Fix RTL and complex script title in print preview header/footer.

chrome/renderer/print_web_view_helper.cc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/renderer/print_web_view_helper.h"
 
 #include <string>
 
 #include "base/command_line.h"
 #include "base/logging.h"
@@ skipping 26 matching lines @@
 #include "ui/base/l10n/l10n_util.h"
 #include "webkit/glue/webpreferences.h"
 
 #if defined(OS_POSIX)
 #include "base/process_util.h"
 #endif
 
 #if defined(USE_SKIA)
 #include "skia/ext/vector_canvas.h"
 #include "skia/ext/vector_platform_device_skia.h"
-#include "third_party/skia/include/core/SkTypeface.h"
 #elif defined(OS_MACOSX)
 #include <CoreGraphics/CGContext.h>
 
 #include "base/mac/scoped_cftyperef.h"
 #include "base/sys_string_conversions.h"
 #include "ui/gfx/scoped_cg_context_save_gstate_mac.h"
 #endif
 
 #if defined(OS_MACOSX)
 using base::mac::ScopedCFTypeRef;
@@ skipping 159 matching lines @@
 void PrintHeaderFooterText(
     string16 text,
     WebKit::WebCanvas* canvas,
     HeaderFooterPaint paint,
     float webkit_scale_factor,
     const PageSizeMargins& page_layout,
     printing::HorizontalHeaderFooterPosition horizontal_position,
     printing::VerticalHeaderFooterPosition vertical_position,
     double offset_to_baseline) {
 #if defined(USE_SKIA)
-  size_t text_byte_length = text.length() * sizeof(char16);
-  double text_width_in_points = SkScalarToDouble(paint.measureText(
-      text.c_str(), text_byte_length));
-  SkPoint point = GetHeaderFooterPosition(webkit_scale_factor, page_layout,
-                                          horizontal_position,
-                                          vertical_position, offset_to_baseline,
-                                          text_width_in_points);
-  paint.setTextSize(SkDoubleToScalar(
-      paint.getTextSize() / webkit_scale_factor));
-  canvas->drawText(text.c_str(), text_byte_length, point.x(), point.y(),
-                   paint);
+  // Convert text to glyphs first.
+  std::vector<uint16_t> glyphs;

[jungshik at Google, 2012/01/06 22:38:45]

Just using an array of glyphs does not work well because the glyph position is
also critical. Moreover, the input string may not be rendered with a single
font. In that case, each glyph id has to be associated with a font as well. 

As you wrote offline, I think using RenderText is a way to go (after resolving
issues you came across while trying to use it). 

+  if (!PrintWebViewHelper::ConvertTextToGlyphs(paint.getTypeface(),
+      text, &glyphs)) {
+    // Conversion failed, fall back to draw text.
+    size_t text_byte_length = text.length() * sizeof(char16);
+    double text_width_in_points = SkScalarToDouble(paint.measureText(
+        text.c_str(), text_byte_length));
+    SkPoint point = GetHeaderFooterPosition(webkit_scale_factor, page_layout,
+                                            horizontal_position,
+                                            vertical_position,
+                                            offset_to_baseline,
+                                            text_width_in_points);
+    paint.setTextSize(SkDoubleToScalar(
+        paint.getTextSize() / webkit_scale_factor));
+    canvas->drawText(text.c_str(), text_byte_length, point.x(), point.y(),
+                     paint);
+  } else {
+    paint.setTextEncoding(SkPaint::kGlyphID_TextEncoding);
+    size_t glyphs_byte_length = glyphs.size() * sizeof(uint16_t);
+    double text_width_in_points = SkScalarToDouble(paint.measureText(
+        &glyphs[0], glyphs_byte_length));
+    SkPoint point = GetHeaderFooterPosition(webkit_scale_factor, page_layout,
+                                            horizontal_position,
+                                            vertical_position,
+                                            offset_to_baseline,
+                                            text_width_in_points);
+    paint.setTextSize(SkDoubleToScalar(
+        paint.getTextSize() / webkit_scale_factor));
+    canvas->drawText(&glyphs[0], glyphs_byte_length, point.x(), point.y(),
+                     paint);
+  }
 #elif defined(OS_MACOSX)
   ScopedCFTypeRef<CFStringRef> cf_text(base::SysUTF16ToCFStringRef(text));
   ScopedCFTypeRef<CFAttributedStringRef> cf_attr_text(
       CFAttributedStringCreate(NULL, cf_text, paint));
   ScopedCFTypeRef<CTLineRef> line(CTLineCreateWithAttributedString(
       cf_attr_text));
   double text_width_in_points =
       CTLineGetTypographicBounds(line, NULL, NULL, NULL) * webkit_scale_factor;
   SkPoint point = GetHeaderFooterPosition(webkit_scale_factor,
                                           page_layout, horizontal_position,
@@ skipping 1309 matching lines @@
   DCHECK(IsRendering());
   return prep_frame_view_->GetPrintCanvasSize();
 }
 
 void PrintWebViewHelper::PrintPreviewContext::ClearContext() {
   prep_frame_view_.reset();
   metafile_.reset();
   pages_to_render_.clear();
   error_ = PREVIEW_ERROR_NONE;
 }