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#pragma once
21
22#include "AffineTransform.h"
23
24namespace WebCore {
25
26// A SVGTextFragment describes a text fragment of a RenderSVGInlineText which can be rendered at once.
27struct SVGTextFragment {
28 SVGTextFragment()
29 : characterOffset(0)
30 , metricsListOffset(0)
31 , length(0)
32 , isTextOnPath(false)
33 , x(0)
34 , y(0)
35 , width(0)
36 , height(0)
37 {
38 }
39
40 enum TransformType {
41 TransformRespectingTextLength,
42 TransformIgnoringTextLength
43 };
44
45 void buildFragmentTransform(AffineTransform& result, TransformType type = TransformRespectingTextLength) const
46 {
47 if (type == TransformIgnoringTextLength) {
48 result = transform;
49 transformAroundOrigin(result);
50 return;
51 }
52
53 if (isTextOnPath)
54 buildTransformForTextOnPath(result);
55 else
56 buildTransformForTextOnLine(result);
57 }
58
59 // The first rendered character starts at RenderSVGInlineText::characters() + characterOffset.
60 unsigned characterOffset;
61 unsigned metricsListOffset;
62 unsigned length : 31;
63 bool isTextOnPath : 1;
64
65 float x;
66 float y;
67 float width;
68 float height;
69
70 // Includes rotation/glyph-orientation-(horizontal|vertical) transforms, as well as orientation related shifts
71 // (see SVGTextLayoutEngine, which builds this transformation).
72 AffineTransform transform;
73
74 // Contains lengthAdjust related transformations, which are not allowd to influence the SVGTextQuery code.
75 AffineTransform lengthAdjustTransform;
76
77private:
78 void transformAroundOrigin(AffineTransform& result) const
79 {
80 // Returns (translate(x, y) * result) * translate(-x, -y).
81 result.setE(result.e() + x);
82 result.setF(result.f() + y);
83 result.translate(-x, -y);
84 }
85
86 void buildTransformForTextOnPath(AffineTransform& result) const
87 {
88 // For text-on-path layout, multiply the transform with the lengthAdjustTransform before orienting the resulting transform.
89 result = lengthAdjustTransform.isIdentity() ? transform : transform * lengthAdjustTransform;
90 if (!result.isIdentity())
91 transformAroundOrigin(result);
92 }
93
94 void buildTransformForTextOnLine(AffineTransform& result) const
95 {
96 // For text-on-line layout, orient the transform first, then multiply the lengthAdjustTransform with the oriented transform.
97 if (transform.isIdentity()) {
98 result = lengthAdjustTransform;
99 return;
100 }
101
102 result = transform;
103 transformAroundOrigin(result);
104
105 if (!lengthAdjustTransform.isIdentity())
106 result = lengthAdjustTransform * result;
107 }
108};
109
110} // namespace WebCore
111