| /* |
| * 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() { this->initType(Type::kEmpty); } |
| |
| explicit GrShape(const SkPath& path) : GrShape(path, GrStyle::SimpleFill()) {} |
| |
| explicit GrShape(const SkRRect& rrect) : GrShape(rrect, GrStyle::SimpleFill()) {} |
| |
| explicit GrShape(const SkRect& rect) : GrShape(rect, GrStyle::SimpleFill()) {} |
| |
| GrShape(const SkPath& path, const GrStyle& style) : fStyle(style) { |
| this->initType(Type::kPath, &path); |
| this->attemptToSimplifyPath(); |
| } |
| |
| GrShape(const SkRRect& rrect, const GrStyle& style) |
| : fStyle(style) { |
| this->initType(Type::kRRect); |
| fRRectData.fRRect = rrect; |
| fRRectData.fInverted = false; |
| fRRectData.fStart = DefaultRRectDirAndStartIndex(rrect, style.hasPathEffect(), |
| &fRRectData.fDir); |
| this->attemptToSimplifyRRect(); |
| } |
| |
| GrShape(const SkRRect& rrect, SkPath::Direction dir, unsigned start, bool inverted, |
| const GrStyle& style) |
| : fStyle(style) { |
| this->initType(Type::kRRect); |
| fRRectData.fRRect = rrect; |
| fRRectData.fInverted = inverted; |
| if (style.pathEffect()) { |
| fRRectData.fDir = dir; |
| fRRectData.fStart = start; |
| if (fRRectData.fRRect.getType() == SkRRect::kRect_Type) { |
| fRRectData.fStart = (fRRectData.fStart + 1) & 0b110; |
| } else if (fRRectData.fRRect.getType() == SkRRect::kOval_Type) { |
| fRRectData.fStart &= 0b110; |
| } |
| } else { |
| fRRectData.fStart = DefaultRRectDirAndStartIndex(rrect, false, &fRRectData.fDir); |
| } |
| this->attemptToSimplifyRRect(); |
| } |
| |
| GrShape(const SkRect& rect, const GrStyle& style) |
| : fStyle(style) { |
| this->initType(Type::kRRect); |
| fRRectData.fRRect = SkRRect::MakeRect(rect); |
| fRRectData.fInverted = false; |
| fRRectData.fStart = DefaultRectDirAndStartIndex(rect, style.hasPathEffect(), |
| &fRRectData.fDir); |
| this->attemptToSimplifyRRect(); |
| } |
| |
| GrShape(const SkPath& path, const SkPaint& paint) : fStyle(paint) { |
| this->initType(Type::kPath, &path); |
| this->attemptToSimplifyPath(); |
| } |
| |
| GrShape(const SkRRect& rrect, const SkPaint& paint) |
| : fStyle(paint) { |
| this->initType(Type::kRRect); |
| fRRectData.fRRect = rrect; |
| fRRectData.fInverted = false; |
| fRRectData.fStart = DefaultRRectDirAndStartIndex(rrect, fStyle.hasPathEffect(), |
| &fRRectData.fDir); |
| this->attemptToSimplifyRRect(); |
| } |
| |
| GrShape(const SkRect& rect, const SkPaint& paint) |
| : fStyle(paint) { |
| this->initType(Type::kRRect); |
| fRRectData.fRRect = SkRRect::MakeRect(rect); |
| fRRectData.fInverted = false; |
| fRRectData.fStart = DefaultRectDirAndStartIndex(rect, fStyle.hasPathEffect(), |
| &fRRectData.fDir); |
| this->attemptToSimplifyRRect(); |
| } |
| |
| GrShape(const GrShape&); |
| GrShape& operator=(const GrShape& that); |
| |
| ~GrShape() { this->changeType(Type::kEmpty); } |
| |
| 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) const { |
| 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 = fRRectData.fRRect; |
| } |
| if (dir) { |
| *dir = fRRectData.fDir; |
| } |
| if (start) { |
| *start = fRRectData.fStart; |
| } |
| if (inverted) { |
| *inverted = fRRectData.fInverted; |
| } |
| 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 this->path().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(fRRectData.fRRect, fRRectData.fDir, fRRectData.fStart); |
| // Below matches the fill type that attemptToSimplifyPath uses. |
| if (fRRectData.fInverted) { |
| out->setFillType(kDefaultPathInverseFillType); |
| } else { |
| out->setFillType(kDefaultPathFillType); |
| } |
| break; |
| case Type::kPath: |
| *out = this->path(); |
| 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 this shape known to be convex, before styling is applied. An unclosed but otherwise |
| * convex path is considered to be closed if they styling reflects a fill and not otherwise. |
| * This is because filling closes all contours in the path. |
| */ |
| bool knownToBeConvex() const { |
| switch (fType) { |
| case Type::kEmpty: |
| return true; |
| case Type::kRRect: |
| return true; |
| case Type::kPath: |
