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Diffstat (limited to 'src/gui/painting/qimageeffects.cpp')
| -rw-r--r-- | src/gui/painting/qimageeffects.cpp | 327 |
1 files changed, 327 insertions, 0 deletions
diff --git a/src/gui/painting/qimageeffects.cpp b/src/gui/painting/qimageeffects.cpp new file mode 100644 index 0000000000..7c2b947e08 --- /dev/null +++ b/src/gui/painting/qimageeffects.cpp @@ -0,0 +1,327 @@ +// Copyright (C) 2016 The Qt Company Ltd. +// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only + +#include "qmath.h" +#include "qdrawhelper_p.h" +#include "qmemrotate_p.h" +#include "qpainter.h" + +#include <memory> + +QT_BEGIN_NAMESPACE + +namespace { + +template <int shift> +inline int qt_static_shift(int value) +{ + if (shift == 0) + return value; + else if (shift > 0) + return value << (uint(shift) & 0x1f); + else + return value >> (uint(-shift) & 0x1f); +} + +template<int aprec, int zprec> +inline void qt_blurinner(uchar *bptr, int &zR, int &zG, int &zB, int &zA, int alpha) +{ + QRgb *pixel = (QRgb *)bptr; + +#define Z_MASK (0xff << zprec) + const int A_zprec = qt_static_shift<zprec - 24>(*pixel) & Z_MASK; + const int R_zprec = qt_static_shift<zprec - 16>(*pixel) & Z_MASK; + const int G_zprec = qt_static_shift<zprec - 8>(*pixel) & Z_MASK; + const int B_zprec = qt_static_shift<zprec>(*pixel) & Z_MASK; +#undef Z_MASK + + const int zR_zprec = zR >> aprec; + const int zG_zprec = zG >> aprec; + const int zB_zprec = zB >> aprec; + const int zA_zprec = zA >> aprec; + + zR += alpha * (R_zprec - zR_zprec); + zG += alpha * (G_zprec - zG_zprec); + zB += alpha * (B_zprec - zB_zprec); + zA += alpha * (A_zprec - zA_zprec); + +#define ZA_MASK (0xff << (zprec + aprec)) + *pixel = + qt_static_shift<24 - zprec - aprec>(zA & ZA_MASK) + | qt_static_shift<16 - zprec - aprec>(zR & ZA_MASK) + | qt_static_shift<8 - zprec - aprec>(zG & ZA_MASK) + | qt_static_shift<-zprec - aprec>(zB & ZA_MASK); +#undef ZA_MASK +} + +const int alphaIndex = (QSysInfo::ByteOrder == QSysInfo::BigEndian ? 0 : 3); + +template<int aprec, int zprec> +inline void qt_blurinner_alphaOnly(uchar *bptr, int &z, int alpha) +{ + const int A_zprec = int(*(bptr)) << zprec; + const int z_zprec = z >> aprec; + z += alpha * (A_zprec - z_zprec); + *(bptr) = z >> (zprec + aprec); +} + +template<int aprec, int zprec, bool alphaOnly> +inline void qt_blurrow(QImage & im, int line, int alpha) +{ + uchar *bptr = im.scanLine(line); + + int zR = 0, zG = 0, zB = 0, zA = 0; + + if (alphaOnly && im.format() != QImage::Format_Indexed8) + bptr += alphaIndex; + + const int stride = im.depth() >> 3; + const int im_width = im.width(); + for (int index = 0; index < im_width; ++index) { + if (alphaOnly) + qt_blurinner_alphaOnly<aprec, zprec>(bptr, zA, alpha); + else + qt_blurinner<aprec, zprec>(bptr, zR, zG, zB, zA, alpha); + bptr += stride; + } + + bptr -= stride; + + for (int index = im_width - 2; index >= 0; --index) { + bptr -= stride; + if (alphaOnly) + qt_blurinner_alphaOnly<aprec, zprec>(bptr, zA, alpha); + else + qt_blurinner<aprec, zprec>(bptr, zR, zG, zB, zA, alpha); + } +} + +/* +* expblur(QImage &img, int radius) +* +* Based on exponential blur algorithm by Jani Huhtanen +* +* In-place blur of image 'img' with kernel +* of approximate radius 'radius'. +* +* Blurs with two sided exponential impulse +* response. +* +* aprec = precision of alpha parameter +* in fixed-point format 0.aprec +* +* zprec = precision of state parameters +* zR,zG,zB and zA in fp format 8.zprec +*/ +template <int aprec, int zprec, bool alphaOnly> +void expblur(QImage &img, qreal radius, bool improvedQuality = false, int transposed = 0) +{ + // halve the radius if we're using two passes + if (improvedQuality) + radius *= qreal(0.5); + + Q_ASSERT(img.format() == QImage::Format_ARGB32_Premultiplied + || img.format() == QImage::Format_RGB32 + || img.format() == QImage::Format_Indexed8 + || img.format() == QImage::Format_Grayscale8); + + // choose the alpha such that pixels at radius distance from a fully + // saturated pixel will have an alpha component of no greater than + // the cutOffIntensity + const qreal cutOffIntensity = 2; + int alpha = radius <= qreal(1e-5) + ? ((1 << aprec)-1) + : qRound((1<<aprec)*(1 - qPow(cutOffIntensity * (1 / qreal(255)), 1 / radius))); + + int img_height = img.height(); + for (int row = 0; row < img_height; ++row) { + for (int i = 0; i <= int(improvedQuality); ++i) + qt_blurrow<aprec, zprec, alphaOnly>(img, row, alpha); + } + + QImage temp(img.height(), img.width(), img.format()); + temp.setDevicePixelRatio(img.devicePixelRatio()); + if (transposed >= 0) { + if (img.depth() == 8) { + qt_memrotate270(reinterpret_cast<const quint8*>(img.bits()), + img.width(), img.height(), img.bytesPerLine(), + reinterpret_cast<quint8*>(temp.bits()), + temp.bytesPerLine()); + } else { + qt_memrotate270(reinterpret_cast<const quint32*>(img.bits()), + img.width(), img.height(), img.bytesPerLine(), + reinterpret_cast<quint32*>(temp.bits()), + temp.bytesPerLine()); + } + } else { + if (img.depth() == 8) { + qt_memrotate90(reinterpret_cast<const quint8*>(img.bits()), + img.width(), img.height(), img.bytesPerLine(), + reinterpret_cast<quint8*>(temp.bits()), + temp.bytesPerLine()); + } else { + qt_memrotate90(reinterpret_cast<const quint32*>(img.bits()), + img.width(), img.height(), img.bytesPerLine(), + reinterpret_cast<quint32*>(temp.bits()), + temp.bytesPerLine()); + } + } + + img_height = temp.height(); + for (int row = 0; row < img_height; ++row) { + for (int i = 0; i <= int(improvedQuality); ++i) + qt_blurrow<aprec, zprec, alphaOnly>(temp, row, alpha); + } + + if (transposed == 0) { + if (img.depth() == 8) { + qt_memrotate90(reinterpret_cast<const quint8*>(temp.bits()), + temp.width(), temp.height(), temp.bytesPerLine(), + reinterpret_cast<quint8*>(img.bits()), + img.bytesPerLine()); + } else { + qt_memrotate90(reinterpret_cast<const quint32*>(temp.bits()), + temp.width(), temp.height(), temp.bytesPerLine(), + reinterpret_cast<quint32*>(img.bits()), + img.bytesPerLine()); + } + } else { + img = temp; + } +} + +} // namespace + +#define AVG(a,b) ( ((((a)^(b)) & 0xfefefefeUL) >> 1) + ((a)&(b)) ) +#define AVG16(a,b) ( ((((a)^(b)) & 0xf7deUL) >> 1) + ((a)&(b)) ) + +QImage qt_halfScaled(const QImage &source) +{ + if (source.width() < 2 || source.height() < 2) + return QImage(); + + QImage srcImage = source; + + if (source.format() == QImage::Format_Indexed8 || source.format() == QImage::Format_Grayscale8) { + // assumes grayscale + QImage dest(source.width() / 2, source.height() / 2, srcImage.format()); + dest.setDevicePixelRatio(source.devicePixelRatio()); + + const uchar *src = reinterpret_cast<const uchar*>(const_cast<const QImage &>(srcImage).bits()); + qsizetype sx = srcImage.bytesPerLine(); + qsizetype sx2 = sx << 1; + + uchar *dst = reinterpret_cast<uchar*>(dest.bits()); + qsizetype dx = dest.bytesPerLine(); + int ww = dest.width(); + int hh = dest.height(); + + for (int y = hh; y; --y, dst += dx, src += sx2) { + const