2 files changed, 9 insertions, 9 deletions
diff --git a/src/drivers/GDI/Fl_GDI_Image_Surface_Driver.cxx b/src/drivers/GDI/Fl_GDI_Image_Surface_Driver.cxx
index 54a4a038f..933593e6d 100644
--- a/src/drivers/GDI/Fl_GDI_Image_Surface_Driver.cxx
+++ b/src/drivers/GDI/Fl_GDI_Image_Surface_Driver.cxx
@@ -34,7 +34,7 @@ public:
   Window pre_window;
   HDC _sgc;
   int _savedc;
-  Fl_GDI_Image_Surface_Driver(int w, int h, int high_res);
+  Fl_GDI_Image_Surface_Driver(int w, int h, int high_res, Fl_Offscreen off);
   ~Fl_GDI_Image_Surface_Driver();
   void set_current();
   void translate(int x, int y);
@@ -45,13 +45,13 @@ public:
 
 Fl_Image_Surface_Driver *Fl_Image_Surface_Driver::newImageSurfaceDriver(int w, int h, int high_res, Fl_Offscreen off)
 {
-  return new Fl_GDI_Image_Surface_Driver(w, h, high_res);
+  return new Fl_GDI_Image_Surface_Driver(w, h, high_res, off);
 }
 
 
-Fl_GDI_Image_Surface_Driver::Fl_GDI_Image_Surface_Driver(int w, int h, int high_res) : Fl_Image_Surface_Driver(w, h, high_res, 0) {
+Fl_GDI_Image_Surface_Driver::Fl_GDI_Image_Surface_Driver(int w, int h, int high_res, Fl_Offscreen off) : Fl_Image_Surface_Driver(w, h, high_res, 0) {
   previous = 0;
-  offscreen = CreateCompatibleBitmap( (fl_graphics_driver->gc() ? (HDC)fl_graphics_driver->gc() : fl_GetDC(0) ) , w, h);
+  offscreen = off ? off : CreateCompatibleBitmap( (fl_graphics_driver->gc() ? (HDC)fl_graphics_driver->gc() : fl_GetDC(0) ) , w, h);
   driver(new Fl_Translated_GDI_Graphics_Driver);
   _sgc = NULL;
 }
diff --git a/src/drivers/Quartz/Fl_Quartz_Image_Surface_Driver.cxx b/src/drivers/Quartz/Fl_Quartz_Image_Surface_Driver.cxx
index cb22904aa..2404c531f 100644
--- a/src/drivers/Quartz/Fl_Quartz_Image_Surface_Driver.cxx
+++ b/src/drivers/Quartz/Fl_Quartz_Image_Surface_Driver.cxx
@@ -30,7 +30,7 @@ class Fl_Quartz_Image_Surface_Driver : public Fl_Image_Surface_Driver {
   virtual void end_current_();
 public:
   Window pre_window;
-  Fl_Quartz_Image_Surface_Driver(int w, int h, int high_res);
+  Fl_Quartz_Image_Surface_Driver(int w, int h, int high_res, Fl_Offscreen off);
   ~Fl_Quartz_Image_Surface_Driver();
   void set_current();
   void translate(int x, int y);
@@ -39,17 +39,17 @@ public:
 };
 
 
-Fl_Image_Surface_Driver *Fl_Image_Surface_Driver::newImageSurfaceDriver(int w, int h, int high_res, Fl_Offscreen)
+Fl_Image_Surface_Driver *Fl_Image_Surface_Driver::newImageSurfaceDriver(int w, int h, int high_res, Fl_Offscreen off)
 {
-  return new Fl_Quartz_Image_Surface_Driver(w, h, high_res);
+  return new Fl_Quartz_Image_Surface_Driver(w, h, high_res, off);
 }
 
 
-Fl_Quartz_Image_Surface_Driver::Fl_Quartz_Image_Surface_Driver(int w, int h, int high_res) : Fl_Image_Surface_Driver(w, h, high_res, 0) {
+Fl_Quartz_Image_Surface_Driver::Fl_Quartz_Image_Surface_Driver(int w, int h, int high_res, Fl_Offscreen off) : Fl_Image_Surface_Driver(w, h, high_res, 0) {
   int W = high_res ? 2*w : w;
   int H = high_res ? 2*h : h;
   CGColorSpaceRef lut = CGColorSpaceCreateDeviceRGB();
-  offscreen = CGBitmapContextCreate(calloc(W*H,4), W, H, 8, W*4, lut, kCGImageAlphaPremultipliedLast);
+  offscreen = off ? off : CGBitmapContextCreate(calloc(W*H,4), W, H, 8, W*4, lut, kCGImageAlphaPremultipliedLast);
   CGColorSpaceRelease(lut);
   driver(new Fl_Quartz_Graphics_Driver);
   CGContextTranslateCTM(offscreen, 0.5, -0.5); // as when drawing to a window