Пример #1
0
SkDashPathEffect::SkDashPathEffect(const SkScalar intervals[], int count,
                                   SkScalar phase, bool scaleToFit)
        : fScaleToFit(scaleToFit) {
    SkASSERT(intervals);
    SkASSERT(count > 1 && SkAlign2(count) == count);

    fIntervals = (SkScalar*)sk_malloc_throw(sizeof(SkScalar) * count);
    fCount = count;

    SkScalar len = 0;
    for (int i = 0; i < count; i++) {
        SkASSERT(intervals[i] >= 0);
        fIntervals[i] = intervals[i];
        len += intervals[i];
    }
    fIntervalLength = len;

    // watch out for values that might make us go out of bounds
    if ((len > 0) && SkScalarIsFinite(phase) && SkScalarIsFinite(len)) {

        // Adjust phase to be between 0 and len, "flipping" phase if negative.
        // e.g., if len is 100, then phase of -20 (or -120) is equivalent to 80
        if (phase < 0) {
            phase = -phase;
            if (phase > len) {
                phase = SkScalarMod(phase, len);
            }
            phase = len - phase;

            // Due to finite precision, it's possible that phase == len,
            // even after the subtract (if len >>> phase), so fix that here.
            // This fixes http://crbug.com/124652 .
            SkASSERT(phase <= len);
            if (phase == len) {
                phase = 0;
            }
        } else if (phase >= len) {
            phase = SkScalarMod(phase, len);
        }
        SkASSERT(phase >= 0 && phase < len);

        fInitialDashLength = FindFirstInterval(intervals, phase,
                                               &fInitialDashIndex, count);

        SkASSERT(fInitialDashLength >= 0);
        SkASSERT(fInitialDashIndex >= 0 && fInitialDashIndex < fCount);
    } else {
        fInitialDashLength = -1;    // signal bad dash intervals
    }
}
Пример #2
0
SkDashPathEffect::SkDashPathEffect(const SkScalar intervals[], int count,
                                   SkScalar phase) {
    SkASSERT(intervals);
    SkASSERT(count > 1 && SkAlign2(count) == count);

    fIntervals = (SkScalar*)sk_malloc_throw(sizeof(SkScalar) * count);
    fCount = count;
    for (int i = 0; i < count; i++) {
        SkASSERT(intervals[i] >= 0);
        fIntervals[i] = intervals[i];
    }

    this->setInternalMembers(phase);
}
Пример #3
0
SkDashPathEffect::SkDashPathEffect(const SkScalar intervals[], int count, SkScalar phase)
        : fPhase(0)
        , fInitialDashLength(-1)
        , fInitialDashIndex(0)
        , fIntervalLength(0) {
    SkASSERT(intervals);
    SkASSERT(count > 1 && SkAlign2(count) == count);

    fIntervals = (SkScalar*)sk_malloc_throw(sizeof(SkScalar) * count);
    fCount = count;
    for (int i = 0; i < count; i++) {
        fIntervals[i] = intervals[i];
    }

    // set the internal data members
    SkDashPath::CalcDashParameters(phase, fIntervals, fCount,
            &fInitialDashLength, &fInitialDashIndex, &fIntervalLength, &fPhase);
}
Пример #4
0
SkDashPathEffect::SkDashPathEffect(const SkScalar intervals[], int count, SkScalar phase, bool scaleToFit)
    : fScaleToFit(scaleToFit)
{
    SkASSERT(intervals);
    SkASSERT(count > 1 && SkAlign2(count) == count);

    fIntervals = (SkScalar*)sk_malloc_throw(sizeof(SkScalar) * count);
    fCount = count;

    SkScalar len = 0;
    for (int i = 0; i < count; i++)
    {
        SkASSERT(intervals[i] >= 0);
        fIntervals[i] = intervals[i];
        len += intervals[i];
    }
    fIntervalLength = len;

    if (len > 0)    // we don't handle 0 length dash arrays
    {
        if (phase < 0)
        {
            phase = -phase;
            if (phase > len)
                phase = SkScalarMod(phase, len);
            phase = len - phase;
        }
        else if (phase >= len)
            phase = SkScalarMod(phase, len);

