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      1 /*
      2  * Copyright (C) 2012 Google Inc.  All rights reserved.
      3  *
      4  * Redistribution and use in source and binary forms, with or without
      5  * modification, are permitted provided that the following conditions
      6  * are met:
      7  * 1. Redistributions of source code must retain the above copyright
      8  *    notice, this list of conditions and the following disclaimer.
      9  * 2. Redistributions in binary form must reproduce the above copyright
     10  *    notice, this list of conditions and the following disclaimer in the
     11  *    documentation and/or other materials provided with the distribution.
     12  *
     13  * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
     14  * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     16  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
     17  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
     18  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
     19  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
     20  * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
     21  * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     22  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
     23  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     24  */
     25 
     26 #include "config.h"
     27 #include "core/rendering/RenderThemeChromiumFontProvider.h"
     28 
     29 #include <windows.h>
     30 
     31 #include "CSSValueKeywords.h"
     32 #include "core/platform/graphics/FontDescription.h"
     33 #include "core/platform/win/HWndDC.h"
     34 #include "core/platform/win/SystemInfo.h"
     35 #include "wtf/text/WTFString.h"
     36 
     37 #define SIZEOF_STRUCT_WITH_SPECIFIED_LAST_MEMBER(structName, member) \
     38     offsetof(structName, member) + \
     39     (sizeof static_cast<structName*>(0)->member)
     40 #define NONCLIENTMETRICS_SIZE_PRE_VISTA \
     41     SIZEOF_STRUCT_WITH_SPECIFIED_LAST_MEMBER(NONCLIENTMETRICS, lfMessageFont)
     42 
     43 namespace WebCore {
     44 
     45 static FontDescription& smallSystemFont()
     46 {
     47     DEFINE_STATIC_LOCAL(FontDescription, font, ());
     48     return font;
     49 }
     50 
     51 static FontDescription& menuFont()
     52 {
     53     DEFINE_STATIC_LOCAL(FontDescription, font, ());
     54     return font;
     55 }
     56 
     57 static FontDescription& labelFont()
     58 {
     59     DEFINE_STATIC_LOCAL(FontDescription, font, ());
     60     return font;
     61 }
     62 
     63 // Converts |points| to pixels. One point is 1/72 of an inch.
     64 static float pointsToPixels(float points)
     65 {
     66     static float pixelsPerInch = 0.0f;
     67     if (!pixelsPerInch) {
     68         HWndDC hdc(0); // What about printing? Is this the right DC?
     69         if (hdc) // Can this ever actually be 0?
     70             pixelsPerInch = GetDeviceCaps(hdc, LOGPIXELSY);
     71         else
     72             pixelsPerInch = 96.0f;
     73     }
     74 
     75     static const float pointsPerInch = 72.0f;
     76     return points / pointsPerInch * pixelsPerInch;
     77 }
     78 
     79 static void getNonClientMetrics(NONCLIENTMETRICS* metrics)
     80 {
     81     static UINT size = (windowsVersion() >= WindowsVista) ?
     82         sizeof(NONCLIENTMETRICS) : NONCLIENTMETRICS_SIZE_PRE_VISTA;
     83     metrics->cbSize = size;
     84     bool success = !!SystemParametersInfo(SPI_GETNONCLIENTMETRICS, size, metrics, 0);
     85     ASSERT(success);
     86 }
     87 
     88 // Return the height of system font |font| in pixels. We use this size by
     89 // default for some non-form-control elements.
     90 static float systemFontSize(const LOGFONT& font)
     91 {
     92     float size = -font.lfHeight;
     93     if (size < 0) {
     94         HFONT hFont = CreateFontIndirect(&font);
     95         if (hFont) {
     96             HWndDC hdc(0); // What about printing? Is this the right DC?
     97             if (hdc) {
     98                 HGDIOBJ hObject = SelectObject(hdc, hFont);
     99                 TEXTMETRIC tm;
    100                 GetTextMetrics(hdc, &tm);
    101                 SelectObject(hdc, hObject);
    102                 size = tm.tmAscent;
    103             }
    104             DeleteObject(hFont);
    105         }
    106     }
    107 
    108     // The "codepage 936" bit here is from Gecko; apparently this helps make
    109     // fonts more legible in Simplified Chinese where the default font size is
    110     // too small.
