Update README and scripts for improved Qt platform plugin handling; add application icon for macOS

Author: gdmiron

Resources/README-windows.txt

@@ -16,6 +16,14 @@ If windows will show you a warning message "Windows protected your PC", click "M
 
 Once GEM-Fits is running you can pin the program to the Task bar by right-clicking on its icon (on the task bar) and chose pin to task bar. After you close GEM-Fits, the script will create a Start Menu and Desktop shortcut. After the first run you can always start gems using its shortcut.
 
+Always start GEM-Fits via `runshell.bat` or the Start Menu/Desktop shortcut it creates - do not
+double-click `gem-fits-shell.exe` directly inside `GemFits-app\bin`. If you do, and this machine
+already has another Qt installation (Anaconda, Qt Creator, etc.) that sets a
+`QT_QPA_PLATFORM_PLUGIN_PATH` or `QT_PLUGIN_PATH` environment variable, GEM-Fits can fail to start
+with `Could not find the Qt platform plugin "windows"` - `runshell.bat` and its shortcuts point
+these variables at the plugins bundled with this installation before launching, which the raw exe
+does not.
+
 ## Where are my projects?
 
 Modeling projects (including the test projects bundled with this installation, which are copied there automatically on first start) live in `Library\GemFits\projects` in your user home folder (e.g. `C:\Users\<user>\Library\GemFits\projects`). Unlike on macOS, this `Library` folder is not hidden, so it can be opened directly in File Explorer or via the address bar.

Resources/gems3.icns Resources/gemsfits.icnsResources/gems3.icns renamed to Resources/gemsfits.icns

@@ -1,6 +1,14 @@
 rem  Change the path to the actual location of gem-fits-shell executable and Resources
 cd ./GemFits-app/bin
 
+rem Force Qt to use the platform plugin bundled with this app (GemFits-app\plugins\platforms).
+rem Without this, a QT_QPA_PLATFORM_PLUGIN_PATH or QT_PLUGIN_PATH already set on this machine
+rem (e.g. left over from an unrelated Anaconda/PyQt/Qt Creator install) silently overrides Qt's
+rem normal bundled-app lookup, and gem-fits-shell.exe aborts immediately with:
+rem   qt.qpa.plugin: Could not find the Qt platform plugin "windows" in ""
+set "QT_QPA_PLATFORM_PLUGIN_PATH=%CD%\..\plugins\platforms"
+set "QT_PLUGIN_PATH=%CD%\..\plugins"
+
 rem 1. First launch with default location of modeling projects (usually done by the installer)
 rem gem-fits-shell.exe -d > gemsfits.log
 
@@ -22,14 +30,20 @@ rem 5. Create on desktop a shortcut
 @echo off
 setlocal
 set "scriptPath=%~dp0"
-set "targetPath=%scriptPath%GemFits-app\bin\gem-fits-shell.exe"
+rem Shortcuts target runshell.bat itself (not gem-fits-shell.exe directly) so that every
+rem launch - not just the very first one - goes through the QT_QPA_PLATFORM_PLUGIN_PATH fix
+rem above. Pointing a shortcut straight at the exe would skip that fix and could reproduce
+rem the "Could not find the Qt platform plugin" crash on machines with a conflicting Qt env var.
+set "targetPath=%scriptPath%runshell.bat"
+set "workingDir=%scriptPath%"
+set "exePath=%scriptPath%GemFits-app\bin\gem-fits-shell.exe"
 set "iconPath=%scriptPath%GemFits-app\Resources\gemsfits.ico"
 set "startMenuShortcut=%APPDATA%\Microsoft\Windows\Start Menu\Programs\gems-fits-shell.lnk"
 set "desktopShortcut=%USERPROFILE%\Desktop\gems-fits-shell.lnk"
 
 REM Check if required files exist
-IF NOT EXIST "%targetPath%" (
-    echo ERROR: Executable not found: "%targetPath%"
+IF NOT EXIST "%exePath%" (
+    echo ERROR: Executable not found: "%exePath%"
     exit /b
 )
 
@@ -43,6 +57,7 @@ echo Creating Start Menu shortcut...
 echo Set oWS = CreateObject("WScript.Shell") > CreateShortcut.vbs
 echo Set oLink = oWS.CreateShortcut("%startMenuShortcut%") >> CreateShortcut.vbs
 echo oLink.TargetPath = "%targetPath%" >> CreateShortcut.vbs
+echo oLink.WorkingDirectory = "%workingDir%" >> CreateShortcut.vbs
 echo oLink.IconLocation = "%iconPath%" >> CreateShortcut.vbs
 echo oLink.Save >> CreateShortcut.vbs
 cscript //nologo CreateShortcut.vbs
@@ -55,6 +70,7 @@ echo Set oWS = CreateObject("WScript.Shell") > CreateShortcut.vbs
 echo strDesktop = oWS.SpecialFolders("Desktop") >> CreateShortcut.vbs
 echo Set oLink = oWS.CreateShortcut(strDesktop ^& "\gems-fits-shell.lnk") >> CreateShortcut.vbs
 echo oLink.TargetPath = "%targetPath%" >> CreateShortcut.vbs
+echo oLink.WorkingDirectory = "%workingDir%" >> CreateShortcut.vbs
 echo oLink.IconLocation = "%iconPath%" >> CreateShortcut.vbs
 echo oLink.Save >> CreateShortcut.vbs
 cscript //nologo CreateShortcut.vbs

Resources/runshell-windows.bat

@@ -34,10 +34,10 @@ elseif (APPLE)
     # The MACOSX_BUNDLE_ICON_FILE variable is added to the Info.plist
     # generated by CMake. This variable contains the .icns file name,
     # without the path.
-    set(MACOSX_BUNDLE_ICON_FILE gems3.icns)
+    set(MACOSX_BUNDLE_ICON_FILE gemsfits.icns)
 
     # And the following tells CMake where to find and install the file itself.
-    set(app_icon_macos "${PROJECT_SOURCE_DIR}/Resources/gems3.icns")
+    set(app_icon_macos "${PROJECT_SOURCE_DIR}/Resources/gemsfits.icns")
     set_source_files_properties(${app_icon_macos} PROPERTIES
            MACOSX_PACKAGE_LOCATION "Resources")
 
@@ -46,7 +46,7 @@ elseif (APPLE)
     set_target_properties(gem-fits-shell PROPERTIES
         MACOSX_BUNDLE_GUI_IDENTIFIER ch.psi.gems-fits
         MACOSX_BUNDLE_COPYRIGHT  "Copyright (c) 2004-2025 GEMS Development Team"
-        MACOSX_BUNDLE_ICON_FILE gems3.icns
+        MACOSX_BUNDLE_ICON_FILE gemsfits.icns
         MACOSX_BUNDLE_INFO_STRING "GEM Input Parameter Optimization and Inverse Modelling"
         MACOSX_BUNDLE_BUNDLE_VERSION ${PROJECT_VERSION}
         MACOSX_BUNDLE_SHORT_VERSION_STRING ${PROJECT_VERSION_MAJOR}.${PROJECT_VERSION_MINOR}