Limitations of hammer? map ideas possible/feasible?
Hi everyone, I should start this post by saying I am still a very novice map maker, but I haven't really found a lot discussing a few ideas I've had floating around and would appriciate some sort of discussion or adivce on a few things. The main thing I'm worried about is that some of these ideas may be far too difficult or impossible to create in hammer, running into limitations of the portal 2 engine. If anyone could link to a good site or wiki detailing some of these, I would really appriciate it. Ones I know of from various places are things like the max map size, brushes are limited, but other than a few basic ones I can't find much about what is actually possible to do.
First question on map size limitations, does having instances allow for larger maps or does it still fall into the same max map size hammer allows? As in go in a airlock and prevent view/loading of other section?
Second, what kind of limitations are there with plant life and outdoor type settings? Does the use of a skybox type system allow for lots of vegitation or jungle type maps?
Third, can water/acid be manipulated by objects and or scripts in portal. Can there be flowing water? Or even lowering/raising of water levels?
The main reason I ask these questions is i'd like to have a map that is a hybrid of outdoors settings/testing facilities. My favorite maps are the ones with overgrowth and aged look. What I want to do if it is possible is create a map that is partially outside either in a jungle type setting/forest that either you have to find panels hidden around in planet life etc or have a transition between broken down test rooms that has you fly through a forest by faith plates. My main concerns on having very heavy vegitation are, limits of brushes/objects hammer allows, lack of variety of plant life, having a level that can run well with decent fps for all.
I am obviously just trying to work on my mapping basics as of now, following guides posted all online and reading/studying as much as I can. As without a few practice maps and getting a grasp of hammer, nothing is possible. I love the power of hammer and i have a few pizzle ideas ive been sketching out with things i know hammer is able to, but they will be used in what i hope are unique manipulations and combintions creating new types of puzzles never seen.
I really like how there are so many new types of concept/puzzles I've come across on this site. One being the manipulation of gravity on different plane I observed on The Core mod. I think of Mc Escher craziness type rooms being possible with these types of manipulating. I'm curious if gravity like this can be in motion on say, spinning cylinders that the player or objects can be on, or if they can be activated/deactivated by player interactions/triggers? This is just one example of a map(or mod in this case) that brought something new to the game of portal, another being the map that had fires that could be put out with water bubbles floating on air. These are new concepts that really expand the puzzle making potential of the game, something I'd like to do eventually. Whether it is combining others new conecepts in unique ways/expanding or creating my own unique ones, I love how we can make this game do things that valve didn't even think to do in their campaigns.
Thanks for taking the time to read, I've just had a lot on my mind thinking and learning about map making. I look forward to any kind of advice or discussion on the matter. 
-Stephen
yeah, instances doesnt help. When you compile its the same as if it would not be an instance.
Not sure what you mean about the skybox thingy. But I do believe you can have lots and lots of vegetation. If you run into a problem I think you can have much more prop_static plants (dont move) than prop_dynamic (sways in the wind)
With a scrolling texture, yes.
Yes.
"I hear voices. But I ignore them and I just carry on killing."
Thanks for the quick reply! I loved your map 12 angry tests, my pc is actually in the process of uploading my blind play through as I type. A lot of the idea of "outdoor" testing came from your initial tropical view of the intro scene. I thought that having a map in a setting like so would be very unique and fun. I'll be experimenting with plant life a bunch this week, hopefully I can make a believable outdoor type setting.
Again thank you!
To make something clear, gravity changes are very hacky and frankly a nightmare to set-up. Also, once they're set up, you can't change the gravity in that room whatsoever. It's all fake; it's basically a portal that teleports you to a room that's facing another direction (so it FEELS like a gravity change, it really isn't).
I wouldn't mess around with that until you're very very familiar with Hammer.
Almost anything is possible in source, although it might be a little bit of trouble to execute.
Running water can be achieved with animated or scrolling textures (as mentioned above). Water effects can be created from particle effects (sounds really help too).
The size of a map is limited, however that is the whole reason for transitioning maps to the next. It makes it fit inside the Hammer's grid bounds and increases performance. If you could make a map the whole size of the hammer grid that would be outrageous (though not infeasible).
Plant models are available in portal 2, but you can always download custom models if you find that there isn't a model you particularly want. I know for a fact that there would be plenty of maps which would have a 'jungle theme' which is made in source.
E.g. http://www.gamebanana.com/css/maps/4701 (make sure you ask permission first before taking any models or textures).
Honestly I think gravity changing puzzles are a bit overrated, most probably causing more trouble than you want.
If you want to learn how to map outdoor areas, i suggest that you look at some tutorials for halflife 2 mapping, there are plenty out there. also, gravity changes are cool, but bloody glitchy and somewhat gimmicky, bug if you canake them work well, good on you. You cam do most anything you want in source, but it can be a bugger to get working at times.
I think in terms of boolean variables. Generally, it makes things easier.