Icons

KDE_ICON = AUTO

installs the icons into the global KDE directories, whereas

appicondir = $(kde_datadir/myapp/icons
appicon_ICON = AUTO

installs the icons into myapp's specific directory (recommended when the icons are only needed by one application, to avoid cluttering the global directories and prevent name clashes).

For AUTO to work (and for the icon loading to work as well), you need to follow the naming convention: themesize-type-name.png

Where:

You can find the same icon types in the icon chooser dialog.

Examples:

Note that this convention is for the sources only. Upon installation, the icon will be copied to the right directory, simply named name.png.