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Use SkPath for wavy decorations for x5 improvements in performance.

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Change-Id: I371f525bb91c2d415d6af4f8ff047f43678e5ac3
This commit is contained in:
Gary Qian
2017-08-09 11:02:03 -07:00
parent 653a763327
commit 1c108c04dd
2 changed files with 144 additions and 158 deletions
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293
engine/src/flutter/src/paragraph.cc
View File

@@ -630,162 +630,157 @@ void Paragraph::PaintDecorations(SkCanvas* canvas,
double y,
size_t record_index) {
PaintRecord& record = records_[record_index];
if (record.style().decoration != TextDecoration::kNone) {
const SkPaint::FontMetrics& metrics = record.metrics();
SkPaint paint;
paint.setStyle(SkPaint::kStroke_Style);
if (record.style().decoration_color == SK_ColorTRANSPARENT) {
paint.setColor(record.style().color);
} else {
paint.setColor(record.style().decoration_color);
if (record.style().decoration == TextDecoration::kNone)
return;
const SkPaint::FontMetrics& metrics = record.metrics();
SkPaint paint;
paint.setStyle(SkPaint::kStroke_Style);
if (record.style().decoration_color == SK_ColorTRANSPARENT) {
paint.setColor(record.style().color);
} else {
paint.setColor(record.style().decoration_color);
}
paint.setAntiAlias(true);
// This is set to 2 for the double line style
int decoration_count = 1;
// Filled when drawing wavy decorations.
SkPath path;
double width = 0;
if (paragraph_style_.text_align == TextAlign::justify &&
record.line() != lines_ - 1) {
width = width_;
} else {
width = record.GetRunWidth();
}
paint.setStrokeWidth(
(SkToBool(metrics.fFlags & SkPaint::FontMetrics::FontMetricsFlags::
kUnderlineThicknessIsValid_Flag))
? metrics.fUnderlineThickness *
record.style().decoration_thickness_multiplier
// Backup value if the fUnderlineThickness metric is not available:
// Divide by 14pt as it is the default size.
: record.style().font_size / 14.0f *
record.style().decoration_thickness_multiplier);
// Setup the decorations.
switch (record.style().decoration_style) {
case TextDecorationStyle::kSolid: {
break;
}
paint.setAntiAlias(true);
// This is set to 2 for the double line style
int decoration_count = 1;
// Filled when drawing wavy decorations.
std::vector<WaveCoordinates> wave_coords;
double width = 0;
if (paragraph_style_.text_align == TextAlign::justify &&
record.line() != lines_ - 1) {
width = width_;
} else {
width = record.GetRunWidth();
case TextDecorationStyle::kDouble: {
decoration_count = 2;
break;
}
paint.setStrokeWidth(
(SkToBool(metrics.fFlags & SkPaint::FontMetrics::FontMetricsFlags::
kUnderlineThicknessIsValid_Flag))
? metrics.fUnderlineThickness
// Backup value if the fUnderlineThickness metric is not available:
// Divide by 14pt as it is the default size.
: record.style().font_size / 14.0f *
record.style().decoration_thickness_multiplier);
// Setup the decorations.
switch (record.style().decoration_style) {
case TextDecorationStyle::kSolid: {
break;
}
case TextDecorationStyle::kDouble: {
decoration_count = 2;
break;
}
// Note: the intervals are scaled by the thickness of the line, so it is
// possible to change spacing by changing the decoration_thickness
// property of TextStyle.
case TextDecorationStyle::kDotted: {
// Divide by 14pt as it is the default size.
const float scale = record.style().font_size / 14.0f;
const SkScalar intervals[] = {1.0f * scale, 1.5f * scale, 1.0f * scale,
1.5f * scale};
size_t count = sizeof(intervals) / sizeof(intervals[0]);
paint.setPathEffect(SkPathEffect::MakeCompose(
SkDashPathEffect::Make(intervals, count, 0.0f),
SkDiscretePathEffect::Make(0, 0)));
break;
}
// Note: the intervals are scaled by the thickness of the line, so it is
// possible to change spacing by changing the decoration_thickness
// property of TextStyle.
case TextDecorationStyle::kDashed: {
// Divide by 14pt as it is the default size.
