draw only when needed

1 files changed, 40 insertions, 37 deletions

diff --git a/src/buttonwidget.cc b/src/buttonwidget.cc
index efb98e76..390e5948 100644
--- a/src/buttonwidget.cc
+++ b/src/buttonwidget.cc
@@ -81,49 +81,52 @@ void OBButtonWidget::update()
 {
   otk::PixmapMask *pm;
   int width;
+  bool draw = _dirty;
 
   otk::OtkWidget::update();
 
-  switch (type()) {
-  case Type_StickyButton:
-    pm = _style->getStickyButtonMask();
-    break;
-  case Type_CloseButton:
-    pm = _style->getCloseButtonMask();
-    break;
-  case Type_MaximizeButton:
-    pm = _style->getMaximizeButtonMask();
-    break;
-  case Type_IconifyButton:
-    pm = _style->getIconifyButtonMask();
-    break;
-  case Type_LeftGrip:
-  case Type_RightGrip:
-    return; // no drawing
-  default:
-    assert(false); // there's no other button widgets!
-  }
+  if (draw) {
+    switch (type()) {
+    case Type_StickyButton:
+      pm = _style->getStickyButtonMask();
+      break;
+    case Type_CloseButton:
+      pm = _style->getCloseButtonMask();
+      break;
+    case Type_MaximizeButton:
+      pm = _style->getMaximizeButtonMask();
+      break;
+    case Type_IconifyButton:
+      pm = _style->getIconifyButtonMask();
+      break;
+    case Type_LeftGrip:
+    case Type_RightGrip:
+      return; // no drawing
+    default:
+      assert(false); // there's no other button widgets!
+    }
 
-  if (pm->mask == None) return; // no mask for the button, leave it empty
+    if (pm->mask == None) return; // no mask for the button, leave it empty
 
-  width = _rect.width();
+    width = _rect.width();
   
-  otk::BPen pen(_focused ? *_style->getButtonPicFocus() :
-                           *_style->getButtonPicUnfocus());
-
-  // set the clip region
-  XSetClipMask(otk::OBDisplay::display, pen.gc(), pm->mask);
-  XSetClipOrigin(otk::OBDisplay::display, pen.gc(),
-                 (width - pm->w)/2, (width - pm->h)/2);
-
-  // fill in the clipped region
-  XFillRectangle(otk::OBDisplay::display, _window, pen.gc(),
-                 (width - pm->w)/2, (width - pm->h)/2,
-                 (width + pm->w)/2, (width + pm->h)/2);
-
-  // unset the clip region
-  XSetClipMask(otk::OBDisplay::display, pen.gc(), None);
-  XSetClipOrigin(otk::OBDisplay::display, pen.gc(), 0, 0);
+    otk::BPen pen(_focused ? *_style->getButtonPicFocus() :
+                  *_style->getButtonPicUnfocus());
+
+    // set the clip region
+    XSetClipMask(otk::OBDisplay::display, pen.gc(), pm->mask);
+    XSetClipOrigin(otk::OBDisplay::display, pen.gc(),
+                   (width - pm->w)/2, (width - pm->h)/2);
+
+    // fill in the clipped region
+    XFillRectangle(otk::OBDisplay::display, _window, pen.gc(),
+                   (width - pm->w)/2, (width - pm->h)/2,
+                   (width + pm->w)/2, (width + pm->h)/2);
+
+    // unset the clip region
+    XSetClipMask(otk::OBDisplay::display, pen.gc(), None);
+    XSetClipOrigin(otk::OBDisplay::display, pen.gc(), 0, 0);
+  }
 }