Rockin' some Rocks

Just a rockwall done for practice one sunday afternoon. Trying out some new techniques, as well as Marmoset Toolbag 2.

Happy new years!

A simple asset, but a lot of technical hurdles...

I decided to practice some sci-fi and found this neat concept by Jeremy Love.

Very simple asset, but when I brought it into UDK it ended up looking like this:

Ugh, awful.


My problem is that my normal map is mirrored, which means that half of the UV shells are flipped which cause problems with how the normals are calculated in the engine. 



Look at all that red. That's a bad sign all right. So after some research I came up with this solution.

First of all you need to fix your UV's. UDK hates mirrored UV's so I flipped the red shells so they are blue and nicely correspond to their geometry again. The problem of course is that they no longer line up with the texture any more, but there's a solution to it. 

In UDK you can change the way that textures tile in the Texture Properties. The default is Wrap which is the mode we're all used to, but there's also Mirror and Clamp. Mirror is the one we're interested in because it does this:





Excellent! This means that if we lay out or UV’s this way they will match the mirroring:



But it’s not that simple, because when you mirror the normal map horizontally you end up flipping the X axis (red channel) which causes mirrored  lighting.  But with a little bit of material editor magic we can fix that.
We can flip the red channel by multiplying the normal map with a float3 with the values -1,1,1, but we want that to only apply to the mirrored UV’s. This is also fairly simple. All we have to do is to lerp the two normal maps with a checker pattern with its UV tiling set to 0.5. This will make it match up to the alternating mirroring and mask out the x-flipped normals from where we don’t need them. But again it’s not that simple, because when you mirror the normal map horizontally you end up flipping the X axis (red channel) which causes mirrored  lighting.  But with a little bit of material editor magic we can fix that. We can flip the red channel by multiplying the normal map with a float3 with the values -1,1,1, but we want that to only apply to the mirrored UV’s. This is also fairly simple. All we have to do is to lerp the two normal maps with a checker pattern with its UV tiling set to 0.5. This will make it match up to the alternating mirroring and mask out the x-flipped normals from where we don’t need them.



And the results?



Perfectly mirrored normals! No seams, huzzah! :D

Hope this is helpful to y’all.

The Apex Observatory is finally finished!

Finally finished this gosh darn thang. Still lots of room for improvement and things I want to add and tweak, but it's time to move on.

The scene was designed with a point and click adventure in mind, so this is the angle it would appear in game. I laid it out in a way so that they player would always be visible. The general idea is that you take the lift up there and try to convince the hermit astronomer who lives up here to help you.

Here's the hero prop himself, the telescope. Once I got a cubemap of this environment baked down it fit in the scene much much better. There are still some stylistic clashes that I want to touch up on, like the wood, but that will be later.

Here are some simple sketches I did to work out some of the designs and layout.

Now let's talk technical art! :D

The whole scene uses five materials. One unique material for the telescope, and 4 modular materials that are instanced across the rest of the assets. I have one basic diffuse/normal/spec material, one metallic material, one window material and one foliage material.

This is the basic material, and as the name implies it's fairly basic. It has two parameters to control the specular strength and the glossiness of the asset as I find those always require a lot of tweaking. The Material Function is a simple setup to control the U and V tiling separately and I made it into a function because I found myself using it a lot over different materials.

The metal material is just the basic material with a cubemap added on top of it. Instead of just multiplying the cubemap right on top of the diffuse I use Fresnel as a mask into a Lerp node so the reflections are stronger at a glancing angle, which mimics how reflections work in real life. I also have a Reflectivity parameter that simply fades it out for a more subtle look.

The telescope material is similar to the metal material, but with some added effects for a spesific look. Looking around for tips on metal materials I found what some called a "car paint" effect, and i liked the extra boost it gave to the highlights. I'm also adding the cubemap and car paint effect to the emissive. The metal material originally had this as well, but I didn't like the look of it on the other assets.

For the foliage I had to rebuild the lighting because I was using custom vertex normals on the alpha planes. I also added a parameter to control the diffuse brighness to lighten the shadowed areas.The reason I did this is because I changed the Lightmass settings to give a much brighter and colorful look, but the foliage is dynamic and don't recieve the same indirect lighting. Some fine tuning is needed since the leaves turned out extremely bright in some shots.
It also has a simple sine wave in the WorldPositionOffset to give it the look of rustling in the wind. Vertex color is used to mask the weight of the wind for a less uniform look. I decided to go for a simple setup like this rather than deal with WindDirection actors because the scene was so small and only had a few assets it effected.

The first couple of attempts at the tree didn't turn out good at all so I took a close look at how the Airbørn team did their wonderful foliage, and I discovered that they just had a ton of alpha planes scattered on a mesh with a tiling texture. Super efficient and gives really nice looking results. Using a script I was able to mash this together in 5 minutes. The central mesh also helps deal with overdraw.

