1 // Copyright 2017 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "third_party/blink/renderer/core/paint/ng/ng_text_painter.h"
6
7 #include "third_party/blink/renderer/core/css/css_property_names.h"
8 #include "third_party/blink/renderer/core/frame/settings.h"
9 #include "third_party/blink/renderer/core/layout/ng/inline/ng_physical_text_fragment.h"
10 #include "third_party/blink/renderer/core/layout/ng/ng_unpositioned_float.h"
11 #include "third_party/blink/renderer/core/paint/box_painter.h"
12 #include "third_party/blink/renderer/core/paint/paint_info.h"
13 #include "third_party/blink/renderer/core/paint/paint_timing_detector.h"
14 #include "third_party/blink/renderer/core/style/computed_style.h"
15 #include "third_party/blink/renderer/core/style/shadow_list.h"
16 #include "third_party/blink/renderer/platform/fonts/font.h"
17 #include "third_party/blink/renderer/platform/graphics/graphics_context.h"
18 #include "third_party/blink/renderer/platform/graphics/graphics_context_state_saver.h"
19 #include "third_party/blink/renderer/platform/graphics/paint/paint_controller.h"
20 #include "third_party/blink/renderer/platform/wtf/assertions.h"
21 #include "third_party/blink/renderer/platform/wtf/text/character_names.h"
22
23 namespace blink {
24
Paint(unsigned start_offset,unsigned end_offset,unsigned length,const TextPaintStyle & text_style,DOMNodeId node_id)25 void NGTextPainter::Paint(unsigned start_offset,
26 unsigned end_offset,
27 unsigned length,
28 const TextPaintStyle& text_style,
29 DOMNodeId node_id) {
30 GraphicsContextStateSaver state_saver(graphics_context_, false);
31 UpdateGraphicsContext(text_style, state_saver);
32 // TODO(layout-dev): Handle combine text here or elsewhere.
33 PaintInternal<kPaintText>(start_offset, end_offset, length, node_id);
34
35 if (!emphasis_mark_.IsEmpty()) {
36 if (text_style.emphasis_mark_color != text_style.fill_color)
37 graphics_context_.SetFillColor(text_style.emphasis_mark_color);
38 PaintInternal<kPaintEmphasisMark>(start_offset, end_offset, length,
39 node_id);
40 }
41 }
42
43 // This function paints text twice with different styles in order to:
44 // 1. Paint glyphs inside of |selection_rect| using |selection_style|, and
45 // outside using |text_style|.
46 // 2. Paint parts of a ligature glyph.
PaintSelectedText(unsigned start_offset,unsigned end_offset,unsigned length,const TextPaintStyle & text_style,const TextPaintStyle & selection_style,const PhysicalRect & selection_rect,DOMNodeId node_id)47 void NGTextPainter::PaintSelectedText(unsigned start_offset,
48 unsigned end_offset,
49 unsigned length,
50 const TextPaintStyle& text_style,
51 const TextPaintStyle& selection_style,
52 const PhysicalRect& selection_rect,
53 DOMNodeId node_id) {
54 if (!fragment_paint_info_.shape_result)
55 return;
56
57 // Use fast path if all glyphs fit in |selection_rect|. |visual_rect_| is the
58 // ink bounds of all glyphs of this text fragment, including characters before
59 // |start_offset| or after |end_offset|. Computing exact bounds is expensive
60 // that this code only checks bounds of all glyphs.
61 IntRect snapped_selection_rect(PixelSnappedIntRect(selection_rect));
62 // Allowing 1px overflow is almost unnoticeable, while it can avoid two-pass
63 // painting in most small text.
64 snapped_selection_rect.Inflate(1);
65 if (snapped_selection_rect.Contains(visual_rect_)) {
66 Paint(start_offset, end_offset, length, selection_style, node_id);
67 return;
68 }
69
70 // Adjust start/end offset when they are in the middle of a ligature. e.g.,
71 // when |start_offset| is between a ligature of "fi", it needs to be adjusted
72 // to before "f".
