What happens if an object is too big for a portal?

[ríomhaire]

This just poped into my head. What do you think would happen if you tried to drop an item that was too big into a portal?

 

[jimmyjam]

What happens if an object is too big for a hole?
This just popped into my head. What do you think would happen if you tried to drop an item that was too big into a hole?

 

[Max35]

Playtesting will sort out any bugs I'm sure. Or maybe not. I'm thinking that the portal gun will "jam" if that occurs.

 

[ríomhaire]

What happens if an object is too big for a hole?
This just popped into my head. What do you think would happen if you tried to drop an item that was too big into a hole?

It would get blocked by the solid mass around the hole but if a portal is in mid-air then there won't be solid matter around it. A hole in nothing. Nothing to stop it falling. I suppose in real life it woud get cut at the boarder of the boundry but Source can't do that.


What I was actually thinking when I came up with this was putting the gun into HL2 (and making other changes too to acomidate it like making bullets actualy physics objects). I was thinking that it might be unfair as you could skip large parts of levels. Then the train-bridge poped into my head as an example and then I thought "What if a train hit a portal?"

 

[jimmyjam]

if it is an extension of narbacular drop as people have said, then the portals can only exist on solid surfaces and never float in the air

and even if it isn't it certainly seems to be inspired by it

 

[ríomhaire]

That explains it so. I hope there's soldiers in Portal, or at least someone does port it to HL2/EP1/EP2.

Imagine, a soldier's running at you, you make a portal on the ground under him and another on the side of a building, he falls through, out the side of the building and lands on some more soldiers
Or being able to send antlions through a portal behind combine soldiers.

You would have to modify the weapons so they were all physics objects to get the best out of it though (as it stands only grenades are physics objecsts)

 

[Max35]

Man, the CPU reqs for this are gonna be steep. Unless one doesn't mind frequent crashes.

 

[The Brick]

Ehm I don't think it's gonna be very cpu intensive. Not other than hl2's physics were. It might crash your brain though.

 

[AzzMan]

Prey didnt slow down my computer at all, dont see why this would...

 

[Cole]

If there are enemies could you put a portal up then the enemy shoots into the portal, and you have the portal come out behind him...would the bullet go through the portal and hit him?
That would be awesome!

 

[The Brick]

Yes if you would have guns! Which I think you don't. It's a puzzle game.

 

[ríomhaire]

If there are enemies could you put a portal up then the enemy shoots into the portal, and you have the portal come out behind him...would the bullet go through the portal and hit him?
That would be awesome!

I don't think so. You see, bullets arn't physics objects, they instantly hit (the tracers are only effects). But maybe you could programme portals to do so. And if jimmyjam is right then we'll only be able to put them on walls, cielings and floors so you'd have to make the soldier shoot at a wall. Though if there is a corner you might be able to set portals up so you could shoot around the corner (and if AI was programmed well maybe soldiers would shoot through them too.

 

[myth]

of course the object gets teliported. there is no doubt abt it.

for example: freeman dont have to be in the centre of the portal to get teleported. the played just need to touch it.

 

[ríomhaire]

But bullets aren't objects in HL2, there're just effects. You basicly click the mouse and damage appears where you were pointing.

 

[ZoFreX]

It's by the same people as "Narbacular Drop", which is a puzzle game. You can ND here: http://www.nuclearmonkeysoftware.com/narbaculardrop.html

I believe Valve announced Portal as a puzzle game too, so it'll probably be pretty similar... except hopefully about 10 times the frame rate, ND is a bit slow. And with regards to the original post... you can only create portals on solid surfaces in ND.

 

[The Brick]

Riomhaire, what would that have to do with the question whether they go through teleporters? Myth, teleporters are not the 'zoom you're somewhere else' ones. You can just slowly walk through them like a door, with a part of you sticking out of the other side.

Have you actually played Narbacular drop? Did you notice how the teleporters work? When you make a teleporter, the game copies the room that you are in and sticks it to the other side with the point where the other teleporter is. It gives you the illusion that you actually teleport to somwhere else, but basically you walk into the copy of the same room. Even when you see yourself, it's just a copy.

 

[ríomhaire]

Riomhaire, what would that have to do with the question whether they go through teleporters? Myth, teleporters are not the 'zoom you're somewhere else' ones. You can just slowly walk through them like a door, with a part of you sticking out of the other side.

Have you actually played Narbacular drop? Did you notice how the teleporters work? When you make a teleporter, the game copies the room that you are in and sticks it to the other side with the point where the other teleporter is. It gives you the illusion that you actually teleport to somwhere else, but basically you walk into the copy of the same room. Even when you see yourself, it's just a copy.

That's damn cool, I've got to download it when I can. Though it sounds like too many portals would eat your RAM since you have to have copies of the room a load of time. I'm sure Valve will pull through though

 

[ZoFreX]

Yeah, ND did hurt my computer quite a bit, the frame rate was very low - although hopefully Portal will be on Source (I'm kind of assuming it will, any news on this?) which is far more optimised than whatever ND is running on. I'm sure having a copy of the room is not necessary, Unreal Tournament manages portals almost as complete and I'm sure it wouldn't take much hacking to implement them without a total copy operation in any engine.

 

[jimmyjam]

The Brick: you don't seem to understand how portal technology works
the whole thing about objects just going through? that's a trick of the eye. If guns were to shoot through the portal, the code would need to be changed so that each bullet is physically modelled instead of using hitscan (which would slow down the game considerably)
this is what prey does (except for the sunbeam and lightning gun.. they're still hitscan and can't go through portals)

 

[Epsi]

There's no reason a hitscan weapon couldn't go through a portal. You'd just have to have a bit of code to draw another trace on the other side of the portal when a hitscan trace happened to hit a portal.

 

[jimmyjam]

of course it's possible, and I wouldn't be outstandingly surprised if portal did it, but I'd still put money on the fact that it won't

 

[Kyorisu]

ND ran smooth for me I didn't notice any slow downs running at 1600x1200 and my rig isn't anything special.

Really though. Shoot bullet - draw a line - line intersects a portal - Draw a line from the connecting portal and in the same direction as the original line - line intersects foe - damage foe.

 

[Cyber$nake]

well if the portal is like a black hole then it should kinda get sucked in anyways...and then for video game reasons, have it "reform" once it gets out th e other side...kinda hard to explain what i mean.

 

[Iced_Eagle]

If there's guns I will place money that bullets WILL go through the portal.

What you need to understand is yes technically when you click the mouse it just does damage to the thing you're pointing at, but how it does that it just draws a line. Now let's say you have a portal in front of you, it draws the line out from your gun, and it intersects the portal, and then at the receiving end, it copies the vector (direction the line was pointing) and the line continues until it hits something... Hell, you can hit yourself in the back possibly!

Trust me it's possible and in fact they do it in Narbacular Drop except instead of it being with bullets its with portals... You can place one portal down and then a second and can create sub-seqeunt portals by looking through them (really confusing concept, but basically it's just creating portals by looking through other portals)... Anyways, it checks to see if a portal can be created by drawing a line, same concept as firing a gun... It goes through portals just fine and I guarantee you that Portal will do the same.

this is what prey does

Prey uses the Doom3 engine which uses Hitscan (same as HL2). The only difference (and the one I'm guessing you are confusing with) is that Doom3 (and thus Prey) uses per-poly hit detection, which doesn't really matter though in this argument.

Even when you see yourself, it's just a copy.

Once again, it's not It's just a trick with cameras. At each portal it just has an outward facing camera that always orients itself with the portal, not the world (which is why even when you place a portal upside down, when you look at it through the other portal it looks "normal")... Each portal simply displays the other portal's camera output.

the played just need to touch it.

