third_party/blink/renderer/core/paint/document_marker_painter.cc - chromium/src - Git at Google

 // Copyright 2018 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

 #include "third_party/blink/renderer/core/paint/document_marker_painter.h"

 #include "build/build_config.h"
 #include "third_party/blink/renderer/core/editing/markers/document_marker_controller.h"
 #include "third_party/blink/renderer/core/layout/layout_theme.h"
 #include "third_party/blink/renderer/core/paint/text_paint_style.h"
 #include "third_party/blink/renderer/core/style/computed_style.h"
 #include "third_party/blink/renderer/platform/fonts/simple_font_data.h"
 #include "third_party/blink/renderer/platform/geometry/layout_unit.h"
 #include "third_party/blink/renderer/platform/graphics/graphics_context_state_saver.h"

 namespace blink {

 namespace {

 #if !defined(OS_MACOSX)

 static const float kMarkerWidth = 4;
 static const float kMarkerHeight = 2;

 sk_sp<PaintRecord> RecordMarker(Color blink_color) {
   const SkColor color = blink_color.Rgb();

   // Record the path equivalent to this legacy pattern:
   //   X o   o X o   o X
   //     o X o   o X o

   // Adjust the phase such that f' == 0 is "pixel"-centered
   // (for optimal rasterization at native rez).
   SkPath path;
   path.moveTo(kMarkerWidth * -3 / 8, kMarkerHeight * 3 / 4);
   path.cubicTo(kMarkerWidth * -1 / 8, kMarkerHeight * 3 / 4,
                kMarkerWidth * -1 / 8, kMarkerHeight * 1 / 4,
                kMarkerWidth * 1 / 8, kMarkerHeight * 1 / 4);
   path.cubicTo(kMarkerWidth * 3 / 8, kMarkerHeight * 1 / 4,
                kMarkerWidth * 3 / 8, kMarkerHeight * 3 / 4,
                kMarkerWidth * 5 / 8, kMarkerHeight * 3 / 4);
   path.cubicTo(kMarkerWidth * 7 / 8, kMarkerHeight * 3 / 4,
                kMarkerWidth * 7 / 8, kMarkerHeight * 1 / 4,
                kMarkerWidth * 9 / 8, kMarkerHeight * 1 / 4);

   PaintFlags flags;
   flags.setAntiAlias(true);
   flags.setColor(color);
   flags.setStyle(PaintFlags::kStroke_Style);
   flags.setStrokeWidth(kMarkerHeight * 1 / 2);

   PaintRecorder recorder;
   recorder.beginRecording(kMarkerWidth, kMarkerHeight);
   recorder.getRecordingCanvas()->drawPath(path, flags);

   return recorder.finishRecordingAsPicture();
 }

 #else  // defined(OS_MACOSX)

 static const float kMarkerWidth = 4;
 static const float kMarkerHeight = 3;

 sk_sp<PaintRecord> RecordMarker(Color blink_color) {
   const SkColor color = blink_color.Rgb();

   // Match the artwork used by the Mac.
   static const float kR = 1.5f;

   // top->bottom translucent gradient.
   const SkColor colors[2] = {
       SkColorSetARGB(0x48, SkColorGetR(color), SkColorGetG(color),
                      SkColorGetB(color)),
       color};
   const SkPoint pts[2] = {SkPoint::Make(0, 0), SkPoint::Make(0, 2 * kR)};

   PaintFlags flags;
   flags.setAntiAlias(true);
   flags.setColor(color);
   flags.setShader(PaintShader::MakeLinearGradient(
       pts, colors, nullptr, ARRAY_SIZE(colors), SkShader::kClamp_TileMode));
   PaintRecorder recorder;
   recorder.beginRecording(kMarkerWidth, kMarkerHeight);
   recorder.getRecordingCanvas()->drawOval(SkRect::MakeWH(2 * kR, 2 * kR),
                                           flags);
   return recorder.finishRecordingAsPicture();
 }

 #endif  // defined(OS_MACOSX)

 void DrawDocumentMarker(GraphicsContext& context,
                         const FloatPoint& pt,
                         float width,
                         DocumentMarker::MarkerType marker_type,
                         float zoom) {
   DCHECK(marker_type == DocumentMarker::kSpelling ||
          marker_type == DocumentMarker::kGrammar);

