blob: 2979bce414092164abd86a87c930969a2d448155 [file] [log] [blame]
/*
* Copyright 2019 Google LLC
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "include/core/SkColor.h"
#include "include/core/SkFontStyle.h"
#include "include/core/SkPictureRecorder.h"
#include "include/core/SkString.h"
#include "modules/skparagraph/include/DartTypes.h"
#include "modules/skparagraph/include/Paragraph.h"
#include "modules/skparagraph/include/TextStyle.h"
#include "modules/skparagraph/include/TypefaceFontProvider.h"
#include "modules/skparagraph/src/ParagraphBuilderImpl.h"
#include "modules/skparagraph/src/ParagraphImpl.h"
#include <string>
#include <vector>
#include <emscripten.h>
#include <emscripten/bind.h>
#include "modules/canvaskit/WasmCommon.h"
using namespace emscripten;
namespace para = skia::textlayout;
SkColor4f toSkColor4f(WASMPointerF32 cPtr) {
float* fourFloats = reinterpret_cast<float*>(cPtr);
SkColor4f color = {fourFloats[0], fourFloats[1], fourFloats[2], fourFloats[3]};
return color;
}
struct SimpleFontStyle {
SkFontStyle::Slant slant;
SkFontStyle::Weight weight;
SkFontStyle::Width width;
};
struct SimpleTextStyle {
WASMPointerF32 colorPtr;
WASMPointerF32 foregroundColorPtr;
WASMPointerF32 backgroundColorPtr;
uint8_t decoration;
SkScalar decorationThickness;
WASMPointerF32 decorationColorPtr;
para::TextDecorationStyle decorationStyle;
para::TextBaseline textBaseline;
SkScalar fontSize;
SkScalar letterSpacing;
SkScalar wordSpacing;
SkScalar heightMultiplier;
bool halfLeading;
WASMPointerU8 localePtr;
int localeLen;
SimpleFontStyle fontStyle;
WASMPointerU8 fontFamiliesPtr;
int fontFamiliesLen;
int shadowLen;
WASMPointerF32 shadowColorsPtr;
WASMPointerF32 shadowOffsetsPtr;
WASMPointerF32 shadowBlurRadiiPtr;
int fontFeatureLen;
WASMPointerF32 fontFeatureNamesPtr;
WASMPointerF32 fontFeatureValuesPtr;
};
struct SimpleStrutStyle {
WASMPointerU32 fontFamiliesPtr;
int fontFamiliesLen;
SimpleFontStyle fontStyle;
SkScalar fontSize;
SkScalar heightMultiplier;
bool halfLeading;
SkScalar leading;
bool strutEnabled;
bool forceStrutHeight;
};
para::StrutStyle toStrutStyle(const SimpleStrutStyle& s) {
para::StrutStyle ss;
const char** fontFamilies = reinterpret_cast<const char**>(s.fontFamiliesPtr);
if (fontFamilies != nullptr) {
std::vector<SkString> ff;
for (int i = 0; i < s.fontFamiliesLen; i++) {
ff.emplace_back(fontFamilies[i]);
}
ss.setFontFamilies(ff);
}
SkFontStyle fs(s.fontStyle.weight, s.fontStyle.width, s.fontStyle.slant);
ss.setFontStyle(fs);
if (s.fontSize != 0) {
ss.setFontSize(s.fontSize);
}
if (s.heightMultiplier != 0) {
ss.setHeight(s.heightMultiplier);
ss.setHeightOverride(true);
}
ss.setHalfLeading(s.halfLeading);
if (s.leading != 0) {
ss.setLeading(s.leading);
}
ss.setStrutEnabled(s.strutEnabled);
ss.setForceStrutHeight(s.forceStrutHeight);
return ss;
}
para::TextStyle toTextStyle(const SimpleTextStyle& s) {
para::TextStyle ts;
// textstyle.color doesn't support a 4f color, however the foreground and background fields
// below do.
ts.setColor(toSkColor4f(s.colorPtr).toSkColor());
// It is functionally important that these paints be unset when no value was provided.
