How to build Aseprite from source in ubuntu 20.04? CMake Warning: "No source or binary directory provided"

Question

I was trying to build Aseprite from its source in Ubuntu 20.04 and got stuck while executing cmake.

I followed all the instructions provided in the install.md file.

This is the output I got after executing cmake :

CMake Warning:
No source or binary directory provided.  Both will be assumed to be the 
same as the current working directory, but note that this warning will 
become a fatal error in future CMake releases.

CMake Deprecation Warning at CMakeLists.txt:16 (cmake_policy):

The OLD behavior for policy CMP0046 will be removed from a future version
of CMake.

The cmake-policies(7) manual explains that the OLD behaviors of all policies are deprecated and that a policy should be set to OLD only under specific short-term circumstances. Projects should be ported to the NEW behavior and not rely on setting a policy to OLD.

-- The C compiler identification is GNU 9.3.0 -- The CXX compiler identification is GNU 9.3.0 CMake Error at /usr/share/cmake-3.16/Modules/CMakeCInformation.cmake:84 (include): include could not find load file:

/home/shree/aseprite/build/laf/cmake/c_flag_overrides.cmake

Call Stack (most recent call first): CMakeLists.txt:31 (project)

-- Check for working C compiler: /usr/bin/cc -- Check for working C compiler: /usr/bin/cc -- works -- Detecting C compiler ABI info -- Detecting C compiler ABI info - done -- Detecting C compile features -- Detecting C compile features - done CMake Error at /usr/share/cmake-3.16/Modules/CMakeCXXInformation.cmake:89 (include): include could not find load file:

/home/shree/aseprite/build/laf/cmake/cxx_flag_overrides.cmake

Call Stack (most recent call first): CMakeLists.txt:31 (project)

-- Check for working CXX compiler: /usr/bin/c++ -- Check for working CXX compiler: /usr/bin/c++ -- works -- Detecting CXX compiler ABI info -- Detecting CXX compiler ABI info - done -- Detecting CXX compile features -- Detecting CXX compile features - done CMake Error at CMakeLists.txt:41 (message): Your Aseprite repository is incomplete, initialize submodules using:

git submodule update --init --recursive

-- Configuring incomplete, errors occurred! See also "/home/shree/aseprite/build/CMakeFiles/CMakeOutput.log".