1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/gfx/skia/trunk/include/core/SkRRect.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,306 @@
1.4 +/*
1.5 + * Copyright 2012 Google Inc.
1.6 + *
1.7 + * Use of this source code is governed by a BSD-style license that can be
1.8 + * found in the LICENSE file.
1.9 + */
1.10 +
1.11 +#ifndef SkRRect_DEFINED
1.12 +#define SkRRect_DEFINED
1.13 +
1.14 +#include "SkRect.h"
1.15 +#include "SkPoint.h"
1.16 +
1.17 +class SkPath;
1.18 +class SkMatrix;
1.19 +
1.20 +// Path forward:
1.21 +// core work
1.22 +// add validate method (all radii positive, all radii sums < rect size, etc.)
1.23 +// add contains(SkRect&) - for clip stack
1.24 +// add contains(SkRRect&) - for clip stack
1.25 +// add heart rect computation (max rect inside RR)
1.26 +// add 9patch rect computation
1.27 +// add growToInclude(SkPath&)
1.28 +// analysis
1.29 +// use growToInclude to fit skp round rects & generate stats (RRs vs. real paths)
1.30 +// check on # of rectorus's the RRs could handle
1.31 +// rendering work
1.32 +// update SkPath.addRRect() to only use quads
1.33 +// add GM and bench
1.34 +// further out
1.35 +// detect and triangulate RRectorii rather than falling back to SW in Ganesh
1.36 +//
1.37 +
1.38 +/** \class SkRRect
1.39 +
1.40 + The SkRRect class represents a rounded rect with a potentially different
1.41 + radii for each corner. It does not have a constructor so must be
1.42 + initialized with one of the initialization functions (e.g., setEmpty,
1.43 + setRectRadii, etc.)
1.44 +
1.45 + This class is intended to roughly match CSS' border-*-*-radius capabilities.
1.46 + This means:
1.47 + If either of a corner's radii are 0 the corner will be square.
1.48 + Negative radii are not allowed (they are clamped to zero).
1.49 + If the corner curves overlap they will be proportionally reduced to fit.
1.50 +*/
1.51 +class SK_API SkRRect {
1.52 +public:
1.53 + /**
1.54 + * Enum to capture the various possible subtypes of RR. Accessed
1.55 + * by type(). The subtypes become progressively less restrictive.
1.56 + */
1.57 + enum Type {
1.58 + // !< Internal indicator that the sub type must be computed.
1.59 + kUnknown_Type = -1,
1.60 +
1.61 + // !< The RR is empty
1.62 + kEmpty_Type,
1.63 +
1.64 + //!< The RR is actually a (non-empty) rect (i.e., at least one radius
1.65 + //!< at each corner is zero)
1.66 + kRect_Type,
1.67 +
1.68 + //!< The RR is actually a (non-empty) oval (i.e., all x radii are equal
1.69 + //!< and >= width/2 and all the y radii are equal and >= height/2
1.70 + kOval_Type,
1.71 +
1.72 + //!< The RR is non-empty and all the x radii are equal & all y radii
1.73 + //!< are equal but it is not an oval (i.e., there are lines between
1.74 + //!< the curves) nor a rect (i.e., both radii are non-zero)
1.75 + kSimple_Type,
1.76 +
1.77 + //!< A fully general (non-empty) RR. Some of the x and/or y radii are
1.78 + //!< different from the others and there must be one corner where
1.79 + //!< both radii are non-zero.
1.80 + kComplex_Type,
1.81 + };
1.82 +
1.83 + /**
1.84 + * Returns the RR's sub type.
1.85 + */
1.86 + Type getType() const {
1.87 + SkDEBUGCODE(this->validate();)
1.88 +
1.89 + if (kUnknown_Type == fType) {
1.90 + this->computeType();
1.91 + }
1.92 + SkASSERT(kUnknown_Type != fType);
1.93 + return fType;
1.94 + }
1.95 +
1.96 + Type type() const { return this->getType(); }
1.97 +
1.98 + inline bool isEmpty() const { return kEmpty_Type == this->getType(); }
1.99 + inline bool isRect() const { return kRect_Type == this->getType(); }
1.100 + inline bool isOval() const { return kOval_Type == this->getType(); }
1.101 + inline bool isSimple() const { return kSimple_Type == this->getType(); }
1.102 + inline bool isSimpleCircular() const {
1.103 + return this->isSimple() && fRadii[0].fX == fRadii[0].fY;
1.104 + }
1.105 + inline bool isComplex() const { return kComplex_Type == this->getType(); }
1.106 +
1.107 + bool allCornersCircular() const;
1.108 +
1.109 + /**
1.110 + * Are both x-radii the same on the two left corners, and similar for the top, right, and
1.111 + * bottom. When this is the case the four ellipse centers form a rectangle.