| // SkPath.isConvex() really means "is this path convex were it to be closed" and |
| // thus doesn't give the correct answer for stroked paths, hence we also check |
| // whether the path is either filled or closed. Convex paths may only have one |
| // contour hence isLastContourClosed() is a sufficient for a convex path. |
| return (this->style().isSimpleFill() || this->path().isLastContourClosed()) && |
| this->path().isConvex(); |
| } |
| return false; |
| } |
| |
| /** Is the pre-styled geometry inverse filled? */ |
| bool inverseFilled() const { |
| bool ret = false; |
| switch (fType) { |
| case Type::kEmpty: |
| ret = false; |
| break; |
| case Type::kRRect: |
| ret = fRRectData.fInverted; |
| break; |
| case Type::kPath: |
| ret = this->path().isInverseFillType(); |
| break; |
| } |
| // Dashing ignores inverseness. We should have caught this earlier. skbug.com/5421 |
| SkASSERT(!(ret && this->style().isDashed())); |
| return ret; |
| } |
| |
| /** |
| * Might applying the styling to the geometry produce an inverse fill. The "may" part comes in |
| * because an arbitrary path effect could produce an inverse filled path. In other cases this |
| * can be thought of as "inverseFilledAfterStyling()". |
| */ |
| bool mayBeInverseFilledAfterStyling() const { |
| // An arbitrary path effect can produce an arbitrary output path, which may be inverse |
| // filled. |
| if (this->style().hasNonDashPathEffect()) { |
| return true; |
| } |
| return this->inverseFilled(); |
| } |
| |
| /** |
| * 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: |
| // SkPath doesn't keep track of the closed status of each contour. |
| return SkPathPriv::IsClosedSingleContour(this->path()); |
| } |
| return false; |
| } |
| |
| uint32_t segmentMask() const { |
| switch (fType) { |
| case Type::kEmpty: |
| return 0; |
| case Type::kRRect: |
| if (fRRectData.fRRect.getType() == SkRRect::kOval_Type) { |
| return SkPath::kConic_SegmentMask; |
| } else if (fRRectData.fRRect.getType() == SkRRect::kRect_Type) { |
| return SkPath::kLine_SegmentMask; |
| } |
| return SkPath::kLine_SegmentMask | SkPath::kConic_SegmentMask; |
| case Type::kPath: |
| return this->path().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; |
| |
| bool hasUnstyledKey() const { return this->unstyledKeySize() >= 0; } |
| |
| /** |
| * 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, |
| }; |
| |
| void initType(Type type, const SkPath* path = nullptr) { |
| fType = Type::kEmpty; |
| this->changeType(type, path); |
| } |
| |
| void changeType(Type type, const SkPath* path = nullptr) { |
| bool wasPath = Type::kPath == fType; |
| fType = type; |
| bool isPath = Type::kPath == type; |
| SkASSERT(!path || isPath); |
| if (wasPath && !isPath) { |
| fPathData.fPath.~SkPath(); |
| } else if (!wasPath && isPath) { |
| if (path) { |
| new (&fPathData.fPath) SkPath(*path); |
| } else { |
| new (&fPathData.fPath) SkPath(); |
| } |
| } else if (isPath && path) { |
| fPathData.fPath = *path; |
| } |
| // Whether or not we use the path's gen ID is decided in attemptToSimplifyPath. |
| fPathData.fGenID = 0; |
| } |
| |
| SkPath& path() { |
| SkASSERT(Type::kPath == fType); |
| return fPathData.fPath; |
| } |
| |
| const SkPath& path() const { |
| SkASSERT(Type::kPath == fType); |
| return fPathData.fPath; |
| } |
| |
| /** 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 attemptToSimplifyPath(); |
| void attemptToSimplifyRRect(); |
| |
| // Defaults to use when there is no distinction between even/odd and winding fills. |
| static constexpr SkPath::FillType kDefaultPathFillType = SkPath::kEvenOdd_FillType; |
| static constexpr SkPath::FillType kDefaultPathInverseFillType = |
| SkPath::kInverseEvenOdd_FillType; |
| |
| 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; |
| union { |
| struct { |
| SkRRect fRRect; |
| SkPath::Direction fDir; |
| unsigned fStart; |
| bool fInverted; |
| } fRRectData; |
| struct { |
| SkPath fPath; |
| // Gen ID of the original path (fPath may be modified) |
| int32_t fGenID; |
| } fPathData; |
| }; |
| GrStyle fStyle; |
| SkAutoSTArray<8, uint32_t> fInheritedKey; |
| }; |
| #endif |