   DEFINE_STATIC_LOCAL(
       PaintRecord*, spelling_marker,
       (RecordMarker(
            LayoutTheme::GetTheme().PlatformSpellingMarkerUnderlineColor())
            .release()));
   DEFINE_STATIC_LOCAL(
       PaintRecord*, grammar_marker,
       (RecordMarker(
            LayoutTheme::GetTheme().PlatformGrammarMarkerUnderlineColor())
            .release()));
   auto* const marker = marker_type == DocumentMarker::kSpelling
                            ? spelling_marker
                            : grammar_marker;

   // Position already includes zoom and device scale factor.
   SkScalar origin_x = WebCoreFloatToSkScalar(pt.X());
   SkScalar origin_y = WebCoreFloatToSkScalar(pt.Y());

 #if defined(OS_MACOSX)
   // Make sure to draw only complete dots, and finish inside the marked text.
   width -= fmodf(width, kMarkerWidth * zoom);
 #else
   // Offset it vertically by 1 so that there's some space under the text.
   origin_y += 1;
 #endif

   const auto rect = SkRect::MakeWH(width, kMarkerHeight * zoom);
   const auto local_matrix = SkMatrix::MakeScale(zoom, zoom);

   PaintFlags flags;
   flags.setAntiAlias(true);
   flags.setShader(PaintShader::MakePaintRecord(
       sk_ref_sp(marker), FloatRect(0, 0, kMarkerWidth, kMarkerHeight),
       SkShader::kRepeat_TileMode, SkShader::kClamp_TileMode, &local_matrix));

   // Apply the origin translation as a global transform.  This ensures that the
   // shader local matrix depends solely on zoom => Skia can reuse the same
   // cached tile for all markers at a given zoom level.
   GraphicsContextStateSaver saver(context);
   context.Translate(origin_x, origin_y);
   context.DrawRect(rect, flags);
 }

 }  // anonymous ns

 void DocumentMarkerPainter::PaintStyleableMarkerUnderline(
     GraphicsContext& context,
     const LayoutPoint& box_origin,
     const StyleableMarker& marker,
     const ComputedStyle& style,
     const FloatRect& marker_rect,
     LayoutUnit logical_height) {
   if (marker.HasThicknessNone() ||
       (marker.UnderlineColor() == Color::kTransparent &&
        !marker.UseTextColor()))
     return;

   // start of line to draw, relative to box_origin.X()
   LayoutUnit start = LayoutUnit(marker_rect.X());
   LayoutUnit width = LayoutUnit(marker_rect.Width());

   // We need to have some space between underlines of subsequent clauses,
   // because some input methods do not use different underline styles for those.
   // We make each line shorter, which has a harmless side effect of shortening
   // the first and last clauses, too.
   start += 1;
   width -= 2;

   // Thick marked text underlines are 2px thick as long as there is room for the
   // 2px line under the baseline.  All other marked text underlines are 1px
   // thick.  If there's not enough space the underline will touch or overlap
   // characters.
   int line_thickness = 1;
   const SimpleFontData* font_data = style.GetFont().PrimaryFont();
   DCHECK(font_data);
   int baseline = font_data ? font_data->GetFontMetrics().Ascent() : 0;
   if (marker.HasThicknessThick() && logical_height.ToInt() - baseline >= 2)
     line_thickness = 2;

   // Line thickness should change with zoom.
   line_thickness *= style.EffectiveZoom();

   Color marker_color =
       marker.UseTextColor()
           ? style.VisitedDependentColor(GetCSSPropertyWebkitTextFillColor())
           : marker.UnderlineColor();
   context.SetStrokeColor(marker_color);

   context.SetStrokeThickness(line_thickness);
   context.DrawLineForText(
       FloatPoint(
           box_origin.X() + start,
           (box_origin.Y() + logical_height.ToInt() - line_thickness).ToFloat()),
       width);
 }

 static const int kMisspellingLineThickness = 3;