1.112 + */
1.113 + bool isNinePatch() const {
1.114 + return fRadii[kUpperLeft_Corner].fX == fRadii[kLowerLeft_Corner].fX &&
1.115 + fRadii[kUpperRight_Corner].fX == fRadii[kLowerRight_Corner].fX &&
1.116 + fRadii[kUpperLeft_Corner].fY == fRadii[kUpperRight_Corner].fY &&
1.117 + fRadii[kLowerLeft_Corner].fY == fRadii[kLowerRight_Corner].fY;
1.118 + }
1.119 +
1.120 + SkScalar width() const { return fRect.width(); }
1.121 + SkScalar height() const { return fRect.height(); }
1.122 +
1.123 + /**
1.124 + * Set this RR to the empty rectangle (0,0,0,0) with 0 x & y radii.
1.125 + */
1.126 + void setEmpty() {
1.127 + fRect.setEmpty();
1.128 + memset(fRadii, 0, sizeof(fRadii));
1.129 + fType = kEmpty_Type;
1.130 +
1.131 + SkDEBUGCODE(this->validate();)
1.132 + }
1.133 +
1.134 + /**
1.135 + * Set this RR to match the supplied rect. All radii will be 0.
1.136 + */
1.137 + void setRect(const SkRect& rect) {
1.138 + if (rect.isEmpty()) {
1.139 + this->setEmpty();
1.140 + return;
1.141 + }
1.142 +
1.143 + fRect = rect;
1.144 + memset(fRadii, 0, sizeof(fRadii));
1.145 + fType = kRect_Type;
1.146 +
1.147 + SkDEBUGCODE(this->validate();)
1.148 + }
1.149 +
1.150 + /**
1.151 + * Set this RR to match the supplied oval. All x radii will equal half the
1.152 + * width and all y radii will equal half the height.
1.153 + */
1.154 + void setOval(const SkRect& oval) {
1.155 + if (oval.isEmpty()) {
1.156 + this->setEmpty();
1.157 + return;
1.158 + }
1.159 +
1.160 + SkScalar xRad = SkScalarHalf(oval.width());
1.161 + SkScalar yRad = SkScalarHalf(oval.height());
1.162 +
1.163 + fRect = oval;
1.164 + for (int i = 0; i < 4; ++i) {
1.165 + fRadii[i].set(xRad, yRad);
1.166 + }
1.167 + fType = kOval_Type;
1.168 +
1.169 + SkDEBUGCODE(this->validate();)
1.170 + }
1.171 +
1.172 + /**
1.173 + * Initialize the RR with the same radii for all four corners.
1.174 + */
1.175 + void setRectXY(const SkRect& rect, SkScalar xRad, SkScalar yRad);
1.176 +
1.177 + /**
1.178 + * Initialize the RR with potentially different radii for all four corners.
1.179 + */
1.180 + void setRectRadii(const SkRect& rect, const SkVector radii[4]);
1.181 +
1.182 + // The radii are stored in UL, UR, LR, LL order.
1.183 + enum Corner {
1.184 + kUpperLeft_Corner,
1.185 + kUpperRight_Corner,
1.186 + kLowerRight_Corner,
1.187 + kLowerLeft_Corner
1.188 + };
1.189 +
1.190 + const SkRect& rect() const { return fRect; }
1.191 + const SkVector& radii(Corner corner) const { return fRadii[corner]; }
1.192 + const SkRect& getBounds() const { return fRect; }
1.193 +
1.194 + /**
1.195 + * When a rrect is simple, all of its radii are equal. This returns one
1.196 + * of those radii. This call requires the rrect to be non-complex.
