Refactor [FramedBrowserWindow drawWindowThemeInDirtyRect:] to use themeImagePositionForAlignment:

chrome/browser/ui/cocoa/framed_browser_window.mm

Index: chrome/browser/ui/cocoa/framed_browser_window.mm
diff --git a/chrome/browser/ui/cocoa/framed_browser_window.mm b/chrome/browser/ui/cocoa/framed_browser_window.mm
index d53bd302967ae65bd435441d05bd03dc8a0dd963..68238e1e717977610fb38f06fec96c10a60dffc2 100644
--- a/chrome/browser/ui/cocoa/framed_browser_window.mm
+++ b/chrome/browser/ui/cocoa/framed_browser_window.mm
@@ -8,6 +8,7 @@
 #include "chrome/browser/global_keyboard_shortcuts_mac.h"
 #include "chrome/browser/profiles/profile_info_util.h"
 #import "chrome/browser/ui/cocoa/browser_window_controller.h"
+#import "chrome/browser/ui/cocoa/browser_window_utils.h"
 #import "chrome/browser/ui/cocoa/custom_frame_view.h"
 #import "chrome/browser/ui/cocoa/nsview_additions.h"
 #import "chrome/browser/ui/cocoa/tabs/tab_strip_controller.h"
@@ -15,6 +16,7 @@
 #include "chrome/browser/themes/theme_properties.h"
 #include "chrome/browser/themes/theme_service.h"
 #include "grit/theme_resources.h"
+#include "ui/base/cocoa/nsgraphics_context_additions.h"
 
 // Replicate specific 10.7 SDK declarations for building with prior SDKs.
 #if !defined(MAC_OS_X_VERSION_10_7) || \
@@ -42,7 +44,6 @@ enum {
 namespace {
 
 const CGFloat kBrowserFrameViewPaintHeight = 60.0;
-const NSPoint kBrowserFrameViewPatternPhaseOffset = { -5, 3 };
 
 // Size of the gradient. Empirically determined so that the gradient looks
 // like what the heuristic does when there are just a few tabs.
@@ -361,7 +362,6 @@ const CGFloat kWindowGradientHeight = 24.0;
       drawWindowThemeInDirtyRect:rect
                          forView:view
                           bounds:windowRect
-                          offset:NSZeroPoint
             forceBlackBackground:NO];
 
   // If the window needs a title and we painted over the title as drawn by the
@@ -394,7 +394,6 @@ const CGFloat kWindowGradientHeight = 24.0;
 + (BOOL)drawWindowThemeInDirtyRect:(NSRect)dirtyRect
                            forView:(NSView*)view
                             bounds:(NSRect)bounds
-                            offset:(NSPoint)offset
               forceBlackBackground:(BOOL)forceBlackBackground {
   ui::ThemeProvider* themeProvider = [[view window] themeProvider];
   if (!themeProvider)
@@ -435,31 +434,6 @@ const CGFloat kWindowGradientHeight = 24.0;
 
   BOOL themed = NO;
   if (themeImageColor) {
-    // The titlebar/tabstrip header on the mac is slightly smaller than on
-    // Windows.  To keep the window background lined up with the tab and toolbar
-    // patterns, we have to shift the pattern slightly, rather than simply
-    // drawing it from the top left corner.  The offset below was empirically
-    // determined in order to line these patterns up.
-    //
-    // This will make the themes look slightly different than in Windows/Linux
-    // because of the differing heights between window top and tab top, but this
-    // has been approved by UI.
-    NSView* frameView = [[[view window] contentView] superview];
-    NSPoint topLeft = NSMakePoint(NSMinX(bounds), NSMaxY(bounds));
-    NSPoint topLeftInFrameCoordinates =
-        [view convertPoint:topLeft toView:frameView];
-
-    NSPoint phase = kBrowserFrameViewPatternPhaseOffset;
-    phase.x += (offset.x + topLeftInFrameCoordinates.x);
-    phase.y += (offset.y + topLeftInFrameCoordinates.y);
-
-    // Align the phase to physical pixels so resizing the window under HiDPI
-    // doesn't cause wiggling of the theme.
-    phase = [frameView convertPointToBase:phase];
-    phase.x = floor(phase.x);
-    phase.y = floor(phase.y);
-    phase = [frameView convertPointFromBase:phase];
-
     // Default to replacing any existing pixels with the theme image, but if
     // asked paint black first and blend the theme with black.
     NSCompositingOperation operation = NSCompositeCopy;
@@ -469,7 +443,19 @@ const CGFloat kWindowGradientHeight = 24.0;
       operation = NSCompositeSourceOver;
     }
 
-    [[NSGraphicsContext currentContext] setPatternPhase:phase];
+    NSPoint position = [[view window] themeImagePositionForAlignment:
+        THEME_IMAGE_ALIGN_WITH_FRAME];
+
+    // Align the phase to physical pixels so resizing the window under HiDPI
+    // doesn't cause wiggling of the theme.
+    NSView* frameView = [[[view window] contentView] superview];

[pkotwicz, 2013/07/21 23:10:29]

I assume that we probably want to move the logic below to
themeImagePositionForAlignment: However I do not have a retina mac to figure out
if we have a problems with the toolbar image etc.

[Nico, 2013/07/22 04:18:01]

You can run retina mode on regular macs:
http://developer.apple.com/library/mac/#documentation/GraphicsAnimation/Conce...

(open the "To enable high-resolution display modes" section)

[pkotwicz, 2013/07/22 21:23:30]

I did not notice anything wiggling with the toolbar images in retina (2x) mode.
So we do not need to generalize.
The code below seems to have been added to support non integer scale factors.
https://codereview.chromium.org/879003

I have not checked fractional scale factors. That seems to be for another day.
http://devimages.apple.com/maintenance

+    position = [frameView convertPointToBase:position];
+    position.x = floor(position.x);
+    position.y = floor(position.y);
+    position = [frameView convertPointFromBase:position];
+    [[NSGraphicsContext currentContext] cr_setPatternPhase:position
+                                                   forView:view];
+
     [themeImageColor set];
     NSRectFillUsingOperation(dirtyRect, operation);
     themed = YES;
@@ -493,11 +479,14 @@ const CGFloat kWindowGradientHeight = 24.0;
 
   if (overlayImage) {
     // Anchor to top-left and don't scale.
+    NSView* frameView = [[[view window] contentView] superview];
+    NSPoint position = [[view window] themeImagePositionForAlignment:
+        THEME_IMAGE_ALIGN_WITH_FRAME];
+    position = [view convertPoint:position fromView:frameView];
     NSSize overlaySize = [overlayImage size];
     NSRect imageFrame = NSMakeRect(0, 0, overlaySize.width, overlaySize.height);
-    [overlayImage drawAtPoint:NSMakePoint(offset.x,
-                                          NSHeight(bounds) + offset.y -
-                                               overlaySize.height)
+    [overlayImage drawAtPoint:NSMakePoint(position.x,
+                                          position.y - overlaySize.height)
                      fromRect:imageFrame
                     operation:NSCompositeSourceOver
                      fraction:1.0];