| /* |
| * Copyright 2016 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include "SkCanvas.h" |
| #include "SkPath.h" |
| #include "SkSVGAttribute.h" |
| #include "SkSVGNode.h" |
| #include "SkSVGRenderContext.h" |
| #include "SkSVGTypes.h" |
| |
| namespace { |
| |
| SkScalar length_size_for_type(const SkSize& viewport, SkSVGLengthContext::LengthType t) { |
| switch (t) { |
| case SkSVGLengthContext::LengthType::kHorizontal: |
| return viewport.width(); |
| case SkSVGLengthContext::LengthType::kVertical: |
| return viewport.height(); |
| case SkSVGLengthContext::LengthType::kOther: |
| return SkScalarSqrt(viewport.width() * viewport.height()); |
| } |
| |
| SkASSERT(false); // Not reached. |
| return 0; |
| } |
| |
| // Multipliers for DPI-relative units. |
| constexpr SkScalar kINMultiplier = 1.00f; |
| constexpr SkScalar kPTMultiplier = kINMultiplier / 72.272f; |
| constexpr SkScalar kPCMultiplier = kPTMultiplier * 12; |
| constexpr SkScalar kMMMultiplier = kINMultiplier / 25.4f; |
| constexpr SkScalar kCMMultiplier = kMMMultiplier * 10; |
| |
| } // anonymous ns |
| |
| SkScalar SkSVGLengthContext::resolve(const SkSVGLength& l, LengthType t) const { |
| switch (l.unit()) { |
| case SkSVGLength::Unit::kNumber: |
| // Fall through. |
| case SkSVGLength::Unit::kPX: |
| return l.value(); |
| case SkSVGLength::Unit::kPercentage: |
| return l.value() * length_size_for_type(fViewport, t) / 100; |
| case SkSVGLength::Unit::kCM: |
| return l.value() * fDPI * kCMMultiplier; |
| case SkSVGLength::Unit::kMM: |
| return l.value() * fDPI * kMMMultiplier; |
| case SkSVGLength::Unit::kIN: |
| return l.value() * fDPI * kINMultiplier; |
| case SkSVGLength::Unit::kPT: |
| return l.value() * fDPI * kPTMultiplier; |
| case SkSVGLength::Unit::kPC: |
| return l.value() * fDPI * kPCMultiplier; |
| default: |
| SkDebugf("unsupported unit type: <%d>\n", l.unit()); |
| return 0; |
| } |
| } |
| |
| SkRect SkSVGLengthContext::resolveRect(const SkSVGLength& x, const SkSVGLength& y, |
| const SkSVGLength& w, const SkSVGLength& h) const { |
| return SkRect::MakeXYWH( |
| this->resolve(x, SkSVGLengthContext::LengthType::kHorizontal), |
| this->resolve(y, SkSVGLengthContext::LengthType::kVertical), |
| this->resolve(w, SkSVGLengthContext::LengthType::kHorizontal), |
| this->resolve(h, SkSVGLengthContext::LengthType::kVertical)); |
| } |
| |
| namespace { |
| |
| SkPaint::Cap toSkCap(const SkSVGLineCap& cap) { |
| switch (cap.type()) { |
| case SkSVGLineCap::Type::kButt: |
| return SkPaint::kButt_Cap; |
| case SkSVGLineCap::Type::kRound: |
| return SkPaint::kRound_Cap; |
| case SkSVGLineCap::Type::kSquare: |
| return SkPaint::kSquare_Cap; |
| default: |
| SkASSERT(false); |
| return SkPaint::kButt_Cap; |
| } |
| } |
| |
| SkPaint::Join toSkJoin(const SkSVGLineJoin& join) { |
| switch (join.type()) { |
| case SkSVGLineJoin::Type::kMiter: |
| return SkPaint::kMiter_Join; |
| case SkSVGLineJoin::Type::kRound: |
| return SkPaint::kRound_Join; |
| case SkSVGLineJoin::Type::kBevel: |
| return SkPaint::kBevel_Join; |
| default: |
| SkASSERT(false); |
