UFO:Alien Invasion

Technical support => Feature Requests => Topic started by: sys64768 on January 11, 2012, 04:49:24 pm

Title: Damage buildings/wall by rockets and/or explosives
Post by: sys64768 on January 11, 2012, 04:49:24 pm
Hello, in the 2.2 version it is not possible to open a "passage" in a wall using rockets or explosive.
I don't know if in the 2.3 release this feature is implemented or not.

This is my suggestion for the new release.

Max
Title: Re: Damage buildings/wall by rockets and/or explosives
Post by: geever on January 11, 2012, 09:14:43 pm
Hello, in the 2.2 version it is not possible to open a "passage" in a wall using rockets or explosive.
I don't know if in the 2.3 release this feature is implemented or not.
This is my suggestion for the new release.

It won't happen anytime. Our 3D engine doesn't support destructible terrain, and changin' engine would kill the project for sure. (Just one element: every map should be redrawn for such a change)

-geever
Title: Re: Damage buildings/wall by rockets and/or explosives
Post by: nuudle on February 01, 2012, 05:08:41 pm
It won't happen anytime. Our 3D engine doesn't support destructible terrain, and changin' engine would kill the project for sure. (Just one element: every map should be redrawn for such a change)
I believe it is possible. And I am sure, it won't require the maps be redrawn.
Title: Re: Damage buildings/wall by rockets and/or explosives
Post by: geever on February 01, 2012, 05:12:44 pm
I believe it is possible. And I am sure, it won't require the maps be redrawn.

Go for it! Patches are welcome as always!

-geever
Title: Re: Damage buildings/wall by rockets and/or explosives
Post by: nanomage on February 02, 2012, 10:22:59 am
Just for interest, geever, how are destructible windows and fences done at the moment?
I recall I was so much glad to see windows shatter in 2.4. I thought "Wow looks like the guys are making their way towards destructible terrain". Too bad it's still not going to happen.
Also, is it at all possible to have maps being "pre-destructed" by UFO crashes, so that a part of the map where the UFO crashlanded would be damaged and ignited in some procedurally generated way?
Title: Re: Damage buildings/wall by rockets and/or explosives
Post by: H-Hour on February 02, 2012, 11:42:03 pm
Also, is it at all possible to have maps being "pre-destructed" by UFO crashes, so that a part of the map where the UFO crashlanded would be damaged and ignited in some procedurally generated way?

No. Arisian dove into our engine a year or so ago to do a lot of work on it, but his conclusion in the end was that it would essentially have to be rewritten from scratch to really implement destructible terrain.

I don't think it will ever happen with UFO:AI, but if it ever did, it would almost certainly not happen for years.
Title: Re: Damage buildings/wall by rockets and/or explosives
Post by: iamaloner on March 12, 2012, 04:11:24 pm
The game is influenced by XCOM/UFO:Enemy Unknown ... There should be destructible terrains...

Anyway most maps I see needs some changes... or removed because they were made a long time ago like 2 years tops... Or less...

If terrain was partialy destroyable then it would make game more intense... Atleast some parts like:
- Doors
- Windows
- Some walls
- objects (computer, monitor, chair...)
- vehicles (most of them)

Remaking maps is long and painfull job but it would allow remaking them and making them better, atleast a reason to redo the map and improve most of things...
Title: Re: Damage buildings/wall by rockets and/or explosives
Post by: geever on March 12, 2012, 04:45:31 pm
The game is influenced by XCOM/UFO:Enemy Unknown ... There should be destructible terrains...

Anyway most maps I see needs some changes... or removed because they were made a long time ago like 2 years tops... Or less...

If terrain was partialy destroyable then it would make game more intense... Atleast some parts like:
- Doors
- Windows
- Some walls
- objects (computer, monitor, chair...)
- vehicles (most of them)

Remaking maps is long and painfull job but it would allow remaking them and making them better, atleast a reason to redo the map and improve most of things...

Use forum search. This topic has been discussed to death.

If you willing to redo all the maps, and migrate the code to a new engine, please do, and tell us when you are finished. If the result is good enough we will apply it to our repo.

-geever
Title: Re: Damage buildings/wall by rockets and/or explosives
Post by: BPRoberts on July 06, 2012, 05:20:55 am
Can someone actually explain why destructible terrain is impossible? No one's ever given a clear explanation of why it's impossible, at best we get excuses or vaguely condescending "it's too technical for you" type responses.

It's constantly stated that the Q2 engine can't handle it, and yet I can boot up Quake 2 right now and blow open a wall in the first level. No one is asking for Minecraft level stuff here where we completely redo a landscape, they just want to blow the wall off a building, something which was doable in a 15 year old version of the engine you guys are using. I haven't gone through the code line by line to see what's different between base ID tech 2 and your enginge, but I would think that if anything it'd be easier now than it was then.

Occasionally someone changes the excuse that it'll cause lag, but I think anyone who has played XCOM will tell you that they'll be happy to sit for a few seconds while that gets sorted out. This sometimes gets tied in with, "it'll break lighting" which didn't even work until a couple months ago anyway and is still finicky. If this is really the case why is an actual gameplay feature getting passed on for the sake of a minor graphical detail?

