old-nall/image/blend.hpp
2016-05-15 12:42:10 +02:00

72 lines
2.5 KiB
C++

#pragma once
namespace nall {
auto image::impose(blend mode, unsigned targetX, unsigned targetY, image source, unsigned sourceX, unsigned sourceY, unsigned sourceWidth, unsigned sourceHeight) -> void {
source.transform(_endian, _depth, _alpha.mask(), _red.mask(), _green.mask(), _blue.mask());
#pragma omp parallel for
for(unsigned y = 0; y < sourceHeight; y++) {
const uint8_t* sp = source._data + source.pitch() * (sourceY + y) + source.stride() * sourceX;
uint8_t* dp = _data + pitch() * (targetY + y) + stride() * targetX;
for(unsigned x = 0; x < sourceWidth; x++) {
uint64_t sourceColor = source.read(sp);
uint64_t targetColor = read(dp);
int64_t sa = (sourceColor & _alpha.mask()) >> _alpha.shift();
int64_t sr = (sourceColor & _red.mask() ) >> _red.shift();
int64_t sg = (sourceColor & _green.mask()) >> _green.shift();
int64_t sb = (sourceColor & _blue.mask() ) >> _blue.shift();
int64_t da = (targetColor & _alpha.mask()) >> _alpha.shift();
int64_t dr = (targetColor & _red.mask() ) >> _red.shift();
int64_t dg = (targetColor & _green.mask()) >> _green.shift();
int64_t db = (targetColor & _blue.mask() ) >> _blue.shift();
uint64_t a, r, g, b;
switch(mode) {
case blend::add:
a = max(sa, da);
r = min(_red.mask() >> _red.shift(), ((sr * sa) >> _alpha.depth()) + ((dr * da) >> _alpha.depth()));
g = min(_green.mask() >> _green.shift(), ((sg * sa) >> _alpha.depth()) + ((dg * da) >> _alpha.depth()));
b = min(_blue.mask() >> _blue.shift(), ((sb * sa) >> _alpha.depth()) + ((db * da) >> _alpha.depth()));
break;
case blend::sourceAlpha:
a = max(sa, da);
r = dr + (((sr - dr) * sa) >> _alpha.depth());
g = dg + (((sg - dg) * sa) >> _alpha.depth());
b = db + (((sb - db) * sa) >> _alpha.depth());
break;
case blend::sourceColor:
a = sa;
r = sr;
g = sg;
b = sb;
break;
case blend::targetAlpha:
a = max(sa, da);
r = sr + (((dr - sr) * da) >> _alpha.depth());
g = sg + (((dg - sg) * da) >> _alpha.depth());
b = sb + (((db - sb) * da) >> _alpha.depth());
break;
case blend::targetColor:
a = da;
r = dr;
g = dg;
b = db;
break;
}
write(dp, (a << _alpha.shift()) | (r << _red.shift()) | (g << _green.shift()) | (b << _blue.shift()));
sp += source.stride();
dp += stride();
}
}
}
}