| return SkPaint::kMiter_Join; |
| } |
| } |
| |
| void applySvgPaint(const SkSVGRenderContext& ctx, const SkSVGPaint& svgPaint, SkPaint* p) { |
| switch (svgPaint.type()) { |
| case SkSVGPaint::Type::kColor: |
| p->setColor(SkColorSetA(svgPaint.color(), p->getAlpha())); |
| break; |
| case SkSVGPaint::Type::kIRI: { |
| const auto* node = ctx.findNodeById(svgPaint.iri()); |
| if (!node || !node->asPaint(ctx, p)) { |
| p->setColor(SK_ColorTRANSPARENT); |
| } |
| break; |
| } |
| case SkSVGPaint::Type::kCurrentColor: |
| SkDebugf("unimplemented 'currentColor' paint type"); |
| // Fall through. |
| case SkSVGPaint::Type::kNone: |
| // Fall through. |
| case SkSVGPaint::Type::kInherit: |
| break; |
| } |
| } |
| |
| inline uint8_t opacity_to_alpha(SkScalar o) { |
| return SkTo<uint8_t>(SkScalarRoundToInt(o * 255)); |
| } |
| |
| // Commit the selected attribute to the paint cache. |
| template <SkSVGAttribute> |
| void commitToPaint(const SkSVGPresentationAttributes&, |
| const SkSVGRenderContext&, |
| SkSVGPresentationContext*); |
| |
| template <> |
| void commitToPaint<SkSVGAttribute::kFill>(const SkSVGPresentationAttributes& attrs, |
| const SkSVGRenderContext& ctx, |
| SkSVGPresentationContext* pctx) { |
| applySvgPaint(ctx, *attrs.fFill.get(), &pctx->fFillPaint); |
| } |
| |
| template <> |
| void commitToPaint<SkSVGAttribute::kStroke>(const SkSVGPresentationAttributes& attrs, |
| const SkSVGRenderContext& ctx, |
| SkSVGPresentationContext* pctx) { |
| applySvgPaint(ctx, *attrs.fStroke.get(), &pctx->fStrokePaint); |
| } |
| |
| template <> |
| void commitToPaint<SkSVGAttribute::kFillOpacity>(const SkSVGPresentationAttributes& attrs, |
| const SkSVGRenderContext&, |
| SkSVGPresentationContext* pctx) { |
| pctx->fFillPaint.setAlpha(opacity_to_alpha(*attrs.fFillOpacity.get())); |
| } |
| |
| template <> |
| void commitToPaint<SkSVGAttribute::kStrokeLineCap>(const SkSVGPresentationAttributes& attrs, |
| const SkSVGRenderContext&, |
| SkSVGPresentationContext* pctx) { |
| const auto& cap = *attrs.fStrokeLineCap.get(); |
| if (cap.type() != SkSVGLineCap::Type::kInherit) { |
| pctx->fStrokePaint.setStrokeCap(toSkCap(cap)); |
| } |
| } |
| |
| template <> |
| void commitToPaint<SkSVGAttribute::kStrokeLineJoin>(const SkSVGPresentationAttributes& attrs, |
| const SkSVGRenderContext&, |
| SkSVGPresentationContext* pctx) { |
| const auto& join = *attrs.fStrokeLineJoin.get(); |
| if (join.type() != SkSVGLineJoin::Type::kInherit) { |
| pctx->fStrokePaint.setStrokeJoin(toSkJoin(join)); |
| } |
| } |
| |
| template <> |
| void commitToPaint<SkSVGAttribute::kStrokeOpacity>(const SkSVGPresentationAttributes& attrs, |
| const SkSVGRenderContext&, |
| SkSVGPresentationContext* pctx) { |
| pctx->fStrokePaint.setAlpha(opacity_to_alpha(*attrs.fStrokeOpacity.get())); |
| } |
| |
| template <> |
| void commitToPaint<SkSVGAttribute::kStrokeWidth>(const SkSVGPresentationAttributes& attrs, |
| const SkSVGRenderContext& ctx, |
| SkSVGPresentationContext* pctx) { |
| auto strokeWidth = ctx.lengthContext().resolve(*attrs.fStrokeWidth.get(), |
