Use user provided lib/irrlichtmt if available (#11276)

Use user provided lib/irrlichtmt if available

Make it possible for a user to provide the IrrlichtMt dependency as
subdirectory at `lib/irrlichtmt`.
The subdirectory is added with the `EXCLUDE_FROM_ALL` flag to prevent
`libirrlichtmt.a` or other header files to be installed.

This enables the user to do the following to satisfy the IrrlichtMt
dependency:

git clone --depth 1 https://github.com/minetest/irrlicht.git lib/irrlichtmt
cmake . -DRUN_IN_PLACE=TRUE

diff --git a/.gitignore b/.gitignore
index 9db060aadd8c528ab176001d8931c961f1e17907..df1386bce4629c3041a9ad0d791f21fde3378e52 100644 (file)
--- a/.gitignore
+++ b/.gitignore
@@ -106,3 +106,6 @@ CMakeDoxy*
 compile_commands.json
 *.apk
 *.zip
+
+# Optional user provided library folder
+lib/irrlichtmt

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 1f90847eaa3cb070de9bf58a1e69cf6c5b0eeb99..42b3435405e0da84178166827b7cf76c94591695 100644 (file)
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -58,11 +58,27 @@ set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${CMAKE_SOURCE_DIR}/cmake/Modules/")
 
 
 # This is done here so that relative search paths are more reasonable
-find_package(Irrlicht)
-if(BUILD_CLIENT AND NOT IRRLICHT_FOUND)
-       message(FATAL_ERROR "IrrlichtMt is required to build the client, but it was not found.")
-elseif(NOT IRRLICHT_INCLUDE_DIR)
-       message(FATAL_ERROR "Irrlicht or IrrlichtMt headers are required to build the server, but none found.")
+if(EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/lib/irrlichtmt")
+       message(STATUS "Using user-provided IrrlichtMt at subdirectory 'lib/irrlichtmt'")
+       # tell IrrlichtMt to create a static library
+       set(BUILD_SHARED_LIBS OFF CACHE BOOL "Build shared library" FORCE)
+       add_subdirectory(lib/irrlichtmt EXCLUDE_FROM_ALL)
+       unset(BUILD_SHARED_LIBS CACHE)
+
+       if(NOT TARGET IrrlichtMt)
+               message(FATAL_ERROR "IrrlichtMt project is missing a CMake target?!")
+       endif()
+
+       # set include dir the way it would normally be
+       set(IRRLICHT_INCLUDE_DIR "${CMAKE_CURRENT_SOURCE_DIR}/lib/irrlichtmt/include")
+       set(IRRLICHT_LIBRARY IrrlichtMt)
+else()
+       find_package(Irrlicht)
+       if(BUILD_CLIENT AND NOT IRRLICHT_FOUND)
+               message(FATAL_ERROR "IrrlichtMt is required to build the client, but it was not found.")
+       elseif(NOT IRRLICHT_INCLUDE_DIR)
+               message(FATAL_ERROR "Irrlicht or IrrlichtMt headers are required to build the server, but none found.")
+       endif()
 endif()
 
 include(CheckSymbolExists)

diff --git a/README.md b/README.md
index 0136876851c0de4fd65351e13268fb7d64109a97..0cd134f27beb9eac49a6f6ae595f1b16daa17623 100644 (file)
--- a/README.md
+++ b/README.md
@@ -177,6 +177,10 @@ Download minetest_game (otherwise only the "Development Test" game is available)
 
     git clone --depth 1 https://github.com/minetest/minetest_game.git games/minetest_game
 
+Download IrrlichtMt to `lib/irrlichtmt`, it will be used to satisfy the IrrlichtMt dependency that way:
+
+    git clone --depth 1 https://github.com/minetest/irrlicht.git lib/irrlichtmt
+
 Download source, without using Git:
 
     wget https://github.com/minetest/minetest/archive/master.tar.gz
@@ -191,6 +195,14 @@ Download minetest_game, without using Git:
     mv minetest_game-master minetest_game
     cd ..
 
+Download IrrlichtMt, without using Git:
+
+    cd lib/
+    wget https://github.com/minetest/irrlicht/archive/master.tar.gz
+    tar xf master.tar.gz
+    mv irrlicht-master irrlichtmt
+    cd ..
+
 #### Build
 
 Build a version that runs directly from the source directory: