Vis_Leafgroup....a understanding

[Desert Eagle]

First off I would like to thank The Storm for the picture below I am going to use.



I understand if player standing in red area, they will not be able to see the areas in blue, but that the engine still draws them.

Is there a good gain of FPS with using vis_leafgroups?

|RR| Desert Eagle
www.ravensraiders.net

[jv_map]

I understand if player standing in red area, they will not be able to see the areas in blue, but that the engine still draws them.

Vice versa .

Is there a good gain of FPS with using vis_leafgroups?

Yes, FPS gain can be spectacular, but so can be your vis compile time. Also, you risk the introduction of visibility glitches. You need to be very careful with vis_leafgroups, as they allow very direct control on how the game renders your map.

[Desert Eagle]

Once again thanks JV.

Since the compiler ingores detail brushes, I am assuming a good use of vis_leafgroups should not increase complie time to much if they are surrounding areas of detail brushes.

Also maybe I will be the fisrt to use two cpus (not pcs) to compile a map...building a new pc that will be using two AMD Thunderbird 2.0Ghz processors and 2048 ram. (tired of renting game server, so building one)

[jv_map]

Since the compiler ingores detail brushes, I am assuming a good use of vis_leafgroups should not increase complie time to much if they are surrounding areas of detail brushes.

This is not the right way to do it. I assume you're planning to make all brushes detail? In that case just compile with a -fast vis instead, it will save you a lot of work - especially if you want to reconsider later. Vis_leafgroups will still work with a -fast vis.

Also keep in mind every leafgroup you make counts for one additional vis leafnode, which will generally cause a lot of splits in the vis tree. If placed badly, every leafnode entity could generate about 20 new portals , which is very bad for your compile time. Although, for a -fast vis it doesn't really matter.

[Desert Eagle]

No only about 40% of the brushes in the area I want to use the leafgroups are details.

Thats why I want to use te leafgroups to help breakup that area. For instance in the above picture I do not want the farthest "blue" squares to see the red square and vice-verse.

[TheStorm]

First off I would like to thank The Storm for the picture below I am going to use.

I understand if player standing in red area, they will not be able to see the areas in blue, but that the engine still draws them.

Is there a good gain of FPS with using vis_leafgroups?

|RR| Desert Eagle
www.ravensraiders.net

When the player are in the red area he will not be able to see the areas in blue!! and that's because the engine will not draw them (notice the difference from you sentence above) Remember only brushes and models that are completly surrounded by the vis_leaf brush will not be drawn.

Vis_leafgroups work with fast vis, if you do regular vis they will add to your vis data. I think that they can help a map but I don't think making a map with only detail and vis_leaf is an good idea. Look at the berlin tow map that came with "spear SDK". They have only used detail brushes a leafgroups in that map.....but I don't think that map have any good FPS (g

[Desert Eagle]

My whole map is not detail brushes. Just a large complex ship hull is. I wanted the ship to very realistic, and to enusre proper fit, and not losing faces during complie I had to make it detail. The problem is when on board ship, the game engine can see the entire map...which in turn lowers fps. (its the worst on map fps is around 27, and even though the human eye can not see better than 25 fps, 27 is not good enough for me)

So vis_leafgroup will come in very handy. I have read every forum thread on vis, hint, vis_leafgroup on TMT, .map and several other dozen forums.

You have done a very good job on showing how they Work The Storm, and your picture above made it clear.

Yes the Berlin map is a bad example of all detail brushes and leafgroups.
My visdata is still under the 2MB max and I have decide not to worry about compling time.

In this picture you see the fps at 17.5 Using Vis and Vis_groups has now increased it to 45 fps

[Gen Cobra]

I am in the middle of setting up a vis leaf group. Does anyone know anything at all in addition to what has been stated here? I have set the group to help fps. I did it in a cheap way by using high walls to my advantage. I figure it is a good way to learn about what the player should see and what he can't.

[Desert Eagle]

I used them in my large ship to keep other decks of the ship from being drawn while player on board. For example if they were in the botom of the cargo hold of the ship, the two decks and the main deck above them were not drawn by their pcs. By doing so I managed to increase the fps on board the ship alot.

Another good place is to use them inside of buildings, that players can not see into until they enter them.

The best things about Vis_Leafgroups they can target other ones. So if used properly can "hide" alot of the map from players. I had also had the advantage of a night map and some minor fog to help in covering up the Vis_Leafgroups.

Do not get them to close together when they target each other, or in the blink of a eye from nowhere everything shows up. When this happens it looks kinda of crappy. It happened on my map. One building shows up when player is almost entering, and it does not look good or realistic.