Android compilation on Windows (Quick overview)

Android compilation is a bit troublesome.

If you're on Windows, you can compile Assimp using these:

• https://ninja-build.org/ <-Ninja for building
  
• https://cmake.org/download/ <-CMake for generating projects
  
• https://developer.android.com/studio/index.html <-Android SDK and NDK (required, you will also need to download the minimum Assimp Android API level, which is level 9)
• Toolchain file located at: <NDK>/build/cmake/android.toolchain.cmake
  
  

The NDK version used to compile was r14b.

Sorry for not posting the details, as I'm a little busy now, but basically, you will:

• Install the SDK and NDK (that are downloadable from Android Studio)
  
• Thats important to check if all Android SDK envoriment variables are configured (here I have: ANDROID_NDK, JAVA_HOME, JDK_ROOT, NDK_HOME, NDKROOT)
  
• Extract Android CMake Toolchain to any folder you want
  
• Extract CM ake-GUI, and preferentially, extract Ninja at the same folder
  
• Thats important to check if your system can find Ninja via envoriment variables. You should have your PATH variable pointing to Ninja folder
  
• Start CMake-GUI, point the input folder to the folder where you extracted Assimp source
  
• Set the output folder to any folder where you want the project to be build
  
• Click on "Configure", and at the settings, select "Ninja Makefiles" specifying the toolchain
  
• Select your extracted toolchain path in the textbox
  
• If everything is ok, CMake-GUI will expand all Assimp compilation options, you can leave them that way, only disabling STL importer, as it´s not compilable for Android afaik
  
• By clicking "Generate", CMake-GUI will generate the project at the folder you've previously selected
  
• Start a Windows CMD session at the project folder (Shift+Right click on Explorer)
  
• Type "Ninja" and press ENTER
  
• If everything is ok, Ninja will build "libassimp.so" inside project "Code" folder
  

Here are the Toolchains I use for Android compiling on Windows (one for x86 architectures, and the another for armv7): https://drive.google.com/open?id=0ByIuTq27JG1qVjF4dDFSVW1tN2M