I'm fairly certain that players will be able to sit in-between two portals... You can do it in Narb. Drop, and I'm sure that they will do it for Portals.

Man, the CPU reqs for this are gonna be steep. Unless one doesn't mind frequent crashes.

No, if anything it will be GPU intensive... Imagine staring at a wall, and then have the two portals in front of you... If you can see past the wall it has to draw everything in front of you, and behind you which sort of defies the point of doing camera clipping (where if something is outside the camera FOV, don't bother drawing it)... Luckily, the portal viewing area isn't going to be huge, so it won't have to draw the _entire_ scene over, but still, this game probably won't have any different set of req's than HL2.

well if the portal is like a black hole then it should kinda get sucked in anyways...and then for video game reasons, have it "reform" once it gets out th e other side...kinda hard to explain what i mean.

I know exactly what you mean, and it's totally possible for a player to sit in-between portals (it's in Narb. Drop which merely demonstrates that it's not technically impossible)... Now perhaps if they change the story so these things are similar to blackholes (I doubt they are, and it will be like Narb. Drop)

 

[99.vikram]

Prey uses the Doom3 engine which uses Hitscan (same as HL2)

Doom 3 doesn't support per pixel hit-detection? :O
That's new to me.

 

[Iced_Eagle]

Doom 3 doesn't support per pixel hit-detection? :O
That's new to me.

Read the next sentence and come talk to me again.... Seriously man one more sentence you had to read...

You guys are getting collision detection and hitscan screwed up...

Hitscan is simply drawing a line, and then when it intersects player, that's when you use the collision types (in HL2, bounding boxes, for Doom3 per-poly)

 

[ZoFreX]

I'd put good money on Portal not having guns at all.

On a technical note, yes, you could implement portal traversal with hitscan, but I could crash any game doing it by firing a volley into two looping portals - eventually they'll hit something but it might be a few thousand iterations before they do, could be pretty cpu intensive.

If you have two looping portals and even look through them, that's gonna be funtime for the graphics card (kinda like standing between two mirrors... ooh, gotta try that in HL2).

How did you get it to 1600x1200 btw? On my machine the max was 1024x768 (and my lcd is 1280x1024, grr).

 

[jimmyjam]

Iced Eagle you are making my own argument for me, thanks

 

[Iced_Eagle]

Iced Eagle you are making my own argument for me, thanks

How am I doing that? I seem to be doing the opposite. In fact I'll do it again.

If guns were to shoot through the portal, the code would need to be changed so that each bullet is physically modelled instead of using hitscan (which would slow down the game considerably)

This is completely false. Hitscan is simply drawing a line! You don't think they can draw a line through a portal? They don't have to change how bullets are handled in any way.

this is what prey does (except for the sunbeam and lightning gun.. they're still hitscan and can't go through portals)

I can shoot through portals with my rifle in Prey, and it uses hitscan for all weapons (exception being obviously projectiles like rockets and grenades and such, and even these go through portals)... Don't bring per-poly hit detection into this as you guys seem to be doing, as that is a type of collision detection and is irrelevant to the point at hand.

*edit*

On a technical note, yes, you could implement portal traversal with hitscan, but I could crash any game doing it by firing a volley into two looping portals - eventually they'll hit something but it might be a few thousand iterations before they do, could be pretty cpu intensive.

When you say firing a volley, do you mean like a grenade? They could simply just add a timer (once it goes through the portal entity it should explode when it touches something or after 5 seconds, or possibly after it reaches a certain velocity). For bullets, they could do maximum line length or something similar.

How did you get it to 1600x1200 btw?

In Half-Life 2 do you mean? In Steam right click on Half-Life 2, Properties, Launch Options and then type -width 1600 -height 1200 or whatever you want.

 

[ríomhaire]

When you say firing a volley, do you mean like a grenade? They could simply just add a timer (once it goes through the portal entity it should explode when it touches something or after 5 seconds, or possibly after it reaches a certain velocity). For bullets, they could do maximum line length or something similar.