const float scale = record.style().font_size / 14.0f;
const SkScalar intervals[] = {4.0f * scale, 2.0f * scale, 4.0f * scale,
2.0f * scale};
size_t count = sizeof(intervals) / sizeof(intervals[0]);
paint.setPathEffect(SkPathEffect::MakeCompose(
SkDashPathEffect::Make(intervals, count, 0.0f),
SkDiscretePathEffect::Make(0, 0)));
break;
}
case TextDecorationStyle::kWavy: {
int wave_count = 0;
double x_start = 0;
double y_top = -metrics.fUnderlineThickness;
double y_bottom = metrics.fUnderlineThickness;
while (x_start + metrics.fUnderlineThickness * 2 < width) {
wave_coords.push_back(
WaveCoordinates(x_start, wave_count % 2 == 0 ? y_bottom : y_top,
x_start + metrics.fUnderlineThickness * 2,
wave_count % 2 == 0 ? y_top : y_bottom));
x_start += metrics.fUnderlineThickness * 2;
++wave_count;
}
break;
}
// Note: the intervals are scaled by the thickness of the line, so it is
// possible to change spacing by changing the decoration_thickness
// property of TextStyle.
case TextDecorationStyle::kDotted: {
// Divide by 14pt as it is the default size.
const float scale = record.style().font_size / 14.0f;
const SkScalar intervals[] = {1.0f * scale, 1.5f * scale, 1.0f * scale,
1.5f * scale};
size_t count = sizeof(intervals) / sizeof(intervals[0]);
paint.setPathEffect(SkPathEffect::MakeCompose(
SkDashPathEffect::Make(intervals, count, 0.0f),
SkDiscretePathEffect::Make(0, 0)));
break;
}
// Draw the decorations.
// Use a for loop for "kDouble" decoration style
for (int i = 0; i < decoration_count; i++) {
double y_offset =
i * metrics.fUnderlineThickness * kDoubleDecorationSpacing;
double y_offset_original = y_offset;
// Underline
if (record.style().decoration & 0x1) {
y_offset +=
(SkToBool(metrics.fFlags & SkPaint::FontMetrics::FontMetricsFlags::
kUnderlinePositionIsValid_Flag))
? metrics.fUnderlinePosition
: metrics.fUnderlineThickness;
if (record.style().decoration_style != TextDecorationStyle::kWavy)
canvas->drawLine(x, y + y_offset, x + width, y + y_offset, paint);
else
PaintWavyDecoration(canvas, wave_coords, paint, x, y, y_offset,
width);
y_offset = y_offset_original;
}
// Overline
if (record.style().decoration & 0x2) {
y_offset -= metrics.fAscent;
if (record.style().decoration_style != TextDecorationStyle::kWavy)
canvas->drawLine(x, y - y_offset, x + width, y - y_offset, paint);
else
PaintWavyDecoration(canvas, wave_coords, paint, x, y, -y_offset,
width);
y_offset = y_offset_original;
}
// Strikethrough
if (record.style().decoration & 0x4) {
if (SkToBool(metrics.fFlags & SkPaint::FontMetrics::FontMetricsFlags::
kStrikeoutThicknessIsValid_Flag))
paint.setStrokeWidth(metrics.fStrikeoutThickness *
record.style().decoration_thickness_multiplier);
// Make sure the double line is "centered" vertically.
y_offset += (decoration_count - 1.0) * metrics.fUnderlineThickness *
kDoubleDecorationSpacing / -2.0;
y_offset +=
(SkToBool(metrics.fFlags & SkPaint::FontMetrics::FontMetricsFlags::
kStrikeoutThicknessIsValid_Flag))
? metrics.fStrikeoutPosition
// Backup value if the strikeoutposition metric is not
// available:
: metrics.fXHeight / -2.0;
if (record.style().decoration_style != TextDecorationStyle::kWavy)
canvas->drawLine(x, y + y_offset, x + width, y + y_offset, paint);
else
PaintWavyDecoration(canvas, wave_coords, paint, x, y, y_offset,
width);
y_offset = y_offset_original;
// Note: the intervals are scaled by the thickness of the line, so it is
// possible to change spacing by changing the decoration_thickness
// property of TextStyle.
case TextDecorationStyle::kDashed: {
// Divide by 14pt as it is the default size.