    111     //
    112     // FIXME: http://b/1119883 Since this is only used for "small caption",
    113     // "menu", and "status bar" objects, I'm not sure how much this even
    114     // matters. Plus the Gecko patch went in back in 2002, and maybe this
    115     // isn't even relevant anymore. We should investigate whether this should
    116     // be removed, or perhaps broadened to be "any CJK locale".
    117     //
    118     return ((size < 12.0f) && (GetACP() == 936)) ? 12.0f : size;
    119 }
    120 
    121 // static
    122 void RenderThemeChromiumFontProvider::systemFont(CSSValueID valueID, FontDescription& fontDescription)
    123 {
    124     // This logic owes much to RenderThemeSafari.cpp.
    125     FontDescription* cachedDesc = 0;
    126     AtomicString faceName;
    127     float fontSize = 0;
    128     switch (valueID) {
    129     case CSSValueSmallCaption:
    130         cachedDesc = &smallSystemFont();
    131         if (!smallSystemFont().isAbsoluteSize()) {
    132             NONCLIENTMETRICS metrics;
    133             getNonClientMetrics(&metrics);
    134             faceName = AtomicString(metrics.lfSmCaptionFont.lfFaceName, wcslen(metrics.lfSmCaptionFont.lfFaceName));
    135             fontSize = systemFontSize(metrics.lfSmCaptionFont);
    136         }
    137         break;
    138     case CSSValueMenu:
    139         cachedDesc = &menuFont();
    140         if (!menuFont().isAbsoluteSize()) {
    141             NONCLIENTMETRICS metrics;
    142             getNonClientMetrics(&metrics);
    143             faceName = AtomicString(metrics.lfMenuFont.lfFaceName, wcslen(metrics.lfMenuFont.lfFaceName));
    144             fontSize = systemFontSize(metrics.lfMenuFont);
    145         }
    146         break;
    147     case CSSValueStatusBar:
    148         cachedDesc = &labelFont();
    149         if (!labelFont().isAbsoluteSize()) {
    150             NONCLIENTMETRICS metrics;
    151             getNonClientMetrics(&metrics);
    152             faceName = metrics.lfStatusFont.lfFaceName;
    153             fontSize = systemFontSize(metrics.lfStatusFont);
    154         }
    155         break;
    156     case CSSValueWebkitMiniControl:
    157     case CSSValueWebkitSmallControl:
    158     case CSSValueWebkitControl:
    159         faceName = defaultGUIFont();
    160         // Why 2 points smaller? Because that's what Gecko does.
    161         fontSize = s_defaultFontSize - pointsToPixels(2);
    162         break;
    163     default:
    164         faceName = defaultGUIFont();
    165         fontSize = s_defaultFontSize;
    166         break;
    167     }
    168 
    169     if (!cachedDesc)
    170         cachedDesc = &fontDescription;
    171 
    172     if (fontSize) {
    173         cachedDesc->firstFamily().setFamily(faceName);
    174         cachedDesc->setIsAbsoluteSize(true);
    175         cachedDesc->setGenericFamily(FontDescription::NoFamily);
    176         cachedDesc->setSpecifiedSize(fontSize);
    177         cachedDesc->setWeight(FontWeightNormal);
    178         cachedDesc->setItalic(false);
    179     }
    180     fontDescription = *cachedDesc;
    181 }
    182 
    183 // static
    184 void RenderThemeChromiumFontProvider::setDefaultFontSize(int fontSize)
    185 {
    186     s_defaultFontSize = static_cast<float>(fontSize);
    187 
    188     // Reset cached fonts.
    189     smallSystemFont() = menuFont() = labelFont() = FontDescription();
    190 }
    191 
    192 } // namespace WebCore
    193