implemented shells

shell.cpp

@@ -0,0 +1,39 @@
+#include "shell.h"
+
+#include <solUtil.h>
+
+#include <cmath>
+
+namespace battleship{
+	using namespace std;
+	using namespace vb01;
+	using namespace gameBase;
+
+	Shell::Shell(Unit *un, int id, Vector3 pos, Quaternion rot) : 
+		Projectile(un, id, pos, rot), 
+		initTime(getTime())
+	{
+		initDir = dirVec;
+	}
+
+	void Shell::update(){
+		float currTime = float(getTime() - initTime) / 1000;
+
+		if(currTime == 0) return;
+
+		const float G = generateView()["G"];
+		float angle = initDir.getAngleBetween(Vector3(initDir.x, 0, initDir.z).norm()); 
+
+		dirVec = (
+			pos + 
+			speed * currTime * cos(angle) * Vector3(initDir.x, 0, initDir.z).norm() + 
+			(currTime * speed * sin(angle) - G * currTime * currTime) * Vector3::VEC_J -
+			pos
+		).norm();
+		upVec = Quaternion(-PI / 2, leftVec) * dirVec;
+		model->lookAt(dirVec, upVec);
+
+		Projectile::update();
+		checkCollision();
+	}
+}