 void DocumentMarkerPainter::PaintDocumentMarker(
     GraphicsContext& context,
     const LayoutPoint& box_origin,
     const ComputedStyle& style,
     DocumentMarker::MarkerType marker_type,
     const LayoutRect& local_rect) {
   // IMPORTANT: The misspelling underline is not considered when calculating the
   // text bounds, so we have to make sure to fit within those bounds.  This
   // means the top pixel(s) of the underline will overlap the bottom pixel(s) of
   // the glyphs in smaller font sizes.  The alternatives are to increase the
   // line spacing (bad!!) or decrease the underline thickness.  The overlap is
   // actually the most useful, and matches what AppKit does.  So, we generally
   // place the underline at the bottom of the text, but in larger fonts that's
   // not so good so we pin to two pixels under the baseline.
   int line_thickness = kMisspellingLineThickness;

   const SimpleFontData* font_data = style.GetFont().PrimaryFont();
   DCHECK(font_data);
   int baseline = font_data->GetFontMetrics().Ascent();
   int descent = (local_rect.Height() - baseline).ToInt();
   int underline_offset;
   if (descent <= (line_thickness + 2)) {
     // Place the underline at the very bottom of the text in small/medium fonts.
     underline_offset = (local_rect.Height() - line_thickness).ToInt();
   } else {
     // In larger fonts, though, place the underline up near the baseline to
     // prevent a big gap.
     underline_offset = baseline + 2;
   }
   DrawDocumentMarker(context,
                      FloatPoint((box_origin.X() + local_rect.X()).ToFloat(),
                                 (box_origin.Y() + underline_offset).ToFloat()),
                      local_rect.Width().ToFloat(), marker_type,
                      style.EffectiveZoom());
 }

 TextPaintStyle DocumentMarkerPainter::ComputeTextPaintStyleFrom(
     const ComputedStyle& style,
     const TextMatchMarker& marker) {
   const Color text_color =
       LayoutTheme::GetTheme().PlatformTextSearchColor(marker.IsActiveMatch());
   if (style.VisitedDependentColor(GetCSSPropertyColor()) == text_color)
     return {};

   TextPaintStyle text_style;
   text_style.current_color = text_style.fill_color = text_style.stroke_color =
       text_style.emphasis_mark_color = text_color;
   text_style.stroke_width = style.TextStrokeWidth();
   text_style.shadow = nullptr;
   return text_style;
 }
 }  // namespace blink
	// Copyright 2018 The Chromium Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.

	#include "third_party/blink/renderer/core/paint/document_marker_painter.h"

	#include "build/build_config.h"
	#include "third_party/blink/renderer/core/editing/markers/document_marker_controller.h"
	#include "third_party/blink/renderer/core/layout/layout_theme.h"
	#include "third_party/blink/renderer/core/paint/text_paint_style.h"
	#include "third_party/blink/renderer/core/style/computed_style.h"
	#include "third_party/blink/renderer/platform/fonts/simple_font_data.h"
	#include "third_party/blink/renderer/platform/geometry/layout_unit.h"
	#include "third_party/blink/renderer/platform/graphics/graphics_context_state_saver.h"

	namespace blink {

	namespace {

	#if !defined(OS_MACOSX)

	static const float kMarkerWidth = 4;
	static const float kMarkerHeight = 2;

	sk_sp<PaintRecord> RecordMarker(Color blink_color) {
	const SkColor color = blink_color.Rgb();

	// Record the path equivalent to this legacy pattern:
	// X o o X o o X
	// o X o o X o

	// Adjust the phase such that f' == 0 is "pixel"-centered
	// (for optimal rasterization at native rez).
	SkPath path;
	path.moveTo(kMarkerWidth * -3 / 8, kMarkerHeight * 3 / 4);
	path.cubicTo(kMarkerWidth * -1 / 8, kMarkerHeight * 3 / 4,
	kMarkerWidth * -1 / 8, kMarkerHeight * 1 / 4,
	kMarkerWidth * 1 / 8, kMarkerHeight * 1 / 4);
	path.cubicTo(kMarkerWidth * 3 / 8, kMarkerHeight * 1 / 4,
	kMarkerWidth * 3 / 8, kMarkerHeight * 3 / 4,
	kMarkerWidth * 5 / 8, kMarkerHeight * 3 / 4);
	path.cubicTo(kMarkerWidth * 7 / 8, kMarkerHeight * 3 / 4,
	kMarkerWidth * 7 / 8, kMarkerHeight * 1 / 4,
	kMarkerWidth * 9 / 8, kMarkerHeight * 1 / 4);

