This article describes the steps to build OCCT libraries for Android from a complete source package with GNU make (makefiles) on Windows 7 and Ubuntu 15.10.

The steps on Windows and Ubuntu are similar. There is the only one difference: makefiles are built with mingw32-make on Windows and native GNU make on Ubuntu.

Required tools (download and install if it is required):

CMake v3.7+ https://www.cmake.org/cmake/resources/software.html
Android NDK rev.10+ https://developer.android.com/tools/sdk/ndk/index.html
GNU Make: MinGW v4.82+ for Windows (https://sourceforge.net/projects/mingw/files/), GNU Make 4.0 for Ubuntu.

Prerequisites

In toolchain file $CASROOT/adm/templates/android.toolchain.config.cmake:

Set CMAKE_ANDROID_NDK variable equal to your Android NDK path.
Set CMAKE_ANDROID_STL_TYPE variable to specify which C++ standard library to use.

The default value of CMAKE_ANDROID_STL_TYPE is gnustl_shared (GNU libstdc++ Shared)

Generation of makefiles using CMake GUI tool

Run GUI tool provided by CMake: cmake-gui

Tools configuration

Specify the root folder of OCCT ($CASROOT, which contains CMakelists.txt file) by clicking Browse Source.
Specify the location (build folder) for Cmake generated project files by clicking Browse Build.

Click Configure button. It opens the window with a drop-down list of generators supported by CMake project.

Select "MinGW Makefiles" item from the list

Choose "Specify toolchain file for cross-compiling"
Click "Next"

Specify a toolchain file at the next dialog by android.toolchain.config.cmake . It is contained by cross-compilation toolchain for CMake
Click "Finish"

If on Windows the message is appeared: "CMake Error: CMake was unable to find a build program corresponding to "MinGW Makefiles" CMAKE_MAKE_PROGRAM is not set. You probably need to select a different build tool.", specify CMAKE_MAKE_PROGRAM to mingw32-make executable.

OCCT Configuration

How to configure OCCT, see "OCCT Configuration" section of Building with CMake

Generation of makefiles

Click Generate button and wait until the generation process is finished. Then makefiles will appear in the build folder (e.g. D:/occt/build-android ).

Generation of makefiles using CMake from the command line

Alternatively one may specify the values without a toolchain file:

cmake -G "MinGW Makefiles" -DCMAKE_SYSTEM_NAME=Android -DCMAKE_ANDROID_NDK=D:/DevTools/android-ndk-r13b -DCMAKE_ANDROID_STL_TYPE=gnustl_shared -DCMAKE_SYSTEM_VERSION=15 -DCMAKE_ANDROID_ARCH_ABI=armeabi-v7a -DCMAKE_MAKE_PROGRAM=D:/DevTools/MinGW/bin/mingw32-make.exe -D3RDPARTY_DIR=D:/occt-3rdparty D:/occt

Building makefiles of OCCT

Open console and go to the build folder. Type "mingw32-make" (Windows) or "make" (Ubuntu) to start build process.

mingw32-make

or

make

Parallel building can be started with using **"-jN"** argument of "mingw32-make/make", where N is the number of building threads.

mingw32-make -j4

or

make -j4

Install built OCCT libraries

Type "mingw32-make/make" with argument "install" to place the libraries to the install folder (see "OCCT Configuration" section of Building with CMake)

mingw32-make install

or

make install