Formally drop support for building with upstream Irrlicht

It stopped working with (at least) the last commit.

.github/workflows/build.yml

@@ -132,7 +132,7 @@ jobs:
  - name: Install deps
  run: |
  source ./util/ci/common.sh
- install_linux_deps --old-irr clang-9
+ install_linux_deps clang-9
 
  - name: Build prometheus-cpp
  run: |

CMakeLists.txt

@@ -78,7 +78,6 @@ if(NOT "${IRRLICHTMT_BUILD_DIR}" STREQUAL "")
  # IrrlichtMtConfig.cmake
  message(FATAL_ERROR "Could not find IrrlichtMtConfig.cmake in ${IRRLICHTMT_BUILD_DIR}/cmake.")
  endif()
-# This is done here so that relative search paths are more reasonable
 elseif(EXISTS "${CMAKE_CURRENT_SOURCE_DIR}/lib/irrlichtmt")
  message(STATUS "Using user-provided IrrlichtMt at subdirectory 'lib/irrlichtmt'")
  if(BUILD_CLIENT)
@@ -108,9 +107,9 @@ else()
 
  include(MinetestFindIrrlichtHeaders)
  if(NOT IRRLICHT_INCLUDE_DIR)
- message(FATAL_ERROR "Irrlicht or IrrlichtMt headers are required to build the server, but none found.\n${explanation_msg}")
+ message(FATAL_ERROR "IrrlichtMt headers are required to build the server, but none found.\n${explanation_msg}")
  endif()
- message(STATUS "Found Irrlicht headers: ${IRRLICHT_INCLUDE_DIR}")
+ message(STATUS "Found IrrlichtMt headers: ${IRRLICHT_INCLUDE_DIR}")
  add_library(IrrlichtMt::IrrlichtMt INTERFACE IMPORTED)
  # Note that we can't use target_include_directories() since that doesn't work for IMPORTED targets before CMake 3.11
  set_target_properties(IrrlichtMt::IrrlichtMt PROPERTIES

README.md

@@ -223,8 +223,8 @@ Run it:
 - You can disable the client build by specifying `-DBUILD_CLIENT=FALSE`.
 - You can select between Release and Debug build by `-DCMAKE_BUILD_TYPE=<Debug or Release>`.
  - Debug build is slower, but gives much more useful output in a debugger.
-- If you build a bare server you don't need to have the Irrlicht or IrrlichtMt library installed.
- - In that case use `-DIRRLICHT_INCLUDE_DIR=/some/where/irrlicht/include`.
+- If you build a bare server you don't need to compile IrrlichtMt, just the headers suffice.
+ - In that case use `-DIRRLICHT_INCLUDE_DIR=/some/where/irrlichtmt/include`.
 
 - Minetest will use the IrrlichtMt package that is found first, given by the following order:
  1. Specified `IRRLICHTMT_BUILD_DIR` CMake variable

cmake/Modules/MinetestFindIrrlichtHeaders.cmake

@@ -1,21 +1,13 @@
-# Locate Irrlicht or IrrlichtMt headers on system.
+# Locate IrrlichtMt headers on system.
 
-foreach(libname IN ITEMS IrrlichtMt Irrlicht)
- string(TOLOWER "${libname}" libname2)
-
- find_path(IRRLICHT_INCLUDE_DIR NAMES irrlicht.h
- DOC "Path to the directory with IrrlichtMt includes"
- PATHS
- /usr/local/include/${libname2}
- /usr/include/${libname2}
- /system/develop/headers/${libname2} #Haiku
- PATH_SUFFIXES "include/${libname2}"
- )
-
- if(IRRLICHT_INCLUDE_DIR)
- break()
- endif()
-endforeach()
+find_path(IRRLICHT_INCLUDE_DIR NAMES irrlicht.h
+ DOC "Path to the directory with IrrlichtMt includes"
+ PATHS
+ /usr/local/include/irrlichtmt
+ /usr/include/irrlichtmt
+ /system/develop/headers/irrlichtmt #Haiku
+ PATH_SUFFIXES "include/irrlichtmt"
+)
 
 # Handholding for users
 if(IRRLICHT_INCLUDE_DIR AND (NOT IS_DIRECTORY "${IRRLICHT_INCLUDE_DIR}" OR

util/ci/common.sh

@@ -9,9 +9,6 @@ install_linux_deps() {
 
  if [[ "$1" == "--no-irr" ]]; then
  shift
- elif [[ "$1" == "--old-irr" ]]; then
- shift
- pkgs+=(libirrlicht-dev)
  else
  wget "https://github.com/minetest/irrlicht/releases/download/1.9.0mt6/ubuntu-bionic.tar.gz"
  sudo tar -xaf ubuntu-bionic.tar.gz -C /usr/local