Reorganize source files into logical subdirectories

Co-authored-by: Hirek193 <23196899+Hirek193@users.noreply.github.com>

world/Spring.h

@@ -0,0 +1,42 @@
+/*
+This Source Code Form is subject to the
+terms of the Mozilla Public License, v.
+2.0. If a copy of the MPL was not
+distributed with this file, You can
+obtain one at
+http://mozilla.org/MPL/2.0/.
+*/
+
+#ifndef ParticlesH
+#define ParticlesH
+
+#include "dumb3d.h"
+/*
+#define STATIC_THRESHOLD 0.17f
+const double m_Kd = 0.02f; // DAMPING FACTOR
+const double m_Kr = 0.8f; // 1.0 = SUPERBALL BOUNCE 0.0 = DEAD WEIGHT
+const double m_Ksh = 5.0f; // HOOK'S SPRING CONSTANT
+const double m_Ksd = 0.1f; // SPRING DAMPING CONSTANT
+
+const double m_Csf = 0.9f; // Default Static Friction
+const double m_Ckf = 0.7f; // Default Kinetic Friction
+*/
+class TSpring {
+
+public:
+    TSpring() = default;
+    //    void Init(TParticnp1, TParticle *np2, double nKs= 0.5f, double nKd= 0.002f,
+    //    double nrestLen= -1.0f);
+    void Init(double nKs = 0.5f, double nKd = 0.002f);
+    Math3D::vector3 ComputateForces( Math3D::vector3 const &pPosition1, Math3D::vector3 const &pPosition2);
+//private:
+// members
+    double restLen { 0.01 }; // LENGTH OF SPRING AT REST
+    double Ks { 0.0 }; // SPRING CONSTANT
+    double Kd { 0.0 }; // SPRING DAMPING
+    float ks{ 0.f };
+    float kd{ 0.f };
+};
+
+//---------------------------------------------------------------------------
+#endif