void ImageSampler::DoPixelSampling(UINT32 x, UINT32 y, UINT32 sample_count, PixelSamplingResult& result)
{
IntersectContext tempCtx;
if (mTempSamplingRes.size() < sample_count)
mTempSamplingRes.resize(sample_count);
float sampleCnt = (float)sample_count;
float hitCnt = 0;
KColor sum(0,0,0);
RenderBuffers* pRBufs = mpInputData->pRenderBuffers;
for (UINT32 si = 0; si < sample_count; ++si) {
TracingInstance& tracingInst = *mTracingThreadData.get();
tracingInst.mCameraContext.inScreenPos = pRBufs->RS_Image(x, y);
float motionTime = ENABLE_MB ? pRBufs->RS_MotionBlur(x, y) : 0;
tracingInst.mCameraContext.inMotionTime = motionTime;
tracingInst.mCameraContext.inAperturePos = ENABLE_DOF ? pRBufs->RS_DOF(x, y) : KVec2(0,0);
KColor out_clr;
bool isHit = mpInputData->pCurrentCamera->EvaluateShading(tracingInst, mTempSamplingRes[si]);
sum.Add(mTempSamplingRes[si]);
mpInputData->pRenderBuffers->IncreaseSampledCount(x, y, 1);
if (isHit)
hitCnt += 1.0f;
}
result.alpha = hitCnt / sampleCnt;
result.variance = 0;
result.average = sum;
result.average.Scale(1.0f / sampleCnt);
for (UINT32 si = 0; si < sample_count; ++si) {
result.variance += mTempSamplingRes[si].DiffRatio(result.average);
}
result.variance /= sampleCnt;
}
