1 files changed, 41 insertions, 0 deletions
diff --git a/CMake/pen-support.c b/CMake/pen-support.c
new file mode 100644
index 000000000..3c3bed0be
--- /dev/null
+++ b/CMake/pen-support.c
@@ -0,0 +1,41 @@
+/*
+  Test Pen/Tablet support availability (Windows).
+
+  Copyright 2026 by Bill Spitzak and others.
+
+  This library is free software. Distribution and use rights are outlined in
+  the file "COPYING" which should have been included with this file.  If this
+  file is missing or damaged, see the license at:
+
+      https://www.fltk.org/COPYING.php
+
+  Please see the following page on how to report bugs and issues:
+
+      https://www.fltk.org/bugs.php
+*/
+
+/*
+  CMake test function: test if this can be compiled.
+  If compilation fails, then Pen/Tablet support can't be built and is disabled.
+*/
+
+/* We require Windows 8 or later features for Pen/Tablet support */
+
+# if !defined(WINVER) || (WINVER < 0x0602)
+#  ifdef WINVER
+#   undef WINVER
+#  endif
+#  define WINVER 0x0602
+# endif
+# if !defined(_WIN32_WINNT) || (_WIN32_WINNT < 0x0602)
+#  ifdef _WIN32_WINNT
+#   undef _WIN32_WINNT
+#  endif
+#  define _WIN32_WINNT 0x0602
+# endif
+
+#include <windows.h>
+
+int main() {
+    return POINTER_CHANGE_FIRSTBUTTON_DOWN; /* required symbol */
+}