HiDPI support under WIN32 platform: completed.

git-svn-id: file:///fltk/svn/fltk/branches/branch-1.4@12285 ea41ed52-d2ee-0310-a9c1-e6b18d33e121

10 files changed, 121 insertions, 52 deletions

diff --git a/FL/Fl_Screen_Driver.H b/FL/Fl_Screen_Driver.H
index 9d016043d..7f229e22b 100644
--- a/FL/Fl_Screen_Driver.H
+++ b/FL/Fl_Screen_Driver.H
@@ -167,7 +167,7 @@ public:
   static int scale_handler(int event);
   virtual void init_workarea() {}
   virtual float desktop_scale_factor() {return 1;}
-  float default_scale_factor();
+  void use_startup_scale_factor();
   enum APP_SCALING_CAPABILITY {
     NO_APP_SCALING = 0, ///< The platform does not support rescaling.
     SYSTEMWIDE_APP_SCALING, ///< The platform supports rescaling with the same factor for all screens.
diff --git a/FL/Fl_Window_Driver.H b/FL/Fl_Window_Driver.H
index 20e3503fc..9a588a46e 100644
--- a/FL/Fl_Window_Driver.H
+++ b/FL/Fl_Window_Driver.H
@@ -108,6 +108,8 @@ public:
   void overlay(Fl_Window *o) {
     if (pWindow->as_overlay_window()) pWindow->as_overlay_window()->overlay_ = o;
   }
+  
+  void resize_after_scale_change(int ns, float old_f, float new_f);
 
   // --- window data
   virtual int decorated_w() = 0;
diff --git a/src/Fl_Screen_Driver.cxx b/src/Fl_Screen_Driver.cxx
index 0332f59b3..41cffff03 100644
--- a/src/Fl_Screen_Driver.cxx
+++ b/src/Fl_Screen_Driver.cxx
@@ -364,18 +364,7 @@ void Fl_Screen_Driver::rescale_all_windows_from_screen(int screen, float f)
   }
   for (i = count - 1; i >= 0; i--) { // rescale all top-level windows, finishing with front one
     win = win_array[i];
-    int oldx = win->x(), oldy = win->y();
-    fl_uintptr_t current = win->driver()->current_cursor();
-    win->hide();
-    win->driver()->screen_num(screen);
-    win->position(oldx*old_f/f, oldy*old_f/f);
-    win->driver()->force_position(1);
-    if (win->fullscreen_active()) {
-      win->size(win->w() * old_f/f, win->h() * old_f/f);
-    }
-    win->show();
-    win->driver()->reuse_cursor(current);
-    win->driver()->reuse_icons();
+    win->driver()->resize_after_scale_change(screen, old_f, f);
     win->wait_for_expose();
   }
   delete[] win_array;
@@ -469,21 +458,23 @@ int Fl_Screen_Driver::scale_handler(int event)
 }
 
 
-// determine the scaling value used at startup time (helps supporting HiDPI displays)
-float Fl_Screen_Driver::default_scale_factor()
+// use the startup time scaling value
+void Fl_Screen_Driver::use_startup_scale_factor()
 {
-  float factor = 1;
+  float factor;
   char *p = 0;
   if ((p = fl_getenv("FLTK_SCALING_FACTOR"))) {
     sscanf(p, "%f", &factor);
+    // checks to prevent potential crash (factor <= 0) or very large factors
+    if (factor < 0.25) factor = 0.25;
+    else if (factor > 10.0) factor = 10.0;
   }
   else {
     factor = desktop_scale_factor();
   }
-  // checks to prevent potential crash (factor <= 0) or very large factors
-  if (factor < 0.25) factor = 0.25;
-  else if (factor > 10.0) factor = 10.0;
-  return factor;
+  if (factor) {
+    for (int i = 0; i < screen_count(); i++)  scale(i, factor);
+  }
 }
 
