add Github CI

.github/workflows/build.sh

@@ -0,0 +1,36 @@
+set -e o pipefail
+source .github/workflows/gh_ci_envvars.sh
+
+
+GH_MYMAKE_ARGS=""
+GH_AUTOTOOLS_CXXFLAGS="-W -Wall -Wextra -Wno-unused-parameter -Wno-maybe-uninitialized"
+
+HYPERROGUE_USE_GLEW=$GH_HYP_GLEW
+export HYPERROGUE_USE_GLEW=${HYPERROGUE_USE_GLEW: -1}
+
+HYPERROGUE_USE_PNG=$GH_HYP_PNG
+export HYPERROGUE_USE_PNG=${HYPERROGUE_USE_PNG: -1}
+
+HYPERROGUE_USE_ROGUEVIZ=$GH_HYP_RVIZ
+export HYPERROGUE_USE_ROGUEVIZ=${HYPERROGUE_USE_ROGUEVIZ: -1}
+if [[ "$GH_HYP_RVIZ" == "rviz_1" ]]; then
+  GH_MYMAKE_ARGS+=" -rv"
+  GH_AUTOTOOLS_CXXFLAGS+=" -DCAP_ROGUEVIZ=1"
+fi
+
+export CC=$GH_COMPILER
+export CXX=${CC%cc}++
+
+if [[ "$GH_BUILDSYS" == "makefile" ]]; then
+  make -f Makefile.simple
+elif [[ "$GH_BUILDSYS" == "autotools" ]]; then
+  autoreconf -vfi
+  ./configure CXXFLAGS="${GH_AUTOTOOLS_CXXFLAGS}"
+  make
+elif [[ "$GH_BUILDSYS" == "mymake" ]]; then
+  make -f Makefile.simple mymake
+  ./mymake $GH_MYMAKE_ARGS
+  mv hyper hyperrogue
+else
+  exit 'unknown build system'
+fi