Specify clip rects when drawing Mac native widgets

Source/platform/mac/ThemeMac.mm

 /*
  * Copyright (C) 2008, 2010, 2011, 2012 Apple Inc. All Rights Reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 73 matching lines @@
     if ([[self familyName] hasPrefix:@"."])
         return [self fontName];
 
     return [self familyName];
 }
 
 @end
 
 namespace blink {
 
-enum {
-    topMargin,
-    rightMargin,
-    bottomMargin,
-    leftMargin
-};
-
 Theme* platformTheme()
 {
     DEFINE_STATIC_LOCAL(ThemeMac, themeMac, ());
     return &themeMac;
 }
 
 // Helper functions used by a bunch of different control parts.
 
 static NSControlSize controlSizeForFont(const FontDescription& fontDescription)
 {
@@ skipping 86 matching lines @@
 
     // Do not process PressedState if !EnabledControlState or ReadOnlyControlState.
     if (states & PressedControlState) {
         if (kind == kThemeIncDecButton || kind == kThemeIncDecButtonSmall || kind == kThemeIncDecButtonMini)
             return states & SpinUpControlState ? kThemeStatePressedUp : kThemeStatePressedDown;
         return kThemeStatePressed;
     }
     return kThemeStateActive;
 }
 
-static IntRect inflateRect(const IntRect& zoomedRect, const IntSize& zoomedSize, const int* margins, float zoomFactor)
+// static
+IntRect ThemeMac::inflateRect(const IntRect& zoomedRect, const IntSize& zoomedSize, const int* margins, float zoomFactor)
 {
     // Only do the inflation if the available width/height are too small.  Otherwise try to
     // fit the glow/check space into the available box's width/height.
-    int widthDelta = zoomedRect.width() - (zoomedSize.width() + margins[leftMargin] * zoomFactor + margins[rightMargin] * zoomFactor);
-    int heightDelta = zoomedRect.height() - (zoomedSize.height() + margins[topMargin] * zoomFactor + margins[bottomMargin] * zoomFactor);
+    int widthDelta = zoomedRect.width() - (zoomedSize.width() + margins[LeftMargin] * zoomFactor + margins[RightMargin] * zoomFactor);
+    int heightDelta = zoomedRect.height() - (zoomedSize.height() + margins[TopMargin] * zoomFactor + margins[BottomMargin] * zoomFactor);
     IntRect result(zoomedRect);
     if (widthDelta < 0) {
-        result.setX(result.x() - margins[leftMargin] * zoomFactor);
+        result.setX(result.x() - margins[LeftMargin] * zoomFactor);
         result.setWidth(result.width() - widthDelta);
     }
     if (heightDelta < 0) {
-        result.setY(result.y() - margins[topMargin] * zoomFactor);
+        result.setY(result.y() - margins[TopMargin] * zoomFactor);
         result.setHeight(result.height() - heightDelta);
     }
     return result;
 }
 
+// static
+IntRect ThemeMac::inflateRectForFocusRing(const IntRect& rect) {
+#if BUTTON_CELL_DRAW_WITH_FRAME_DRAWS_FOCUS_RING
+    // Just put a margin of 16 units around the rect. The UI elements that use this don't appropriately
+    // scale their focus rings appropriately (e.g, paint pickers), or switch to non-native widgets when
+    // scaled (e.g, check boxes and radio buttons).
+    const int margin = 16;
+    IntRect result;
+    result.setX(rect.x() - margin);
+    result.setY(rect.y() - margin);
+    result.setWidth(rect.width() + 2 * margin);
+    result.setHeight(rect.height() + 2 * margin);
+    return result;
+#else
+    return rect;
+#endif
+}
+
 // Checkboxes
 
 static const IntSize* checkboxSizes()
 {
     static const IntSize sizes[3] = { IntSize(14, 14), IntSize(12, 12), IntSize(10, 10) };
     return sizes;
 }
 
 static const int* checkboxMargins(NSControlSize controlSize)
 {
@@ skipping 42 matching lines @@
     BEGIN_BLOCK_OBJC_EXCEPTIONS
 