1.197 + */
1.198 + const SkVector& getSimpleRadii() const {
1.199 + SkASSERT(!this->isComplex());
1.200 + return fRadii[0];
1.201 + }
1.202 +
1.203 + friend bool operator==(const SkRRect& a, const SkRRect& b) {
1.204 + return a.fRect == b.fRect &&
1.205 + SkScalarsEqual(a.fRadii[0].asScalars(),
1.206 + b.fRadii[0].asScalars(), 8);
1.207 + }
1.208 +
1.209 + friend bool operator!=(const SkRRect& a, const SkRRect& b) {
1.210 + return a.fRect != b.fRect ||
1.211 + !SkScalarsEqual(a.fRadii[0].asScalars(),
1.212 + b.fRadii[0].asScalars(), 8);
1.213 + }
1.214 +
1.215 + /**
1.216 + * Call inset on the bounds, and adjust the radii to reflect what happens
1.217 + * in stroking: If the corner is sharp (no curvature), leave it alone,
1.218 + * otherwise we grow/shrink the radii by the amount of the inset. If a
1.219 + * given radius becomes negative, it is pinned to 0.
1.220 + *
1.221 + * It is valid for dst == this.
1.222 + */
1.223 + void inset(SkScalar dx, SkScalar dy, SkRRect* dst) const;
1.224 +
1.225 + void inset(SkScalar dx, SkScalar dy) {
1.226 + this->inset(dx, dy, this);
1.227 + }
1.228 +
1.229 + /**
1.230 + * Call outset on the bounds, and adjust the radii to reflect what happens
1.231 + * in stroking: If the corner is sharp (no curvature), leave it alone,
1.232 + * otherwise we grow/shrink the radii by the amount of the inset. If a
1.233 + * given radius becomes negative, it is pinned to 0.
1.234 + *
1.235 + * It is valid for dst == this.
1.236 + */
1.237 + void outset(SkScalar dx, SkScalar dy, SkRRect* dst) const {
1.238 + this->inset(-dx, -dy, dst);
1.239 + }
1.240 + void outset(SkScalar dx, SkScalar dy) {
1.241 + this->inset(-dx, -dy, this);
1.242 + }
1.243 +
1.244 + /**
1.245 + * Translate the rrect by (dx, dy).
1.246 + */
1.247 + void offset(SkScalar dx, SkScalar dy) {
1.248 + fRect.offset(dx, dy);
1.249 + }
1.250 +
1.251 + /**
1.252 + * Returns true if 'rect' is wholy inside the RR, and both
1.253 + * are not empty.
1.254 + */
1.255 + bool contains(const SkRect& rect) const;
1.256 +
1.257 + SkDEBUGCODE(void validate() const;)
1.258 +
1.259 + enum {
1.260 + kSizeInMemory = 12 * sizeof(SkScalar)
1.261 + };
1.262 +
1.263 + /**
1.264 + * Write the rrect into the specified buffer. This is guaranteed to always
1.265 + * write kSizeInMemory bytes, and that value is guaranteed to always be
1.266 + * a multiple of 4. Return kSizeInMemory.
1.267 + */
1.268 + size_t writeToMemory(void* buffer) const;
1.269 +
1.270 + /**
1.271 + * Reads the rrect from the specified buffer
1.272 + *
1.273 + * If the specified buffer is large enough, this will read kSizeInMemory bytes,
1.274 + * and that value is guaranteed to always be a multiple of 4.
1.275 + *
1.276 + * @param buffer Memory to read from
1.277 + * @param length Amount of memory available in the buffer
1.278 + * @return number of bytes read (must be a multiple of 4) or
1.279 + * 0 if there was not enough memory available
1.280 + */
1.281 + size_t readFromMemory(const void* buffer, size_t length);
1.282 +
1.283 + /**
1.284 + * Transform by the specified matrix, and put the result in dst.
1.285 + *
1.286 + * @param matrix SkMatrix specifying the transform. Must only contain
1.287 + * scale and/or translate, or this call will fail.
1.288 + * @param dst SkRRect to store the result. It is an error to use this,
1.289 + * which would make this function no longer const.
1.290 + * @return true on success, false on failure. If false, dst is unmodified.
1.291 + */
1.292 + bool transform(const SkMatrix& matrix, SkRRect* dst) const;
1.293 +
1.294 +private:
1.295 + SkRect fRect;
1.296 + // Radii order is UL, UR, LR, LL. Use Corner enum to index into fRadii[]
1.297 + SkVector fRadii[4];
1.298 + mutable Type fType;
1.299 + // TODO: add padding so we can use memcpy for flattening and not copy
1.300 + // uninitialized data
1.301 +
1.302 + void computeType() const;
1.303 + bool checkCornerContainment(SkScalar x, SkScalar y) const;
1.304 +
1.305 + // to access fRadii directly
1.306 + friend class SkPath;
1.307 +};
1.308 +
1.309 +#endif
