Remove all uses of the fl_gc global variable. Towards a clean driver model.

fl_gc remains usable by the application as a hook into the system.

git-svn-id: file:///fltk/svn/fltk/branches/branch-1.3-porting@11189 ea41ed52-d2ee-0310-a9c1-e6b18d33e121

1 files changed, 17 insertions, 6 deletions

diff --git a/src/drivers/GDI/Fl_GDI_Graphics_Driver.cxx b/src/drivers/GDI/Fl_GDI_Graphics_Driver.cxx
index 3bc9fedbe..74cd6a69d 100644
--- a/src/drivers/GDI/Fl_GDI_Graphics_Driver.cxx
+++ b/src/drivers/GDI/Fl_GDI_Graphics_Driver.cxx
@@ -27,6 +27,17 @@ const char *Fl_GDI_Graphics_Driver::class_id = "Fl_GDI_Graphics_Driver";
 // FIXME: move to printer graphics driver
 const char *Fl_GDI_Printer_Graphics_Driver::class_id = "Fl_GDI_Printer_Graphics_Driver";
 
+/* Reference to the current device context
+ For back-compatibility only. The preferred procedure to get this reference is
+ Fl_Surface_Device::surface()->driver()->get_gc().
+ */
+HDC fl_gc = 0;
+
+void Fl_Graphics_Driver::global_gc()
+{
+  fl_gc = (HDC)get_gc();
+}
+
 /*
  * By linking this module, the following static method will instatiate the
  * MSWindows GDI Graphics driver as the main display driver.
@@ -87,7 +98,7 @@ char Fl_GDI_Graphics_Driver::can_do_alpha_blending() {
 }
 
 HDC fl_makeDC(HBITMAP bitmap) {
-  HDC new_gc = CreateCompatibleDC(fl_gc);
+  HDC new_gc = CreateCompatibleDC((HDC)fl_graphics_driver->get_gc());
   SetTextAlign(new_gc, TA_BASELINE|TA_LEFT);
   SetBkMode(new_gc, TRANSPARENT);
 #if USE_COLORMAP
@@ -98,26 +109,26 @@ HDC fl_makeDC(HBITMAP bitmap) {
 }
 
 void Fl_GDI_Graphics_Driver::copy_offscreen(int x,int y,int w,int h,HBITMAP bitmap,int srcx,int srcy) {
-  HDC new_gc = CreateCompatibleDC(fl_gc);
+  HDC new_gc = CreateCompatibleDC(gc);
   int save = SaveDC(new_gc);
   SelectObject(new_gc, bitmap);
-  BitBlt(fl_gc, x, y, w, h, new_gc, srcx, srcy, SRCCOPY);
+  BitBlt(gc, x, y, w, h, new_gc, srcx, srcy, SRCCOPY);
   RestoreDC(new_gc, save);
   DeleteDC(new_gc);
 }
 
 void Fl_GDI_Graphics_Driver::copy_offscreen_with_alpha(int x,int y,int w,int h,HBITMAP bitmap,int srcx,int srcy) {
-  HDC new_gc = CreateCompatibleDC(fl_gc);
+  HDC new_gc = CreateCompatibleDC(gc);
   int save = SaveDC(new_gc);
   SelectObject(new_gc, bitmap);
   BOOL alpha_ok = 0;
   // first try to alpha blend
   if ( can_do_alpha_blending() ) {
-    alpha_ok = fl_alpha_blend(fl_gc, x, y, w, h, new_gc, srcx, srcy, w, h, blendfunc);
+    alpha_ok = fl_alpha_blend(gc, x, y, w, h, new_gc, srcx, srcy, w, h, blendfunc);
   }
   // if that failed (it shouldn't), still copy the bitmap over, but now alpha is 1
   if (!alpha_ok) {
-    BitBlt(fl_gc, x, y, w, h, new_gc, srcx, srcy, SRCCOPY);
+    BitBlt(gc, x, y, w, h, new_gc, srcx, srcy, SRCCOPY);
   }
   RestoreDC(new_gc, save);
   DeleteDC(new_gc);