1/*
2 * Copyright (C) 2006, 2007, 2008, 2009 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 INC. AND ITS CONTRIBUTORS ``AS IS'' AND ANY
14 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
15 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
16 * DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS BE LIABLE FOR ANY
17 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
18 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
19 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
20 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
21 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
22 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
23 */
24
25#include "config.h"
26#include "Font.h"
27
28#include "ComplexTextController.h"
29#include "FontFallbackList.h"
30#include "GlyphBuffer.h"
31#include "GraphicsContext.h"
32#include "IntRect.h"
33#include "SimpleFontData.h"
34#include "TextRun.h"
35#include <wtf/MathExtras.h>
36
37using namespace std;
38
39namespace WebCore {
40
41FloatRect Font::selectionRectForComplexText(const TextRun& run, const FloatPoint& point, int h,
42                                            int from, int to) const
43{
44    ComplexTextController controller(this, run);
45    controller.advance(from);
46    float beforeWidth = controller.runWidthSoFar();
47    controller.advance(to);
48    float afterWidth = controller.runWidthSoFar();
49
50    // Using roundf() rather than ceilf() for the right edge as a compromise to ensure correct caret positioning
51    if (run.rtl()) {
52        float totalWidth = controller.totalWidth();
53        return FloatRect(point.x() + floorf(totalWidth - afterWidth), point.y(), roundf(totalWidth - beforeWidth) - floorf(totalWidth - afterWidth), h);
54    }
55
56    return FloatRect(point.x() + floorf(beforeWidth), point.y(), roundf(afterWidth) - floorf(beforeWidth), h);
57}
58
59float Font::getGlyphsAndAdvancesForComplexText(const TextRun& run, int from, int to, GlyphBuffer& glyphBuffer, ForTextEmphasisOrNot forTextEmphasis) const
60{
61    float initialAdvance;
62
63    ComplexTextController controller(this, run, false, 0, forTextEmphasis);
64    controller.advance(from);
65    float beforeWidth = controller.runWidthSoFar();
66    controller.advance(to, &glyphBuffer);
67
68    if (glyphBuffer.isEmpty())
69        return 0;
70
71    float afterWidth = controller.runWidthSoFar();
72
73    if (run.rtl()) {
74        initialAdvance = controller.totalWidth() - afterWidth;
75        for (int i = 0, end = glyphBuffer.size() - 1; i < glyphBuffer.size() / 2; ++i, --end)
76            glyphBuffer.swap(i, end);
77    } else
78        initialAdvance = beforeWidth;
79
80    return initialAdvance;
81}
82
83void Font::drawComplexText(GraphicsContext* context, const TextRun& run, const FloatPoint& point, int from, int to) const
84{
85    // This glyph buffer holds our glyphs + advances + font data for each glyph.
86    GlyphBuffer glyphBuffer;
87
88    float startX = point.x() + getGlyphsAndAdvancesForComplexText(run, from, to, glyphBuffer);
89
90    // We couldn't generate any glyphs for the run.  Give up.
91    if (glyphBuffer.isEmpty())
92        return;
93
94    // Draw the glyph buffer now at the starting point returned in startX.
95    FloatPoint startPoint(startX, point.y());
96    drawGlyphBuffer(context, glyphBuffer, startPoint);
97}
98
99void Font::drawEmphasisMarksForComplexText(GraphicsContext* context, const TextRun& run, const AtomicString& mark, const FloatPoint& point, int from, int to) const
100{
101    GlyphBuffer glyphBuffer;
102    float initialAdvance = getGlyphsAndAdvancesForComplexText(run, from, to, glyphBuffer, ForTextEmphasis);
103
104    if (glyphBuffer.isEmpty())
105        return;
106
107    drawEmphasisMarks(context, glyphBuffer, mark, FloatPoint(point.x() + initialAdvance, point.y()));
108}
109
110float Font::floatWidthForComplexText(const TextRun& run, HashSet<const SimpleFontData*>* fallbackFonts, GlyphOverflow* glyphOverflow) const
111{
112    ComplexTextController controller(this, run, true, fallbackFonts);
113    if (glyphOverflow) {
114        glyphOverflow->top = max<int>(glyphOverflow->top, ceilf(-controller.minGlyphBoundingBoxY()) - (glyphOverflow->computeBounds ? 0 : fontMetrics().ascent()));
115        glyphOverflow->bottom = max<int>(glyphOverflow->bottom, ceilf(controller.maxGlyphBoundingBoxY()) - (glyphOverflow->computeBounds ? 0 : fontMetrics().descent()));
116        glyphOverflow->left = max<int>(0, ceilf(-controller.minGlyphBoundingBoxX()));
117        glyphOverflow->right = max<int>(0, ceilf(controller.maxGlyphBoundingBoxX() - controller.totalWidth()));
118    }
119    return controller.totalWidth();
120}
121
122int Font::offsetForPositionForComplexText(const TextRun& run, float x, bool includePartialGlyphs) const
123{
124    ComplexTextController controller(this, run);
125    return controller.offsetForPosition(x, includePartialGlyphs);
126}
127
128} // namespace WebCore
129