From ffcf8bd0b78255ad7ad3a62a5826c1fa6096cd5e Mon Sep 17 00:00:00 2001
From: ManoloFLTK <41016272+ManoloFLTK@users.noreply.github.com>
Date: Sun, 27 Oct 2019 08:37:33 +0100
Subject: Documentation: make clear that "Using OpenGL in Normal FLTK Windows"
 isn't useful with macOS.

---
 documentation/src/opengl.dox | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

(limited to 'documentation/src')

diff --git a/documentation/src/opengl.dox b/documentation/src/opengl.dox
index 35b39e4a7..94c13eb17 100644
--- a/documentation/src/opengl.dox
+++ b/documentation/src/opengl.dox
@@ -14,7 +14,7 @@ OpenGL calls to draw the display. Your main program should call
 (somewhat later) FLTK will call \p draw().
 
 With a bit of care you can also use OpenGL to draw into
-normal FLTK windows. This allows you to use Gouraud shading for
+normal FLTK windows (see \ref opengl_normal below). This allows you to use Gouraud shading for
 drawing your widgets.  To do this you use the
 \ref opengl_gl_start "gl_start()" and
 \ref opengl_gl_finish "gl_finish()"
@@ -199,6 +199,10 @@ and OpenGL under macOS (see \ref osissues_retina)
 
 \section opengl_normal Using OpenGL in Normal FLTK Windows
 
+\note Drawing both with OpenGL and Quartz in a normal FLTK window is not possible
+with the macOS platform. This technique is therefore not useful under macOS because
+it permits nothing more than what is possible with class Fl_Gl_Window.
+
 You can put OpenGL code into the \p draw() method, as described in
 \ref subclassing_drawing
 in the previous chapter, or into the code for a
-- 
cgit v1.2.3