FGU LOS is wrong

[Rafael Martins]

The way the FGU calculates LOS is not in accordance with the rules in DMG page 251, which says: "To precisely determine whether there is line of sight between two spaces, pick a corner of one space and trace an imaginary line from that corner to any part of another space. If at least one such line doesn't pass through or touch an object or effect that blocks vision such as a stone wall, a thick curtain, or a dense cloud of fog-then there is line of sight. "
As illustrated in figure 01 (DM's view) the Troll should benefit from half cover, as we can draw two lines starting from the Player's token to one corner of the NPC's token. However, FGU considers only one line starting from the center of the square, causing the Troll to be mistakenly considered under full cover, as we can see in figure 02 (Player's view).

[Sulimo]

This was discussed previously (https://www.fantasygrounds.com/forums/showthread.php?52439-Current-LoS-and-how-it-calculates-has-an-inherent-problem&p=465218&viewfull=1#post465218).

I do not recall seeing a solution. Part of the issue is that each ruleset may calculate LoS differently, so FG needs to be somewhat flexible to accommodate different rulesets.

[pindercarl]

Thanks for reporting. The troll should be visible in that scenario. There is a bug with the token visibility checks that will need to be corrected. However, the visibility checks (when functioning correctly) do not precisely match the 5E description. FGU checks token visibility if the center, or any corner of the token, is visible from the center of the viewer.

[Rafael Martins]

Thank you very much for your support

[klimkin]

This is the same issue in for Pathfinder 2E. Is there any chance to add an option to calculate LOS according to 5E/Pathfinder2E rules? In particular:
1. Make LOS area calculations not from the centers, but from the corners of the square. The area is wider compared to just from the center.
2. Change token visibility if any part of the creature square is in the LOS area.