As far as I know you only need to link one of your target's corners with one of yours, not two.
In the PRD (Core book) there is the chapter combat which mentions line of sight and line of effect several times Core Book
When you have line of effect nothing is in the way between you and your target. It is used to determine if an enemy has cover for example.
To determine whether your target has cover from your ranged attack, choose a corner of your square. If any line from this corner to any corner of the target's square passes through a square or border that blocks line of effect or provides cover, or through a square occupied by a creature, the target has cover (+4 to AC).
If you have line of sight there is nothing obstrucing your view in a similar manner.
You don't need to reach any corner, specifically. Page 215 of the Core Rulebook has the rules (Can't link at work, or read the link above).
Following the example of a 1' hole in a 5' wall section, you could not draw a line to any of the corners, but you would still have line of effect.
Line of effect is not cover. While cover can affect the attack roll involved, anything less than full cover will not stop line of effect.
Line of Sight works the same way, but only includes sight. For instance, if a wall of force is between you and your opponent, you have line of sight because you can see them. You do not have Line of Effect because there is a physical barrier blocking the two of you.
So, you can't cast magic missle through the Wall of Force, but if you cast an illusion on your side of the wall, your enemy can still see it.
Yes to the first part. Yes to the second part, the attacker gets to choose which corner to start from and MUST test to each corner of the target's square.
Happy Gaming!
Does an invisible wall such as wall of force block line of effect?
Can someone direct me to where line of sight is defined? Funny thing is you need line of sight to charge but I can't find what line of sight is and what counts as a "solid barrier". Does a PC or enemy count as a solid barrier?
Does an invisible wall such as wall of force block line of effect?
Can someone direct me to where line of sight is defined? Funny thing is you need line of sight to charge but I can't find what line of sight is and what counts as a "solid barrier". Does a PC or enemy count as a solid barrier?
Line of effect would be blocked by a wall of force.
http://www.d20pfsrd.com/basics-ability-scores/glossary#TOC-Line-of-Sight
You will find these under Common Terms in the front of the CRB:
Page 215, Line of Effect:
A line of effect is a straight, unblocked path that indicates what a spell can affect. A line of effect is canceled by a solid barrier. It's like line of sight for ranged weapons, except that it's not blocked by fog, darkness, and other factors that limit normal sight.
You must have a clear line of effect to any target that you cast a spell on or to any space in which you wish to create an effect. You must have a clear line of effect to the point of origin of any spell you cast.
A burst, cone, cylinder, or emanation spell affects only an area, creature, or object to which it has line of effect from its origin (a spherical burst's center point, a cone-shaped burst's starting point, a cylinder's circle, or an emanation's point of origin).
An otherwise solid barrier with a hole of at least 1 square foot through it does not block a spell's line of effect. Such an opening means that the 5-foot length of wall containing the hole is no longer considered a barrier for purposes of a spell's line of effect.
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There does not seem to be a great, all-powerful definition of Line of Sight. Apparently, the authors planned that we would just use the general definition in the English language - if you can see it, you have line of sight, if you can't, you don't. There are bits in the CRB about fog and darkness blocking line of sight, which fits the English definition.
I would say that if a target has Total Concealment then you don't have line of sight, but I didn't see that anywhere in the CRB.
So I have a character who lives in space, rarely teleporting to the surface. Teleport defines “Studied carefully” as a place you know well, either because you can currently physically see it or you've been there often. I've been digging through threads dating back to 09 and it seems that, on a clear day, I should be able to teleport to any square not otherwise obstructed by trees as if I could see it, though obviously it would be way to far away.
I could see a house rule being that you teleport to an area as with plane shift (5-500 miles) to make this more realistic, but my GM goes for the rules as stated even when they're off the wall.
Anyone see any issues with teleporting from space to a specific square I can 'see'?
Yes... unless you're using the spell Interplanetary Teleport, you can't teleport to or from space. So you're already deep into house rule territory.
I have my doubts this is a real situation.
You can see the planet as it is a feature. However, to teleport to a specific square, you need to see it, and to do that you need to make out the details, so you would need to make a Perception check to identify the exact location you wanted to appear in (DC 0 + 1 * n, where n = number of squares between you and your target square).