6e407cb169
On the Windows platform Cairo drawings must be flushed explicitly. This is done in Fl_Cairo_Window after calling the draw callback but it was neither done nor documented in test/cairo_test.cxx when using another type of Window with its overloaded draw() method, i.e. when FLTK was configured with --enable-cairoext or CMake OPTION_CAIROEXT. Note: user code must either explicitly flush the Cairo drawings as done here or destroy the Cairo context which is not done in this demo because the Cairo context should be kept alive.
README - Fast Light Tool Kit (FLTK) Version 1.4.0
WHAT IS FLTK?
The Fast Light Tool Kit ("FLTK", pronounced "fulltick") is a
cross-platform C++ GUI toolkit for UNIX®/Linux® (X11 or
Wayland), Microsoft® Windows®, and macOS®.
FLTK provides modern GUI functionality without the bloat and
supports 3D graphics via OpenGL® and its built-in GLUT
emulation. It was originally developed by Mr. Bill Spitzak
and is currently maintained by a small group of developers
across the world with a central repository on GitHub.
For more information see README.txt:
https://github.com/fltk/fltk/blob/master/README.txt
