void Image_VGA_Planar::convert(const Pixels& newContent,
const Pixels& newMask)
{
auto dims = this->dimensions();
unsigned long dataSize = dims.x * dims.y;
stream::pos len = this->content->size();
// Cut off any leftover data or resize so there's enough space
if (dataSize + this->off != len) {
this->content->truncate(dataSize + this->off);
} // else size didn't need to change, e.g. fixed-size VGA image
Pixels pix;
pix.resize(dataSize, 0);
// Convert the linear data to planar
unsigned int planeWidth = dims.x / 4;
unsigned int planeSize = planeWidth * dims.y;
for (unsigned int i = 0; i < dataSize; i++) {
pix[i] = newContent[i % planeSize * 4 + i / planeSize];
}
this->content->seekp(this->off, stream::start);
this->content->write(pix.data(), dataSize);
return;
}
