Initial commit.

physics/translation.h

@@ -0,0 +1,70 @@
+// -*- C++ -*-
+
+#ifndef MBOSTOCK_TRANSLATION_H
+#define MBOSTOCK_TRANSLATION_H
+
+#include "shape.h"
+#include "transform.h"
+#include "vector.h"
+
+namespace mbostock {
+
+  class Translation : public Transform {
+  public:
+    Translation(const Vector& x0, const Vector& x1,
+                float s, float u, float kd);
+
+    enum Mode { REVERSE, RESET, ONE_WAY };
+
+    /* Sets the translation mode. The default is REVERSE. */
+    void setMode(Mode m);
+
+    /** Translates the specified point. */
+    Vector point(const Vector& x) const;
+
+    /** Inverse-translates the specified point. */
+    Vector pointInverse(const Vector& x) const;
+
+    /** Advances the translation by one time step. */
+    virtual void step();
+
+    /** Resets the translation. */
+    virtual void reset();
+
+    /** Returns the current velocity. */
+    const Vector& velocity() const;
+
+    /** Returns the current origin. */
+    inline const Vector& origin() const { return origin_; }
+
+  private:
+    void update();
+
+    Vector x0_;
+    Vector x1_;
+    float s_;
+    float u_;
+    float kd_;
+    Vector v_;
+    Vector dv_;
+    Vector x_;
+    Vector origin_;
+    Mode mode_;
+    bool reversed_;
+  };
+
+  class TranslatingShape : public Shape {
+  public:
+    TranslatingShape(const Shape& s, const Translation& t);
+
+    virtual bool intersects(const Sphere& s) const;
+    virtual Projection project(const Vector& x) const;
+
+  private:
+    const Shape& shape_;
+    const Translation& translation_;
+  };
+
+}
+
+#endif