The Tor Browser: gfx/skia/trunk/src/core/SkConvolver.h@129ffea94266 (annotated)

gfx/skia/trunk/src/core/SkConvolver.h@129ffea94266 (annotated)

gfx/skia/trunk/src/core/SkConvolver.h

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 (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 #ifndef SK_CONVOLVER_H
 #define SK_CONVOLVER_H
 #include "SkSize.h"
 #include "SkTypes.h"
 #include "SkTArray.h"
 // avoid confusion with Mac OS X's math library (Carbon)
 #if defined(__APPLE__)
 #undef FloatToConvolutionFixed
 #undef ConvolutionFixedToFloat
 #endif
 // Represents a filter in one dimension. Each output pixel has one entry in this
 // object for the filter values contributing to it. You build up the filter
 // list by calling AddFilter for each output pixel (in order).
 //
 // We do 2-dimensional convolution by first convolving each row by one
 // SkConvolutionFilter1D, then convolving each column by another one.
 //
 // Entries are stored in ConvolutionFixed point, shifted left by kShiftBits.
 class SkConvolutionFilter1D {
 public:
     typedef short ConvolutionFixed;
     // The number of bits that ConvolutionFixed point values are shifted by.
     enum { kShiftBits = 14 };
     SK_API SkConvolutionFilter1D();
     SK_API ~SkConvolutionFilter1D();
     // Convert between floating point and our ConvolutionFixed point representation.
     static ConvolutionFixed FloatToFixed(float f) {
         return static_cast<ConvolutionFixed>(f * (1 << kShiftBits));
     }
     static unsigned char FixedToChar(ConvolutionFixed x) {
         return static_cast<unsigned char>(x >> kShiftBits);
     }
     static float FixedToFloat(ConvolutionFixed x) {
         // The cast relies on ConvolutionFixed being a short, implying that on
         // the platforms we care about all (16) bits will fit into
         // the mantissa of a (32-bit) float.
         SK_COMPILE_ASSERT(sizeof(ConvolutionFixed) == 2, ConvolutionFixed_type_should_fit_in_float_mantissa);
         float raw = static_cast<float>(x);
         return ldexpf(raw, -kShiftBits);
     }
     // Returns the maximum pixel span of a filter.
     int maxFilter() const { return fMaxFilter; }
     // Returns the number of filters in this filter. This is the dimension of the
     // output image.
     int numValues() const { return static_cast<int>(fFilters.count()); }
     // Appends the given list of scaling values for generating a given output
     // pixel. |filterOffset| is the distance from the edge of the image to where
     // the scaling factors start. The scaling factors apply to the source pixels
     // starting from this position, and going for the next |filterLength| pixels.
     //
     // You will probably want to make sure your input is normalized (that is,
     // all entries in |filterValuesg| sub to one) to prevent affecting the overall
     // brighness of the image.
     //
     // The filterLength must be > 0.
     //
     // This version will automatically convert your input to ConvolutionFixed point.
     SK_API void AddFilter(int filterOffset,
                           const float* filterValues,
                           int filterLength);
     // Same as the above version, but the input is already ConvolutionFixed point.
     void AddFilter(int filterOffset,
                    const ConvolutionFixed* filterValues,
                    int filterLength);
     // Retrieves a filter for the given |valueOffset|, a position in the output
     // image in the direction we're convolving. The offset and length of the
     // filter values are put into the corresponding out arguments (see AddFilter
     // above for what these mean), and a pointer to the first scaling factor is
     // returned. There will be |filterLength| values in this array.
     inline const ConvolutionFixed* FilterForValue(int valueOffset,
                                        int* filterOffset,
                                        int* filterLength) const {
         const FilterInstance& filter = fFilters[valueOffset];
         *filterOffset = filter.fOffset;
         *filterLength = filter.fTrimmedLength;
         if (filter.fTrimmedLength == 0) {
             return NULL;
         }
         return &fFilterValues[filter.fDataLocation];
     }
   // Retrieves the filter for the offset 0, presumed to be the one and only.
   // The offset and length of the filter values are put into the corresponding
