desktop integration for Linux, embedded icons on Windows

tools/lammps-gui/CMakeLists.txt

@@ -57,6 +57,12 @@ if(LAMMPS_GUI_USE_PLUGIN)
   set(PLUGIN_LOADER_SRC ${LAMMPS_PLUGINLIB_DIR}/liblammpsplugin.c)
 endif()
 
+# include resource compiler to embed icons into the executable on Windows
+if(CMAKE_SYSTEM_NAME STREQUAL "Windows")
+  enable_language(RC)
+  set(ICON_RC_FILE ${CMAKE_CURRENT_SOURCE_DIR}/lmpicons.rc)
+endif()
+
 # we require Qt 5 and at least version 5.12 at that.
 find_package(Qt5 5.12 REQUIRED COMPONENTS Widgets Charts)
 
@@ -85,6 +91,7 @@ set(PROJECT_SOURCES
   setvariables.h
   stdcapture.cpp
   ${PLUGIN_LOADER_SRC}
+  ${ICON_RC_FILE}
 )
 qt5_add_resources(PROJECT_SOURCES lammpsgui.qrc)
 
@@ -184,6 +191,8 @@ elseif((CMAKE_SYSTEM_NAME STREQUAL "Windows") AND CMAKE_CROSSCOMPILING)
     WORKING_DIRECTORY ${CMAKE_BINARY_DIR})
 elseif(CMAKE_SYSTEM_NAME STREQUAL "Linux")
   install(TARGETS lammps-gui DESTINATION ${CMAKE_INSTALL_BINDIR})
+  install(FILES ${CMAKE_CURRENT_SOURCE_DIR}/lammps-gui.desktop DESTINATION ${CMAKE_INSTALL_DATADIR}/applications/)
+  install(DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/icons/hicolor DESTINATION ${CMAKE_INSTALL_DATADIR}/icons/)
   install(CODE [[
     file(GET_RUNTIME_DEPENDENCIES
       LIBRARIES $<TARGET_FILE:lammps>

tools/lammps-gui/lammps-gui.desktop

@@ -0,0 +1,10 @@
+[Desktop Entry]
+Version=1.0
+Type=Application
+Categories=Science;Engineering;
+Exec=lammps-gui %f
+Name=The LAMMPS GUI
+Terminal=false
+GenericName=MD Simulator
+Keywords=MD Simulation;LAMMPS;Molecular Dynamics;N-Body
+Icon=lammps

tools/lammps-gui/lmpicons.rc

@@ -0,0 +1,2 @@
+id1 ICON icons/lammps.ico
+id2 ICON icons/lmpfile.ico