ZScript - Viewport 2D target projection error

    void DrawMainBar (double TicFrac)
    {
        if(CPlayer && CPlayer.mo)
        {
            let mech = MechWarrior(CPlayer.mo);
            if(!mech)return;

            if(mech.targetenemy && mech.targetenemy.health > 0)
            {
                Actor target = mech.targetenemy;

                vector2 screencoords;
                vector3 fromworldpos;
                vector3 eyepos = (mech.pos.x, mech.pos.y, mech.pos.z);

                double distance = mech.Distance3D(target);
                float viewfov = mech.player.FOV;

                bool behind;

                console.printf("%f",mech.pitch);

                fromworldpos = MWD_CoordUtil.WorldToScreen(target.pos,eyepos,mech.pitch,mech.angle,mech.roll,viewfov);
                [screencoords, behind] = MWD_CoordUtil.toViewport(fromworldpos);

                if (-1 < fromworldpos.z && fromworldpos.z <= 1)
                {
                      // this is the coordinates where you're drawing to:
                      if (distance == 0) { return; }

                      double  height        = target.height;
                      double  radius        = target.radius;
                      double  visibleRadius = radius * 2000.0 / distance;
                      double  visibleHeight = height * 1000.0 / distance;

                      Vector2 left   = (screencoords.x - visibleRadius / 2.0, screencoords.y);
                      Vector2 right  = (screencoords.x + visibleRadius / 2.0, screencoords.y);
                      Vector2 top    = (screencoords.x, screencoords.y - visibleHeight / 2.0);
                      Vector2 bottom = (screencoords.x, screencoords.y + visibleHeight / 2.0);

                      Vector2 topLeft     = (left.x,  top.y);
                      Vector2 topRight    = (right.x, top.y);
                      Vector2 bottomLeft  = (left.x,  bottom.y);
                      Vector2 bottomRight = (right.x, bottom.y);

                      DrawImage("RETCA0",topLeft,0,1.0);
                      DrawImage("RETCB0",topRight,0,1.0);
                      DrawImage("RETCC0",bottomLeft,0,1.0);
                      DrawImage("RETCD0",bottomRight,0,1.0);
                 }