Problem about the "distortion loss"

[Yukun66]

Hi kwea123! I have a question about line 94 in the loss.cu code. According to the method in Improved Direct Voxel Grid Optimization for Radiance Fields Reconstruction, the forward pass of distortion loss is composed of 2 parts, for example, there are 3 points, w0, w1, w2, and m0, m1, m2. The integration is going to be:

w1w0(m1-m0) + [w2w0(m2-m0)+w2w1(m2-m1)] 
=[w1m1w0+(w2m2w0+w2m2w1)]- [w1w0m0 + (w2w0m0+w2w1m1)]
=[0 + (w1m1)w0+(w2m2)(w0+w1)]- [0+w1(w0m0) + w2(w0m0+w1m1)]
=(wts * ws_exclusive_scan- ws *wts_exclusive_scan)

But in your code, it is: (lines 94-96)

integration = (wts_inclusive_scan*ws_exclusive_scan-
                    ws_inclusive_scan*wts_exclusive_scan)

It's different from my toy example. Could you please help me out? Thx!