 
@@ -495,10 +486,11 @@ void Fl_Screen_Driver::open_display()
     been_here = true;
     int ns = screen_count();
     if (rescalable()) {
-      float factor = default_scale_factor();
-      for (int i = 0; i < ns; i++) scale(i, factor);
+      use_startup_scale_factor();
       Fl::add_handler(Fl_Screen_Driver::scale_handler);
-      Fl_Graphics_Driver::default_driver().scale(factor);
+      int mx, my;
+      int ns = Fl::screen_driver()->get_mouse(mx, my);
+      Fl_Graphics_Driver::default_driver().scale(scale(ns));
     }
   }
 }
diff --git a/src/Fl_Window_Driver.cxx b/src/Fl_Window_Driver.cxx
index b750b1ff7..2ec0cfaff 100644
--- a/src/Fl_Window_Driver.cxx
+++ b/src/Fl_Window_Driver.cxx
@@ -260,6 +260,23 @@ int Fl_Window_Driver::screen_num() {
   return Fl::screen_num(x(), y(), w(), h());
 }
 
+void Fl_Window_Driver::resize_after_scale_change(int ns, float old_f, float new_f) {
+  int oldx = pWindow->x(), oldy = pWindow->y();
+  fl_uintptr_t current = current_cursor();
+  pWindow->hide();
+  screen_num(ns);
+  pWindow->position(oldx*old_f/new_f, oldy*old_f/new_f);
+  force_position(1);
+  if (pWindow->fullscreen_active()) {
+    pWindow->size(pWindow->w() * old_f/new_f, pWindow->h() * old_f/new_f);
+  }
+  Fl_Graphics_Driver::default_driver().scale(new_f);
+  pWindow->show();
+  reuse_cursor(current);
+  reuse_icons();
+//extern FILE*LOG;fprintf(LOG,"ns=%d old_f%.2f new_f=%.2f\n",ns,old_f,new_f);fflush(LOG);
+}
+
 //
 // End of "$Id$".
 //
diff --git a/src/Fl_win32.cxx b/src/Fl_win32.cxx
index 0366178bc..92a02dd3f 100644
--- a/src/Fl_win32.cxx
+++ b/src/Fl_win32.cxx
@@ -515,24 +515,24 @@ void Fl_WinAPI_Screen_Driver::open_display_platform() {
 }
 
 
-float Fl_WinAPI_Screen_Driver::desktop_scale_factor() {
-  float f = 1;
 #ifdef FLTK_HIDPI_SUPPORT
+void Fl_WinAPI_Screen_Driver::init_screen_scale_factors() {
   typedef HRESULT (WINAPI* GetDpiForMonitor_type)(HMONITOR, int, UINT*, UINT*);
   HMODULE hMod  = LoadLibrary("Shcore.DLL");
   GetDpiForMonitor_type fl_GetDpiForMonitor = NULL;
   if (hMod) fl_GetDpiForMonitor = (GetDpiForMonitor_type)GetProcAddress(hMod, "GetDpiForMonitor");
   if (fl_GetDpiForMonitor) {
-    RECT rect = {0, 0, 0, 0};
-    HMONITOR hm = MonitorFromRect(&rect, MONITOR_DEFAULTTOPRIMARY);
-    UINT dpiX, dpiY;
-    HRESULT r = fl_GetDpiForMonitor(hm, 0, &dpiX, &dpiY);
-    if (r == S_OK) f = dpiX/96.;
-//fprintf(LOG, "result=%d dpiX=%d dpiY=%d factor=%.2f\n", r, dpiX, dpiY, f);fflush(LOG);
+    for (int ns = 0; ns < screen_count(); ns++) {
+      HMONITOR hm = MonitorFromRect(&screens[ns], MONITOR_DEFAULTTONEAREST);
+      UINT dpiX, dpiY;
+      HRESULT r = fl_GetDpiForMonitor(hm, 0, &dpiX, &dpiY);
+      float f = (r == S_OK ? dpiX/96. : 1);
+      scale(ns, f);
+//fprintf(LOG, "desktop_scale_factor ns=%d factor=%.2f\n", ns, f);fflush(LOG);
+    }
   }
-#endif // FLTK_HIDPI_SUPPORT
-  return f;
 }
+#endif // FLTK_HIDPI_SUPPORT
 
 
 class Fl_Win32_At_Exit {
@@ -1111,14 +1111,14 @@ static LRESULT CALLBACK WndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lPar
       
