Light radius confusion

[Weissrolf]

To create a token light with 20" radius (4 grid squares in every direction around the token) I need to create a 22.5" sized light, else the light ends on a half-grid. So light radius is measured from the center of a token, not from its sides.

Is this intentional?

[Zacchaeus]

Yes.

[damned]

it should measure from the centre of the token.

[Weissrolf]

Ok, it seems to work different to other VTTs and to how people handle light at a table, but thanks for clarifying the intention. I assume it is also intentional then that the light presets do not visually match the rules of DND 5E or Pathfinder (1&2)?

[Zacchaeus]

They do in fact represent the rules as far as I can tell. A torch for example sends out light in a 20ft. radius. So if you measure out 20ft. from the centre point of any one square then it will reach out that far into the middle of all the squares 20ft away. There is nothing that I can see anywhere that says the light point starts at the edge of the grid square that the PC is standing in which I'm assuming is your house rule. But we can argue about that to here and back again so let's not bother. Suffice to say if you want light to go 22.5 ft instead of 20 then make sure that you create the appropriate effects.

[Moon Wizard]

Also, that means that torches held by ogres are actually shedding light to 27.5 ft. with that house rule. The center point implementation implies a fixed distance, whereas an edge-based implementation implies a variable distance for light sources based on creature size.

Regards,
JPG

[anathemort]

It might be worth considering spell targets too, where a sphere is always centered on a point (as opposed to a shape like a cube which is on an edge), and I think that matches the shape of a typical light source. Revealing half a standard grid square should be enough to reveal a (5e Medium) creature within as you're seeing up to the center of it, anyway.

[Weissrolf]

The point of origin for the light is an object (torch), not the center of the Ogre's heart. But even it it was then Ogres "control a space" 10 ft "wide". D20 games don't use facing and any creature can hold their shields, weapons or torches to any side and point of the space they control at any time (unless hindered).

Furthermore the 5E DMG asks to "choose an intersection of squares" as point of origin for areas of effect when grids are used, that would be the four corners of the token square. If you put four circles on all four corners then their combined area equals a circle about 2.5" larger (aka distance from the edges of a token). So measuring from the sides of a token would make things easier and be within the rules.

Then there are other (D20) grid based games that tend to count full grid squares instead of using more free floating forms like circles and cones of 5E, the latter of which being based on non-grid game-play to begin with. Having distances end in half-squares is inconvenient and a bit unattractive for these other systems. And with the 5E rule of "circular" area covering "at least half a square" = affecting that square it would make sense to make that visible even if you insist the point of origin being the center of a token square.

Coming back to the presets: The torch ends at 45 dim and the lantern at 65 dim, which means that they currently reveal tokens 2.5" further away than they should (aka too early). This can reveal tokens during (especially diagonal) movement that should still be hidden by darkness. Not a big thing, but if you insist on 2.5" at the point of origin (arguable) then you should also apply the same precision at the far end.

[Zarestia]

The point of origin for the light is an object (torch), not the center of the Ogre's heart. But even it it was then Ogres "control a space" 10 ft "wide". D20 games don't use facing and any creature can hold their shields, weapons or torches to any side and point of the space they control at any time (unless hindered).

This is a pen & paper / VTT game, not a simulator. If you want hyper-realism in your games, use either your imagination (what people have done since the 70's) or suggest somehting like a light<->token attacher. Then you can move your torch to your forearm or shield. Be extra careful when you move your forearm, as the torch moves too.

Furthermore the 5E DMG asks to "choose an intersection of squares" as point of origin for areas of effect when grids are used, that would be the four corners of the token square. If you put four circles on all four corners then their combined area equals a circle about 2.5" larger (aka distance from the edges of a token). So measuring from the sides of a token would make things easier and be within the rules.

This is for miniatures, not tokens. Areas of effect are specifically for spells (fireball and co.). This is atleast for 3.5E, Pathfinder & Starfinder afaik.

Then there are other (D20) grid based games that tend to count full grid squares instead of using more free floating forms like circles and cones of 5E, the latter of which being based on non-grid game-play to begin with. Having distances end in half-squares is inconvenient and a bit unattractive for these other systems. And with the 5E rule of "circular" area covering "at least half a square" = affecting that square it would make sense to make that visible even if you insist the point of origin being the center of a token square.

Coming back to the presets: The torch ends at 45 dim and the lantern at 65 dim, which means that they currently reveal tokens 2.5" further away than they should (aka too early). This can reveal tokens during (especially diagonal) movement that should still be hidden by darkness. Not a big thing, but if you insist on 2.5" at the point of origin (arguable) then you should also apply the same precision at the far end.

I count 8 squares (if rounding up half squares) from my medium token (which most players are in fantasy rulesets, bigger often have additional visions) to the north, east, south and west. I of course don't count the light in my space, because on a tabletop you can always see your token, otherwise you can't move it.

As there is no clear ruling we can discuss this for another 10 pages, probably not changing anyhting

Probably already on SW's radar, but I think later down the line custom saveable presets would clear up many things like this, then every GM/DM can rule it how he/she/it feels like.

[ddavison]

I think you can just add half of the token space/size to your light definition. Moon Wizard is working on some configuration screens where you can edit the default values for the presets.