Initial bullet physics support

1 files changed, 166 insertions, 0 deletions

diff --git a/src/game/base/physics.h b/src/game/base/physics.h
new file mode 100644
index 0000000..37ed1cf
--- /dev/null
+++ b/src/game/base/physics.h
@@ -0,0 +1,166 @@
+/*
+   base/physics.h
+   This file is part of the Osirion project and is distributed under 
+   the terms and conditions of the GNU General Public License version 2 
+*/
+
+#ifndef __INCLUDED_BASE_PHYSICS_H__
+#define __INCLUDED_BASE_PHYSICS_H__
+
+#include "sys/sys.h"
+#include "core/zone.h"
+#include <vector>
+
+#ifdef HAVE_BULLET
+#include "btBulletDynamicsCommon.h"
+#include "BulletCollision/CollisionShapes/btTriangleMesh.h"
+#endif
+
+/*
+
+	This file provides the interface between the osirion game library
+	and the bullet physics library
+
+*/
+
+namespace game {
+
+#ifdef HAVE_BULLET
+/// helper function to convert math:Vector3f to btVector3
+inline btVector3 to_btVector3(const math::Vector3f & v)
+{
+	return btVector3(v[0], v[1], v[2]);
+}
+
+/// helper function to conver math::Axis to btMatrix3x3
+inline btMatrix3x3 to_btMatrix3x3(const math::Axis &a)
+{
+	return btMatrix3x3(a[0][0], a[0][1], a[0][2],
+			a[1][0], a[1][1], a[1][2],
+			a[2][0], a[2][1], a[2][2]);
+};
+#endif
+
+/* ---- class CollisionShape --------------------------------------- */
+
+/// a bullet collision shape
+class CollisionShape {
+public:
+	CollisionShape(model::Model *model, const bool moving);
+
+	~CollisionShape();
+
+	inline const std::string &label() const { return shape_label; }
+
+	inline const bool moving() const { return shape_moving; }
+
+#ifdef HAVE_BULLET
+	inline btCollisionShape *bullet_shape() { return shape_bulletshape; }
+#endif
+
+/* ----- static functions for the shape registry ------------------- */
+
+	/// tpye definition for the collision shape registry
+	typedef std::vector<CollisionShape *> Registry;
+
+	static void clear();
+
+	static CollisionShape *add(model::Model *model, const bool moving);
+
+	static CollisionShape *find(model::Model *model, const bool moving);
+
+private:
+	std::string shape_label;
+	bool shape_moving;
+
+#ifdef HAVE_BULLET
+	btCollisionShape *shape_bulletshape;
+	btTriangleMesh *shape_mesh;
+#endif
+
+	/// collision shape registry
+	static Registry shape_registry;
+};
+
+/* ---- class Physics ---------------------------------------------- */
+
+/// main physics functions
+class Physics {
+public:
+	/// intialize world physics
+	static void init();
+
+	/// run a world physics frame
+	static void frame(const float elapsed);
+
+	/// shutdown world physics
+	static void shutdown();
+
+#ifdef HAVE_BULLET
+	static btDefaultCollisionConfiguration *configuration;
+
+	static btCollisionDispatcher *dispatcher;
+
+	static btSequentialImpulseConstraintSolver *solver;
+#endif
+};
+
+/* ---- class PhysicsZone ------------------------------------------ */
+
+/// a zone containing collision objects
+class PhysicsZone : public core::Zone {
+public:
+	PhysicsZone(const std::string &label);
+	virtual ~PhysicsZone();
+
+#ifdef HAVE_BULLET
+	inline  btDiscreteDynamicsWorld *dynamics_world() { return zone_dynamics_world; }
+
+private:
+	btAxisSweep3			*zone_cache;
+	btDiscreteDynamicsWorld 	*zone_dynamics_world;
+#endif
+};
+
+/* ---- class PhysicsBody ------------------------------------------ */
+
+/// an object that is capable of colliding with other objects
+class PhysicsBody {
+public:
+	/// initialize a collider attached to an entity
+	/** 
+	 * a PhysicsBody with zero mass is considered non-moving
+	 */
+	PhysicsBody(core::Entity *entity);
+	~PhysicsBody();
+
+	/// initialize the collision body
+	void init_physics(const float mass);
+
+	/// shutdown the collision body
+	void shutdown_physics();
+
+	/// collider mass
+	inline const float mass() const { return collider_mass; }
+
+	/// the entity the collider is attached to
+	inline core::Entity *entity() { return collider_entity; }
+
+#ifdef HAVE_BULLET
+	/// the bullet rigid body associated with this collider
+	inline btRigidBody *body() { return collider_body; }
+#endif
+
+private:
+	CollisionShape	*collider_shape;
+	core::Entity	*collider_entity;
+#ifdef HAVE_BULLET
+	btRigidBody 	*collider_body;
+#endif
+	float		collider_mass;
+};
+
+}
+
+#endif // __INCLUDED_BASE_PHYSICS_H__
+