[Half-Life 2] Incorporating stealth elements

Hi fellow mappers,

so, lately, I’ve been watching lots of Metal Gear Solid let’s plays again, and since my main projekt is stuck anyway due to an issue with Hammer, I thought I’d pick up an idea I had quite some time ago, which was creating a proof-of-concept map for Half-Life² that incorporates some stealth elements into the gameplay. Since I don’t know shit about modding source code, it’d be mapping only.

So I wrote up some ideas and I thought, why not ask around whether anybody’s got more ideas to add to this list. So far I’ve thought of these:

  • using “toolsblocklos” (block line-of-sight) brushes to enable the player to look through windows or past barricades without being spotted by enemies by making the brushes a good bit bigger than the obstacle, making sure the player can be seen while standing but not while sneaking.
  • using game logic to set enemies’ state to “idle” some time after they lost sight of the player (if I recall correctly, npc_combine_s and such fire an output when they lost their enemy).
  • misusing func_tank as security camera by setting their damage to zero and setting their sounds to silent, then parenting a camera model to them. This way, they’ll spot the player and aim the “camera” prop at him (and, via outputs, subsequently alert soldiers) but do no damage.
  • modelling triggers (vertex edit) to emulate the viewcones of cameras (static props), perhaps with added dustmote effect to visualise the line-of-sight. These viewcones would cover most of a hallway, for example, but leave space to evade them.
  • using game logic similar to the Half-Life² battery puzzle to detect the presence of props identified as chaff grenades or jamming devices to allow the player to disable surveillance measures - prompting soldiers to investigate (via ai_goal_assault, clearing rally points) but giving players a time span to pass through an area unseen.

This is what I thought of so far. The list seems pretty good to me, but I feel like I’m missing something, so… anybody got stuff or suggestions to add to this list?



Underhell had a great system where it had global music triggers depending on the level of awareness the npc_combine_s had of the player, leading to an alert, caution and sneaking style in the gameplay.

Mxthe was also smart enough to know that sneaking in first person is a lot tougher because you can’t peak around corners, so he parented projectedtexture flashlights so players could see enemies coming. Most of it would be in-hammer scripting, once a soldier has lost the player you can force him back onto a patrol route.

Hope this helps, I hope to see where you take this project, I’m very interested.