     // Determine the width and height needed for the control and prepare the cell for painting.
     NSButtonCell *checkboxCell = checkbox(states, zoomedRect, zoomFactor);
     GraphicsContextStateSaver stateSaver(*context);
 
     NSControlSize controlSize = [checkboxCell controlSize];
     IntSize zoomedSize = checkboxSizes()[controlSize];
     zoomedSize.setWidth(zoomedSize.width() * zoomFactor);
     zoomedSize.setHeight(zoomedSize.height() * zoomFactor);
-    IntRect inflatedRect = inflateRect(zoomedRect, zoomedSize, checkboxMargins(controlSize), zoomFactor);
+    IntRect inflatedRect = ThemeMac::inflateRect(zoomedRect, zoomedSize, checkboxMargins(controlSize), zoomFactor);
     
     if (zoomFactor != 1.0f) {
         inflatedRect.setWidth(inflatedRect.width() / zoomFactor);
         inflatedRect.setHeight(inflatedRect.height() / zoomFactor);
         context->translate(inflatedRect.x(), inflatedRect.y());
         context->scale(zoomFactor, zoomFactor);
         context->translate(-inflatedRect.x(), -inflatedRect.y());
     }
 
-    LocalCurrentGraphicsContext localContext(context);
+    LocalCurrentGraphicsContext localContext(context, ThemeMac::inflateRectForFocusRing(inflatedRect));
     NSView *view = ThemeMac::ensuredView(scrollView);
     [checkboxCell drawWithFrame:NSRect(inflatedRect) inView:view];
 #if !BUTTON_CELL_DRAW_WITH_FRAME_DRAWS_FOCUS_RING
     if (states & FocusControlState)
         [checkboxCell _web_drawFocusRingWithFrame:NSRect(inflatedRect) inView:view];
 #endif
     [checkboxCell setControlView:nil];
     
     END_BLOCK_OBJC_EXCEPTIONS
 }
@@ skipping 49 matching lines @@
 static void paintRadio(ControlStates states, GraphicsContext* context, const IntRect& zoomedRect, float zoomFactor, ScrollView* scrollView)
 {
     // Determine the width and height needed for the control and prepare the cell for painting.
     NSButtonCell *radioCell = radio(states, zoomedRect, zoomFactor);
     GraphicsContextStateSaver stateSaver(*context);
 
     NSControlSize controlSize = [radioCell controlSize];
     IntSize zoomedSize = radioSizes()[controlSize];
     zoomedSize.setWidth(zoomedSize.width() * zoomFactor);
     zoomedSize.setHeight(zoomedSize.height() * zoomFactor);
-    IntRect inflatedRect = inflateRect(zoomedRect, zoomedSize, radioMargins(controlSize), zoomFactor);
+    IntRect inflatedRect = ThemeMac::inflateRect(zoomedRect, zoomedSize, radioMargins(controlSize), zoomFactor);
     
     if (zoomFactor != 1.0f) {
         inflatedRect.setWidth(inflatedRect.width() / zoomFactor);
         inflatedRect.setHeight(inflatedRect.height() / zoomFactor);
         context->translate(inflatedRect.x(), inflatedRect.y());
         context->scale(zoomFactor, zoomFactor);
         context->translate(-inflatedRect.x(), -inflatedRect.y());
     }
 