More recently it's starting to shift towards, we can do it but we'd need to make some new models for exploded walls and/or redo the maps? If it's the art, why do you guys need a half blown up wall to begin with? Just let it be a hole, little art assets like that are things that you can add down the road once the actual gameplay features are done. If the maps are the actual problem I'll fire up the ol' map editor tonight and start poking at them. It'll be time consuming and a pain in the ass, but it's a low skill job that can easily be passed off to the community and taken care of.
Title: Re: Damage buildings/wall by rockets and/or explosives
Post by: Jon_dArc on July 06, 2012, 06:37:04 am
Can someone actually explain why destructible terrain is impossible? No one's ever given a clear explanation of why it's impossible, at best we get excuses or vaguely condescending "it's too technical for you" type responses.

It's constantly stated that the Q2 engine can't handle it, and yet I can boot up Quake 2 right now and blow open a wall in the first level.
I'm not sure there really is a useful explanation other than "it's too technical for you", in no small part probably because it's also too technical for the devs. Destructible terrain is, you may notice, pretty unusual as a feature (and Quake 2 certainly does not feature it—the occasional destructible entity gussied up to look like terrain is a much simpler beast entirely), and I wouldn't expect the devs to have done anything in the area even if they were all employed in the gaming industry (which I have no reason to believe they are).

This isn't to say that it's deep, unknowable magic, but apparently someone did in fact do the hard work of researching to see if implementing it was feasible, and came back with the answer "no". They don't seem to be around anymore, so assuming the devs still trust that person's judgement redoing that research just to give you a better answer doesn't seem entirely reasonable.

~J
Title: Re: Damage buildings/wall by rockets and/or explosives
Post by: geever on July 06, 2012, 07:53:45 am
I know about two problems:
* lightning: The game mostly uses static lights and shadows, which are computed in map compiling time. By destroying the wall in game would the shadow would remain which is awful....
* pathfinding: Destroying objects may open new paths which are probably more optimal in some cases. Pathfinding maps are also compiled into the map (because it is a resource intensive task)

-geever
Title: Re: Damage buildings/wall by rockets and/or explosives
Post by: H-Hour on July 06, 2012, 11:12:53 am
BPRoberts: First, descructible terrain is not impossible, but implementing it would require a nearly complete rewrite of the 3D engine. This was the conclusion of Arisian, who investigated the matter a couple years ago and began working towards our implementation of dynamic lighting (a key step on the road).

However, even if the development team felt that destructible terrain was a key design goal -- none of us do -- it is a unique problem. Handling the generation and then modification of 3D terrain requires extraordinarily complex math. The people who do this stuff commercially are specialists, and the people who do this stuff for free can be counted on one hand (LordHavoc, the Ogre3D people?). We don't have anyone on the team with those capabilities.

The different explanations ("excuses" as you call them) point to different aspects of the problem and typically address why different proposed "solutions" won't work.

1. Q2 supports destruction: Yes, and UFO:AI supports the same destructable objects system used in Q2 (func_breakables). This can not be extended to all of the game geometry or even a large portion of it because the destructable objects are not handled efficiently enough for decent performance. This is not a matter of waiting a few seconds, but even with one or two dozen func_breakables can turn into a 30-45 second pause.

2. Who cares if it breaks lighting?: Lighting is not a minor graphical detail. I can't argue this point, you would just have to see it for yourself. Nothing looks more confusing to the eye than lighting that doesn't behave properly. Lighting is the foundation of visualizing 3D objects.

3. Just create new simple maps if needed: Our active mapping team is named ShipIt. He is the only active mapper on the project who has produced a map in the last year. This idea that we have mapping or modelling talent waiting for orders on what to make next is false. There is no community of people waiting to do time consuming, pain-in-the-ass jobs.
Title: Re: Damage buildings/wall by rockets and/or explosives
Post by: Sandro on July 08, 2012, 07:49:42 pm
Guess I should clarify things a bit. Problem is, the idTech2 engine is based on the concept that all geometry is rigid. To the point that characters ("actors" in the idTech lingo) are actually represented by axis-aligned boxes; only renderer cares about actually presenting humanoid (or not) shapes of them.

And that is how it is handled in all game subsystems -- visibility, physics, pathfinding, etc...

So, with this engine you can move stuff around, rotate, make it appear or disappear (that's how func_breakable works), but you cannot have deformable surfaces without a complete rewrite of the engine. The only easy solution could be making some sort of cheap breakables.
Title: Re: Damage buildings/wall by rockets and/or explosives
Post by: H-Hour on July 08, 2012, 10:23:21 pm
And that is how it is handled in all game subsystems -- visibility, physics, pathfinding, etc...

So visibility checks the box, not the actual alien model? Is it the same for projectile collision?
Title: Re: Damage buildings/wall by rockets and/or explosives
Post by: Sandro on July 09, 2012, 12:15:00 am
Yes and yes.
Title: Re: Damage buildings/wall by rockets and/or explosives
Post by: Triaxx2 on July 09, 2012, 03:28:43 pm
Could it be possible to have them function as states, like doors, with the explosions changing the states?
Title: Re: Damage buildings/wall by rockets and/or explosives
Post by: H-Hour on July 09, 2012, 10:06:22 pm
Doors, like exploding areas, are limited. Too many will cause serious lag, especially since the pathfinding has to update every time the state is changed.