The Tor Browser: gfx/skia/trunk/src/utils/SkInterpolator.cpp@129ffea94266 (annotated)

gfx/skia/trunk/src/utils/SkInterpolator.cpp@129ffea94266 (annotated)

gfx/skia/trunk/src/utils/SkInterpolator.cpp

Sat, 03 Jan 2015 20:18:00 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Sat, 03 Jan 2015 20:18:00 +0100
branch: TOR_BUG_3246
changeset 7: 129ffea94266
permissions: -rw-r--r--

Conditionally enable double key logic according to:
private browsing mode or privacy.thirdparty.isolate preference and
implement in GetCookieStringCommon and FindCookie where it counts...
With some reservations of how to convince FindCookie users to test
condition and pass a nullptr when disabling double key logic.

 /*
  * Copyright 2008 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 #include "SkInterpolator.h"
 #include "SkMath.h"
 #include "SkTSearch.h"
 SkInterpolatorBase::SkInterpolatorBase() {
     fStorage    = NULL;
     fTimes      = NULL;
     SkDEBUGCODE(fTimesArray = NULL;)
 }
 SkInterpolatorBase::~SkInterpolatorBase() {
     if (fStorage) {
         sk_free(fStorage);
     }
 }
 void SkInterpolatorBase::reset(int elemCount, int frameCount) {
     fFlags = 0;
     fElemCount = SkToU8(elemCount);
     fFrameCount = SkToS16(frameCount);
     fRepeat = SK_Scalar1;
     if (fStorage) {
         sk_free(fStorage);
         fStorage = NULL;
         fTimes = NULL;
         SkDEBUGCODE(fTimesArray = NULL);
     }
 }
 /*  Each value[] run is formated as:
         <time (in msec)>
         <blend>
         <data[fElemCount]>
     Totaling fElemCount+2 entries per keyframe
 */
 bool SkInterpolatorBase::getDuration(SkMSec* startTime, SkMSec* endTime) const {
     if (fFrameCount == 0) {
         return false;
     }
     if (startTime) {
         *startTime = fTimes[0].fTime;
     }
     if (endTime) {
         *endTime = fTimes[fFrameCount - 1].fTime;
     }
     return true;
 }
 SkScalar SkInterpolatorBase::ComputeRelativeT(SkMSec time, SkMSec prevTime,
                                   SkMSec nextTime, const SkScalar blend[4]) {
     SkASSERT(time > prevTime && time < nextTime);
     SkScalar t = SkScalarDiv((SkScalar)(time - prevTime),
                              (SkScalar)(nextTime - prevTime));
     return blend ?
             SkUnitCubicInterp(t, blend[0], blend[1], blend[2], blend[3]) : t;
 }
 SkInterpolatorBase::Result SkInterpolatorBase::timeToT(SkMSec time, SkScalar* T,
                                         int* indexPtr, SkBool* exactPtr) const {
     SkASSERT(fFrameCount > 0);
     Result  result = kNormal_Result;
     if (fRepeat != SK_Scalar1) {
         SkMSec startTime = 0, endTime = 0;  // initialize to avoid warning
         this->getDuration(&startTime, &endTime);
         SkMSec totalTime = endTime - startTime;
         SkMSec offsetTime = time - startTime;
         endTime = SkScalarFloorToInt(fRepeat * totalTime);
         if (offsetTime >= endTime) {
             SkScalar fraction = SkScalarFraction(fRepeat);
             offsetTime = fraction == 0 && fRepeat > 0 ? totalTime :
                 (SkMSec) SkScalarFloorToInt(fraction * totalTime);
             result = kFreezeEnd_Result;
         } else {
             int mirror = fFlags & kMirror;
             offsetTime = offsetTime % (totalTime << mirror);
             if (offsetTime > totalTime) { // can only be true if fMirror is true
                 offsetTime = (totalTime << 1) - offsetTime;
             }
         }
         time = offsetTime + startTime;
