Add SDL version of allegro5 build as well in separate package.

allegro5/Makefile

 SHELL:=/bin/bash
 
-allegro5:
+allegro5_:
 	git clone https://github.com/liballeg/allegro5.git
 	pushd allegro5 && git checkout 5.2.5.0
 	bash ../ubuntu1804.sh make impl
 	make package
+	bash ../ubuntu1804.sh make impl_sdl
+	make package_sdl
 
-impl:
+prep:
 	apt-get update
 	apt-get install -y freeglut3-dev libgl1-mesa-dev libglu1-mesa-dev mesa-common-dev \
 	                   libxcursor-dev libavfilter-dev \
 	                   libpng-dev libjpeg-dev libfreetype6-dev \
 	                   libxrandr-dev libxinerama-dev libxi-dev \
-	                   libgtk2.0-dev
+	                   libgtk2.0-dev libsdl2-dev
 	update-alternatives --install /usr/bin/c++ c++ /usr/bin/clang++-10 40
 	update-alternatives --install /usr/bin/cc cc /usr/bin/clang-10 40
 	update-alternatives --install /usr/bin/clang++ clang++ /usr/bin/clang++-10 40
 	update-alternatives --install /usr/bin/clang clang /usr/bin/clang-10 40
 	update-alternatives --install /usr/bin/ld ld /usr/bin/ld.lld-10 40
+
+impl:
+	make prep
 	# static build
 	pushd allegro5 && \
 	cmake -DCMAKE_BUILD_TYPE=release -DCMAKE_INSTALL_PREFIX=$$PWD/allegro5_static -DSHARED=off -DSTATIC=on -DWANT_FFMPEG=off -DWANT_TTF=on . && \
 	#sudo make install && \
 	#sudo cp -prv lib/pkgconfig/allegro* /usr/share/pkgconfig/
 
+prep_sdl:
+	make prep
+	apt-get install -y libsdl2-dev
+
+impl_sdl:
+	make prep_sdl
+	# static build
+	pushd allegro5 && \
+	cmake -DCMAKE_BUILD_TYPE=release -DCMAKE_INSTALL_PREFIX=$$PWD/allegro5_static -DALLEGRO_SDL=on -DSHARED=off -DSTATIC=on -DWANT_FFMPEG=off -DWANT_TTF=on . && \
+	make -j $$(nproc) && \
+	make install && \
+	cp -prv lib/pkgconfig/allegro* /usr/share/pkgconfig/
+
 package:
 	rm -rf out
 	mkdir -p out/opt/cppse/build/allegro5/
 	rm -rf allegro5_*_amd64.deb
 	docker run -v "$$(pwd):/src/" rayburgemeestre/fpm-ubuntu:18.04 fpm -v 1.1 -s dir -t deb -n allegro5 --license MPL2 --maintainer "Ray Burgemeestre <ray@cppse.nl>" --description "allegro5 - build dependency" --url "https://github.com/liballeg/allegro5.git" --deb-generate-changes -C /src/out
 
+package_sdl:
+	rm -rf out
+	mkdir -p out/opt/cppse/build/allegro5sdl/
+	cp -prv allegro5/allegro5_static/* out/opt/cppse/build/allegro5sdl/
+	cp -prv allegro5/include/allegro5/internal/aintern_bitmap.h out/opt/cppse/build/allegro5sdl/include/allegro5/internal/aintern_bitmap.h
+	cp -prv allegro5/include/allegro5/internal/* out/opt/cppse/build/allegro5sdl/include/allegro5/internal/
+	cp -prv allegro5/include/allegro5/platform/* out/opt/cppse/build/allegro5sdl/include/allegro5/platform/
+	rm -rf allegro5sdl_*_amd64.deb
+	docker run -v "$$(pwd):/src/" rayburgemeestre/fpm-ubuntu:18.04 fpm -v 1.1 -s dir -t deb -n allegro5sdl --license MPL2 --maintainer "Ray Burgemeestre <ray@cppse.nl>" --description "allegro5 - SDL version - build dependency" --url "https://github.com/liballeg/allegro5.git" --deb-generate-changes -C /src/out
+
 clean:
 	rm -rf allegro5
 	rm -rf out
+	rm -rf allegro5*.deb
+	rm -rf allegro5*.changes
 
 shell:
 	FLAGS="-i --privileged" bash ../ubuntu1804.sh /bin/bash