 #ifdef FLTK_HIDPI_SUPPORT
     case 0x02E0: { // WM_DPICHANGED:
-      float f = HIWORD(wParam)/96.;
-      //for now, same scale factor for each screen
-      for (int i = 0; i < Fl::screen_count(); i++) Fl::screen_driver()->scale(i, f);
-      Fl_Graphics_Driver::default_driver().scale(f);
-//fprintf(LOG,"WM_DPICHANGED f=%.2f\n", f);fflush(LOG);
-      if (!window->parent()) {
-        window->hide();
-        window->show();
+      if (!Fl_WinAPI_Window_Driver::data_for_resize_window_between_screens_.busy) {
+        RECT r;
+        float f = HIWORD(wParam)/96.;
+        GetClientRect(hWnd, &r);
+        float old_f = float(r.right)/window->w();
+        int ns = window->driver()->screen_num();
+        Fl::screen_driver()->scale(ns, f);
+        window->driver()->resize_after_scale_change(ns, old_f,  f);
       }
     }
     return 0;
@@ -1446,16 +1446,24 @@ static LRESULT CALLBACK WndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lPar
     if (nx & 0x8000) nx -= 65536;
     if (ny & 0x8000) ny -= 65536;
 //fprintf(LOG,"WM_MOVE position(%d,%d) s=%.2f\n",int(nx/scale),int(ny/scale),scale);
-    window->position(nx/scale, ny/scale);
 // detect when window changes screen
     Fl_WinAPI_Screen_Driver *sd = (Fl_WinAPI_Screen_Driver*)Fl::screen_driver();
-    int news = sd->screen_num_unscaled(nx + window->w()*scale, ny + window->h()*scale);
+    int news = sd->screen_num_unscaled(nx + window->w()*scale/2, ny + window->h()*scale/2);
     Fl_WinAPI_Window_Driver *wd = Fl_WinAPI_Window_Driver::driver(window);
     int olds = wd->screen_num();
+    float s = sd->scale(news);
+//fprintf(LOG,"WM_MOVE olds=%d(%.2f) news=%d(%.2f) busy=%d\n",olds, sd->scale(olds),news, s, Fl_WinAPI_Window_Driver::data_for_resize_window_between_screens_.busy);fflush(LOG);
     if (olds != news) {
-      wd->screen_num(news);
-//fprintf(LOG,"olds=%d news=%d\n",olds,news);
+      if (s != sd->scale(olds) &&
+          !Fl_WinAPI_Window_Driver::data_for_resize_window_between_screens_.busy &&
+          window->user_data() != &Fl_WinAPI_Screen_Driver::transient_scale_display) {
+        Fl_WinAPI_Window_Driver::data_for_resize_window_between_screens_.busy = true;
+        Fl_WinAPI_Window_Driver::data_for_resize_window_between_screens_.screen = news;
+        Fl::add_timeout(1, Fl_WinAPI_Window_Driver::resize_after_screen_change, window);
+      }
+      else if(!Fl_WinAPI_Window_Driver::data_for_resize_window_between_screens_.busy) wd->screen_num(news);
     }
+      window->position(nx/scale, ny/scale);
   }
     break;
 
@@ -1822,8 +1830,12 @@ Fl_X* Fl_WinAPI_Window_Driver::makeWindow() {
     Fl_Window *hint = Fl::first_window();
     if (hint) {
       nscreen = hint->top_window()->driver()->screen_num();
+    } else {
+      int mx, my;
+      nscreen = Fl::screen_driver()->get_mouse(mx, my);
     }
   }
+  w->driver()->screen_num(nscreen);
   float s = Fl::screen_driver()->scale(nscreen);
   int xp = w->x() * s; // these are in graphical units
   int yp = w->y() * s;
@@ -2340,6 +2352,7 @@ int Fl_WinAPI_Window_Driver::set_cursor(const Fl_RGB_Image *image, int hotx, int
 }
 
 void Fl_WinAPI_Window_Driver::reuse_cursor(fl_uintptr_t c) {
+  cursor = (HCURSOR)c;
   SetCursor((HCURSOR)c);
 }
 