| SkSVGLengthContext::LengthType::kOther); |
| pctx->fStrokePaint.setStrokeWidth(strokeWidth); |
| } |
| |
| template <> |
| void commitToPaint<SkSVGAttribute::kFillRule>(const SkSVGPresentationAttributes&, |
| const SkSVGRenderContext&, |
| SkSVGPresentationContext*) { |
| // Not part of the SkPaint state; applied to the path at render time. |
| } |
| |
| } // anonymous ns |
| |
| SkSVGPresentationContext::SkSVGPresentationContext() |
| : fInherited(SkSVGPresentationAttributes::MakeInitial()) { |
| |
| fFillPaint.setStyle(SkPaint::kFill_Style); |
| fStrokePaint.setStyle(SkPaint::kStroke_Style); |
| |
| // TODO: drive AA off presentation attrs also (shape-rendering?) |
| fFillPaint.setAntiAlias(true); |
| fStrokePaint.setAntiAlias(true); |
| |
| // Commit initial values to the paint cache. |
| SkCanvas dummyCanvas(0, 0); |
| SkSVGRenderContext dummy(&dummyCanvas, SkSVGIDMapper(), SkSVGLengthContext(SkSize::Make(0, 0)), |
| *this); |
| |
| commitToPaint<SkSVGAttribute::kFill>(fInherited, dummy, this); |
| commitToPaint<SkSVGAttribute::kFillOpacity>(fInherited, dummy, this); |
| commitToPaint<SkSVGAttribute::kStroke>(fInherited, dummy, this); |
| commitToPaint<SkSVGAttribute::kStrokeLineCap>(fInherited, dummy, this); |
| commitToPaint<SkSVGAttribute::kStrokeLineJoin>(fInherited, dummy, this); |
| commitToPaint<SkSVGAttribute::kStrokeOpacity>(fInherited, dummy, this); |
| commitToPaint<SkSVGAttribute::kStrokeWidth>(fInherited, dummy, this); |
| } |
| |
| SkSVGRenderContext::SkSVGRenderContext(SkCanvas* canvas, |
| const SkSVGIDMapper& mapper, |
| const SkSVGLengthContext& lctx, |
| const SkSVGPresentationContext& pctx) |
| : fIDMapper(mapper) |
| , fLengthContext(lctx) |
| , fPresentationContext(pctx) |
| , fCanvas(canvas) |
| , fCanvasSaveCount(canvas->getSaveCount()) {} |
| |
| SkSVGRenderContext::SkSVGRenderContext(const SkSVGRenderContext& other) |
| : SkSVGRenderContext(other.fCanvas, |
| other.fIDMapper, |
| *other.fLengthContext, |
| *other.fPresentationContext) {} |
| |
| SkSVGRenderContext::~SkSVGRenderContext() { |
| fCanvas->restoreToCount(fCanvasSaveCount); |
| } |
| |
| const SkSVGNode* SkSVGRenderContext::findNodeById(const SkString& id) const { |
| const auto* v = fIDMapper.find(id); |
| return v ? v->get() : nullptr; |
| } |
| |
| void SkSVGRenderContext::applyPresentationAttributes(const SkSVGPresentationAttributes& attrs, |
| uint32_t flags) { |
| |
| #define ApplyLazyInheritedAttribute(ATTR) \ |
| do { \ |
| /* All attributes should be defined on the inherited context. */ \ |
| SkASSERT(fPresentationContext->fInherited.f ## ATTR.isValid()); \ |
| const auto* value = attrs.f ## ATTR.getMaybeNull(); \ |
| if (value && *value != *fPresentationContext->fInherited.f ## ATTR.get()) { \ |
| /* Update the local attribute value */ \ |
| fPresentationContext.writable()->fInherited.f ## ATTR.set(*value); \ |
| /* Update the cached paints */ \ |
| commitToPaint<SkSVGAttribute::k ## ATTR>(attrs, *this, \ |
| fPresentationContext.writable()); \ |
| } \ |
| } while (false) |
| |
| ApplyLazyInheritedAttribute(Fill); |
