How to Create and Manage Visgroups in Source

Following tutorial was written and contributed by Keith Garry

To explain visgrouping let's look at two scenarios first:

One: You have been working on a map for quite some time now. It has many floors, and it has gotten pretty big. You decide you want to create a arch on a wall, but because your blueprints contain so many different lines it's hard to make out what is what.

OR

Two: You have just finished texturing your map and decide it's now time to add lights. To compile your whole map just to check if one area it lit correctly would be ludicrous.

Both of these examples are perfect for visgrouping. Visgrouping allows you to hide groups of your map in order to see things more clearly; select and go to certain areas quickly; or to compile specific areas of your map for testing purposes. Overall they are used to keep your map organized.

Find an area to select.

Select it(Shift + Enter). Press Alt + Enter. Click Edit Groups.

Click New Group.

Select a color and choose a name. Remember to click the box you want your selection to go into. Click Apply.

Additional Notes/Resources:

CrowbarSka:

However, in the second scenario I would personally prefer to use Cordon Tools. With these you can simply drag a box around the section of your map you want to test and then enable the cordon. Everything outside it is ignored (both in Hammer views and when compiling). You can also set the texture that this box will apply in Tools > Options > Cordon texture, so you could use it to make a quick, temporary skybox around a small portion of a large outdoor environment.

Developer ValveSoftware Wiki - Grouping/Visgrouping

Question: How do you tell it to compile the Visgroup only?
Answer: Hammer will compile whatever is 'enabled'. So any visgroups that are turned on will be in the bsp, and any that are turned off will be left out.

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