In Line 3 of Algorithm 1, is the notation of $x_t$ and $o$ reversed? If it is the dot product between the view direction (from camera to intersection) and the normal, then the initial result in Figure 4 would be negative, causing the loop to exit immediately.
In Line 3 of Algorithm 1, is the notation of$x_t$ and $o$ reversed? If it is the dot product between the view direction (from camera to intersection) and the normal, then the initial result in Figure 4 would be negative, causing the loop to exit immediately.