ofConstants.h). For all other keys, the Unicode code point you'd expect if this key combo (including modifier keys that may be down) was pressed in a text editor (same as codepoint).
The keycode returned by the windowing system, independent of any modifier keys or keyboard layout settings. For ofAppGLFWWindow this value is one of GLFW_KEY_* (.
See also
glfw3.h) - typically, ASCII representation of the symbol on the physical key, so A key always returns 0x41 even if shift, alt, ctrl are down.