-    LocalCurrentGraphicsContext localContext(context);
+    LocalCurrentGraphicsContext localContext(context, ThemeMac::inflateRectForFocusRing(inflatedRect));
     BEGIN_BLOCK_OBJC_EXCEPTIONS
     NSView *view = ThemeMac::ensuredView(scrollView);
     [radioCell drawWithFrame:NSRect(inflatedRect) inView:view];
 #if !BUTTON_CELL_DRAW_WITH_FRAME_DRAWS_FOCUS_RING
     if (states & FocusControlState)
         [radioCell _web_drawFocusRingWithFrame:NSRect(inflatedRect) inView:view];
 #endif
     [radioCell setControlView:nil];
     END_BLOCK_OBJC_EXCEPTIONS
 }
@@ skipping 61 matching lines @@
     zoomedSize.setHeight(zoomedSize.height() * zoomFactor);
     IntRect inflatedRect = zoomedRect;
     if ([buttonCell bezelStyle] == NSRoundedBezelStyle) {
         // Center the button within the available space.
         if (inflatedRect.height() > zoomedSize.height()) {
             inflatedRect.setY(inflatedRect.y() + (inflatedRect.height() - zoomedSize.height()) / 2);
             inflatedRect.setHeight(zoomedSize.height());
         }
 
         // Now inflate it to account for the shadow.
-        inflatedRect = inflateRect(inflatedRect, zoomedSize, buttonMargins(controlSize), zoomFactor);
+        inflatedRect = ThemeMac::inflateRect(inflatedRect, zoomedSize, buttonMargins(controlSize), zoomFactor);
 
         if (zoomFactor != 1.0f) {
             inflatedRect.setWidth(inflatedRect.width() / zoomFactor);
             inflatedRect.setHeight(inflatedRect.height() / zoomFactor);
             context->translate(inflatedRect.x(), inflatedRect.y());
             context->scale(zoomFactor, zoomFactor);
             context->translate(-inflatedRect.x(), -inflatedRect.y());
         }
     } 
 
-    LocalCurrentGraphicsContext localContext(context);
+    LocalCurrentGraphicsContext localContext(context, ThemeMac::inflateRectForFocusRing(inflatedRect));
     NSView *view = ThemeMac::ensuredView(scrollView);
 
     [buttonCell drawWithFrame:NSRect(inflatedRect) inView:view];
 #if !BUTTON_CELL_DRAW_WITH_FRAME_DRAWS_FOCUS_RING
     if (states & FocusControlState)
         [buttonCell _web_drawFocusRingWithFrame:NSRect(inflatedRect) inView:view];
 #endif
     [buttonCell setControlView:nil];
 
     END_BLOCK_OBJC_EXCEPTIONS
@@ skipping 48 matching lines @@
     CGRect bounds(rect);
     CGRect backgroundBounds;
     HIThemeGetButtonBackgroundBounds(&bounds, &drawInfo, &backgroundBounds);
     // Center the stepper rectangle in the specified area.
     backgroundBounds.origin.x = bounds.origin.x + (bounds.size.width - backgroundBounds.size.width) / 2;
     if (backgroundBounds.size.height < bounds.size.height) {
         int heightDiff = clampToInteger(bounds.size.height - backgroundBounds.size.height);
         backgroundBounds.origin.y = bounds.origin.y + (heightDiff / 2) + 1;
     }
 
-    LocalCurrentGraphicsContext localContext(context);
+    LocalCurrentGraphicsContext localContext(context, rect);
     HIThemeDrawButton(&backgroundBounds, &drawInfo, localContext.cgContext(), kHIThemeOrientationNormal, 0);
 }
 
 // This will ensure that we always return a valid NSView, even if ScrollView doesn't have an associated document NSView.
 // If the ScrollView doesn't have an NSView, we will return a fake NSView whose sole purpose is to tell AppKit that it's flipped.
 NSView *ThemeMac::ensuredView(ScrollView* scrollView)
 {
 
     // Use a fake flipped view.
     static NSView *flippedView = [[WebCoreFlippedView alloc] init];
@@ skipping 169 matching lines @@
             break;
         case InnerSpinButtonPart:
             paintStepper(states, context, zoomedRect, zoomFactor, scrollView);
             break;
         default:
             break;
     }
 }
 
 }