Add native Visual Studio build instructions for Windows

_docs_v7/Build-SU2-Windows.md

@@ -3,22 +3,78 @@ title: Build SU2 on Windows
 permalink: /docs_v7/Build-SU2-Windows/
 ---
 
-This document will guide you through the steps to compile SU2 on Windows using the [Minimalist GNU for Windows
-](http://www.mingw.org/) development environment (MinGW) and [Microsoft MPI](https://docs.microsoft.com/en-us/message-passing-interface/microsoft-mpi).
+This document will guide you through the steps to compile SU2 natively on Windows. Two toolchains are described:
 
-Note that there are multiple other ways of compiling SU2 on Windows (for example using Cygwin, Visual Studio, the Linux Subsystem) and all of them should(!) work one way or the other,
-however, we can only document (and support) a limited number of possibilities. 
+- the Microsoft Visual C++ compiler (MSVC) from Visual Studio, with [Microsoft MPI](https://docs.microsoft.com/en-us/message-passing-interface/microsoft-mpi) for parallel runs,
+- the [Minimalist GNU for Windows](http://www.mingw.org/) development environment (MinGW).
+
+Note that there are multiple other ways of compiling SU2 on Windows (for example using Cygwin or the Windows Subsystem for Linux, where the [Linux/MacOS instructions](/docs_v7/Build-SU2-Linux-MacOS/) apply) and all of them should(!) work one way or the other,
+however, we can only document (and support) a limited number of possibilities.
 
 ---
 
-- [Requirements](#requirements)
-- [Installation of Dependencies](#installation-of-dependencies)
-- [Configuration and Compilation](#configuration-and-compilation)
+- [Building with Visual Studio (MSVC)](#building-with-visual-studio-msvc)
+  - [Requirements](#requirements)
+  - [Installation of Dependencies](#installation-of-dependencies)
+  - [Configuration and Compilation](#configuration-and-compilation)
+  - [Known Limitations](#known-limitations)
+- [Building with MinGW](#building-with-mingw)
 - [Running the executables](#running-the-executables)
 
 ---
 
-## Requirements
+## Building with Visual Studio (MSVC)
+
+### Requirements
+
+- Windows 10 or 11 (64-bit)
+- Python 3 (download [here](https://www.python.org/downloads/windows/) or from the Microsoft Store)
+- [Visual Studio 2022](https://visualstudio.microsoft.com/downloads/) or the Build Tools for Visual Studio 2022, with the "Desktop development with C++" workload
+- Git, if you clone the source code (download [here](https://git-scm.com/download/win))
+- Optional, for parallel runs: Microsoft MPI (download [here](https://www.microsoft.com/en-us/download/details.aspx?id=100593), you need the `msmpisetup.exe` and the `msmpisdk.msi`)
+
+These instructions were tested on Windows 11 with Python 3.10, MSVC 19.44 (Visual Studio 2022 Build Tools) and Microsoft MPI 10.1, building the `develop` branch of SU2. They require a version of SU2 that includes [#2900](https://github.com/su2code/SU2/pull/2900), i.e. the `develop` branch or a release after v8.5.0. SU2 v8.5.0 does not compile with MSVC.
+
+### Installation of Dependencies
+
+- Install Visual Studio or the Build Tools and select the "Desktop development with C++" workload.
+- If you want to run SU2 in parallel, install Microsoft MPI by executing both `msmpisetup.exe` and `msmpisdk.msi`. The SDK installer sets the environment variables `MSMPI_INC` and `MSMPI_LIB64` that are used to find MPI when SU2 is configured. Command prompts that were already open do not see these variables, so open a new one after installing.
+
+Meson and Ninja do not have to be installed, SU2 downloads its own copies during configuration.
+
+### Configuration and Compilation
+
+All commands have to be run from the **x64 Native Tools Command Prompt for VS 2022**, which you can find in the start menu. The regular command prompt does not have the compiler in its path, and the x86 prompt builds 32-bit executables.
+
+Navigate to the SU2 source code directory and configure the build:
+
+```
+python meson.py setup build -Denable-cgns=false --prefix=C:\SU2
+```
+
+Then compile and install:
+
+```
+ninja.exe -C build install
+```
+
+The executables and the Python scripts are installed to the `bin` folder of the prefix, `C:\SU2\bin` in this example.
+
+If Microsoft MPI is installed, the configuration summary contains `Run-time dependency MPI for c found: YES` and SU2 is built with MPI support. Do **not** pass `-Dwith-mpi=enabled`: Meson only detects Microsoft MPI for C, which is all SU2 needs, but forcing MPI also requires the C++ detection, which fails. The line `Run-time dependency MPI for cpp found: NO` is therefore expected.
+
+The remaining options are the same as on Linux and MacOS, see the [Linux/MacOS Configuration and Compilation section](/docs_v7/Build-SU2-Linux-MacOS/#configuration-and-compilation).
+
+### Known Limitations
+
+- CGNS support has to be disabled with `-Denable-cgns=false`, because the HDF5 library that is bundled with CGNS does not compile with MSVC. Meshes in the native SU2 format can be used without restrictions.
+- MSVC prints warnings such as `Command line warning D9002 : ignoring unknown option`, these do not affect the build.
+- At run time SU2 may print `WARNING: SU2 was not compiled for an AVX-capable architecture`. This only concerns performance.
+
+## Building with MinGW
+
+These instructions were written for SU2 v7 and have not been verified with more recent versions.
+
+Requirements:
 
 - Windows 10<sup>*</sup>
 - Python 3.7 (download [here](https://www.python.org/downloads/windows/) or from the Microsoft Store)
@@ -28,19 +84,32 @@ however, we can only document (and support) a limited number of possibilities.
 
 <sup>*</sup>Other version might work, but this has not been verified yet.
 
-
-## Installation of Dependencies
+Installation of dependencies:
 
 - Install Microsoft MPI by simply executing the installers `msmpisetup.exe` and the `msmpisdk.msi`.
 
 - Install MinGW by executing the installer `mingw-w64-install.exe`. Choose Version `8.1.0` and Architecture `x86_64` on the Settings page.
 Everything else can stay on their default values. On the next page set a destination folder and remember it! Click next until everything has been downloaded and installed.
 
-## Configuration and Compilation
+Configuration and compilation:
 
 In the file browser go to the mingw installation directory and execute the file `mingw-w64`. This should open the command prompt. Navigate to the SU2 source code directory (in the command prompt you can change directories using `cd` and list directories using `dir`).
 Now you can follow the steps in the [Linux/MacOS Configuration and Compilation section](/docs_v7/Build-SU2-Linux-MacOS/#configuration-and-compilation). But make sure to use `python meson.py` and `ninja.exe` instead of `./meson.py` and `./ninja`, respectively.
 
+Note that the older MinGW distribution from mingw.org (GCC 6) cannot compile current versions of SU2, use MinGW-w64.
 
 ## Running the executables
-Follow the [installation guide](/docs_v7/SU2-Windows/).
+
+Add the `bin` folder of the installation to your `PATH` and set `SU2_RUN` to the same folder, as described in the [installation guide](/docs_v7/SU2-Windows/). SU2 is then started with
+
+```
+SU2_CFD.exe config.cfg
+```
+
+for a serial run, or with
+
+```
+mpiexec -n 4 SU2_CFD.exe config.cfg
+```
+
+for a parallel run on 4 processes.