| /* |
| * Copyright 2016 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #ifndef GrShape_DEFINED |
| #define GrShape_DEFINED |
| |
| #include "GrStyle.h" |
| #include "SkPath.h" |
| #include "SkPathPriv.h" |
| #include "SkRRect.h" |
| #include "SkTemplates.h" |
| #include "SkTLazy.h" |
| |
| /** |
| * Represents a geometric shape (rrect or path) and the GrStyle that it should be rendered with. |
| * It is possible to apply the style to the GrShape to produce a new GrShape where the geometry |
| * reflects the styling information (e.g. is stroked). It is also possible to apply just the |
| * path effect from the style. In this case the resulting shape will include any remaining |
| * stroking information that is to be applied after the path effect. |
| * |
| * Shapes can produce keys that represent only the geometry information, not the style. Note that |
| * when styling information is applied to produce a new shape then the style has been converted |
| * to geometric information and is included in the new shape's key. When the same style is applied |
| * to two shapes that reflect the same underlying geometry the computed keys of the stylized shapes |
| * will be the same. |
| * |
| * Currently this can only be constructed from a path, rect, or rrect though it can become a path |
| * applying style to the geometry. The idea is to expand this to cover most or all of the geometries |
| * that have SkCanvas::draw APIs. |
| */ |
| class GrShape { |
| public: |
| GrShape() : fType(Type::kEmpty) {} |
| |
| explicit GrShape(const SkPath& path) |
| : fType(Type::kPath) |
| , fPath(&path) { |
| this->attemptToReduceFromPath(); |
| } |
| |
| explicit GrShape(const SkRRect& rrect) |
| : fType(Type::kRRect) |
| , fRRect(rrect) |
| , fRRectIsInverted(false) { |
| fRRectStart = DefaultRRectDirAndStartIndex(rrect, false, &fRRectDir); |
| this->attemptToReduceFromRRect(); |
| } |
| |
| explicit GrShape(const SkRect& rect) |
| : fType(Type::kRRect) |
| , fRRect(SkRRect::MakeRect(rect)) |
| , fRRectIsInverted(false) { |
| fRRectStart = DefaultRectDirAndStartIndex(rect, false, &fRRectDir); |
| this->attemptToReduceFromRRect(); |
| } |
| |
| GrShape(const SkPath& path, const GrStyle& style) |
| : fType(Type::kPath) |
| , fPath(&path) |
| , fStyle(style) { |
| this->attemptToReduceFromPath(); |
| } |
| |
| GrShape(const SkRRect& rrect, const GrStyle& style) |
| : fType(Type::kRRect) |
| , fRRect(rrect) |
| , fRRectIsInverted(false) |
| , fStyle(style) { |
| fRRectStart = DefaultRRectDirAndStartIndex(rrect, style.hasPathEffect(), &fRRectDir); |
| this->attemptToReduceFromRRect(); |
| } |
| |
| GrShape(const SkRRect& rrect, SkPath::Direction dir, unsigned start, bool inverted, |
| const GrStyle& style) |
| : fType(Type::kRRect) |
| , fRRect(rrect) |
| , fRRectIsInverted(inverted) |
| , fStyle(style) { |
| if (style.pathEffect()) { |
| fRRectDir = dir; |
| fRRectStart = start; |
| if (fRRect.getType() == SkRRect::kRect_Type) { |
| fRRectStart = (fRRectStart + 1) & 0b110; |
| } else if (fRRect.getType() == SkRRect::kOval_Type) { |
| fRRectStart &= 0b110; |
| } |
| } else { |
| fRRectStart = DefaultRRectDirAndStartIndex(rrect, false, &fRRectDir); |
| } |
| this->attemptToReduceFromRRect(); |
| } |
| |
| GrShape(const SkRect& rect, const GrStyle& style) |
| : fType(Type::kRRect) |
| , fRRect(SkRRect::MakeRect(rect)) |
| , fRRectIsInverted(false) |
| , fStyle(style) { |
| fRRectStart = DefaultRectDirAndStartIndex(rect, style.hasPathEffect(), &fRRectDir); |
| this->attemptToReduceFromRRect(); |
| } |
| |
| GrShape(const SkPath& path, const SkPaint& paint) |
| : fType(Type::kPath) |
| , fPath(&path) |
| , fStyle(paint) { |
| this->attemptToReduceFromPath(); |
| } |
| |
| GrShape(const SkRRect& rrect, const SkPaint& paint) |
| : fType(Type::kRRect) |
| , fRRect(rrect) |
| , fRRectIsInverted(false) |
| , fStyle(paint) { |