     }
     int index = SkTSearch<SkMSec>(&fTimes[0].fTime, fFrameCount, time,
                                   sizeof(SkTimeCode));
     bool    exact = true;
     if (index < 0) {
         index = ~index;
         if (index == 0) {
             result = kFreezeStart_Result;
         } else if (index == fFrameCount) {
             if (fFlags & kReset) {
                 index = 0;
             } else {
                 index -= 1;
             }
             result = kFreezeEnd_Result;
         } else {
             exact = false;
         }
     }
     SkASSERT(index < fFrameCount);
     const SkTimeCode* nextTime = &fTimes[index];
     SkMSec   nextT = nextTime[0].fTime;
     if (exact) {
         *T = 0;
     } else {
         SkMSec prevT = nextTime[-1].fTime;
         *T = ComputeRelativeT(time, prevT, nextT, nextTime[-1].fBlend);
     }
     *indexPtr = index;
     *exactPtr = exact;
     return result;
 }
 SkInterpolator::SkInterpolator() {
     INHERITED::reset(0, 0);
     fValues = NULL;
     SkDEBUGCODE(fScalarsArray = NULL;)
 }
 SkInterpolator::SkInterpolator(int elemCount, int frameCount) {
     SkASSERT(elemCount > 0);
     this->reset(elemCount, frameCount);
 }
 void SkInterpolator::reset(int elemCount, int frameCount) {
     INHERITED::reset(elemCount, frameCount);
     fStorage = sk_malloc_throw((sizeof(SkScalar) * elemCount +
                                 sizeof(SkTimeCode)) * frameCount);
     fTimes = (SkTimeCode*) fStorage;
     fValues = (SkScalar*) ((char*) fStorage + sizeof(SkTimeCode) * frameCount);
 #ifdef SK_DEBUG
     fTimesArray = (SkTimeCode(*)[10]) fTimes;
     fScalarsArray = (SkScalar(*)[10]) fValues;
 #endif
 }
 #define SK_Fixed1Third      (SK_Fixed1/3)
 #define SK_Fixed2Third      (SK_Fixed1*2/3)
 static const SkScalar gIdentityBlend[4] = {
 .33333333f, 0.33333333f, 0.66666667f, 0.66666667f
 };
 bool SkInterpolator::setKeyFrame(int index, SkMSec time,
                             const SkScalar values[], const SkScalar blend[4]) {
     SkASSERT(values != NULL);
     if (blend == NULL) {
         blend = gIdentityBlend;
     }
     bool success = ~index == SkTSearch<SkMSec>(&fTimes->fTime, index, time,
                                                sizeof(SkTimeCode));
     SkASSERT(success);
     if (success) {
         SkTimeCode* timeCode = &fTimes[index];
         timeCode->fTime = time;
         memcpy(timeCode->fBlend, blend, sizeof(timeCode->fBlend));
         SkScalar* dst = &fValues[fElemCount * index];
         memcpy(dst, values, fElemCount * sizeof(SkScalar));
     }
     return success;
 }
 SkInterpolator::Result SkInterpolator::timeToValues(SkMSec time,
                                                     SkScalar values[]) const {
     SkScalar T;
     int index;
     SkBool exact;
     Result result = timeToT(time, &T, &index, &exact);
     if (values) {
         const SkScalar* nextSrc = &fValues[index * fElemCount];
         if (exact) {
             memcpy(values, nextSrc, fElemCount * sizeof(SkScalar));
         } else {
             SkASSERT(index > 0);
             const SkScalar* prevSrc = nextSrc - fElemCount;
             for (int i = fElemCount - 1; i >= 0; --i) {
                 values[i] = SkScalarInterp(prevSrc[i], nextSrc[i], T);
             }
         }
     }
     return result;
 }
 ///////////////////////////////////////////////////////////////////////////////
 typedef int Dot14;
 #define Dot14_ONE       (1 << 14)
 #define Dot14_HALF      (1 << 13)
