Files
cbh/ElaWidgetTools/private/ElaExponentialBlurPrivate.cpp
2025-09-19 22:40:52 +08:00

103 lines
2.8 KiB
C++

#include "ElaExponentialBlurPrivate.h"
#include <QPixmap>
#if QT_VERSION < QT_VERSION_CHECK(6, 0, 0)
#include <cmath>
#endif
int ElaExponentialBlurPrivate::_aprec = 12;
int ElaExponentialBlurPrivate::_zprec = 7;
ElaExponentialBlurPrivate::ElaExponentialBlurPrivate(QObject* parent)
: QObject{parent}
{
}
ElaExponentialBlurPrivate::~ElaExponentialBlurPrivate()
{
}
void ElaExponentialBlurPrivate::_drawExponentialBlur(QImage& image, const quint16& qRadius)
{
if (qRadius < 1)
{
return;
}
image = image.convertToFormat(QImage::Format_ARGB32_Premultiplied);
int alpha = (int)((1 << _aprec) * (1.0f - std::exp(-2.3f / (qRadius + 1.f))));
int height = image.height();
int width = image.width();
for (int row = 0; row < height; row++)
{
_drawRowBlur(image, row, alpha);
}
for (int col = 0; col < width; col++)
{
_drawColumnBlur(image, col, alpha);
}
}
void ElaExponentialBlurPrivate::_drawRowBlur(QImage& image, const int& row, const int& alpha)
{
int zR, zG, zB, zA;
QRgb* ptr = (QRgb*)image.scanLine(row);
int width = image.width();
zR = *((unsigned char*)ptr) << _zprec;
zG = *((unsigned char*)ptr + 1) << _zprec;
zB = *((unsigned char*)ptr + 2) << _zprec;
zA = *((unsigned char*)ptr + 3) << _zprec;
for (int index = 0; index < width; index++)
{
_drawInnerBlur((unsigned char*)&ptr[index], zR, zG, zB, zA, alpha);
}
for (int index = width - 2; index >= 0; index--)
{
_drawInnerBlur((unsigned char*)&ptr[index], zR, zG, zB, zA, alpha);
}
}
void ElaExponentialBlurPrivate::_drawColumnBlur(QImage& image, const int& column, const int& alpha)
{
int zR, zG, zB, zA;
QRgb* ptr = (QRgb*)image.bits();
ptr += column;
int height = image.height();
int width = image.width();
zR = *((unsigned char*)ptr) << _zprec;
zG = *((unsigned char*)ptr + 1) << _zprec;
zB = *((unsigned char*)ptr + 2) << _zprec;
zA = *((unsigned char*)ptr + 3) << _zprec;
for (int index = width; index < (height - 1) * width; index += width)
{
_drawInnerBlur((unsigned char*)&ptr[index], zR, zG, zB, zA, alpha);
}
for (int index = (height - 2) * width; index >= 0; index -= width)
{
_drawInnerBlur((unsigned char*)&ptr[index], zR, zG, zB, zA, alpha);
}
}
void ElaExponentialBlurPrivate::_drawInnerBlur(unsigned char* bptr, int& zR, int& zG, int& zB, int& zA, int alpha)
{
int R, G, B, A;
R = *bptr;
G = *(bptr + 1);
B = *(bptr + 2);
A = *(bptr + 3);
zR += (alpha * ((R << _zprec) - zR)) >> _aprec;
zG += (alpha * ((G << _zprec) - zG)) >> _aprec;
zB += (alpha * ((B << _zprec) - zB)) >> _aprec;
zA += (alpha * ((A << _zprec) - zA)) >> _aprec;
*bptr = zR >> _zprec;
*(bptr + 1) = zG >> _zprec;
*(bptr + 2) = zB >> _zprec;
*(bptr + 3) = zA >> _zprec;
}