| ApplyLazyInheritedAttribute(FillOpacity); |
| ApplyLazyInheritedAttribute(FillRule); |
| ApplyLazyInheritedAttribute(Stroke); |
| ApplyLazyInheritedAttribute(StrokeLineCap); |
| ApplyLazyInheritedAttribute(StrokeLineJoin); |
| ApplyLazyInheritedAttribute(StrokeOpacity); |
| ApplyLazyInheritedAttribute(StrokeWidth); |
| |
| #undef ApplyLazyInheritedAttribute |
| |
| // Uninherited attributes. Only apply to the current context. |
| |
| if (auto* opacity = attrs.fOpacity.getMaybeNull()) { |
| this->applyOpacity(opacity->value(), flags); |
| } |
| |
| if (auto* clip = attrs.fClipPath.getMaybeNull()) { |
| this->applyClip(*clip); |
| } |
| } |
| |
| void SkSVGRenderContext::applyOpacity(SkScalar opacity, uint32_t flags) { |
| if (opacity >= 1) { |
| return; |
| } |
| |
| const bool hasFill = SkToBool(this->fillPaint()); |
| const bool hasStroke = SkToBool(this->strokePaint()); |
| |
| // We can apply the opacity as paint alpha iif it only affects one atomic draw. |
| // For now, this means a) the target node doesn't have any descendants, and |
| // b) it only has a stroke or a fill (but not both). Going forward, we may need |
| // to refine this heuristic (e.g. to accommodate markers). |
| if ((flags & kLeaf) && (hasFill ^ hasStroke)) { |
| auto* pctx = fPresentationContext.writable(); |
| if (hasFill) { |
| pctx->fFillPaint.setAlpha( |
| SkScalarRoundToInt(opacity * pctx->fFillPaint.getAlpha())); |
| } else { |
| pctx->fStrokePaint.setAlpha( |
| SkScalarRoundToInt(opacity * pctx->fStrokePaint.getAlpha())); |
| } |
| } else { |
| // Expensive, layer-based fall back. |
| SkPaint opacityPaint; |
| opacityPaint.setAlpha(opacity_to_alpha(opacity)); |
| // Balanced in the destructor, via restoreToCount(). |
| fCanvas->saveLayer(nullptr, &opacityPaint); |
| } |
| } |
| |
| void SkSVGRenderContext::applyClip(const SkSVGClip& clip) { |
| if (clip.type() != SkSVGClip::Type::kIRI) { |
| return; |
| } |
| |
| const SkSVGNode* clipNode = this->findNodeById(clip.iri()); |
| if (!clipNode || clipNode->tag() != SkSVGTag::kClipPath) { |
| return; |
| } |
| |
| const SkPath clipPath = clipNode->asPath(*this); |
| |
| // We use the computed clip path in two ways: |
| // |
| // - apply to the current canvas, for drawing |
| // - track in the presentation context, for asPath() composition |
| // |
| // TODO: the two uses are exclusive, avoid canvas churn when non needed. |
| |
| // Only save if needed |
| if (fCanvas->getSaveCount() == fCanvasSaveCount) { |
| fCanvas->save(); |
| } |
| |
| fCanvas->clipPath(clipPath, true); |
| fClipPath.set(clipPath); |
| } |
| |
| const SkPaint* SkSVGRenderContext::fillPaint() const { |
| const SkSVGPaint::Type paintType = fPresentationContext->fInherited.fFill.get()->type(); |
| return paintType != SkSVGPaint::Type::kNone ? &fPresentationContext->fFillPaint : nullptr; |
| } |
| |
| const SkPaint* SkSVGRenderContext::strokePaint() const { |
| const SkSVGPaint::Type paintType = fPresentationContext->fInherited.fStroke.get()->type(); |
| return paintType != SkSVGPaint::Type::kNone ? &fPresentationContext->fStrokePaint : nullptr; |
| } |