While upgrading versions on DotCam and TK-Master’s Ocean plugin I realized while there are some underwater camera effects in the new version, there isn’t any fog effect, and having previously run into the limitation of a single Exponential Height Fog actor per level in UE4, I realized I would need to buckle down and write a fog shader myself. Not hard, of course, but there are a couple of tricks that should save time and hair pulling.

First, let’s see how the current underwater shader effect in the example level looks:

Not bad – the animated 4-Way Chaos setup combined with the wavy normal map does an admiral job at simulating the effect of looking through clear water.

But what if your ocean has a high amount of plankton, or other debris?

Something like the above is a bit more suited.

To replicate this, create a new material and set it to be a Post Process type.

Then recreate this node layout:

The code for the custom node (ExponentialDepthFog, in the image) is very simple:

// Get the distance from scene depth
float dist = length(pixelDist);
float fogFactor = 0;

// Compute our fog lerp factor
fogFactor = exp( -pow(dist * fogDensity, 2));
fogFactor = saturate(1 - fogFactor);

// Lerp between fog and scene color.
return lerp(sceneColor, fogColor, fogFactor );

Once you’ve created the material, add it to your underwater PostProcessVolume under the blendables section.

So my Razer Hydra arrived and I spent a little bit of time trying to set it up via Getnamo’s Razer Hydra plugin for UE4, which is awesome! I was able to quickly get it passing values into the game.

The problem lies in transforming the controller position from base-station-relative space to the game’s world space (or the character’s local/component space, even).

After toying with it for a bit I could get it to almost work, but for now I’m setting that aside until Mrob76u, author of the Ultima Underworld VR Remake can share his setup.

I got back to working on the base gameplay and made some decent progress.

Progress towards the gameplay video:

• Health, damage, and death for the rats
• Crushing/impact damage for the rats so that the player jumping onto them causes damage
• Rats spawn a rat corpse item that the player can pickup (and eat), on death
• Rats take damage from fire
• Fixed a couple of misc. bugs
• Fixed throwing force so that throwing a torch is satisfying

Here’s the list of remaining stuff to do from last time, some of which I’ll hopefully get to tonight.

• Kick attack for the player
• Two-handed pickup animation and code setup for the player (to throw barrels)
• Creating a “flee” state for the AI, so that rats that have been attacking run away faster than the normal walk speed
• Setting up flee mode so that cowardly/non-aggressive rats will skitter away when the player nears
• Blood effects on damage for the rat attacks, and also when the rats are damaged
• Hunger/starvation code and an eating AI for the rats.

Since the weekend I’ve been making rapid progress on the rat enemy and its AI behavior.

Here’s what was done yesterday:

• Implemented rat attack routines
• Set up jump and lunge forward functionality for attack
• Jump bite animation during attack
• Cowardice and aggression system – some rats will not attack, or will attack and run away
• Dealing damage reduces aggression (taking damage will increase cowardice, but that’s not in yet) so that rats do surprise attacks and skitter away

Progress is steady towards the state I’d like it in for the gameplay demonstration video, but there’s still a lot to do, including:

• Health, damage, and death for the rats
• Kick attack for the player
• Two-handed pickup animation and code setup for the player (to throw barrels)
• Creating a “flee” state for the AI, so that rats that have been attacking run away faster than the normal walk speed
• Setting up flee mode so that cowardly/non-aggressive rats will skitter away when the player nears
• Blood effects on damage for the rat attacks, and also when the rats are damaged
• Crushing/impact damage for the rats so that the player jumping onto them causes damage
• Hunger/starvation code and an eating AI for the rats.

Once that list is done, I’ll be moving on to work on expanding the level, adding more items, and some traps. The level and traps work will complete the features I want to have for the video I plan to make.

I estimate 1-3 weeks for those features, depending on setbacks or delays.

As an aside, my Razer Hydra arrived from eBay today, so I’ll be jumping into making that work in the game at some point soon.

One gameplay mechanic (which will be expanded more as time goes on, into a generic system for flammable items) currently in Dungeon Survival is a destructible barrel ‘filled with’ (spawns) oil.

This uses UE4‘s built in NVIDIA APEX Destruction.

As any UE4 dev that has played around with destructibles will know, the actual destruction event doesn’t network “automatically” in any way – even if damage or collision events are.

That presents a problem.

What happens currently – you can enable movement replication on the destructible actor. This works well (probably not as well over the network), all the way up until the thing breaks, at which point the oil spill is placed in a totally different spot on the client and server.

Now I should point out that technically, my destructible barrel isn’t using the destruction system the “right way”. For something like a barrel which you want to accumulate damage and break, there is a built in impact system. Unfortunately, I was not able to tune that to act how I wanted – a predictable amount of hits to fracture the barrel.

So right now instead the barrel is set to generate hit events. I check to see how strong the hit was, and if it’s over a certain threshold, I apply some damage to the barrel, which is set to fracture if a certain amount of accumulated damage is ever applied.

Because of this particular setup, the way to network it is quite clear – handle not only the damage, but also the fracture event and spawning the oil slick on the server, replicated to the client.

In this fashion the server will determine where exactly the spill is placed, even if the client’s destructible fractured in a slightly different position.

I’ll be updating this post later with screenshots demonstrating the problem, though for now fixing it is a Backlogged task.

Since I’m guessing this won’t last, I took a screenshot.

Thank you r/oculus and user WeAreVR-Nn23!

I did not expect this!

Check it out – Dungeon Survival on IndieDB.

It’s fairly barebones, but I’ve also uploaded three hi-res (6720×4630) screenshots to the IndieDB page.

Here’s a taste: 

A horrible way to die – burning up in oil while lying on broken shards of wood.

Just wanted to quickly point out that I’ve added some tools for keeping up to date with the progress of the game. 

On the right hand sidebar you’ll see both a Follow This Blog for WordPress users, and a Follow by Email option for those that aren’t signed in. 

Trello board – Added a list of to-do for Oculus Rift support