uchar *p1 = src; + const uchar *p2 = src + sx; + uchar *q = dst; + for (int x = ww; x; --x, ++q, p1 += 2, p2 += 2) + *q = ((int(p1[0]) + int(p1[1]) + int(p2[0]) + int(p2[1])) + 2) >> 2; + } + + return dest; + } else if (source.format() == QImage::Format_ARGB8565_Premultiplied) { + QImage dest(source.width() / 2, source.height() / 2, srcImage.format()); + dest.setDevicePixelRatio(source.devicePixelRatio()); + + const uchar *src = reinterpret_cast<const uchar*>(const_cast<const QImage &>(srcImage).bits()); + qsizetype sx = srcImage.bytesPerLine(); + qsizetype sx2 = sx << 1; + + uchar *dst = reinterpret_cast<uchar*>(dest.bits()); + qsizetype dx = dest.bytesPerLine(); + int ww = dest.width(); + int hh = dest.height(); + + for (int y = hh; y; --y, dst += dx, src += sx2) { + const uchar *p1 = src; + const uchar *p2 = src + sx; + uchar *q = dst; + for (int x = ww; x; --x, q += 3, p1 += 6, p2 += 6) { + // alpha + q[0] = AVG(AVG(p1[0], p1[3]), AVG(p2[0], p2[3])); + // rgb + const quint16 p16_1 = (p1[2] << 8) | p1[1]; + const quint16 p16_2 = (p1[5] << 8) | p1[4]; + const quint16 p16_3 = (p2[2] << 8) | p2[1]; + const quint16 p16_4 = (p2[5] << 8) | p2[4]; + const quint16 result = AVG16(AVG16(p16_1, p16_2), AVG16(p16_3, p16_4)); + q[1] = result & 0xff; + q[2] = result >> 8; + } + } + + return dest; + } else if (source.format() != QImage::Format_ARGB32_Premultiplied + && source.format() != QImage::Format_RGB32) + { + srcImage = source.convertToFormat(QImage::Format_ARGB32_Premultiplied); + } + + QImage dest(source.width() / 2, source.height() / 2, srcImage.format()); + dest.setDevicePixelRatio(source.devicePixelRatio()); + + const quint32 *src = reinterpret_cast<const quint32*>(const_cast<const QImage &>(srcImage).bits()); + qsizetype sx = srcImage.bytesPerLine() >> 2; + qsizetype sx2 = sx << 1; + + quint32 *dst = reinterpret_cast<quint32*>(dest.bits()); + qsizetype dx = dest.bytesPerLine() >> 2; + int ww = dest.width(); + int hh = dest.height(); + + for (int y = hh; y; --y, dst += dx, src += sx2) { + const quint32 *p1 = src; + const quint32 *p2 = src + sx; + quint32 *q = dst; + for (int x = ww; x; --x, q++, p1 += 2, p2 += 2) + *q = AVG(AVG(p1[0], p1[1]), AVG(p2[0], p2[1])); + } + + return dest; +} + +#undef AVG +#undef AVG16 + +Q_GUI_EXPORT void qt_blurImage(QPainter *p, QImage &blurImage, qreal radius, bool quality, bool alphaOnly, int transposed = 0) +{ + if (blurImage.format() != QImage::Format_ARGB32_Premultiplied + && blurImage.format() != QImage::Format_RGB32) + { + blurImage = std::move(blurImage).convertToFormat(QImage::Format_ARGB32_Premultiplied); + } + + qreal scale = 1; + if (radius >= 4 && blurImage.width() >= 2 && blurImage.height() >= 2) { + blurImage = qt_halfScaled(blurImage); + scale = 2; + radius *= qreal(0.5); + } + + if (alphaOnly) + expblur<12, 10, true>(blurImage, radius, quality, transposed); + else + expblur<12, 10, false>(blurImage, radius, quality, transposed); + + if (p) { + p->scale(scale, scale); + p->setRenderHint(QPainter::SmoothPixmapTransform); + p->drawImage(QRect(QPoint(0, 0), blurImage.deviceIndependentSize().toSize()), blurImage); + } +} + +Q_GUI_EXPORT void qt_blurImage(QImage &blurImage, qreal radius, bool quality, int transposed = 0) +{ + if (blurImage.format() == QImage::Format_Indexed8 || blurImage.format() == QImage::Format_Grayscale8) + expblur<12, 10, true>(blurImage, radius, quality, transposed); + else + expblur<12, 10, false>(blurImage, radius, quality, transposed); +} + +QT_END_NAMESPACE |