======Qt Creator IDE======

=====Debugging with Qt Creator=====
This is a very short tutorial on how to setup Qt Creator on Windows as your debugging environment for Photivo. It is based on Qt Creator 2.3 and assumes you are familiar with [[download:windows#compiling_photivo|compiling Photivo on Windows]] and have setup your toolchain as explained there.

<note>For full debugging support you need to compile all involved dependencies with debug symbols. Consult the [[download:windows#notes_on_building_debug_libraries|debug notes on the Windows Build page]] for further information.

You actually can run the debugger with some non-debug dependencies and most likely that will work fine as long as you only use those parts of Photivo that don’t rely on those dependencies. In my experience a segfault happens when Photivo with the debugger attached tries to access a non-debug dependency. Example: Debugging with a non-debug lensfun DLL will work as long as you do not actually use the lensfun tools. Effectively this means you must compile a debug version of at least Qt. Debug versions of the other libs might or might not be necessary.</note>

  - Start Qt Creator and go to **Tools › Options**.
  - On the **Qt4** page add a Qt installation: **Add** button, then **Browse** for the appropriate ''qmake.exe''.
  - On the **Tool Chains** page **Add** a **MinGW** toolchain and set the **Compiler path** to the appropriate ''g++.exe''. Qt Creator will try to automatically set **Debugger** and **ABI** accordingly. Make sure the debugger is ''C:\tc\MinGW32\bin\gdb-python27.exe''. (This Python enabled debugger crashes for me with the TDM 4.6.1 toolchain and Qt Creator 2.4.1. The non-python version ''gdb.exe'' seems to work with Qt Creator 2.5 beta, despire an error message about missing “Qt debugging helpers”.)
  - Open ''photivoProject.pro''. When the **Project Setup** dialog appears make sure **Use Shadow Building** is checked and you have an entry for release and debug version. Photivo’s Mercurial repository is configured to ignore paths starting with “build”, so it’s a good idea to choose names accordingly.
  - In the left sidebar go to the **Projects** page and under **Edit build configuration** switch to the **Debug** config.
  - Under **Build Steps** open the details for **Make**. If necessary change the make program to Msys’s make (i.e. ''C:\tc\MinGW32\msys\bin\make.exe'') is known to work. I had problems with the one from MinGW (that Qt selects by default) and multicore compiling.
  -  Setup ''make'' for your CPU cores, i.e. in **Make arguments** enter ''-j2'' for a dual-core CPU, ''-j4'' for a quad-core CPU etc.
  - Open the **Build Environment** details. You need to add a couple of paths here. Adding  all of this to your system environment should work as well, but I never tested it that way.
    * Add all needed ''bin'' folders to the ''PATH'' variable. Those are:\\ C:\tc\MinGW32\bin\\ C:\tc\MinGW32\qt\bin\\ C:\tc\MinGW32\qt\lib\\ C:\tc\MinGW32\msys\bin\\ C:\tc\MinGW32\my\bin\\ Some may already have been added automatically by Qt Creator. Make sure to use the backslash \ as the path delimiter.
    * Add ''LDFLAGS'' and set it to ''-LC:/tc/MinGW32/my/lib'' (forward slashes!)
    * Add ''CFLAGS'' and set it to ''-IC:/tc/MinGW32/my/include'' (forward slashes!)
    * Add ''CXXFLAGS'' and set it to ''-IC:/tc/MinGW32/my/include'' (forward slashes!)
    * Add ''PKG_CONFIG_PATH'' and set it to ''C:/tc/MinGW32/my/lib/pkgconfig'' (forward slashes!)

Assuming your MinGW toolchain is correct and you successfully built all dependencies debugging should work now.

=====Additional information for gcc 4.7 toolchain=====
    * Problem: QtCreator doesn't recognize the Qt installation (in my case Qt 4.8.2).\\ Solution: Copy ''libwinpthread-1.dll'' into qt\bin folder.

=====Multithreaded make in Creator=====
When compiling via pure MinGW without Msys – as is the case in Qt Creator – //make// does not recognise the ''-j'' switch properly, i.e. compiling is single-threaded and slow. You can solve this in Creator’s **Build Environment** settings (see above). Define
  MAKE_COMMAND=mingw32-make -j4
and you’re good. Instead of ''4'' use your number of processor cores.