   // out arguments (see AddFilter). Note that |filterLegth| and
   // |specifiedFilterLength| may be different if leading/trailing zeros of the
   // original floating point form were clipped.
   // There will be |filterLength| values in the return array.
   // Returns NULL if the filter is 0-length (for instance when all floating
   // point values passed to AddFilter were clipped to 0).
     SK_API const ConvolutionFixed* GetSingleFilter(int* specifiedFilterLength,
         int* filterOffset,
         int* filterLength) const;
     // Add another value to the fFilterValues array -- useful for
     // SIMD padding which happens outside of this class.
     void addFilterValue( ConvolutionFixed val ) {
         fFilterValues.push_back( val );
     }
 private:
     struct FilterInstance {
         // Offset within filterValues for this instance of the filter.
         int fDataLocation;
         // Distance from the left of the filter to the center. IN PIXELS
         int fOffset;
         // Number of values in this filter instance.
         int fTrimmedLength;
         // Filter length as specified. Note that this may be different from
         // 'trimmed_length' if leading/trailing zeros of the original floating
         // point form were clipped differently on each tail.
         int fLength;
     };
     // Stores the information for each filter added to this class.
     SkTArray<FilterInstance> fFilters;
     // We store all the filter values in this flat list, indexed by
     // |FilterInstance.data_location| to avoid the mallocs required for storing
     // each one separately.
     SkTArray<ConvolutionFixed> fFilterValues;
     // The maximum size of any filter we've added.
     int fMaxFilter;
 };
 typedef void (*SkConvolveVertically_pointer)(
     const SkConvolutionFilter1D::ConvolutionFixed* filterValues,
     int filterLength,
     unsigned char* const* sourceDataRows,
     int pixelWidth,
     unsigned char* outRow,
     bool hasAlpha);
 typedef void (*SkConvolve4RowsHorizontally_pointer)(
     const unsigned char* srcData[4],
     const SkConvolutionFilter1D& filter,
     unsigned char* outRow[4]);
 typedef void (*SkConvolveHorizontally_pointer)(
     const unsigned char* srcData,
     const SkConvolutionFilter1D& filter,
     unsigned char* outRow,
     bool hasAlpha);
 typedef void (*SkConvolveFilterPadding_pointer)(
     SkConvolutionFilter1D* filter);
 struct SkConvolutionProcs {
   // This is how many extra pixels may be read by the
   // conolve*horizontally functions.
     int fExtraHorizontalReads;
     SkConvolveVertically_pointer fConvolveVertically;
     SkConvolve4RowsHorizontally_pointer fConvolve4RowsHorizontally;
     SkConvolveHorizontally_pointer fConvolveHorizontally;
     SkConvolveFilterPadding_pointer fApplySIMDPadding;
 };
 // Does a two-dimensional convolution on the given source image.
 //
 // It is assumed the source pixel offsets referenced in the input filters
 // reference only valid pixels, so the source image size is not required. Each
 // row of the source image starts |sourceByteRowStride| after the previous
 // one (this allows you to have rows with some padding at the end).
 //
 // The result will be put into the given output buffer. The destination image
 // size will be xfilter.numValues() * yfilter.numValues() pixels. It will be
 // in rows of exactly xfilter.numValues() * 4 bytes.
 //
 // |sourceHasAlpha| is a hint that allows us to avoid doing computations on
 // the alpha channel if the image is opaque. If you don't know, set this to
 // true and it will work properly, but setting this to false will be a few
 // percent faster if you know the image is opaque.
 //
 // The layout in memory is assumed to be 4-bytes per pixel in B-G-R-A order
 // (this is ARGB when loaded into 32-bit words on a little-endian machine).
 SK_API void BGRAConvolve2D(const unsigned char* sourceData,
     int sourceByteRowStride,
     bool sourceHasAlpha,
     const SkConvolutionFilter1D& xfilter,
     const SkConvolutionFilter1D& yfilter,
     int outputByteRowStride,
     unsigned char* output,
     const SkConvolutionProcs&,
     bool useSimdIfPossible);
 #endif  // SK_CONVOLVER_H

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gfx/skia/trunk/src/core/SkConvolver.h@129ffea94266 (annotated)

gfx/skia/trunk/src/core/SkConvolver.h