diff --git a/src/Fl_x.cxx b/src/Fl_x.cxx
index 71d9d95a6..f81ceff9f 100644
--- a/src/Fl_x.cxx
+++ b/src/Fl_x.cxx
@@ -1252,7 +1252,7 @@ int fl_handle(const XEvent& thisevent)
     XRRUpdateConfiguration_f(&xevent);
     Fl::call_screen_init();
 #if USE_XFT
-    float factor = Fl::screen_driver()->default_scale_factor();
+    float factor = Fl::screen_driver()->desktop_scale_factor();
     for (int screen = 0; screen <= Fl::screen_count(); screen++)
       Fl::screen_driver()->rescale_all_windows_from_screen(screen, factor);
 #endif // USE_XFT
diff --git a/src/drivers/WinAPI/Fl_WinAPI_Screen_Driver.H b/src/drivers/WinAPI/Fl_WinAPI_Screen_Driver.H
index 6dbfa7848..682afca25 100644
--- a/src/drivers/WinAPI/Fl_WinAPI_Screen_Driver.H
+++ b/src/drivers/WinAPI/Fl_WinAPI_Screen_Driver.H
@@ -42,9 +42,14 @@ protected:
   static BOOL CALLBACK screen_cb(HMONITOR mon, HDC, LPRECT r, LPARAM);
   BOOL screen_cb(HMONITOR mon, HDC, LPRECT r);
   int get_mouse_unscaled(int &mx, int &my);
+#ifdef FLTK_HIDPI_SUPPORT
+  void init_screen_scale_factors();
+#endif
 
 public:
-  Fl_WinAPI_Screen_Driver() : Fl_Screen_Driver() { }
+  Fl_WinAPI_Screen_Driver() : Fl_Screen_Driver() {
+    for (int i = 0; i < MAX_SCREENS; i++) scale_of_screen[i] = 1;
+  }
   // --- display management
   virtual int visual(int flags);
   // --- screen configuration
@@ -85,11 +90,17 @@ public:
   virtual void offscreen_size(Fl_Offscreen off, int &width, int &height);
 #if defined(FLTK_HIDPI_SUPPORT)  
   virtual APP_SCALING_CAPABILITY rescalable() {
-    return SYSTEMWIDE_APP_SCALING;
+    return PER_SCREEN_APP_SCALING;
+  }
+#endif
+#if defined(FLTK_HIDPI_SUPPORT)
+  virtual float scale(int n) {
+    return scale_of_screen[n];
+  }
+  virtual void scale(int n, float f) {
+    scale_of_screen[n] = f;
   }
 #endif
-  virtual float scale(int n) {return scale_of_screen[n];}
-  virtual void scale(int n, float f) { scale_of_screen[n] = f;}
   virtual float desktop_scale_factor();
 };
 
diff --git a/src/drivers/WinAPI/Fl_WinAPI_Screen_Driver.cxx b/src/drivers/WinAPI/Fl_WinAPI_Screen_Driver.cxx
index 236a33288..5951ba193 100644
--- a/src/drivers/WinAPI/Fl_WinAPI_Screen_Driver.cxx
+++ b/src/drivers/WinAPI/Fl_WinAPI_Screen_Driver.cxx
@@ -100,7 +100,7 @@ BOOL Fl_WinAPI_Screen_Driver::screen_cb(HMONITOR mon, HDC, LPRECT r)
     screens[num_screens] = mi.rcMonitor;
     // If we also want to record the work area, we would also store mi.rcWork at this point
     work_area[num_screens] = mi.rcWork;
-    scale_of_screen[num_screens] = 1;
+//extern FILE*LOG;fprintf(LOG,"screen_cb ns=%d\n",num_screens);fflush(LOG);
     /*fl_alert("screen %d %d,%d,%d,%d work %d,%d,%d,%d",num_screens,
     screens[num_screens].left,screens[num_screens].right,screens[num_screens].top,screens[num_screens].bottom,
     work_area[num_screens].left,work_area[num_screens].right,work_area[num_screens].top,work_area[num_screens].bottom);
@@ -141,6 +141,9 @@ void Fl_WinAPI_Screen_Driver::init()
         //      NOTE: num_screens is incremented in screen_cb so we must first reset it here...
         num_screens = 0;
         fl_edm(0, 0, screen_cb, (LPARAM)this);
+#ifdef FLTK_HIDPI_SUPPORT
+        init_screen_scale_factors();
+#endif
         return;
       }
     }
@@ -157,6 +160,11 @@ void Fl_WinAPI_Screen_Driver::init()
 }
 
