Dogcows Code - chaz/yoink/blob - src/Moof/Sphere.hh

   1
   2 /*******************************************************************************
   3
   4  Copyright (c) 2009, Charles McGarvey
   5  All rights reserved.
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   7  Redistribution   and   use  in  source  and  binary  forms,  with  or  without
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  10    * Redistributions  of  source  code  must retain the above copyright notice,
  11      this list of conditions and the following disclaimer.
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  13      this  list of conditions and the following disclaimer in the documentation
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  16  THIS  SOFTWARE  IS  PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  17  AND  ANY  EXPRESS  OR  IMPLIED  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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  27 *******************************************************************************/
  28
  29 #ifndef _MOOF_SPHERE_HH_
  30 #define _MOOF_SPHERE_HH_
  31
  32 #include <Moof/Cullable.hh>
  33 #include <Moof/Drawable.hh>
  34 #include <Moof/Frustum.hh>
  35 #include <Moof/Math.hh>
  36 #include <Moof/OpenGL.hh>
  37 #include <Moof/Shape.hh>
  38
  39
  40 namespace Mf {
  41
  42
  43 /**
  44  * A round object.
  45  */
  46
  47 template <int D = 3>
  48 struct Sphere : public Cullable, public Drawable, public Shape<D>
  49 {
  50         typedef cml::vector< Scalar, cml::fixed<D> >    Vector;
  51
  52         // (solution - point)^2 - radius^2 = 0
  53         Vector  point;
  54         Scalar  radius;
  55
  56         Sphere() {}
  57
  58         Sphere(const Vector& p, Scalar r) :
  59                 point(p),
  60                 radius(r) {}
  61
  62         //Sphere(Scalar x, Scalar y, Scalar z, Scalar r) :
  63                 //point(x, y, z),
  64                 //radius(r) {}
  65
  66         void init(const Vector& p, Scalar r)
  67         {
  68                 point = p;
  69                 radius = r;
  70         }
  71
  72         void init(const Vector& p, const Vector& o)
  73         {
  74                 point = p;
  75                 radius = (o - p).length();
  76         }
  77
  78
  79         // a ray inside the sphere will not intersect on its way out
  80         Scalar intersectRay(const Ray<D>& ray,
  81                         typename Ray<D>::Intersection& intersection)
  82         {
  83                 Vector b = point - ray.point;
  84                 Scalar z = cml::dot(b, ray.direction);
  85
  86                 // check if the ball is behind the ray
  87                 if (z < SCALAR(0.0)) return SCALAR(-1.0);
  88
  89                 Scalar d2 = cml::dot(b, b) - z*z;
  90                 Scalar r2 = radius * radius;
  91
  92                 // check for an intersection
  93                 if (d2 > r2) return SCALAR(-1.0);
  94
  95                 Scalar t = z - std::sqrt(r2 - d2);
  96                 ray.solve(intersection.point, t);
  97                 intersection.normal = intersection.point - point;
  98
  99                 return t;
 100         }
 101
 102
 103         //void encloseVertices(const Vector vertices[], unsigned count);
 104
 105         //void draw(Scalar alpha = 0.0) const;
 106         //bool isVisible(const Frustum& frustum) const;
 107
 108 void encloseVertices(const Vector vertices[], unsigned count)
 109 {
 110         // TODO
 111 }
 112
 113 void draw(Scalar alpha = 0.0) const;
 114 //{
 115         //GLUquadricObj* sphereObj = gluNewQuadric();
 116         //gluQuadricDrawStyle(sphereObj, GLU_LINE);
 117
 118         //glPushMatrix();
 119
 120         //glTranslate(point);
 121         //gluSphere(sphereObj, GLdouble(radius), 16, 16);
 122
 123         //glPopMatrix();
 124
 125         //gluDeleteQuadric(sphereObj);
 126 //}
 127
 128 bool isVisible(const Frustum& frustum) const
 129 {
 130         return true;
 131 }
 132 };
 133
 134
 135 template <>
 136 inline bool Sphere<3>::isVisible(const Frustum& frustum) const
 137 {
 138         return frustum.contains(*this);
 139 }
 140
 141 template <>
 142 inline void Sphere<2>::draw(Scalar alpha) const
 143 {
 144         GLUquadricObj* sphereObj = gluNewQuadric();
 145         gluQuadricDrawStyle(sphereObj, GLU_LINE);
 146
 147         glPushMatrix();
 148
 149         glTranslate(promote(point));
 150         gluSphere(sphereObj, GLdouble(radius), 16, 16);
 151
 152         glPopMatrix();
 153
 154         gluDeleteQuadric(sphereObj);
 155 }
 156
 157 template <>
 158 inline void Sphere<3>::draw(Scalar alpha) const
 159 {
 160         GLUquadricObj* sphereObj = gluNewQuadric();
 161         gluQuadricDrawStyle(sphereObj, GLU_LINE);
 162
 163         glPushMatrix();
 164
 165         glTranslate(point);
 166         gluSphere(sphereObj, GLdouble(radius), 16, 16);
 167
 168         glPopMatrix();
 169
 170         gluDeleteQuadric(sphereObj);
 171 }
 172
 173 template <int D>
 174 inline bool checkCollision(const Sphere<D>& a, const Sphere<D>& b)
 175 {
 176         Scalar d = (a.point - b.point).length();
 177         return d < (a.radius + b.radius);
 178 }
 179
 180
 181 } // namespace Mf
 182
 183 #endif // _MOOF_SPHERE_HH_
 184
 185 /** vim: set ts=4 sw=4 tw=80: *************************************************/
 186