 #define Dot14ToFloat(x) ((x) / 16384.f)
 static inline Dot14 Dot14Mul(Dot14 a, Dot14 b) {
     return (a * b + Dot14_HALF) >> 14;
 }
 static inline Dot14 eval_cubic(Dot14 t, Dot14 A, Dot14 B, Dot14 C) {
     return Dot14Mul(Dot14Mul(Dot14Mul(C, t) + B, t) + A, t);
 }
 static inline Dot14 pin_and_convert(SkScalar x) {
     if (x <= 0) {
         return 0;
     }
     if (x >= SK_Scalar1) {
         return Dot14_ONE;
     }
     return SkScalarToFixed(x) >> 2;
 }
 SkScalar SkUnitCubicInterp(SkScalar value, SkScalar bx, SkScalar by,
                            SkScalar cx, SkScalar cy) {
     // pin to the unit-square, and convert to 2.14
     Dot14 x = pin_and_convert(value);
     if (x == 0) return 0;
     if (x == Dot14_ONE) return SK_Scalar1;
     Dot14 b = pin_and_convert(bx);
     Dot14 c = pin_and_convert(cx);
     // Now compute our coefficients from the control points
     //  t   -> 3b
     //  t^2 -> 3c - 6b
     //  t^3 -> 3b - 3c + 1
     Dot14 A = 3*b;
     Dot14 B = 3*(c - 2*b);
     Dot14 C = 3*(b - c) + Dot14_ONE;
     // Now search for a t value given x
     Dot14   t = Dot14_HALF;
     Dot14   dt = Dot14_HALF;
     for (int i = 0; i < 13; i++) {
         dt >>= 1;
         Dot14 guess = eval_cubic(t, A, B, C);
         if (x < guess) {
             t -= dt;
         } else {
             t += dt;
         }
     }
     // Now we have t, so compute the coeff for Y and evaluate
     b = pin_and_convert(by);
     c = pin_and_convert(cy);
     A = 3*b;
     B = 3*(c - 2*b);
     C = 3*(b - c) + Dot14_ONE;
     return SkFixedToScalar(eval_cubic(t, A, B, C) << 2);
 }
 ///////////////////////////////////////////////////////////////////////////////
 ///////////////////////////////////////////////////////////////////////////////
 #ifdef SK_DEBUG
 #ifdef SK_SUPPORT_UNITTEST
     static SkScalar* iset(SkScalar array[3], int a, int b, int c) {
         array[0] = SkIntToScalar(a);
         array[1] = SkIntToScalar(b);
         array[2] = SkIntToScalar(c);
         return array;
     }
 #endif
 void SkInterpolator::UnitTest() {
 #ifdef SK_SUPPORT_UNITTEST
     SkInterpolator  inter(3, 2);
     SkScalar        v1[3], v2[3], v[3], vv[3];
     Result          result;
     inter.setKeyFrame(0, 100, iset(v1, 10, 20, 30), 0);
     inter.setKeyFrame(1, 200, iset(v2, 110, 220, 330));
     result = inter.timeToValues(0, v);
     SkASSERT(result == kFreezeStart_Result);
     SkASSERT(memcmp(v, v1, sizeof(v)) == 0);
     result = inter.timeToValues(99, v);
     SkASSERT(result == kFreezeStart_Result);
     SkASSERT(memcmp(v, v1, sizeof(v)) == 0);
     result = inter.timeToValues(100, v);
     SkASSERT(result == kNormal_Result);
     SkASSERT(memcmp(v, v1, sizeof(v)) == 0);
     result = inter.timeToValues(200, v);
     SkASSERT(result == kNormal_Result);
     SkASSERT(memcmp(v, v2, sizeof(v)) == 0);
     result = inter.timeToValues(201, v);
     SkASSERT(result == kFreezeEnd_Result);
     SkASSERT(memcmp(v, v2, sizeof(v)) == 0);
     result = inter.timeToValues(150, v);
     SkASSERT(result == kNormal_Result);
     SkASSERT(memcmp(v, iset(vv, 60, 120, 180), sizeof(v)) == 0);
     result = inter.timeToValues(125, v);
     SkASSERT(result == kNormal_Result);
     result = inter.timeToValues(175, v);
     SkASSERT(result == kNormal_Result);
 #endif
 }
 #endif

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gfx/skia/trunk/src/utils/SkInterpolator.cpp@129ffea94266 (annotated)

gfx/skia/trunk/src/utils/SkInterpolator.cpp