Math.sqrt(dX*dX + dY*dY);
                  dX /= len;
                  dY /= len;
                  //return this.m_position + this.m_radius * u;
                  out.Set(        this.m_position.x + this.m_radius*dX,
                                          this.m_position.y + this.m_radius*dY);
          },
  
          // Local position in parent body
          m_localPosition: new b2Vec2(),
          m_radius: null});
  
  


(C) Æliens 20/2/2008

You may not copy or print any of this material without explicit permission of the author or the publisher. In case of other copyright issues, contact the author.