if (s.foregroundColorPtr) {
SkPaint p1;
p1.setColor4f(toSkColor4f(s.foregroundColorPtr));
ts.setForegroundColor(p1);
}
if (s.backgroundColorPtr) {
SkPaint p2;
p2.setColor4f(toSkColor4f(s.backgroundColorPtr));
ts.setBackgroundColor(p2);
}
if (s.fontSize != 0) {
ts.setFontSize(s.fontSize);
}
if (s.letterSpacing != 0) {
ts.setLetterSpacing(s.letterSpacing);
}
if (s.wordSpacing != 0) {
ts.setWordSpacing(s.wordSpacing);
}
if (s.heightMultiplier != 0) {
ts.setHeight(s.heightMultiplier);
ts.setHeightOverride(true);
}
ts.setHalfLeading(s.halfLeading);
ts.setDecoration(para::TextDecoration(s.decoration));
ts.setDecorationStyle(s.decorationStyle);
if (s.decorationThickness != 0) {
ts.setDecorationThicknessMultiplier(s.decorationThickness);
}
if (s.decorationColorPtr) {
ts.setDecorationColor(toSkColor4f(s.decorationColorPtr).toSkColor());
}
if (s.localeLen > 0) {
const char* localePtr = reinterpret_cast<const char*>(s.localePtr);
SkString lStr(localePtr, s.localeLen);
ts.setLocale(lStr);
}
const char** fontFamilies = reinterpret_cast<const char**>(s.fontFamiliesPtr);
if (fontFamilies != nullptr) {
std::vector<SkString> ff;
for (int i = 0; i < s.fontFamiliesLen; i++) {
ff.emplace_back(fontFamilies[i]);
}
ts.setFontFamilies(ff);
}
ts.setTextBaseline(s.textBaseline);
SkFontStyle fs(s.fontStyle.weight, s.fontStyle.width, s.fontStyle.slant);
ts.setFontStyle(fs);
if (s.shadowLen > 0) {
const SkColor4f* colors = reinterpret_cast<const SkColor4f*>(s.shadowColorsPtr);
const SkPoint* offsets = reinterpret_cast<const SkPoint*>(s.shadowOffsetsPtr);
const float* blurRadii = reinterpret_cast<const float*>(s.shadowBlurRadiiPtr);
for (int i = 0; i < s.shadowLen; i++) {
para::TextShadow shadow(colors[i].toSkColor(), offsets[i], blurRadii[i]);
ts.addShadow(shadow);
}
}
if (s.fontFeatureLen > 0) {
const char** fontFeatureNames = reinterpret_cast<const char**>(s.fontFeatureNamesPtr);
const int* fontFeatureValues = reinterpret_cast<const int*>(s.fontFeatureValuesPtr);
for (int i = 0; i < s.fontFeatureLen; i++) {
// Font features names are 4-character simple strings.
SkString name(fontFeatureNames[i], 4);
ts.addFontFeature(name, fontFeatureValues[i]);
}
}
return ts;
}
struct SimpleParagraphStyle {
bool disableHinting;
WASMPointerU8 ellipsisPtr;
size_t ellipsisLen;
SkScalar heightMultiplier;
size_t maxLines;
para::TextAlign textAlign;
para::TextDirection textDirection;
para::TextHeightBehavior textHeightBehavior;
SimpleTextStyle textStyle;
SimpleStrutStyle strutStyle;
};
para::ParagraphStyle toParagraphStyle(const SimpleParagraphStyle& s) {
para::ParagraphStyle ps;
if (s.disableHinting) {
ps.turnHintingOff();
}
if (s.ellipsisLen > 0) {
const char* ellipsisPtr = reinterpret_cast<const char*>(s.ellipsisPtr);
SkString eStr(ellipsisPtr, s.ellipsisLen);
ps.setEllipsis(eStr);
}
ps.setTextAlign(s.textAlign);
ps.setTextDirection(s.textDirection);
auto ts = toTextStyle(s.textStyle);
ps.setTextStyle(ts);
auto ss = toStrutStyle(s.strutStyle);
ps.setStrutStyle(ss);
if (s.heightMultiplier != 0) {
ps.setHeight(s.heightMultiplier);
}
if (s.maxLines != 0) {
ps.setMaxLines(s.maxLines);
}
ps.setTextHeightBehavior(s.textHeightBehavior);
return ps;
}
struct SimpleTextBox {
SkRect rect;
// This isn't the most efficient way to represent this, but it is much easier to keep
// everything as floats when unpacking on the JS side.