	PaintFlags flags;
	flags.setAntiAlias(true);
	flags.setColor(color);
	flags.setStyle(PaintFlags::kStroke_Style);
	flags.setStrokeWidth(kMarkerHeight * 1 / 2);

	PaintRecorder recorder;
	recorder.beginRecording(kMarkerWidth, kMarkerHeight);
	recorder.getRecordingCanvas()->drawPath(path, flags);

	return recorder.finishRecordingAsPicture();
	}

	#else // defined(OS_MACOSX)

	static const float kMarkerWidth = 4;
	static const float kMarkerHeight = 3;

	sk_sp<PaintRecord> RecordMarker(Color blink_color) {
	const SkColor color = blink_color.Rgb();

	// Match the artwork used by the Mac.
	static const float kR = 1.5f;

	// top->bottom translucent gradient.
	const SkColor colors[2] = {
	SkColorSetARGB(0x48, SkColorGetR(color), SkColorGetG(color),
	SkColorGetB(color)),
	color};
	const SkPoint pts[2] = {SkPoint::Make(0, 0), SkPoint::Make(0, 2 * kR)};

	PaintFlags flags;
	flags.setAntiAlias(true);
	flags.setColor(color);
	flags.setShader(PaintShader::MakeLinearGradient(
	pts, colors, nullptr, ARRAY_SIZE(colors), SkShader::kClamp_TileMode));
	PaintRecorder recorder;
	recorder.beginRecording(kMarkerWidth, kMarkerHeight);
	recorder.getRecordingCanvas()->drawOval(SkRect::MakeWH(2 * kR, 2 * kR),
	flags);
	return recorder.finishRecordingAsPicture();
	}

	#endif // defined(OS_MACOSX)

	void DrawDocumentMarker(GraphicsContext& context,
	const FloatPoint& pt,
	float width,
	DocumentMarker::MarkerType marker_type,
	float zoom) {
	DCHECK(marker_type == DocumentMarker::kSpelling \|\|
	marker_type == DocumentMarker::kGrammar);

	DEFINE_STATIC_LOCAL(
	PaintRecord*, spelling_marker,
	(RecordMarker(
	LayoutTheme::GetTheme().PlatformSpellingMarkerUnderlineColor())
	.release()));
	DEFINE_STATIC_LOCAL(
	PaintRecord*, grammar_marker,
	(RecordMarker(
	LayoutTheme::GetTheme().PlatformGrammarMarkerUnderlineColor())
	.release()));
	auto* const marker = marker_type == DocumentMarker::kSpelling
	? spelling_marker
	: grammar_marker;

	// Position already includes zoom and device scale factor.
	SkScalar origin_x = WebCoreFloatToSkScalar(pt.X());
	SkScalar origin_y = WebCoreFloatToSkScalar(pt.Y());

	#if defined(OS_MACOSX)
	// Make sure to draw only complete dots, and finish inside the marked text.
	width -= fmodf(width, kMarkerWidth * zoom);
	#else
	// Offset it vertically by 1 so that there's some space under the text.
	origin_y += 1;
	#endif

	const auto rect = SkRect::MakeWH(width, kMarkerHeight * zoom);
	const auto local_matrix = SkMatrix::MakeScale(zoom, zoom);

	PaintFlags flags;
	flags.setAntiAlias(true);
	flags.setShader(PaintShader::MakePaintRecord(
	sk_ref_sp(marker), FloatRect(0, 0, kMarkerWidth, kMarkerHeight),
	SkShader::kRepeat_TileMode, SkShader::kClamp_TileMode, &local_matrix));

	// Apply the origin translation as a global transform. This ensures that the
	// shader local matrix depends solely on zoom => Skia can reuse the same
	// cached tile for all markers at a given zoom level.
	GraphicsContextStateSaver saver(context);
	context.Translate(origin_x, origin_y);
	context.DrawRect(rect, flags);
	}

