Calc based on tool center

With the "calculation based on tool center" disabled the touching points (yellow dots) of tool and drive surface are on the same level.

$source\calc_based_on_tool_center_dialog_off.jpg$

$source\calc_based_on_tool_center.jpg$

With "calculation based on tool center" the tool center (red dots) is on the same level

$source\calc_based_on_tool_center_on.jpg$

$source\calc_based_on_tool_center_1.jpg$