cmake . could not find a package configuration file provided by SDL2.

[JJJHolscher]

On my arch machine with sdl2 installed, the cmake . -DRUN_IN_PLACE=TRUE command returns the error

> cmake . -DRUN_IN_PLACE=TRUE
-- The C compiler identification is GNU 13.1.1
-- The CXX compiler identification is GNU 13.1.1
[...]
-- Check size of size_t
-- Check size of size_t - done
CMake Error at src/CMakeLists.txt:40 (find_package):
  Could not find a package configuration file provided by "SDL2" with any of
  the following names:

    SDL2Config.cmake
    sdl2-config.cmake

  Add the installation prefix of "SDL2" to CMAKE_PREFIX_PATH or set
  "SDL2_DIR" to a directory containing one of the above files.  If "SDL2"
  provides a separate development package or SDK, be sure it has been
  installed.


-- Configuring incomplete, errors occurred!

This is after having run the code from https://github.com/minetest/minetest/blob/master/doc/compiling/linux.md

sudo pacman -S base-devel libcurl-gnutls cmake libxi libpng sqlite libogg libvorbis openal freetype2 jsoncpp gmp luajit leveldb ncurses zstd
git clone --depth 1 https://github.com/EleutherAI/minetest.git
cd minetest
git clone --depth 1 https://github.com/minetest/minetest_game.git games/minetest_game
git clone --depth 1 https://github.com/minetest/irrlicht.git lib/irrlichtmt

The minetest version (https://github.com/minetest/minetest.git)

cmake . -DRUN_IN_PLACE=TRUE
make . -j8

Successfully builds bin/minetest after running the above 2 shell scripts.

[JJJHolscher]

I overlooked build_instructions.txt.
After following that and updating the setup.py I got it to work.

Here is my makefile, which should work from any empty repo provided you run linux and installed the necessary system-wide dependencies.

pwd = $(shell pwd)
name = $(notdir $(pwd))
venv = $(pwd)/.venv/bin/python

export IRRLICHT_REPO = "$(pwd)/irrlicht"

define git-clone
	$(eval module_name = $(notdir $1))

	# Add or update the repo as a submodule, or clone it.
	git submodule add $1 || \
	git submodule update --init "$(module_name)" || \
	git clone --depth 1 $1

	cd $(module_name) && git checkout $2
endef

.venv/bin/activate: minetest/bin/minetest
	python -m venv --prompt minetest .venv
	@echo "\nexport MPLBACKEND=''" >> .venv/bin/activate
	. .venv/bin/activate && \
	pip install -e ./minetest && \
	pip install --upgrade protobuf==3.20.1 && \
	cd minetest/scripts && \
	./compile_proto.sh

# cmake . -DRUN_IN_PLACE=TRUE -DBUILD_HEADLESS=1 -DSDL2_DIR="$(pwd)/SDL/build/lib/cmake/SDL2/" && 
minetest/bin/minetest: minetest/games/minetest_game zmqpp/build/max-g++/libzmqpp.a
	cd minetest && \
	cmake . -DRUN_IN_PLACE=TRUE -DBUILD_HEADLESS=0 -DSDL2_DIR= && \
	make -j$(shell nproc)

minetest/games/minetest_game: zmqpp/.git irrlicht/.git minetest/.git minetest_game/.git
	@rm -r minetest/lib/zmqpp
	@rm -r minetest/lib/irrlichtmt
	@ln -s $(pwd)/zmqpp/ minetest/lib/zmqpp
	@ln -s $(pwd)/irrlicht/ minetest/lib/irrlichtmt
	@ln -s $(pwd)/minetest_game/ minetest/games/minetest_game || echo "minetest_game already linked"

minetest_game/.git:
	$(call git-clone,https://github.com/minetest/minetest_game,master)

minetest/.git:
	$(call git-clone,https://github.com/EleutherAI/minetest,develop)

irrlicht/.git:
	$(call git-clone,https://github.com/EleutherAI/irrlicht,headless-rendering)

zmqpp/build/max-g++/libzmqpp.a: zmqpp/.git
	cd zmqpp && make

zmqpp/.git:
	$(call git-clone,https://github.com/zeromq/zmqpp,develop)

SDL/build/bin/sdl2-config: SDL/.git
	mkdir SDL/build
	cd SDL/build && \
	../configure --prefix="$(pwd)/SDL/build" && \
	make && \
	make install

SDL/.git:
	$(call git-clone,https://github.com/libsdl-org/SDL,release-2.26.2)

test: .venv/bin/activate
	. .venv/bin/activate && \
	python -m minetester.scripts.test_loop

clean:
	rm -r .venv
	rm -r irrlicht
	rm -r SDL
	rm -r minetest
	rm -r minetest_game
	rm -r zmqpp