	} // anonymous ns

	void DocumentMarkerPainter::PaintStyleableMarkerUnderline(
	GraphicsContext& context,
	const LayoutPoint& box_origin,
	const StyleableMarker& marker,
	const ComputedStyle& style,
	const FloatRect& marker_rect,
	LayoutUnit logical_height) {
	if (marker.HasThicknessNone() \|\|
	(marker.UnderlineColor() == Color::kTransparent &&
	!marker.UseTextColor()))
	return;

	// start of line to draw, relative to box_origin.X()
	LayoutUnit start = LayoutUnit(marker_rect.X());
	LayoutUnit width = LayoutUnit(marker_rect.Width());

	// We need to have some space between underlines of subsequent clauses,
	// because some input methods do not use different underline styles for those.
	// We make each line shorter, which has a harmless side effect of shortening
	// the first and last clauses, too.
	start += 1;
	width -= 2;

	// Thick marked text underlines are 2px thick as long as there is room for the
	// 2px line under the baseline. All other marked text underlines are 1px
	// thick. If there's not enough space the underline will touch or overlap
	// characters.
	int line_thickness = 1;
	const SimpleFontData* font_data = style.GetFont().PrimaryFont();
	DCHECK(font_data);
	int baseline = font_data ? font_data->GetFontMetrics().Ascent() : 0;
	if (marker.HasThicknessThick() && logical_height.ToInt() - baseline >= 2)
	line_thickness = 2;

	// Line thickness should change with zoom.
	line_thickness *= style.EffectiveZoom();

	Color marker_color =
	marker.UseTextColor()
	? style.VisitedDependentColor(GetCSSPropertyWebkitTextFillColor())
	: marker.UnderlineColor();
	context.SetStrokeColor(marker_color);

	context.SetStrokeThickness(line_thickness);
	context.DrawLineForText(
	FloatPoint(
	box_origin.X() + start,
	(box_origin.Y() + logical_height.ToInt() - line_thickness).ToFloat()),
	width);
	}

	static const int kMisspellingLineThickness = 3;

	void DocumentMarkerPainter::PaintDocumentMarker(
	GraphicsContext& context,
	const LayoutPoint& box_origin,
	const ComputedStyle& style,
	DocumentMarker::MarkerType marker_type,
	const LayoutRect& local_rect) {
	// IMPORTANT: The misspelling underline is not considered when calculating the
	// text bounds, so we have to make sure to fit within those bounds. This
	// means the top pixel(s) of the underline will overlap the bottom pixel(s) of
	// the glyphs in smaller font sizes. The alternatives are to increase the
	// line spacing (bad!!) or decrease the underline thickness. The overlap is
	// actually the most useful, and matches what AppKit does. So, we generally
	// place the underline at the bottom of the text, but in larger fonts that's
	// not so good so we pin to two pixels under the baseline.
	int line_thickness = kMisspellingLineThickness;

	const SimpleFontData* font_data = style.GetFont().PrimaryFont();
	DCHECK(font_data);
	int baseline = font_data->GetFontMetrics().Ascent();
	int descent = (local_rect.Height() - baseline).ToInt();
	int underline_offset;
	if (descent <= (line_thickness + 2)) {
	// Place the underline at the very bottom of the text in small/medium fonts.
	underline_offset = (local_rect.Height() - line_thickness).ToInt();
	} else {
	// In larger fonts, though, place the underline up near the baseline to
	// prevent a big gap.
	underline_offset = baseline + 2;
	}
	DrawDocumentMarker(context,
	FloatPoint((box_origin.X() + local_rect.X()).ToFloat(),
	(box_origin.Y() + underline_offset).ToFloat()),
	local_rect.Width().ToFloat(), marker_type,
	style.EffectiveZoom());
	}

	TextPaintStyle DocumentMarkerPainter::ComputeTextPaintStyleFrom(
	const ComputedStyle& style,
	const TextMatchMarker& marker) {
	const Color text_color =
	LayoutTheme::GetTheme().PlatformTextSearchColor(marker.IsActiveMatch());
	if (style.VisitedDependentColor(GetCSSPropertyColor()) == text_color)
	return {};

	TextPaintStyle text_style;
	text_style.current_color = text_style.fill_color = text_style.stroke_color =
	text_style.emphasis_mark_color = text_color;
	text_style.stroke_width = style.TextStrokeWidth();
	text_style.shadow = nullptr;
	return text_style;
	}
	} // namespace blink