        SkASSERT(phase >= 0 && phase < len);
        fInitialDashLength = FindFirstInterval(intervals, phase, &fInitialDashIndex);

        SkASSERT(fInitialDashLength >= 0);
        SkASSERT(fInitialDashIndex >= 0 && fInitialDashIndex < fCount);
    }
    else
        fInitialDashLength = -1;    // signal bad dash intervals
}
Пример #5
0
/*
 * Performs the bitmap decoding for RLE input format
 * RLE decoding is performed all at once, rather than a one row at a time
 */
SkCodec::Result SkBmpRLECodec::decode(const SkImageInfo& dstInfo,
                                      void* dst, size_t dstRowBytes,
                                      const Options& opts) {
    // Set RLE flags
    static const uint8_t RLE_ESCAPE = 0;
    static const uint8_t RLE_EOL = 0;
    static const uint8_t RLE_EOF = 1;
    static const uint8_t RLE_DELTA = 2;

    // Set constant values
    const int width = dstInfo.width();
    const int height = dstInfo.height();

    // Destination parameters
    int x = 0;
    int y = 0;

    // Set the background as transparent.  Then, if the RLE code skips pixels,
    // the skipped pixels will be transparent.
    // Because of the need for transparent pixels, kN32 is the only color
    // type that makes sense for the destination format.
    SkASSERT(kN32_SkColorType == dstInfo.colorType());
    if (kNo_ZeroInitialized == opts.fZeroInitialized) {
        SkSwizzler::Fill(dst, dstInfo, dstRowBytes, height, SK_ColorTRANSPARENT, NULL);
    }

    while (true) {
        // If we have reached a row that is beyond the requested height, we have
        // succeeded.
        if (y >= height) {
            // It would be better to check for the EOF marker before returning
            // success, but we may be performing a scanline decode, which
            // may require us to stop before decoding the full height.
            return kSuccess;
        }

        // Every entry takes at least two bytes
        if ((int) fRLEBytes - fCurrRLEByte < 2) {
            SkCodecPrintf("Warning: might be incomplete RLE input.\n");
            if (this->checkForMoreData() < 2) {
                return kIncompleteInput;
            }
        }

        // Read the next two bytes.  These bytes have different meanings
        // depending on their values.  In the first interpretation, the first
        // byte is an escape flag and the second byte indicates what special
        // task to perform.
        const uint8_t flag = fStreamBuffer.get()[fCurrRLEByte++];
        const uint8_t task = fStreamBuffer.get()[fCurrRLEByte++];