| fRRectStart = DefaultRRectDirAndStartIndex(rrect, fStyle.hasPathEffect(), &fRRectDir); |
| this->attemptToReduceFromRRect(); |
| } |
| |
| GrShape(const SkRect& rect, const SkPaint& paint) |
| : fType(Type::kRRect) |
| , fRRect(SkRRect::MakeRect(rect)) |
| , fRRectIsInverted(false) |
| , fStyle(paint) { |
| fRRectStart = DefaultRectDirAndStartIndex(rect, fStyle.hasPathEffect(), &fRRectDir); |
| this->attemptToReduceFromRRect(); |
| } |
| |
| GrShape(const GrShape&); |
| GrShape& operator=(const GrShape& that); |
| |
| ~GrShape() { |
| if (Type::kPath == fType) { |
| fPath.reset(); |
| } |
| } |
| |
| const GrStyle& style() const { return fStyle; } |
| |
| /** |
| * Returns a shape that has either applied the path effect or path effect and stroking |
| * information from this shape's style to its geometry. Scale is used when approximating the |
| * output geometry and typically is computed from the view matrix |
| */ |
| GrShape applyStyle(GrStyle::Apply apply, SkScalar scale) { |
| return GrShape(*this, apply, scale); |
| } |
| |
| /** Returns the unstyled geometry as a rrect if possible. */ |
| bool asRRect(SkRRect* rrect, SkPath::Direction* dir, unsigned* start, bool* inverted) const { |
| if (Type::kRRect != fType) { |
| return false; |
| } |
| if (rrect) { |
| *rrect = fRRect; |
| } |
| if (dir) { |
| *dir = fRRectDir; |
| } |
| if (start) { |
| *start = fRRectStart; |
| } |
| if (inverted) { |
| *inverted = fRRectIsInverted; |
| } |
| return true; |
| } |
| |
| /** |
| * If the unstyled shape is a straight line segment, returns true and sets pts to the endpoints. |
| * An inverse filled line path is still considered a line. |
| */ |
| bool asLine(SkPoint pts[2]) const { |
| if (fType != Type::kPath) { |
| return false; |
| } |
| return fPath.get()->isLine(pts); |
| } |
| |
| /** Returns the unstyled geometry as a path. */ |
| void asPath(SkPath* out) const { |
| switch (fType) { |
| case Type::kEmpty: |
| out->reset(); |
| break; |
| case Type::kRRect: |
| out->reset(); |
| out->addRRect(fRRect, fRRectDir, fRRectStart); |
| if (fRRectIsInverted) { |
| out->setFillType(SkPath::kInverseWinding_FillType); |
| } |
| break; |
| case Type::kPath: |
| *out = *fPath.get(); |
| break; |
| } |
| } |
| |
| /** |
| * Returns whether the geometry is empty. Note that applying the style could produce a |
| * non-empty shape. |
| */ |
| bool isEmpty() const { return Type::kEmpty == fType; } |
| |
| /** |
| * Gets the bounds of the geometry without reflecting the shape's styling. This ignores |
| * the inverse fill nature of the geometry. |
| */ |
| const SkRect& bounds() const; |
| |
| /** |
| * Gets the bounds of the geometry reflecting the shape's styling (ignoring inverse fill |
| * status). |
| */ |
| void styledBounds(SkRect* bounds) const; |
| |
| /** |
| * Is it known that the unstyled geometry has no unclosed contours. This means that it will |
| * not have any caps if stroked (modulo the effect of any path effect). |
| */ |
| bool knownToBeClosed() const { |
| switch (fType) { |
| case Type::kEmpty: |
| return true; |
| case Type::kRRect: |
| return true; |
| case Type::kPath: |
| return false; |
| } |
| return false; |
| } |
| |
| uint32_t segmentMask() const { |
| switch (fType) { |
| case Type::kEmpty: |
| return 0; |
| case Type::kRRect: |
| if (fRRect.getType() == SkRRect::kOval_Type) { |
| return SkPath::kConic_SegmentMask; |
| } else if (fRRect.getType() == SkRRect::kRect_Type) { |
| return SkPath::kLine_SegmentMask; |
| } |
| return SkPath::kLine_SegmentMask | SkPath::kConic_SegmentMask; |
| case Type::kPath: |
| return fPath.get()->getSegmentMasks(); |
| } |
| return 0; |
| } |
| |
| /** |
| * Gets the size of the key for the shape represented by this GrShape (ignoring its styling). |
| * A negative value is returned if the shape has no key (shouldn't be cached). |
| */ |
| int unstyledKeySize() const; |
