Now that's something to have some fun: Primotechnology published instructions on how to play Halflife2 Singleplayer with the portal gun enabled ingame. Hopefully someone will figure out a way to do multiplayer games with the portal gun.
The steps from their site:
- First off, backup up your entire Portal directory in a safe place. It’s the folder marked ‘portal’ in ..\Steam\steamapps\(your_username)\. We, nor Valve, take any responsibility in the unlikely event of you hosing your game files. Worse comes to worse though, you could always just redownload.
- Next, download and install, if you haven’t already, GCFScape. This handy program will allow you to access the cached game files for any Source-powered game, in addition to several other Steam games you may have downloaded.
- Once that’s done, browse to the directory ..\Steam\steamapps\. There, you’ll see all the available GCF archives. We’ll start with Half-Life 2.
- Open the GCF marked ‘half-life 2 content.gcf’ You’ll see a directory tree in the left pane. Click the box to the left of the folder marked ‘hl2’ to see the directory listing contained within it. Then, right-click ‘maps,’ select ‘Extract’ and extract the entire folder into the directory \Steam\steamapps\the_great_bundini\portal\portal. This will merge it with the existing Portal map folder.
- Do the same with the ’scenes’ folder
- Fire up Steam and run Portal. When it’s done doing its thing, open up the developer console with ‘~’ (you may need to enable it under your keyboard options).
- At the console, type ‘maps *’ to list all the available maps. Now that you’ve imported the Half-Life 2 maps, this will be a fairly lengthy list and some of the names, like citadel and canals, should seem familiar.
- Type ‘map’ and then the map name to open that map. For instance, ‘map d1_canals_01’
- When the map is done loading, pull up the console again and enable cheats by entering ‘sv_cheats 1’
- o give yourself all weapons, including the portal gun, enter ‘impulse 101’
- Depending on how far you got in Portal, you may need to upgrade the portal gun to fire both portals. Enter ‘upgrade_portalgun’ to do so
- Have phun!Go lay waste to some alien scum with the power of portals!