// 0.0 = RTL, 1.0 = LTr
SkScalar direction;
};
Float32Array TextBoxesToFloat32Array(std::vector<para::TextBox> boxes) {
// Pack these text boxes into an array of n groups of 5 SkScalar (floats)
if (!boxes.size()) {
return emscripten::val::null();
}
SimpleTextBox* rects = new SimpleTextBox[boxes.size()];
for (int i = 0; i < boxes.size(); i++) {
rects[i].rect = boxes[i].rect;
if (boxes[i].direction == para::TextDirection::kRtl) {
rects[i].direction = 0;
} else {
rects[i].direction = 1;
}
}
float* fPtr = reinterpret_cast<float*>(rects);
// Of note: now that we have cast rects to float*, emscripten is smart enough to wrap this
// into a Float32Array for us.
return Float32Array(typed_memory_view(boxes.size() * 5, fPtr));
}
Float32Array GetRectsForRange(para::Paragraph& self,
unsigned start,
unsigned end,
para::RectHeightStyle heightStyle,
para::RectWidthStyle widthStyle) {
std::vector<para::TextBox> boxes = self.getRectsForRange(start, end, heightStyle, widthStyle);
return TextBoxesToFloat32Array(boxes);
}
Float32Array GetRectsForPlaceholders(para::Paragraph& self) {
std::vector<para::TextBox> boxes = self.getRectsForPlaceholders();
return TextBoxesToFloat32Array(boxes);
}
JSArray GetLineMetrics(para::Paragraph& self) {
std::vector<skia::textlayout::LineMetrics> metrics;
self.getLineMetrics(metrics);
JSArray result = emscripten::val::array();
for (auto metric : metrics) {
JSObject m = emscripten::val::object();
m.set("startIndex", metric.fStartIndex);
m.set("endIndex", metric.fEndIndex);
m.set("endExcludingWhitespaces", metric.fEndExcludingWhitespaces);
m.set("endIncludingNewline", metric.fEndIncludingNewline);
m.set("isHardBreak", metric.fHardBreak);
m.set("ascent", metric.fAscent);
m.set("descent", metric.fDescent);
m.set("height", metric.fHeight);
m.set("width", metric.fWidth);
m.set("left", metric.fLeft);
m.set("baseline", metric.fBaseline);
m.set("lineNumber", metric.fLineNumber);
result.call<void>("push", m);
}
return result;
}
/*
* Returns Lines[]
*/
JSArray GetShapedLines(para::Paragraph& self) {
struct LineAccumulate {
int lineNumber = -1; // deliberately -1 from starting value
uint32_t minOffset = 0xFFFFFFFF;
uint32_t maxOffset = 0;
float minAscent = 0;
float maxDescent = 0;
// not really accumulated, but definitely set
float baseline = 0;
void reset(int lineNumber) {
new (this) LineAccumulate;
this->lineNumber = lineNumber;
}
};
// where we accumulate our js output
JSArray jlines = emscripten::val::array();
JSObject jline = emscripten::val::null();
JSArray jruns = emscripten::val::null();
LineAccumulate accum;
self.visit([&](int lineNumber, const para::Paragraph::VisitorInfo* info) {
if (!info) {
if (!jline) return; // how???
// end of current line
JSObject range = emscripten::val::object();
range.set("first", accum.minOffset);
range.set("last", accum.maxOffset);
jline.set("textRange", range);
jline.set("top", accum.baseline + accum.minAscent);
jline.set("bottom", accum.baseline + accum.maxDescent);
jline.set("baseline", accum.baseline);
return;
}
if (lineNumber != accum.lineNumber) {
SkASSERT(lineNumber == accum.lineNumber + 1); // assume monotonic
accum.reset(lineNumber);
jruns = emscripten::val::array();
jline = emscripten::val::object();
jline.set("runs", jruns);
// will assign textRange and metrics on end-of-line signal
jlines.call<void>("push", jline);
}
// append the run
const int N = info->count; // glyphs
const int N1 = N + 1; // positions, offsets have 1 extra (trailing) slot
JSObject jrun = emscripten::val::object();
jrun.set("flags", info->flags);
// TODO: figure out how to set a wrapped sk_sp<SkTypeface>
// jrun.set("typeface", info->font.getTypeface());
jrun.set("typeface", emscripten::val::null());
jrun.set("size", info->font.getSize());
if (info->font.getScaleX()) {
jrun.set("scaleX", info->font.getScaleX());
}
jrun.set("glyphs", MakeTypedArray(N, info->glyphs));
jrun.set("offsets", MakeTypedArray(N1, info->utf8Starts));
// we need to modify the positions, so make a temp copy
SkAutoSTMalloc<32, SkPoint> positions(N1);
for (int i = 0; i < N; ++i) {
positions.get()[i] = info->positions[i] + info->origin;
}
positions.get()[N] = { info->advanceX, positions.get()[N - 1].fY };
jrun.set("positions", MakeTypedArray(N1*2, (const float*)positions.get()));
jruns.call<void>("push", jrun);
// update accum
{ SkFontMetrics fm;
info->font.getMetrics(&fm);
accum.minAscent = std::min(accum.minAscent, fm.fAscent);
accum.maxDescent = std::max(accum.maxDescent, fm.fDescent);
accum.baseline = info->origin.fY;
accum.minOffset = std::min(accum.minOffset, info->utf8Starts[0]);
accum.maxOffset = std::max(accum.maxOffset, info->utf8Starts[N]);
}
});
return jlines;
}
EMSCRIPTEN_BINDINGS(Paragraph) {
class_<para::Paragraph>("Paragraph")
.function("didExceedMaxLines", &para::Paragraph::didExceedMaxLines)
.function("getAlphabeticBaseline", &para::Paragraph::getAlphabeticBaseline)
.function("getGlyphPositionAtCoordinate", &para::Paragraph::getGlyphPositionAtCoordinate)
.function("getHeight", &para::Paragraph::getHeight)
.function("getIdeographicBaseline", &para::Paragraph::getIdeographicBaseline)
.function("getLineMetrics", &GetLineMetrics)
.function("getLongestLine", &para::Paragraph::getLongestLine)
.function("getMaxIntrinsicWidth", &para::Paragraph::getMaxIntrinsicWidth)
.function("getMaxWidth", &para::Paragraph::getMaxWidth)
.function("getMinIntrinsicWidth", &para::Paragraph::getMinIntrinsicWidth)
.function("_getRectsForPlaceholders", &GetRectsForPlaceholders)
.function("_getRectsForRange", &GetRectsForRange)
.function("getShapedLines", &GetShapedLines)
.function("getWordBoundary", &para::Paragraph::getWordBoundary)
.function("layout", &para::Paragraph::layout);
class_<para::ParagraphBuilderImpl>("ParagraphBuilder")
.class_function(
"_Make",
optional_override([](SimpleParagraphStyle style, sk_sp<SkFontMgr> fontMgr)
-> std::unique_ptr<para::ParagraphBuilderImpl> {
auto fc = sk_make_sp<para::FontCollection>();
fc->setDefaultFontManager(fontMgr);
fc->enableFontFallback();
auto ps = toParagraphStyle(style);
auto pb = para::ParagraphBuilderImpl::make(ps, fc);
return std::unique_ptr<para::ParagraphBuilderImpl>(
static_cast<para::ParagraphBuilderImpl*>(pb.release()));
}),
allow_raw_pointers())
.class_function(
"_MakeFromFontProvider",
optional_override([](SimpleParagraphStyle style,
sk_sp<para::TypefaceFontProvider> fontProvider)
-> std::unique_ptr<para::ParagraphBuilderImpl> {
auto fc = sk_make_sp<para::FontCollection>();
fc->setDefaultFontManager(fontProvider);
fc->enableFontFallback();
auto ps = toParagraphStyle(style);
auto pb = para::ParagraphBuilderImpl::make(ps, fc);
return std::unique_ptr<para::ParagraphBuilderImpl>(
static_cast<para::ParagraphBuilderImpl*>(pb.release()));
}),
allow_raw_pointers())
.class_function(
"_ShapeText",
optional_override([](JSString jtext, JSArray jruns, float width) -> JSArray {
std::string textStorage = jtext.as<std::string>();
const char* text = textStorage.data();
size_t textCount = textStorage.size();
auto fc = sk_make_sp<para::FontCollection>();
fc->setDefaultFontManager(SkFontMgr::RefDefault());
fc->enableFontFallback();
para::ParagraphStyle pstyle;
{
// For the most part this is ignored, since we set an explicit TextStyle
// for all of our text runs, but it is required by SkParagraph.
para::TextStyle style;
style.setFontFamilies({SkString("sans-serif")});
style.setFontSize(32);
pstyle.setTextStyle(style);
}
auto pb = para::ParagraphBuilder::make(pstyle, fc);
// tease apart the FontBlock runs
size_t runCount = jruns["length"].as<size_t>();
for (size_t i = 0; i < runCount; ++i) {
emscripten::val r = jruns[i];
para::TextStyle style;
style.setTypeface(r["typeface"].as< sk_sp<SkTypeface> >());
style.setFontSize(r["size"].as<float>());
const size_t subTextCount = r["length"].as<size_t>();
if (subTextCount > textCount) {
return emscripten::val("block runs exceed text length!");
}
pb->pushStyle(style);
pb->addText(text, subTextCount);
pb->pop();
text += subTextCount;
textCount -= subTextCount;
}
if (textCount != 0) {
return emscripten::val("Didn't have enough block runs to cover text");
}
auto pa = pb->Build();
pa->layout(width);
// workaround until this is fixed in SkParagraph
{
SkPictureRecorder rec;
pa->paint(rec.beginRecording({0,0,9999,9999}), 0, 0);
}
return GetShapedLines(*pa);
}),
allow_raw_pointers())
.function("addText",
optional_override([](para::ParagraphBuilderImpl& self, std::string text) {
return self.addText(text.c_str(), text.length());
}))
.function("build", &para::ParagraphBuilderImpl::Build, allow_raw_pointers())
.function("pop", &para::ParagraphBuilderImpl::pop)
.function("reset", &para::ParagraphBuilderImpl::Reset, allow_raw_pointers())
.function("_pushStyle", optional_override([](para::ParagraphBuilderImpl& self,
SimpleTextStyle textStyle) {
auto ts = toTextStyle(textStyle);
self.pushStyle(ts);
}))
// A method of pushing a textStyle with paints instead of colors for foreground and
// background. Since SimpleTextStyle is a value object, it cannot contain paints, which
// are not primitives. This binding is here to accept them. Any color that is specified
// in the textStyle is overridden.
.function("_pushPaintStyle",
optional_override([](para::ParagraphBuilderImpl& self,
SimpleTextStyle textStyle, SkPaint foreground,
SkPaint background) {
auto ts = toTextStyle(textStyle);
ts.setForegroundColor(foreground);
ts.setBackgroundColor(background);
self.pushStyle(ts);
}))
.function("_addPlaceholder", optional_override([](para::ParagraphBuilderImpl& self,
SkScalar width,
SkScalar height,
para::PlaceholderAlignment alignment,
para::TextBaseline baseline,
SkScalar offset) {
para::PlaceholderStyle ps(width, height, alignment, baseline, offset);
self.addPlaceholder(ps);
}));
class_<para::TypefaceFontProvider, base<SkFontMgr>>("TypefaceFontProvider")
.smart_ptr<sk_sp<para::TypefaceFontProvider>>("sk_sp<TypefaceFontProvider>")
.class_function("Make", optional_override([]()-> sk_sp<para::TypefaceFontProvider> {
return sk_make_sp<para::TypefaceFontProvider>();
}))
.function("_registerFont", optional_override([](para::TypefaceFontProvider& self,
sk_sp<SkTypeface> typeface,
WASMPointerU8 familyPtr) {
const char* fPtr = reinterpret_cast<const char*>(familyPtr);
SkString fStr(fPtr);
self.registerTypeface(typeface, fStr);
}), allow_raw_pointers());
// These value objects make it easier to send data across the wire.
value_object<para::PositionWithAffinity>("PositionWithAffinity")
.field("pos", &para::PositionWithAffinity::position)
.field("affinity", &para::PositionWithAffinity::affinity);
value_object<SimpleFontStyle>("FontStyle")
.field("slant", &SimpleFontStyle::slant)
.field("weight", &SimpleFontStyle::weight)
.field("width", &SimpleFontStyle::width);
value_object<SimpleParagraphStyle>("ParagraphStyle")
.field("disableHinting", &SimpleParagraphStyle::disableHinting)
.field("_ellipsisPtr", &SimpleParagraphStyle::ellipsisPtr)
.field("_ellipsisLen", &SimpleParagraphStyle::ellipsisLen)
.field("heightMultiplier", &SimpleParagraphStyle::heightMultiplier)
.field("maxLines", &SimpleParagraphStyle::maxLines)
.field("textAlign", &SimpleParagraphStyle::textAlign)
.field("textDirection", &SimpleParagraphStyle::textDirection)
.field("textHeightBehavior", &SimpleParagraphStyle::textHeightBehavior)
.field("textStyle", &SimpleParagraphStyle::textStyle)
.field("strutStyle", &SimpleParagraphStyle::strutStyle);
value_object<SimpleStrutStyle>("StrutStyle")
.field("_fontFamiliesPtr", &SimpleStrutStyle::fontFamiliesPtr)
.field("_fontFamiliesLen", &SimpleStrutStyle::fontFamiliesLen)
.field("strutEnabled", &SimpleStrutStyle::strutEnabled)
.field("fontSize", &SimpleStrutStyle::fontSize)
.field("fontStyle", &SimpleStrutStyle::fontStyle)
.field("heightMultiplier", &SimpleStrutStyle::heightMultiplier)
.field("halfLeading", &SimpleStrutStyle::halfLeading)
.field("leading", &SimpleStrutStyle::leading)
.field("forceStrutHeight", &SimpleStrutStyle::forceStrutHeight);
value_object<SimpleTextStyle>("TextStyle")
.field("_colorPtr", &SimpleTextStyle::colorPtr)
.field("_foregroundColorPtr", &SimpleTextStyle::foregroundColorPtr)
.field("_backgroundColorPtr", &SimpleTextStyle::backgroundColorPtr)
.field("decoration", &SimpleTextStyle::decoration)
.field("decorationThickness", &SimpleTextStyle::decorationThickness)
.field("_decorationColorPtr", &SimpleTextStyle::decorationColorPtr)
.field("decorationStyle", &SimpleTextStyle::decorationStyle)
.field("_fontFamiliesPtr", &SimpleTextStyle::fontFamiliesPtr)
.field("_fontFamiliesLen", &SimpleTextStyle::fontFamiliesLen)
.field("fontSize", &SimpleTextStyle::fontSize)
.field("letterSpacing", &SimpleTextStyle::letterSpacing)
.field("wordSpacing", &SimpleTextStyle::wordSpacing)
.field("heightMultiplier", &SimpleTextStyle::heightMultiplier)
.field("halfLeading", &SimpleTextStyle::halfLeading)
.field("_localePtr", &SimpleTextStyle::localePtr)
.field("_localeLen", &SimpleTextStyle::localeLen)
.field("fontStyle", &SimpleTextStyle::fontStyle)
.field("_shadowLen", &SimpleTextStyle::shadowLen)
.field("_shadowColorsPtr", &SimpleTextStyle::shadowColorsPtr)
.field("_shadowOffsetsPtr", &SimpleTextStyle::shadowOffsetsPtr)
.field("_shadowBlurRadiiPtr", &SimpleTextStyle::shadowBlurRadiiPtr)
.field("_fontFeatureLen", &SimpleTextStyle::fontFeatureLen)
.field("_fontFeatureNamesPtr", &SimpleTextStyle::fontFeatureNamesPtr)
.field("_fontFeatureValuesPtr", &SimpleTextStyle::fontFeatureValuesPtr);
// The U stands for unsigned - we can't bind a generic/template object, so we have to specify it
// with the type we are using.
// TODO(kjlubick) make this a typedarray.
value_object<para::SkRange<size_t>>("URange")
.field("start", &para::SkRange<size_t>::start)
.field("end", &para::SkRange<size_t>::end);
// TextDecoration should be a const because they can be combined
constant("NoDecoration", int(para::TextDecoration::kNoDecoration));
constant("UnderlineDecoration", int(para::TextDecoration::kUnderline));
constant("OverlineDecoration", int(para::TextDecoration::kOverline));
constant("LineThroughDecoration", int(para::TextDecoration::kLineThrough));
}