 
+float Fl_WinAPI_Screen_Driver::desktop_scale_factor() {
+  return 0; //indicates each screen has already been assigned its scale factor value
+}
+
+
 void Fl_WinAPI_Screen_Driver::screen_work_area(int &X, int &Y, int &W, int &H, int n)
 {
   if (num_screens < 0) init();
diff --git a/src/drivers/WinAPI/Fl_WinAPI_Window_Driver.H b/src/drivers/WinAPI/Fl_WinAPI_Window_Driver.H
index 7f548c58b..29b20aefc 100644
--- a/src/drivers/WinAPI/Fl_WinAPI_Window_Driver.H
+++ b/src/drivers/WinAPI/Fl_WinAPI_Window_Driver.H
@@ -71,12 +71,17 @@ public:
   static inline Fl_WinAPI_Window_Driver* driver(Fl_Window *w) {return (Fl_WinAPI_Window_Driver*)w->driver();}
   HDC private_dc; // used for OpenGL
   RECT border_width_title_bar_height(int &bx, int &by, int &bt);
-  virtual void screen_num(int n) { screen_num_ = n; }
+  virtual void screen_num(int n);
   virtual int screen_num();
 
   struct icon_data *icon_;
   HCURSOR cursor;
   int custom_cursor;
+  struct type_for_resize_window_between_screens {
+    int screen;
+    bool busy;
+  };
+  static type_for_resize_window_between_screens data_for_resize_window_between_screens_;
   void set_minmax(LPMINMAXINFO minmax);
   int fake_X_wm(int &X, int &Y, int &bt,int &bx,int &by);
   void make_fullscreen(int X, int Y, int W, int H);
@@ -117,6 +122,7 @@ public:
   virtual void capture_titlebar_and_borders(Fl_Shared_Image*& top, Fl_Shared_Image*& left, Fl_Shared_Image*& bottom, Fl_Shared_Image*& right);
   virtual int scroll(int src_x, int src_y, int src_w, int src_h, int dest_x, int dest_y,
                      void (*draw_area)(void*, int,int,int,int), void* data);
+  static void resize_after_screen_change(void *data);
 };
 
 
diff --git a/src/drivers/WinAPI/Fl_WinAPI_Window_Driver.cxx b/src/drivers/WinAPI/Fl_WinAPI_Window_Driver.cxx
index 079ca743d..a5621de6a 100644
--- a/src/drivers/WinAPI/Fl_WinAPI_Window_Driver.cxx
+++ b/src/drivers/WinAPI/Fl_WinAPI_Window_Driver.cxx
@@ -68,6 +68,13 @@ int Fl_WinAPI_Window_Driver::screen_num() {
   return screen_num_ >= 0 ? screen_num_ : 0;
 }
 
+//FILE*LOG=fopen("log.log","w");
+
+void Fl_WinAPI_Window_Driver::screen_num(int n) {
+//fprintf(LOG, "screen_num setter old=%d new=%d\n",screen_num_, n);fflush(LOG);
+  screen_num_ = n;
+}
+
 
 RECT // frame of the decorated window in screen coordinates
   Fl_WinAPI_Window_Driver::border_width_title_bar_height(
@@ -669,6 +676,19 @@ int Fl_WinAPI_Window_Driver::scroll(int src_x, int src_y, int src_w, int src_h,
   return 0;
 }
 
+Fl_WinAPI_Window_Driver::type_for_resize_window_between_screens Fl_WinAPI_Window_Driver::data_for_resize_window_between_screens_ = {0, false};
+
+void Fl_WinAPI_Window_Driver::resize_after_screen_change(void *data) {
+  Fl_Window *win = (Fl_Window*)data;
+  RECT r;
+  GetClientRect(fl_xid(win), &r);
+  float old_f = float(r.right)/win->w();
+  int ns = data_for_resize_window_between_screens_.screen;
+  win->driver()->resize_after_scale_change(ns, old_f, Fl::screen_driver()->scale(ns));
+  win->wait_for_expose();
+  data_for_resize_window_between_screens_.busy = false;
+}
+
 //
 // End of "$Id$".
 //