const float scale = record.style().font_size / 14.0f;
const SkScalar intervals[] = {4.0f * scale, 2.0f * scale, 4.0f * scale,
2.0f * scale};
size_t count = sizeof(intervals) / sizeof(intervals[0]);
paint.setPathEffect(SkPathEffect::MakeCompose(
SkDashPathEffect::Make(intervals, count, 0.0f),
SkDiscretePathEffect::Make(0, 0)));
break;
}
case TextDecorationStyle::kWavy: {
int wave_count = 0;
double x_start = 0;
double wavelength = metrics.fUnderlineThickness *
record.style().decoration_thickness_multiplier;
path.moveTo(x, y);
while (x_start + wavelength * 2 < width) {
path.rQuadTo(wavelength, wave_count % 2 != 0 ? wavelength : -wavelength,
wavelength * 2, 0);
x_start += wavelength * 2;
++wave_count;
}
break;
}
}
}
void Paragraph::PaintWavyDecoration(SkCanvas* canvas,
std::vector<WaveCoordinates> wave_coords,
SkPaint paint,
double x,
double y,
double y_offset,
double width) {
for (size_t i = 0; i < wave_coords.size(); ++i) {
WaveCoordinates coords = wave_coords[i];
canvas->drawLine(x + coords.x_start, y + y_offset + coords.y_start,
x + coords.x_end, y + y_offset + coords.y_end, paint);
// Draw the decorations.
// Use a for loop for "kDouble" decoration style
for (int i = 0; i < decoration_count; i++) {
double y_offset =
i * metrics.fUnderlineThickness * kDoubleDecorationSpacing;
double y_offset_original = y_offset;
// Underline
if (record.style().decoration & 0x1) {
y_offset +=
(SkToBool(metrics.fFlags & SkPaint::FontMetrics::FontMetricsFlags::
kUnderlinePositionIsValid_Flag))
? metrics.fUnderlinePosition
: metrics.fUnderlineThickness;
if (record.style().decoration_style != TextDecorationStyle::kWavy) {
canvas->drawLine(x, y + y_offset, x + width, y + y_offset, paint);
} else {
SkPath offsetPath = path;
offsetPath.offset(0, y_offset);
canvas->drawPath(offsetPath, paint);
}
y_offset = y_offset_original;
}
// Overline
if (record.style().decoration & 0x2) {
// We subtract fAscent here because for double overlines, we want the
// second line to be above, not below the first.
y_offset -= metrics.fAscent;
if (record.style().decoration_style != TextDecorationStyle::kWavy) {
canvas->drawLine(x, y - y_offset, x + width, y - y_offset, paint);
} else {
SkPath offsetPath = path;
offsetPath.offset(0, -y_offset);
canvas->drawPath(offsetPath, paint);
}
y_offset = y_offset_original;
}
// Strikethrough
if (record.style().decoration & 0x4) {
if (SkToBool(metrics.fFlags & SkPaint::FontMetrics::FontMetricsFlags::
kStrikeoutThicknessIsValid_Flag))
paint.setStrokeWidth(metrics.fStrikeoutThickness *
record.style().decoration_thickness_multiplier);
// Make sure the double line is "centered" vertically.
y_offset += (decoration_count - 1.0) * metrics.fUnderlineThickness *
kDoubleDecorationSpacing / -2.0;
y_offset +=
(SkToBool(metrics.fFlags & SkPaint::FontMetrics::FontMetricsFlags::
kStrikeoutThicknessIsValid_Flag))
? metrics.fStrikeoutPosition
// Backup value if the strikeoutposition metric is not
// available:
: metrics.fXHeight / -2.0;
if (record.style().decoration_style != TextDecorationStyle::kWavy) {
canvas->drawLine(x, y + y_offset, x + width, y + y_offset, paint);
} else {
SkPath offsetPath = path;
offsetPath.offset(0, y_offset);
canvas->drawPath(offsetPath, paint);
}
y_offset = y_offset_original;
}
}
}

9
engine/src/flutter/src/paragraph.h
View File

@@ -242,15 +242,6 @@ class Paragraph {
double y,
size_t record_index);
// Calculates wavy decorations and Draws them onto the canvas.
void PaintWavyDecoration(SkCanvas* canvas,
std::vector<WaveCoordinates> wave_coords,
SkPaint paint,
double x,
double y,
double y_offset,
double width);
void CalculateIntrinsicWidths();
FTL_DISALLOW_COPY_AND_ASSIGN(Paragraph);