how big is too big?

[polypod]

i am done with my log cabin test map and about to start a larger/more complex map of a corporation headquarters, with parking lots and multiple levels, etc..
i noticed in HL2 there was constant loading every few buildings.. were each of these seperate maps? can't i make a really big map as long i pay attention to render requirements at any one time?

 

[Pi Mu Rho]

You could have a map that fills the maximum limits, superbly built so that each area occludes another and the framerate never drops below 100. However, all that visibility and lighting data would put the map size somewhere in the hundreds of Mb.

 

[bliink]

However, all that visibility and lighting data would put the map size somewhere in the hundreds of Mb.

and dont forget, all those Mb need to go into RAM.. so it might end up imparing the framerate anyway

 

[polypod]

i was imagining walking through the parking lot and making it so the main building was not yet visible and when it was, the parking lot would no longer be..(by like having signs on the fence or something so i could make entire areas appear/disappear without being noticed)
doesn't the RAM wait til i make something 'visible' to load areas?
if i'm using the same textures, what makes it bigger? can't i keep the engine from seeing any more then it would in a HL2 level?
and are you saying that each 'loading' session in HL2 was a different map? Or is there a way to break it up easily?
okay after re-reading the post you're saying the .bsp file will still have to store all the info for every bit of the map, so i can see your point.. are there any tips for dealing with this? does lighting data take less .bsp space then textures by far?
Seems like a well made, smooth running map might be worth downloading a large .bsp file anyways..:stare:

 

[The Dark Elf]

i was imagining walking through the parking lot and making it so the main building was not yet visible and when it was, the parking lot would no longer be..(by like having signs on the fence or something so i could make entire areas appear/disappear without being noticed)
doesn't the RAM wait til i make something 'visible' to load areas?
if i'm using the same textures, what makes it bigger? can't i keep the engine from seeing any more then it would in a HL2 level?
and are you saying that each 'loading' session in HL2 was a different map? Or is there a way to break it up easily?
okay after re-reading the post you're saying the .bsp file will still have to store all the info for every bit of the map, so i can see your point.. are there any tips for dealing with this? does lighting data take less .bsp space then textures by far?
Seems like a well made, smooth running map might be worth downloading a large .bsp file anyways..:stare:

Each map is loaded entirely into memory. What you can and can't see is still stored in memory, its just not displayed. So using say, areaportals you can keep framerates up, but all the map will still sit there in memory waiting.

Each time HL2 or HL1 loads a new section, its loading a new map (though there's a possibility HL2 has more than one map in some of the bsp's that are completely hidden until accessed the correct way.

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Your only major concern with doing a single map in Source, is the limitations, you've only got so many brushes, and entities you can use in a single map.. Granted, prop_details aren't a problem, since those you can have thousands upon thousands of. But the others are limited. You'll not come up against this in most cases (though possibly the brush limit) but on a very large detailed map, you'll likely hit the limits at some point.

Textures you really really really don't want to include with the bsp, make them a separate download.

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Definately make use of Areaportals, you can turn off entire area's then, eg: when outside the building, have the interior completely switched off. Then make a buffer zone between the exterior and interiors. For example.. To enter the building, have the player enter a smaller area that exists between the exterior and interior portals.That will mean you don't turn on the complex interiors while the exteriors are still visible. Which could slow things to a crawl for a few moments. Using the buffer zone will let you turn off the exterior before the interior is switched on. So the engine doesn't at any time have to deal with both at once.

Course the above assumes you'll only make two types of portal like that. Personally I'd have the exterior built in a way that lets you switch off a number of area's in that, the buffer zone, and then split the interior up into portals, perhaps per floor, even per room.

Also bare in mind the bigger the map the longer it'll take to load, so if you do one that big, make sure it is very good or people will get bored of the load times.

If your doing this for single player. I'd really recommend you go with level transitions and split the map up into much smaller sections.

For MP, its not so easy, you can still split the map up, but there's a few tricks required to make it plausable for when a new level change is triggered (ensure all players are within a certain area before it changes levels perhaps)

 

[polypod]

very informative thank you everyone..

so can i build my whole map at once and break it up later easily? maybe put each future 'map' on a different layer?