A Novel Algorithm for CAD to CSG Conversion in McCAD^†

Round 1

Reviewer 1 Report

No additional Comments

Author Response

The author would like to express his gratitude for the reviewer's time and effort in reviewing the manuscript.

Reviewer 2 Report

See attached file

Comments for author File: Comments.pdf

Author Response

A point-by-point reply to all comments is provided in the attached pdf file.

Author Response File: Author Response.pdf

Reviewer 3 Report

This paper reports the most recent developments on the McCAD code, an Open Source tool to convert CAD models to the MCNP input format, as required to perform Monte Carlo particle transport simulations for nuclear applications with complex designs. The development of McCAD as an Open Source tool is a very important contribution to neutronics and nuclear engineering of fusion and fission reactors, which makes the subject of the paper suitable for publication in this journal. 

The paper is well structured and written clearly, with adequate references. The new version of the code (1.0) is available in GitHub, which allows the reader to compile it and test it. The improvements described in the paper when compared to the previous version (0.5) are fulfilled: performance has improved, the user interface is simpler, and the lower reliance on third-party applications simplifies the installation process. Along with the updated manual, the paper contributes to a better understanding of the new developments in the code. 

I recommend the paper for publication in its current state, with the following suggestions of minor improvements in the text:

2. Code philosophy and structure

“In 2019, McCAD development took on new path and philosophy:” -> “In 2019, McCAD development took on a new path and philosophy:”

“the textual input defines complex geometrical formations as the resultant of Boolean operations” -> “the textual input defines complex geometrical formations as a result of Boolean operations”

4.3 Supplementary Output

“input solids and its subsolids” -> “input solids and their subsolids”

5. Outlook

“The latter could open the doors” -> “The latter could open the door”

The text is well written and easy to understand. 

Author Response

The author would like to thank the reviewer for their comments and the time taken in reading through the manuscript. All corrections has been implemented.

Reviewer 4 Report

This article introduces a newer stand-alone version of the open-source code McCAD v1.0, which facilitates the conversion of CAD-based geometric models to CSG models widely used in Monte Carlo radiation transport codes. Distinguished from the older versions of McCAD which are integrated with CAD platforms, the McCAD v1.0 has been re-written and re-structured to be more independent and thereby more universal for users. In the manuscript, the authors describe the key conversion algorithms implemented in the newer version. The work is of great reference significance to a wide range of users and developers of nuclear simulation tools. The reviewer would like to recommend the manuscript to be accepted and published once the following minor comments are addressed:

1. It is suggested to state the license of an open-source code, as some readers may be interested.

2. Is McCAD v1.0 able to reproduce all features of the original versions? How do you compare these different versions?

3. In the new McCAD, have you considered (or do you plan to) supporting the “lattice” feature in Monte Carlo codes like MCNP for simpler CSG representation in some applications?

Author Response

Thanks to the reviewer for their  time and effort in reviewing the manuscript. Below is a point-by-point reply to the comments:

1- McCAD is licensed under GNU Lesser General Public License v2.1 (LGPL-2.1). The license has been added to text.

2- This questions reflects a complex situation with the previous and current version. While McCAD v1 decomposition algorithm is based on the previous version, v0.5, the conversion algorithm is completely new! Also the decomposition algorithm has been restructured and refactored. In terms of comparison, the new version includes all the functionalities from the previous one. All solids/surfaces supported in the previous version are also supported in v1, the structure and layout of the cells and voids in the produced MCNP input is different, through. There is an underway effort to benchmark the new version against the old version, as well as other conversion codes such as GEOUNED and SuperMC.

3- So far McCAD development has been driven by fusion/accelerator applications where the use of some features of MCNP, like lattices, are not needed. Expanding the code by adding support for more use cases is definitely on the to do list, but not yet supported in the current version. In terms of the upcoming updates, it will mainly focus on supporting additional surfaces such as cones and spheres. Following that, other MCNP features can be explored and added to the code.