void write_image(const string& file, const SampleBuffer& buffer)
{
const float samples = static_cast<float>(buffer.samples());
FIBITMAP* dib = FreeImage_Allocate(buffer.width(), buffer.height(),
32, FI_RGBA_RED_MASK, FI_RGBA_GREEN_MASK, FI_RGBA_BLUE_MASK);
const unsigned int BYTESPP =
FreeImage_GetLine(dib) / FreeImage_GetWidth(dib);
for (unsigned int y = 0; y < FreeImage_GetHeight(dib); ++y) {
BYTE* bits = FreeImage_GetScanLine(dib, y);
for (unsigned int x = 0; x < FreeImage_GetWidth(dib); ++x) {
vec3 c = gamma_correct(buffer.get(x, y) / samples) * 255.0f;
bits[FI_RGBA_RED] = static_cast<BYTE>(c.r);
bits[FI_RGBA_GREEN] = static_cast<BYTE>(c.g);
bits[FI_RGBA_BLUE] = static_cast<BYTE>(c.b);
bits[FI_RGBA_ALPHA] = 255;
bits += BYTESPP;
}
}
if (!FreeImage_Save(FIF_PNG, dib, file.c_str(), 0)) {
string err = "Failed to save screenshot to file '";
err += file;
err += '\'';
throw err;
}
FreeImage_Unload(dib);
}
void SampleBuffer::append(const SampleBuffer& other)
{
assert(width() == other.width() && height() == other.height());
auto it = _buffer.begin();
auto io = other._buffer.cbegin();
while (it < _buffer.cend()) {
*it += *io;
++it;
++io;
}
_samples += other.samples();
}
