1 /*
2 * Copyright (C) Research In Motion Limited 2010. All rights reserved.
3 *
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Library General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
8 *
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Library General Public License for more details.
13 *
14 * You should have received a copy of the GNU Library General Public License
15 * along with this library; see the file COPYING.LIB. If not, write to
16 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
17 * Boston, MA 02110-1301, USA.
18 */
19
20 #include "config.h"
21
22 #if ENABLE(SVG)
23 #include "SVGTextMetrics.h"
24
25 #include "RenderSVGInlineText.h"
26 #include "TextRun.h"
27
28 namespace WebCore {
29
SVGTextMetrics()30 SVGTextMetrics::SVGTextMetrics()
31 : m_width(0)
32 , m_height(0)
33 , m_length(0)
34 {
35 }
36
SVGTextMetrics(RenderSVGInlineText * textRenderer,const TextRun & run,unsigned position,unsigned textLength)37 SVGTextMetrics::SVGTextMetrics(RenderSVGInlineText* textRenderer, const TextRun& run, unsigned position, unsigned textLength)
38 {
39 ASSERT(textRenderer);
40
41 float scalingFactor = textRenderer->scalingFactor();
42 ASSERT(scalingFactor);
43
44 const Font& scaledFont = textRenderer->scaledFont();
45
46 int extraCharsAvailable = textLength - (position + run.length());
47 int length = 0;
48
49 // Calculate width/height using the scaled font, divide this result by the scalingFactor afterwards.
50 m_width = scaledFont.width(run, extraCharsAvailable, length, m_glyph.name) / scalingFactor;
51 m_height = scaledFont.fontMetrics().floatHeight() / scalingFactor;
52
53 m_glyph.unicodeString = String(run.characters(), length);
54 m_glyph.isValid = true;
55
56 ASSERT(length >= 0);
57 m_length = static_cast<unsigned>(length);
58 }
59
operator ==(const SVGTextMetrics & other)60 bool SVGTextMetrics::operator==(const SVGTextMetrics& other)
61 {
62 return m_width == other.m_width
63 && m_height == other.m_height
64 && m_length == other.m_length
65 && m_glyph == other.m_glyph;
66 }
67
emptyMetrics()68 SVGTextMetrics SVGTextMetrics::emptyMetrics()
69 {
70 DEFINE_STATIC_LOCAL(SVGTextMetrics, s_emptyMetrics, ());
71 s_emptyMetrics.m_length = 1;
72 return s_emptyMetrics;
73 }
74
constructTextRun(RenderSVGInlineText * text,const UChar * characters,unsigned position,unsigned length)75 static TextRun constructTextRun(RenderSVGInlineText* text, const UChar* characters, unsigned position, unsigned length)
76 {
77 RenderStyle* style = text->style();
78 ASSERT(style);
79
80 TextRun run(characters + position
81 , length
82 , false /* allowTabs */
83 , 0 /* xPos, only relevant with allowTabs=true */
84 , 0 /* padding, only relevant for justified text, not relevant for SVG */
85 , TextRun::AllowTrailingExpansion
86 , !style->isLeftToRightDirection()
87 , style->unicodeBidi() == Override /* directionalOverride */);
88
89 #if ENABLE(SVG_FONTS)
90 run.setReferencingRenderObject(text);
91 #endif
92
93 // We handle letter & word spacing ourselves.
94 run.disableSpacing();
95 return run;
96 }
97
measureCharacterRange(RenderSVGInlineText * text,unsigned position,unsigned length)98 SVGTextMetrics SVGTextMetrics::measureCharacterRange(RenderSVGInlineText* text, unsigned position, unsigned length)
99 {
100 ASSERT(text);
101 TextRun run(constructTextRun(text, text->characters(), position, length));
102 return SVGTextMetrics(text, run, position, text->textLength());
103 }
104
105 }
106
107 #endif // ENABLE(SVG)
108