        // Perform decoding
        if (RLE_ESCAPE == flag) {
            switch (task) {
                case RLE_EOL:
                    x = 0;
                    y++;
                    break;
                case RLE_EOF:
                    return kSuccess;
                case RLE_DELTA: {
                    // Two bytes are needed to specify delta
                    if ((int) fRLEBytes - fCurrRLEByte < 2) {
                        SkCodecPrintf("Warning: might be incomplete RLE input.\n");
                        if (this->checkForMoreData() < 2) {
                            return kIncompleteInput;
                        }
                    }
                    // Modify x and y
                    const uint8_t dx = fStreamBuffer.get()[fCurrRLEByte++];
                    const uint8_t dy = fStreamBuffer.get()[fCurrRLEByte++];
                    x += dx;
                    y += dy;
                    if (x > width || y > height) {
                        SkCodecPrintf("Warning: invalid RLE input.\n");
                        return kInvalidInput;
                    }
                    break;
                }
                default: {
                    // If task does not match any of the above signals, it
                    // indicates that we have a sequence of non-RLE pixels.
                    // Furthermore, the value of task is equal to the number
                    // of pixels to interpret.
                    uint8_t numPixels = task;
                    const size_t rowBytes = compute_row_bytes(numPixels,
                            this->bitsPerPixel());
                    // Abort if setting numPixels moves us off the edge of the
                    // image.
                    if (x + numPixels > width) {
                        SkCodecPrintf("Warning: invalid RLE input.\n");
                        return kInvalidInput;
                    }
                    // Also abort if there are not enough bytes
                    // remaining in the stream to set numPixels.
                    if ((int) fRLEBytes - fCurrRLEByte < SkAlign2(rowBytes)) {
                        SkCodecPrintf("Warning: might be incomplete RLE input.\n");
                        if (this->checkForMoreData() < SkAlign2(rowBytes)) {
                            return kIncompleteInput;
                        }
                    }
                    // Set numPixels number of pixels
                    while (numPixels > 0) {
                        switch(this->bitsPerPixel()) {
                            case 4: {
                                SkASSERT(fCurrRLEByte < fRLEBytes);
                                uint8_t val = fStreamBuffer.get()[fCurrRLEByte++];
                                setPixel(dst, dstRowBytes, dstInfo, x++,
                                        y, val >> 4);
                                numPixels--;
                                if (numPixels != 0) {
                                    setPixel(dst, dstRowBytes, dstInfo,
                                            x++, y, val & 0xF);
                                    numPixels--;
                                }
                                break;
                            }
                            case 8:
                                SkASSERT(fCurrRLEByte < fRLEBytes);
                                setPixel(dst, dstRowBytes, dstInfo, x++,
                                        y, fStreamBuffer.get()[fCurrRLEByte++]);
                                numPixels--;
                                break;
                            case 24: {
                                SkASSERT(fCurrRLEByte + 2 < fRLEBytes);
                                uint8_t blue = fStreamBuffer.get()[fCurrRLEByte++];
                                uint8_t green = fStreamBuffer.get()[fCurrRLEByte++];
                                uint8_t red = fStreamBuffer.get()[fCurrRLEByte++];
                                setRGBPixel(dst, dstRowBytes, dstInfo,
                                            x++, y, red, green, blue);
                                numPixels--;
                            }
                            default:
                                SkASSERT(false);
                                return kInvalidInput;
                        }
                    }
                    // Skip a byte if necessary to maintain alignment
                    if (!SkIsAlign2(rowBytes)) {
                        fCurrRLEByte++;
                    }
                    break;
                }
            }
        } else {
            // If the first byte read is not a flag, it indicates the number of
            // pixels to set in RLE mode.
            const uint8_t numPixels = flag;
            const int endX = SkTMin<int>(x + numPixels, width);

            if (24 == this->bitsPerPixel()) {
                // In RLE24, the second byte read is part of the pixel color.
                // There are two more required bytes to finish encoding the
                // color.
                if ((int) fRLEBytes - fCurrRLEByte < 2) {
                    SkCodecPrintf("Warning: might be incomplete RLE input.\n");
                    if (this->checkForMoreData() < 2) {
                        return kIncompleteInput;
                    }
                }

                // Fill the pixels up to endX with the specified color
                uint8_t blue = task;
                uint8_t green = fStreamBuffer.get()[fCurrRLEByte++];
                uint8_t red = fStreamBuffer.get()[fCurrRLEByte++];
                while (x < endX) {
                    setRGBPixel(dst, dstRowBytes, dstInfo, x++, y, red,
                            green, blue);
                }
            } else {
                // In RLE8 or RLE4, the second byte read gives the index in the
                // color table to look up the pixel color.
                // RLE8 has one color index that gets repeated
                // RLE4 has two color indexes in the upper and lower 4 bits of
                // the bytes, which are alternated
                uint8_t indices[2] = { task, task };
                if (4 == this->bitsPerPixel()) {
                    indices[0] >>= 4;
                    indices[1] &= 0xf;
                }

                // Set the indicated number of pixels
                for (int which = 0; x < endX; x++) {
                    setPixel(dst, dstRowBytes, dstInfo, x, y,
                            indices[which]);
                    which = !which;
                }
            }
        }