1 /*
2 * Copyright (C) 2006, 2007, 2008 Apple 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 "Font.h"
28
29 #include "FontFallbackList.h"
30 #include "GlyphBuffer.h"
31 #include "GraphicsContext.h"
32 #include "IntRect.h"
33 #include "Logging.h"
34 #include "SimpleFontData.h"
35 #include "TextRun.h"
36 #include "UniscribeController.h"
37 #include <wtf/MathExtras.h>
38
39 using namespace std;
40
41 namespace WebCore {
42
canReturnFallbackFontsForComplexText()43 bool Font::canReturnFallbackFontsForComplexText()
44 {
45 return true;
46 }
47
canExpandAroundIdeographsInComplexText()48 bool Font::canExpandAroundIdeographsInComplexText()
49 {
50 return false;
51 }
52
selectionRectForComplexText(const TextRun & run,const FloatPoint & point,int h,int from,int to) const53 FloatRect Font::selectionRectForComplexText(const TextRun& run, const FloatPoint& point, int h,
54 int from, int to) const
55 {
56 UniscribeController it(this, run);
57 it.advance(from);
58 float beforeWidth = it.runWidthSoFar();
59 it.advance(to);
60 float afterWidth = it.runWidthSoFar();
61
62 // Using roundf() rather than ceilf() for the right edge as a compromise to ensure correct caret positioning
63 if (run.rtl()) {
64 it.advance(run.length());
65 float totalWidth = it.runWidthSoFar();
66 return FloatRect(point.x() + floorf(totalWidth - afterWidth), point.y(), roundf(totalWidth - beforeWidth) - floorf(totalWidth - afterWidth), h);
67 }
68
69 return FloatRect(point.x() + floorf(beforeWidth), point.y(), roundf(afterWidth) - floorf(beforeWidth), h);
70 }
71
getGlyphsAndAdvancesForComplexText(const TextRun & run,int from,int to,GlyphBuffer & glyphBuffer,ForTextEmphasisOrNot forTextEmphasis) const72 float Font::getGlyphsAndAdvancesForComplexText(const TextRun& run, int from, int to, GlyphBuffer& glyphBuffer, ForTextEmphasisOrNot forTextEmphasis) const
73 {
74 if (forTextEmphasis) {
75 // FIXME: Add forTextEmphasis paremeter to UniscribeController and use it.
76 LOG_ERROR("Not implemented for text emphasis.");
77 return 0;
78 }
79
80 UniscribeController controller(this, run);
81 controller.advance(from);
82 float beforeWidth = controller.runWidthSoFar();
83 controller.advance(to, &glyphBuffer);
84
85 if (glyphBuffer.isEmpty())
86 return 0;
87
88 float afterWidth = controller.runWidthSoFar();
89
90 if (run.rtl()) {
91 controller.advance(run.length());
92 return controller.runWidthSoFar() - afterWidth;
93 }
94 return beforeWidth;
95 }
96
drawComplexText(GraphicsContext * context,const TextRun & run,const FloatPoint & point,int from,int to) const97 void Font::drawComplexText(GraphicsContext* context, const TextRun& run, const FloatPoint& point,
98 int from, int to) const
99 {
100 // This glyph buffer holds our glyphs + advances + font data for each glyph.
101 GlyphBuffer glyphBuffer;
102
103 float startX = point.x() + getGlyphsAndAdvancesForComplexText(run, from, to, glyphBuffer);
104
105 // We couldn't generate any glyphs for the run. Give up.
106 if (glyphBuffer.isEmpty())
107 return;
108
109 // Draw the glyph buffer now at the starting point returned in startX.
110 FloatPoint startPoint(startX, point.y());
111 drawGlyphBuffer(context, glyphBuffer, startPoint);
112 }
113
drawEmphasisMarksForComplexText(GraphicsContext * context,const TextRun & run,const AtomicString & mark,const FloatPoint & point,int from,int to) const114 void Font::drawEmphasisMarksForComplexText(GraphicsContext* context, const TextRun& run, const AtomicString& mark, const FloatPoint& point, int from, int to) const
115 {
116 GlyphBuffer glyphBuffer;
117 float initialAdvance = getGlyphsAndAdvancesForComplexText(run, from, to, glyphBuffer, ForTextEmphasis);
118
119 if (glyphBuffer.isEmpty())
120 return;
121
122 drawEmphasisMarks(context, glyphBuffer, mark, FloatPoint(point.x() + initialAdvance, point.y()));
123 }
124
floatWidthForComplexText(const TextRun & run,HashSet<const SimpleFontData * > * fallbackFonts,GlyphOverflow * glyphOverflow) const125 float Font::floatWidthForComplexText(const TextRun& run, HashSet<const SimpleFontData*>* fallbackFonts, GlyphOverflow* glyphOverflow) const
126 {
127 UniscribeController controller(this, run, fallbackFonts);
128 controller.advance(run.length());
129 if (glyphOverflow) {
130 glyphOverflow->top = max<int>(glyphOverflow->top, ceilf(-controller.minGlyphBoundingBoxY()) - (glyphOverflow->computeBounds ? 0 : fontMetrics().ascent()));
131 glyphOverflow->bottom = max<int>(glyphOverflow->bottom, ceilf(controller.maxGlyphBoundingBoxY()) - (glyphOverflow->computeBounds ? 0 : fontMetrics().descent()));
132 glyphOverflow->left = max<int>(0, ceilf(-controller.minGlyphBoundingBoxX()));
133 glyphOverflow->right = max<int>(0, ceilf(controller.maxGlyphBoundingBoxX() - controller.runWidthSoFar()));
134 }
135 return controller.runWidthSoFar();
136 }
137
offsetForPositionForComplexText(const TextRun & run,float xFloat,bool includePartialGlyphs) const138 int Font::offsetForPositionForComplexText(const TextRun& run, float xFloat, bool includePartialGlyphs) const
139 {
140 // FIXME: This truncation is not a problem for HTML, but only affects SVG, which passes floating-point numbers
141 // to Font::offsetForPosition(). Bug http://webkit.org/b/40673 tracks fixing this problem.
142 int x = static_cast<int>(xFloat);
143
144 UniscribeController controller(this, run);
145 return controller.offsetForPosition(x, includePartialGlyphs);
146 }
147
148 }
149