master 726969a4b4: Remove flickering when toggling between different fullscreen states on Haiku

[Po Lu]

branch: master
commit 726969a4b4e3e0f298b95a04d23e7a131d7abec7
Author: Po Lu <luangruo@yahoo.com>
Commit: Po Lu <luangruo@yahoo.com>

    Remove flickering when toggling between different fullscreen states on Haiku
    
    * src/haiku_support.cc (FrameMoved): Don't allow moving the
    frame along the "filled" axis when fullwidth or fullheight.
    (ClearFullscreen): New argument `mode'.  Return the previous
    rect but don't revert the frame to it if the target mode is not
    NONE.
    (SetFullscreen): Use rect provided by ClearFullscreen instead.
---
 src/haiku_support.cc | 53 ++++++++++++++++++++++++++++++++++++++--------------
 1 file changed, 39 insertions(+), 14 deletions(-)

diff --git a/src/haiku_support.cc b/src/haiku_support.cc
index 0b3ab4cf4a..3961d33e4d 100644
--- a/src/haiku_support.cc
+++ b/src/haiku_support.cc
@@ -1042,6 +1042,20 @@ public:
     BRect frame, decorator_frame;
     struct child_frame *f;
 
+    if (fullscreen_mode == FULLSCREEN_MODE_WIDTH
+       && new_position.x != 0)
+      {
+       MoveTo (0, new_position.y);
+       return;
+      }
+
+    if (fullscreen_mode == FULLSCREEN_MODE_HEIGHT
+       && new_position.y != 0)
+      {
+       MoveTo (new_position.x, 0);
+       return;
+      }
+
     rq.window = this;
     rq.x = std::lrint (new_position.x);
     rq.y = std::lrint (new_position.y);
@@ -1159,34 +1173,46 @@ public:
     child_frame_lock.Unlock ();
   }
 
-  void
-  ClearFullscreen (void)
+  BRect
+  ClearFullscreen (enum haiku_fullscreen_mode target_mode)
   {
+    BRect original_frame;
+
     switch (fullscreen_mode)
       {
       case FULLSCREEN_MODE_MAXIMIZED:
-       BWindow::Zoom (pre_zoom_rect.LeftTop (),
-                      BE_RECT_WIDTH (pre_zoom_rect) - 1,
-                      BE_RECT_HEIGHT (pre_zoom_rect) - 1);
+       original_frame = pre_zoom_rect;
+
+       if (target_mode == FULLSCREEN_MODE_NONE)
+         BWindow::Zoom (pre_zoom_rect.LeftTop (),
+                        BE_RECT_WIDTH (pre_zoom_rect) - 1,
+                        BE_RECT_HEIGHT (pre_zoom_rect) - 1);
        break;
 
       case FULLSCREEN_MODE_BOTH:
       case FULLSCREEN_MODE_HEIGHT:
       case FULLSCREEN_MODE_WIDTH:
-       MoveTo (pre_fullscreen_rect.LeftTop ());
-       ResizeTo (BE_RECT_WIDTH (pre_fullscreen_rect) - 1,
-                 BE_RECT_HEIGHT (pre_fullscreen_rect) - 1);
-
+       original_frame = pre_fullscreen_rect;
        SetFlags (Flags () & ~(B_NOT_MOVABLE
                               | B_NOT_ZOOMABLE
                               | B_NOT_RESIZABLE));
+
+       if (target_mode != FULLSCREEN_MODE_NONE)
+         goto out;
+
+       MoveTo (pre_fullscreen_rect.LeftTop ());
+       ResizeTo (BE_RECT_WIDTH (pre_fullscreen_rect) - 1,
+                 BE_RECT_HEIGHT (pre_fullscreen_rect) - 1);
        break;
 
       case FULLSCREEN_MODE_NONE:
+       original_frame = Frame ();
        break;
       }
 
+  out:
     fullscreen_mode = FULLSCREEN_MODE_NONE;
+    return original_frame;
   }
 
   BRect
@@ -1211,17 +1237,17 @@ public:
   void
   SetFullscreen (enum haiku_fullscreen_mode mode)
   {
-    BRect zoom_rect;
+    BRect zoom_rect, frame;
 
     if (fullscreen_mode == mode)
       return;
 
-    ClearFullscreen ();
+    frame = ClearFullscreen (mode);
 
     switch (mode)
       {
       case FULLSCREEN_MODE_MAXIMIZED:
-       pre_zoom_rect = Frame ();
+       pre_zoom_rect = frame;
        zoom_rect = CalculateZoomRect ();
        BWindow::Zoom (zoom_rect.LeftTop (),
                       BE_RECT_WIDTH (zoom_rect) - 1,
@@ -1235,12 +1261,11 @@ public:
       case FULLSCREEN_MODE_HEIGHT:
       case FULLSCREEN_MODE_WIDTH:
        SetFlags (Flags () | B_NOT_ZOOMABLE | B_NOT_RESIZABLE);
-       pre_fullscreen_rect = Frame ();
+       pre_fullscreen_rect = frame;
        zoom_rect = FullscreenRectForMode (mode);
        ResizeTo (BE_RECT_WIDTH (zoom_rect) - 1,
                  BE_RECT_HEIGHT (zoom_rect) - 1);
        MoveTo (zoom_rect.left, zoom_rect.top);
-
        break;
 
       case FULLSCREEN_MODE_NONE: