/* * 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 #include #include #include #include "modules/canvaskit/WasmCommon.h" using namespace emscripten; namespace para = skia::textlayout; SkColor4f toSkColor4f(WASMPointerF32 cPtr) { float* fourFloats = reinterpret_cast(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(s.fontFamiliesPtr); if (fontFamilies != nullptr) { std::vector 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(s.localePtr); SkString lStr(localePtr, s.localeLen); ts.setLocale(lStr); } const char** fontFamilies = reinterpret_cast(s.fontFamiliesPtr); if (fontFamilies != nullptr) { std::vector 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(s.shadowColorsPtr); const SkPoint* offsets = reinterpret_cast(s.shadowOffsetsPtr); const float* blurRadii = reinterpret_cast(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(s.fontFeatureNamesPtr); const int* fontFeatureValues = reinterpret_cast(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(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 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(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 boxes = self.getRectsForRange(start, end, heightStyle, widthStyle); return TextBoxesToFloat32Array(boxes); } Float32Array GetRectsForPlaceholders(para::Paragraph& self) { std::vector boxes = self.getRectsForPlaceholders(); return TextBoxesToFloat32Array(boxes); } JSArray GetLineMetrics(para::Paragraph& self) { std::vector 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("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("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 // 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("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_("Paragraph") .function("didExceedMaxLines", ¶::Paragraph::didExceedMaxLines) .function("getAlphabeticBaseline", ¶::Paragraph::getAlphabeticBaseline) .function("getGlyphPositionAtCoordinate", ¶::Paragraph::getGlyphPositionAtCoordinate) .function("getHeight", ¶::Paragraph::getHeight) .function("getIdeographicBaseline", ¶::Paragraph::getIdeographicBaseline) .function("getLineMetrics", &GetLineMetrics) .function("getLongestLine", ¶::Paragraph::getLongestLine) .function("getMaxIntrinsicWidth", ¶::Paragraph::getMaxIntrinsicWidth) .function("getMaxWidth", ¶::Paragraph::getMaxWidth) .function("getMinIntrinsicWidth", ¶::Paragraph::getMinIntrinsicWidth) .function("_getRectsForPlaceholders", &GetRectsForPlaceholders) .function("_getRectsForRange", &GetRectsForRange) .function("getShapedLines", &GetShapedLines) .function("getWordBoundary", ¶::Paragraph::getWordBoundary) .function("layout", ¶::Paragraph::layout); class_("ParagraphBuilder") .class_function( "_Make", optional_override([](SimpleParagraphStyle style, sk_sp fontMgr) -> std::unique_ptr { auto fc = sk_make_sp(); fc->setDefaultFontManager(fontMgr); fc->enableFontFallback(); auto ps = toParagraphStyle(style); auto pb = para::ParagraphBuilderImpl::make(ps, fc); return std::unique_ptr( static_cast(pb.release())); }), allow_raw_pointers()) .class_function( "_MakeFromFontProvider", optional_override([](SimpleParagraphStyle style, sk_sp fontProvider) -> std::unique_ptr { auto fc = sk_make_sp(); fc->setDefaultFontManager(fontProvider); fc->enableFontFallback(); auto ps = toParagraphStyle(style); auto pb = para::ParagraphBuilderImpl::make(ps, fc); return std::unique_ptr( static_cast(pb.release())); }), allow_raw_pointers()) .class_function( "_ShapeText", optional_override([](JSString jtext, JSArray jruns, float width) -> JSArray { std::string textStorage = jtext.as(); const char* text = textStorage.data(); size_t textCount = textStorage.size(); auto fc = sk_make_sp(); 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(); for (size_t i = 0; i < runCount; ++i) { emscripten::val r = jruns[i]; para::TextStyle style; style.setTypeface(r["typeface"].as< sk_sp >()); style.setFontSize(r["size"].as()); const size_t subTextCount = r["length"].as(); 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", ¶::ParagraphBuilderImpl::Build, allow_raw_pointers()) .function("pop", ¶::ParagraphBuilderImpl::pop) .function("reset", ¶::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_>("TypefaceFontProvider") .smart_ptr>("sk_sp") .class_function("Make", optional_override([]()-> sk_sp { return sk_make_sp(); })) .function("_registerFont", optional_override([](para::TypefaceFontProvider& self, sk_sp typeface, WASMPointerU8 familyPtr) { const char* fPtr = reinterpret_cast(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("PositionWithAffinity") .field("pos", ¶::PositionWithAffinity::position) .field("affinity", ¶::PositionWithAffinity::affinity); value_object("FontStyle") .field("slant", &SimpleFontStyle::slant) .field("weight", &SimpleFontStyle::weight) .field("width", &SimpleFontStyle::width); value_object("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("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("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>("URange") .field("start", ¶::SkRange::start) .field("end", ¶::SkRange::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)); }