STR#3444: Add MacOS support for application rescaling (not quite complete)

With this, most MacOS FLTK app can be scaled with command/+/-/0/ keystrokes.
A scaling problem remains, visible in test/cube, where the "Test" string is not positioned correctly.

GLUT apps can also be scaled (across platforms).

SVG images are re-rasterized after app scaling for optimal drawing.

git-svn-id: file:///fltk/svn/fltk/branches/branch-1.4@12594 ea41ed52-d2ee-0310-a9c1-e6b18d33e121

1 files changed, 7 insertions, 1 deletions

diff --git a/src/drivers/Cocoa/Fl_Cocoa_Screen_Driver.H b/src/drivers/Cocoa/Fl_Cocoa_Screen_Driver.H
index 3335a39ff..5e318a2e3 100644
--- a/src/drivers/Cocoa/Fl_Cocoa_Screen_Driver.H
+++ b/src/drivers/Cocoa/Fl_Cocoa_Screen_Driver.H
@@ -4,7 +4,7 @@
 // Definition of Apple Cocoa Screen interface
 // for the Fast Light Tool Kit (FLTK).
 //
-// Copyright 2010-2016 by Bill Spitzak and others.
+// Copyright 2010-2017 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
@@ -97,6 +97,12 @@ public:
   // --- compute dimensions of an Fl_Offscreen
   virtual void offscreen_size(Fl_Offscreen o, int &width, int &height);
   virtual float retina_factor() { return 2; }
+  
+  virtual APP_SCALING_CAPABILITY rescalable() { return SYSTEMWIDE_APP_SCALING; }
+  virtual float scale(int n) {return scale_;}
+  virtual void scale(int n, float f) { scale_ = f;}
+private:
+  float scale_;
 };