73 fragment_paint_info_.shape_result->ExpandRangeToIncludePartialGlyphs(
74 &start_offset, &end_offset);
75
76 // Because only a part of the text glyph can be selected, we need to draw
77 // the selection twice. First, draw the glyphs outside the selection area,
78 // with the original style.
79 FloatRect float_selection_rect(selection_rect);
80 {
81 GraphicsContextStateSaver state_saver(graphics_context_);
82 graphics_context_.ClipOut(float_selection_rect);
83 Paint(start_offset, end_offset, length, text_style, node_id);
84 }
85 // Then draw the glyphs inside the selection area, with the selection style.
86 {
87 GraphicsContextStateSaver state_saver(graphics_context_);
88 graphics_context_.Clip(float_selection_rect);
89 Paint(start_offset, end_offset, length, selection_style, node_id);
90 }
91 }
92
93 template <NGTextPainter::PaintInternalStep step>
PaintInternalFragment(unsigned from,unsigned to,DOMNodeId node_id)94 void NGTextPainter::PaintInternalFragment(
95 unsigned from,
96 unsigned to,
97 DOMNodeId node_id) {
98 DCHECK(from <= fragment_paint_info_.text.length());
99 DCHECK(to <= fragment_paint_info_.text.length());
100
101 fragment_paint_info_.from = from;
102 fragment_paint_info_.to = to;
103
104 if (step == kPaintEmphasisMark) {
105 graphics_context_.DrawEmphasisMarks(
106 font_, fragment_paint_info_, emphasis_mark_,
107 FloatPoint(text_origin_) + IntSize(0, emphasis_mark_offset_));
108 } else {
109 DCHECK(step == kPaintText);
110 graphics_context_.DrawText(font_, fragment_paint_info_,
111 FloatPoint(text_origin_), node_id);
112 // TODO(npm): Check that there are non-whitespace characters. See
113 // crbug.com/788444.
114 graphics_context_.GetPaintController().SetTextPainted();
115
116 if (!font_.ShouldSkipDrawing())
117 PaintTimingDetector::NotifyTextPaint(visual_rect_);
118 }
119 }
120
121 template <NGTextPainter::PaintInternalStep Step>
PaintInternal(unsigned start_offset,unsigned end_offset,unsigned truncation_point,DOMNodeId node_id)122 void NGTextPainter::PaintInternal(unsigned start_offset,
123 unsigned end_offset,
124 unsigned truncation_point,
125 DOMNodeId node_id) {
126 // TODO(layout-dev): We shouldn't be creating text fragments without text.
127 if (!fragment_paint_info_.shape_result)
128 return;
129
130 if (start_offset <= end_offset) {
131 PaintInternalFragment<Step>(start_offset, end_offset, node_id);
132 } else {
133 if (end_offset > 0) {
134 PaintInternalFragment<Step>(ellipsis_offset_, end_offset, node_id);
135 }
136 if (start_offset < truncation_point) {
137 PaintInternalFragment<Step>(start_offset, truncation_point, node_id);
138 }
139 }
140 }
141
ClipDecorationsStripe(float upper,float stripe_width,float dilation)142 void NGTextPainter::ClipDecorationsStripe(float upper,
143 float stripe_width,
144 float dilation) {
145 if (fragment_paint_info_.from >= fragment_paint_info_.to ||
146 !fragment_paint_info_.shape_result)
147 return;
148
149 Vector<Font::TextIntercept> text_intercepts;
150 font_.GetTextIntercepts(
151 fragment_paint_info_, graphics_context_.DeviceScaleFactor(),
152 graphics_context_.FillFlags(),
153 std::make_tuple(upper, upper + stripe_width), text_intercepts);
154
155 DecorationsStripeIntercepts(upper, stripe_width, dilation, text_intercepts);
156 }
157
PaintEmphasisMarkForCombinedText()158 void NGTextPainter::PaintEmphasisMarkForCombinedText() {}
159
160 } // namespace blink
161