| |
| /** |
| * Writes unstyledKeySize() bytes into the provided pointer. Assumes that there is enough |
| * space allocated for the key and that unstyledKeySize() does not return a negative value |
| * for this shape. |
| */ |
| void writeUnstyledKey(uint32_t* key) const; |
| |
| private: |
| enum class Type { |
| kEmpty, |
| kRRect, |
| kPath, |
| }; |
| |
| /** Constructor used by the applyStyle() function */ |
| GrShape(const GrShape& parentShape, GrStyle::Apply, SkScalar scale); |
| |
| /** |
| * Determines the key we should inherit from the input shape's geometry and style when |
| * we are applying the style to create a new shape. |
| */ |
| void setInheritedKey(const GrShape& parentShape, GrStyle::Apply, SkScalar scale); |
| |
| void attemptToReduceFromPath() { |
| SkASSERT(Type::kPath == fType); |
| fType = AttemptToReduceFromPathImpl(*fPath.get(), &fRRect, &fRRectDir, &fRRectStart, |
| &fRRectIsInverted, fStyle.pathEffect(), |
| fStyle.strokeRec()); |
| if (Type::kPath != fType) { |
| fPath.reset(); |
| fInheritedKey.reset(0); |
| } |
| } |
| |
| void attemptToReduceFromRRect() { |
| SkASSERT(Type::kRRect == fType); |
| SkASSERT(!fInheritedKey.count()); |
| if (fRRectIsInverted) { |
| if (fStyle.isDashed()) { |
| // Dashing ignores the inverseness (currently). skbug.com/5421 |
| fRRectIsInverted = false; |
| } |
| } else if (fRRect.isEmpty()) { |
| fType = Type::kEmpty; |
| } |
| } |
| |
| static Type AttemptToReduceFromPathImpl(const SkPath& path, SkRRect* rrect, |
| SkPath::Direction* rrectDir, unsigned* rrectStart, |
| bool* rrectIsInverted, const SkPathEffect* pe, |
| const SkStrokeRec& strokeRec); |
| |
| static constexpr SkPath::Direction kDefaultRRectDir = SkPath::kCW_Direction; |
| static constexpr unsigned kDefaultRRectStart = 0; |
| |
| static unsigned DefaultRectDirAndStartIndex(const SkRect& rect, bool hasPathEffect, |
| SkPath::Direction* dir) { |
| *dir = kDefaultRRectDir; |
| // This comes from SkPath's interface. The default for adding a SkRect is counter clockwise |
| // beginning at index 0 (which happens to correspond to rrect index 0 or 7). |
| if (!hasPathEffect) { |
| // It doesn't matter what start we use, just be consistent to avoid redundant keys. |
| return kDefaultRRectStart; |
| } |
| // In SkPath a rect starts at index 0 by default. This is the top left corner. However, |
| // we store rects as rrects. RRects don't preserve the invertedness, but rather sort the |
| // rect edges. Thus, we may need to modify the rrect's start index to account for the sort. |
| bool swapX = rect.fLeft > rect.fRight; |
| bool swapY = rect.fTop > rect.fBottom; |
| if (swapX && swapY) { |
| // 0 becomes start index 2 and times 2 to convert from rect the rrect indices. |
| return 2 * 2; |
| } else if (swapX) { |
| *dir = SkPath::kCCW_Direction; |
| // 0 becomes start index 1 and times 2 to convert from rect the rrect indices. |
| return 2 * 1; |
| } else if (swapY) { |
| *dir = SkPath::kCCW_Direction; |
| // 0 becomes start index 3 and times 2 to convert from rect the rrect indices. |
| return 2 * 3; |
| } |
| return 0; |
| } |
| |
| static unsigned DefaultRRectDirAndStartIndex(const SkRRect& rrect, bool hasPathEffect, |
| SkPath::Direction* dir) { |
| // This comes from SkPath's interface. The default for adding a SkRRect to a path is |
| // clockwise beginning at starting index 6. |
| static constexpr unsigned kPathRRectStartIdx = 6; |
| *dir = kDefaultRRectDir; |
| if (!hasPathEffect) { |
| // It doesn't matter what start we use, just be consistent to avoid redundant keys. |
| return kDefaultRRectStart; |
| } |
| return kPathRRectStartIdx; |
| } |
| |
| Type fType; |
| SkRRect fRRect; |
| SkPath::Direction fRRectDir; |
| unsigned fRRectStart; |
| bool fRRectIsInverted; |
| SkTLazy<SkPath> fPath; |
| GrStyle fStyle; |
| SkAutoSTArray<8, uint32_t> fInheritedKey; |
| }; |
| #endif |