He means a volley of bullets. As in Stand in between 2 portals, shoot and then realise that your logic is flawed as and bullets that don't hit you are going to be so off target that they'll only 2 about 2 laps through the portals.

 

[Cole]

Doom 3 doesn't support per pixel hit-detection? :O
That's new to me.

Doom 3 uses Per Polygon Hit Detection.

 

[tehsolace]

In ND and in the trailer for Portal, we witnessed being able to "shoot" through a portal and it's trajectory continues just fine.

Remember - the portal gun shoots an actual model (a purple blob), not unlike the overwatch rifle shoots the energy balls. The model's path continues through the portal and through it just fine.

 

[ZoFreX]

The portal guns fire in Portal is a modelled object, as you can see it move - it's not hitscan. Things that move at less than infinite metres per second wouldn't be such a problem if they got into a near infinite loop, which you could probably still get close to with a hitscan.

And I meant, how to get 1600x1200 in ND.

 

[ríomhaire]

And I meant, how to get 1600x1200 in ND.

Do you have a 1600x1200 moniter & GFX card?

 

[Iced_Eagle]

And I meant, how to get 1600x1200 in ND.

Well, I doubt that you could make that happen.

TBH, it's a senior project at school, so you can get really unexpected behavior if you go beyond what they show in the options menu... It's not as robust as retail games are.

 

[Epsi]

Although in theory, if you fired a bullet dead perpendicular to the portal through a pair of portals that was set up in an infinite loop scenario, it would loop forever, and the game would lock up.

In practice, if you fired a bullet dead perpendicular, you'd shoot yourself, which resolves some of the paradoxes. Otherwise, you'd just need to introuduce a time-to-live factor into the hitscan calculations. Each time the hitscan trace line had to traverse a portal, you decrease the time-to-live by 1 and once it hit 0, you stop tracing.

 

[ZoFreX]

Well, I doubt that you could make that happen.

He managed:

ND ran smooth for me I didn't notice any slow downs running at 1600x1200 and my rig isn't anything special.

Hence I asked:

How did you get it to 1600x1200 btw? On my machine the max was 1024x768 (and my lcd is 1280x1024, grr).

Do you have a 1600x1200 moniter & GFX card?

Negative to the monitor but I really want 1280x1024, cos that's my lcd's native res.

Although in theory, if you fired a bullet dead perpendicular to the portal through a pair of portals that was set up in an infinite loop scenario, it would loop forever, and the game would lock up.

In practice, if you fired a bullet dead perpendicular, you'd shoot yourself, which resolves some of the paradoxes. Otherwise, you'd just need to introuduce a time-to-live factor into the hitscan calculations. Each time the hitscan trace line had to traverse a portal, you decrease the time-to-live by 1 and once it hit 0, you stop tracing.

If the bullet was in a true infinte loop you could just create a static thin line of hit damage where its path is, so if you walk into its path then it hits you, wouldn't be intense on the cpu at all. Or you could physically model it so it goes so far per second, that's probably slightly better than hitscan.

 

[ríomhaire]

If the bullet was in a true infinte loop you could just create a static thin line of hit damage where its path is, so if you walk into its path then it hits you, wouldn't be intense on the cpu at all.

I don't think it would work like that. More like the path is calculated over and over again in an infinate loop and anything being run over and over infinatly, nomatter how small would crash your computer

Or you could physically model it so it goes so far per second, that's probably slightly better than hitscan.

It'd be more CPU intensive though.

 

[ZoFreX]

I don't think it would work like that.

It could work like that if you wanted it to, is my point

anything being run over and over infinatly, nomatter how small would crash your computer

Not if it's threaded

It'd be more CPU intensive though.

Possibly, but shouldn't crash your computer in the infinite loop scenario.

 

[W4E]

They probably wont have guns to avoid all these problems.