Explosion Updates

So here's what I've been working on recently. Currently in the process of reworking this gas station scene and here's where I'm at with the explosion. It still needs a lot of work but thought I'd do a quick update. 

First issue is the trails of debris from the explosion. I don't like the use of sprites so I am thinking about using ribbon data instead. I just couldn't get the trails to not be so popcorny. I also need to re time the lighting and work some more on the shape of the explosion. It doesn't look right as it fades when you can see stray sprites. 

This is something that I've been reworking recently, just tweaking a bit to make it ready for when I redo my portfolio. Though this was also a test of render styles. I was looking back and I didn't like all the black emptiness so I was trying out how fog affects the feel of it. I like it, but I'll probably need to redo the whole scene to make it portfolio ready.

Progress

Just a quick update as I've been reworking one of my old projects and I thought it'd be interesting to compare the original and this new one I'm currently working on. 

The one on the left is the original and the one on the right is the new one. Admittedly the new one still isn't quite there yet but it's just nice to see the improvement for myself. Though I'm struggling to mesh the fire and the smoke together in a coherent manner. I like the fire, it's got a nice fluidity to it and it has a lot of variation. And I like the smoke, the flow maps give a a good sense of internal motion. But I don't like how they work together, they look too much like separate entities.  

Flame On

So I've been practising my work with fire in both simulations and realtime work. As I'm currently redoing the gas station scene from scratch I thought that I'd start it properly by going back to making some fluid sims for tests. This was a good opportunity to get some more practice using Maya Fluids. I feel like I'm getting more used to it now, I'm definitely more confident in my ability to use it to create flipbooks and textures. 

I made other sims to make into flipbooks as well as use them to generate the textures below.

Instead of creating flipbooks I decided to have a go at using UV distortion. Although it's more expensive than just using flipbooks, it provides more variation and thus looks more natural. I also implemented alpha erosion within the material as well as I thought it was a more realistic approach to fire, although it bumps up the cost of the material. 

Although I like this approach, as it gives a good natural result, I need to work on the alpha erosion as you can see there's some popping. I don't know whether I need to rework the setup or switch back to usual alpha fading. I'll try to stick to alpha erosion as I don't like how the normal alpha fades in and out so uniformly because it doesn't look realistic enough. And yes, I think I may have overdone the bloom :) 

RnD and Sparks

So recently I've been doing a bit of RnD whilst finishing off the sparks project. I've been trying to get better acquainted with Maya Fluid Effects. I've used FumeFX before so I have experience with fluid simulations but I've been trying to get used to Maya as I've found it less taxing on my computer and quicker to iterate on. So this is just a quick simulation to get better with it, but I want to get better with it so that I can actually use it for RnD for FX for creating better and more realistic flipbooks. 

Another thing I was working on is using distortion for shockwaves in my effects. It's one of those things that I've found really lacking in my work, I didn't really know a good method for it. From left to right; using a black and white texture in the distortion, using a normal map in the distortion, using a panning texture with a sphere mesh, using a panning texture on a ring mesh. I feel that the one on the far left, using just a black and white texture in the distortion, is the strongest visual impact. A method I will employ in future work, especially with effects that have a strong impact or shockwave like explosions.

This is the final render for the downed wire project I was working on. I created the animation for the wire in Maya, though it's not a procedural animation so it might not be the most effective approach. I then attached the emitter and animated it in matinee. 

What's Keeping Me Busy

So it's been a while I guess, but now that uni's done I'm free to work for myself again. Obviously I've not been working all that hard, but having not seen my family in almost six months means I've had a lot to do since being back. 

But it's nice to have the freedom back again. I took a couple of hours the other day to just work on some idea generation. Admittedly, I still need to work on it but it's given some good starts for projects once I finish the projects for my demo reel. 

Speaking of, here's some of my progress on a couple of projects. First is the base for a downed wire. This is pretty much the particle system done, now I just need to make a wire and make an animation for it and then I can attach the emitter to it.

And second is a simple incense burner. This is practically finished I just need to render it out properly as this was done at a low res for speed and ease. But this was a nice project to work on to learn the basics of flow maps and how to create and implement them. Now this is something that I can take over into other projects as well.

As for what I'm working on now, I'm completely redoing the gas station explosion scene. I'd been working on it for too long and I was feeling like it was going nowhere. So I decided to completely redo it and took this as an opportunity to get myself more comfortable with using fluid sims.

Depth Bias Alpha and Plans

So now that I've effectively finished with uni I can finally take the time to get back into doing what I love. So I took some time to sit down and try and learn how to make my own depth bias alpha as it's something I end up using a lot in my FX and it's just so expensive. The base of this is from a section in Bill Kladis' recent tutorial. But I modified it to work directly in cascade as well as using some of the techniques from Uncharted 3's excellent FX presentation.

Above is just a simple test emitter with a simple circle sprite. As you can see where it intersects with the geometry it creates a hard edge.

Using a simple scene depth and pixel depth equation I was able to smooth out the edge. But I linked the control with a dynamic parameter so that I may control the softness of the intersection  directly in cascade.

Then using the idea behind the fire techniques in Uncharted 3 I was able to run a couple of gradients through the scene depth before it had the pixel depth subtracted from it. This breaks up the straight edge of the intersection to make it more natural and varied. This is great for effects such as fire, which is what I ended up trying it with. Again I can control the amount of noise with a power node connected to a dynamic parameter so I can control it on the fly in cascade.

Here you can see the material. It's still not exactly cheap so I have to be wary of how many particles I spawn but considering a normal depth bias alpha node generally pushes my materials above 50 instructions it's certainly much cheaper. And I could make it cheaper still, if it's just a smoke or any normal material that needs it I could remove the gradient stuff.  

And here is how it looks on a really basic fire emitter. But now I've learnt the basics of how it works I can start implementing this in my pipeline and decrease the instruction counts of my materials.

But now that this little experiment is over I should start thinking about what I'll be working on next. Now I've got the time to start working on my show reel properly, and not a rush job in a week for deadlines. I think that I've got a good starting point for one; I might render out my rain shader properly by itself as a break down of the street scene. I think I need to almost start from scratch with the gas station explosion and redo it. I can take this as an opportunity to really get to grips with Maya Fluids and improve on my skills using fluid sims. As for that spell effect, that just needs to go, it's just weak. But I think that if I worked just a bit more on the beam that I could get that to be a really nice effect.

Showreel

00:00-00:36 - Alleyway Environment. I worked on all the environmental FX in the scene including all particle emitters and rain shader in UDK. All assets made by me as well.

00:37-01:00 - Gas station explosion. I made all the emitters and textures. Flipbook textures made in Maya using Maya Fluids and After Effects. In UDK.

01:01-01:30 -  Energy beam. I made all textures and emitters. In UDK.