Terraria.Player.BordersMovement C# (CSharp) Method

        public void BordersMovement()
        {
            if ((double)this.position.X < (double)Main.leftWorld + 640.0 + 16.0)
            {
                this.position.X = (float)((double)Main.leftWorld + 640.0 + 16.0);
                this.velocity.X = 0.0f;
            }
            if ((double)this.position.X + (double)this.width > (double)Main.rightWorld - 640.0 - 32.0)
            {
                this.position.X = (float)((double)Main.rightWorld - 640.0 - 32.0) - (float)this.width;
                this.velocity.X = 0.0f;
            }
            if ((double)this.position.Y < (double)Main.topWorld + 640.0 + 16.0)
            {
                this.position.Y = (float)((double)Main.topWorld + 640.0 + 16.0);
                if ((double)this.velocity.Y < 0.11)
                    this.velocity.Y = 0.11f;
                this.gravDir = 1f;
                AchievementsHelper.HandleSpecialEvent(this, 11);
            }
            if ((double)this.position.Y > (double)Main.bottomWorld - 640.0 - 32.0 - (double)this.height)
            {
                this.position.Y = (float)((double)Main.bottomWorld - 640.0 - 32.0) - (float)this.height;
                this.velocity.Y = 0.0f;
            }
            if ((double)this.position.Y <= (double)Main.bottomWorld - 640.0 - 150.0 - (double)this.height)
                return;
            AchievementsHelper.HandleSpecialEvent(this, 10);
        }