Now to round this off here are some things I learned from doing this:

• Don't overthink stuff. The simplest solution is often better and will save you a lot of time. The first iteration of this environment fell apart because I was getting too elaborate with the modularity and materials, which resulted in a slow and unsatisfying workflow.
• Have a plan. The biggest mistake I did was to jump into this without a clear piece of concept art and an asset breakdown/list. Since I winged a lot of the designs as I went along most of the stuff in this scene went through several iterations before I got a result that worked out. This was a big waste of time and I could have finished in half the time if I had spent more time planning ahead of time.
• Use lots and lots of material instances. In the beginning I kinda rushed through the process and had a unique material for every asset because I didn't really care about performance. But as soon as I cleaned up my scene and instantiated my materials it became immensely easier to do tweaks for each asset, and having them all draw from the same parent made updating and adding to them much faster.
• Use more scripts. This is something I already know and need to work on, but it bears repeating. Using scripts and shortcuts for even simple stuff speeds things up immensely. If something usually takes 3 steps and you can reduce it down to 2 you've just sped yourself up by 33%! I still prefer doing some things by hand. Automation can only take you so far, there is no good make art button.
• Take breaks. There were parts where I was so sick of this environment and strongly considered scrapping it because I felt it wasn't going anywhere good. This was usually after working a whole week straight on it with no breaks. After stepping away from it fora few days and doing something different like the Art Jam I was able to return to it with new vigor. But aside from big breaks like that taking small ones during the day are important too. I started experimenting with the pomodoro technique which means I have a timer running and every 25 minutes I'll take a quick 5 minute break and step away from the PC. I'll go outside, do the dishes, make a cup of tea. Anything that's not in front of the computer. When I return I've reset my mind and work more efficiently because it eliminates the habit of getting caught up in small details and gives you a chance to think about the problem at hand. And my room has never been tidier. :p It's probably not for everyone, but I recommend everyone give it or at least some variant of it a go.

And in general I learned a TON of technical stuff about UDK and game engines in general, lots of material tricks, some neat sculpting workflows, NDo2 and DDo, and how awesome the Polycount Google hangouts are for productivity and learning. Thanks guys!

Polycount art jam presents: Porco Rosso!

Polycount has this art jam thread going on where they rotate through themes every week. This week's theme was Studio Ghibli, so I did a bust of the dreaded flying pig Porco Rosso!

Blocked everything out in zBrush and then brought parts into 3Dcoat and Maya to tighten them up a bit. Then I did a nice soft polypaint pass and brough some screengrabs into photoshop for some color adjustment goodness. Fun times!

Just playing with Maya Vector.

Just for fun.

UDK Fake Thickness Material

Today I made a material that fakes thickness on surfaces that use transparency masking. 

The concept is basically to offset the texture with a Bump Offset node (also known as Parallax), then darkening it with a multiply node, and then adding it underneath the original texture with a Lerp node. It doesn't handle corners that well, so I'm wondering if multiple stacks of Lerp might help with the illusion but I'm worried about the drawcalls. Also, I'm not sure if this is more efficient than just stacking two planes, I'll have to do some testing.

Here is the Material Graph:

More technical art!

I saw a pretty good explanation of a Silent Hill style transition material so I was inspired to try that out myself. The article in question is here: http://dp3dblog.tumblr.com/post/26742825968/thoughts-on-texture-transition-fx
But I did a change to it where I did an Add operation of the rock texture on top of the transition mask to make the glow effect match the rock texture better.

The material is connected to a Matinee that controls the transition parameter, and the Matinee is triggered by a key press through Kismet. T to make the transition, and G to reverse it.

Big ol' backlog of stuff.

All right, been too busy to post lately. Here is a bunch of stuff from the end of the semester:

The ecorche is done, which is the project that has absorbed most of my time this last month. Every muscle and bone has been modeled out, although the proportions are a bit off here and there. 

Creepy Spider dude thing. 3 hour sketch experimenting with alphas.

Urania the greek Muse of Astonomy and Philosophy. A midterm project for my Myth and Symbols class where I had the option to make a piece of art rather than write an essay. Rendered with vRay.

Base for the hair and cloth was done with zSketch.

 Fishman, another quick sketch.

 Experimenting with the Unity engine's Terrain system.

Little toy people

Saw a guy at zBrushcentral who used zBrush to design vinyl toys, so I decided to give that a try.

Rendered this guy in VRay and gave it funky colors in Photoshop.

This is just the zBrush viewport, I might render him later once I find a good way to transfer the polypaint colors.

Big fat update.

I keep forgetting to update this blog, so here is a big pile of what I've been doing lately.

Skeleton is almost done. Just need to finish the feet and skull, and fix some proportions.

Elaborated more on the scar of this guy.

Experimented with some Mental Ray features. Not really noticable in this picture. Details here: http://forums.cgsociety.org/showthread.php?f=87&t=970700&page=1&pp=15

Did a bust of Disney's Jafar.

A shitty arm study.

And experimented with some zBrush alpha features and texturing techniques.

 Which I recorded a video of, gonna start doing this for my sketches from now on.

Hard Surface Final, lowpolied and textured.

This is why I haven't done my sketches the last week. Been compiling my work for GDC.

Pigman

I intended for this to only be a quick one hour mouth study because I have other homework for tomorrow. Instead I ended up spending 3-4 hours on this guys' ugly mug.

And lookit! I recorded a video:

Bone daddy

I wanted to test out 3DCoat's voxel sculpting a bit more so I made a skull. I have a piggy bank that is cast from a medical skull so I used that as reference. It has some anatomical and proportional issues, and the underside is not finished at all, but I was sick of staring at it so I did a quick retopo and threw it into Modo to play with some more rendering stuff.

Modeled in 3DCoat. Rendered in Modo.

Realistic head assignment.

This week in my Organic Modeling 2 class we got an assignment to render a realistic head using a SubSurface Scattering material in mental ray. The head model and texture is a free 3D scan from Infinite3D, but we had to take care of baking the normal map, creating other maps like spec and SSS depth,  adjusting the SSS shader, and finally lighting and rendering the model ourselves.

I'm pretty impressed with the results myself, but I still see room for improvement. At least a lot of the mystery surrounding the mental ray SSS shader has been lifted. :D

All the images are rendered in Mental Ray using Maya. In all the setups I use a single light with an HDRI probe to provide additional ambient light through Final Gather.