Look for game data in usual Steam/GOG installation paths

CMakeLists.txt

@@ -194,13 +194,28 @@ find_package(plog REQUIRED)
 
 if(CMAKE_SYSTEM_NAME STREQUAL "Linux" OR CMAKE_SYSTEM_NAME STREQUAL "OpenBSD")
   message("Building for Linux")
-  add_compile_definitions(POSIX __LINUX__ _USE_OGL_ACTIVE_TEXTURES PRIMARY_HOG=\"d3-linux.hog\")
+  add_compile_definitions(POSIX __LINUX__)
+  set(D3_PRIMARY_HOG "d3-linux.hog")
+  set(D3_STANDARD_PATHS
+    "~/.local/share/Steam/steamapps/common/Descent 3"          # Fedora, arch
+    "~/.steam/debian-installation/steamapps/common/Descent 3"  # Debian & derivatives
+  )
 elseif(CMAKE_SYSTEM_NAME STREQUAL "Darwin")
   message("Building for macOS")
-  add_compile_definitions(POSIX MACOSX=1 _USE_OGL_ACTIVE_TEXTURES PRIMARY_HOG=\"d3-osx.hog\")
+  add_compile_definitions(POSIX MACOSX=1)
+  set(D3_PRIMARY_HOG "d3-osx.hog")
+  set(D3_STANDARD_PATHS
+    "~/Library/Application Support/Steam/steamapps/common/Descent 3/Descent 3.app/Contents/Resources"
+  )
 elseif(CMAKE_SYSTEM_NAME STREQUAL "Windows")
+  set(D3_PRIMARY_HOG "d3-win.hog")
+  set(D3_STANDARD_PATHS
+    "C:\\\\Program Files (x86)\\\\Steam\\\\steamapps\\\\common\\\\Descent 3"
+    "C:\\\\Program Files (x86)\\\\GOG Galaxy\\\\Games\\\\Descent 3"
+  )
+
   # Windows.h defines to avoid as many issues as possible.
-  add_compile_definitions(WIN32_LEAN_AND_MEAN NOMINMAX NODRAWTEXT NOBITMAP NOMCX NOSERVICE PRIMARY_HOG=\"d3-win.hog\"
+  add_compile_definitions(WIN32_LEAN_AND_MEAN NOMINMAX NODRAWTEXT NOBITMAP NOMCX NOSERVICE
           #[[NOGDI]] # We need GDI for now, enable when GDI is actually not needed (or when all windows.h mentions are gone)
   )
 
@@ -238,6 +253,8 @@ elseif(CMAKE_SYSTEM_NAME STREQUAL "Windows")
   add_compile_options("/MP")  # so msbuild builds with multiple processes
 endif()
 
+string(REPLACE ";" "\", \"" D3_STANDARD_PATHS_CPP "${D3_STANDARD_PATHS}")
+
 add_compile_definitions($<$<CONFIG:Release>:RELEASE>)
 add_compile_definitions($<$<CONFIG:Debug>:_DEBUG>)
 

Descent3/init.cpp

@@ -1444,7 +1444,22 @@ void InitIOSystems(bool editor) {
   // Platform dependent paths
   std::filesystem::path platform_dir = std::filesystem::canonical(D3_DATADIR);
   cf_AddBaseDirectory(platform_dir);
-  // TODO: add Steam/registry locations
+
+  std::vector<std::filesystem::path> default_platform_dirs = {
+    D3_STANDARD_PATHS
+  };
+
+  for (const auto& platform_dir: default_platform_dirs) {
+    if (platform_dir.u8string().at(0) == '~') {
+      // On Unix, replace "~" in paths by the runtime $HOME directory
+      std::string base_dir_str = platform_dir.u8string();
+      const std::string home_dir = std::getenv("HOME");
+      base_dir_str.replace(0,1,home_dir);
+      cf_AddBaseDirectory(std::filesystem::path(base_dir_str));
+    } else {
+      cf_AddBaseDirectory(platform_dir);
+    }
+  }
 
   // Add path of executable
   std::filesystem::path exec_path = ddio_GetBasePath();
@@ -1534,7 +1549,7 @@ void InitIOSystems(bool editor) {
 
   // last library opened is the first to be searched for dynamic libs, so put
   // this one at the end to find our newly build script libraries first
-  sys_hid = cf_OpenLibrary(PRIMARY_HOG);
+  sys_hid = cf_OpenLibrary(D3_PRIMARY_HOG);
 
   // Check to see if there is a -mission command line option
   // if there is, attempt to open that hog/mn3 so it can override such

ddio/ddio.h

@@ -318,9 +318,6 @@ void ddio_MouseSetVCoords(int width, int height);
 //	File Operations
 //	---------------------------------------------------------------------------
 
-// Gets the full path of the executable file
-bool ddio_GetBinaryPath(char *exec_path, size_t len);
-
 // deletes a file.  Returns 1 if successful, 0 on failure
 //	This pathname is *RELATIVE* not fully qualified
 int ddio_DeleteFile(const char *name);

ddio/lnxio.cpp

@@ -106,33 +106,3 @@ void ddio_DebugMessage(unsigned err, char *fmt, ...) {
   LOG_DEBUG << buf;
 }
 
-bool ddio_GetBinaryPath(char *exec_path, size_t len) {
-#ifdef MACOSX
-  if (exec_path == NULL || len == 0) {
-    LOG_ERROR << "Invalid arguments";
-    return false;
-  }
-
-  uint32_t size = (uint32_t)len;
-  if (_NSGetExecutablePath(exec_path, &size) != 0) {
-    LOG_ERROR.printf("Buffer too small; need size %u", size);
-    return false;
-  }
-#elif defined(__LINUX__)
-  if (realpath("/proc/self/exe", exec_path) == NULL) {
-   perror("realpath");
-   return false;
-  }
-#else
-  if (GetModuleFileName(NULL, exec_path, len) == 0) {
-    DWORD error = GetLastError();
-    LOG_ERROR << "GetModuleFileName failed!";
-    return false;
-  }
-  exec_path[len - 1] = '\0';
-  return true;
-
-#endif
-  exec_path[len - 1] = '\0';
-  return true;
-}

lib/d3_platform_path.h.in

@@ -21,6 +21,12 @@
 // Platform-specific compile-time defined location of data files
 #define D3_DATADIR "@D3_DATADIR@"
 
+// Standard Descent 3 installation locations for the platform (Steam, GoG...)
+#define D3_STANDARD_PATHS "@D3_STANDARD_PATHS_CPP@"
+
+// .hog file shipped with the game
+#define D3_PRIMARY_HOG "@D3_PRIMARY_HOG@"
+
 // Part of preference path (organization)
 #define D3_PREF_ORG "Outrage Entertainment"