void CalculateMovement(float frameTime)
        {
            Vector2 previousPos = Position;

            Velocity.X = MathHelper.Clamp(Velocity.X + horizontalAcceleration * frameTime * movement, -maxHorizontalSpeed, maxHorizontalSpeed);
            if (onGround)
                Velocity.X *= horizontalDragGround;
            else
                Velocity.X *= horizontalDragAir;
            Velocity.Y = MathHelper.Clamp(Velocity.Y + verticalAcceleration * frameTime, -maxVerticalSpeed, maxVerticalSpeed);
            if (onGround)
                Velocity.Y = DoJump();
            DoCollisions();

            if (previousPos.X == Position.X)
                Velocity.X = 0;
            if (previousPos.Y == Position.Y)
                Velocity.Y = 0;
        }

        float DoJump()
        {
            if (World.renderWindow.Input.IsKeyDown(KeyCode.Space))
                return -10;
            else
                return Velocity.Y;
        }

        void DoCollisions()
        {
            onGround = false;
            Position.Y += Velocity.Y;
            Vector2 tileCollision = GetTileCollision();
            if (tileCollision.X != -1 || tileCollision.Y != -1)
            {  
                Vector2 collisionDepth = CollisionRectangle.DepthIntersection(
                    new Rectangle(
                        tileCollision.X * World.tileEngine.TileWidth,
                        tileCollision.Y * World.tileEngine.TileHeight,
                        World.tileEngine.TileWidth,
                        World.tileEngine.TileHeight
                    )
                );
                Position.Y += collisionDepth.Y;
                if (collisionDepth.Y < 0)
                    onGround = true;
            }

            Position.X += Velocity.X;
            tileCollision = GetTileCollision();
            if (tileCollision.X != -1 || tileCollision.Y != -1)
            {
                Vector2 collisionDepth = CollisionRectangle.DepthIntersection(
                    new Rectangle(
                        tileCollision.X * World.tileEngine.TileWidth,
                        tileCollision.Y * World.tileEngine.TileHeight,
                        World.tileEngine.TileWidth,
                        World.tileEngine.TileHeight
                    )
                );
                Position.X += collisionDepth.X;
            }
        }

        Vector2 GetTileCollision()
        {
            int topLeftTileX = (int)(CollisionRectangle.TopLeft.X / World.tileEngine.TileWidth);
            int topLeftTileY = (int)(CollisionRectangle.TopLeft.Y / World.tileEngine.TileHeight);
            int BottomRightTileX = (int)(CollisionRectangle.DownRight.X / World.tileEngine.TileWidth);
            int BottomRightTileY = (int)(CollisionRectangle.DownRight.Y / World.tileEngine.TileHeight);

            if (CollisionRectangle.DownRight.Y % World.tileEngine.TileHeight == 0)
                BottomRightTileY -= 1;
            if (CollisionRectangle.DownRight.X % World.tileEngine.TileWidth == 0)
                BottomRightTileX -= 1;

            for (int i = topLeftTileX; i <= BottomRightTileX; i++)
            {
                for (int j = topLeftTileY; j <= BottomRightTileY; j++)
                {
                    if (World.tileEngine.TileIsSolid(i, j))
                    {
                        return new Vector2(i,j);
                    }
                }
            }

            return new Vector2(-1,-1);
        }