Dune's contest stuff

Started by Dune, February 26, 2013, 03:23:53 AM

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I did one yesterday that I thought to enter after some refinement. This old track crossing a wild stream. Don't look at the title of the file; flooded road was my intention, but it became a bridge.

So now I have thought to give myself a theme to work from. Here's some reference that I hope to replicate, maybe I'll find something else, like a road torn by earthquake. The theme obviously is 'Road Hazards'. I will, time permitting, probably make 2-3, and then choose whichever seems the most photographic.

Off we go.


As you may have noticed, I'm in but actually out (being a NWDA-member). But for anyone wanting to pick up some ideas, here goes....

I decided to pick the flooded road photo as reference. First I took the basic road leveler from my Mountainside Road Pack, but in this case a normally warped simple shape line would have done for the road. The warp seed was hit a few times until I had a nice curve ahead. The soft perlin terrain was stretched a bit, so the road would go across a series of heights and dips, and a flood could go through one of the dips, perpendicular to the road. I hit seed of the perlin a few times until I had a decent dip right in front of me, kind of like in the photo. Then I added another soft edged simple shape of about 30m, used that to deepen the flood area. The road simple shape was used as a basis for a tarmac and lines. Usually I add a color adjust shader between road and terrain shaders to adjust the hardness of the road edges.
An inverted color adjust shader (coming from the road simple shape) was used to blend the surface shader containing a stack of grassy colors and small displacements. Next in line is the road surface shader, blended by the color adjust shader coming from the simple road shape. I wanted to raise the roadsides across the stream a bit so I added a distance shader, which blends a surface shader, in which I displaced the inverted road by 60cm.
I also want to make the road a bit curved up in the middle, so I added a transform shader from the main road simple shape, decrease its X to 0.6 and fed that into a displacement shader (0.2m) in the road line.

For the distance some higher (wooded) hills were needed, so I added another distance shader, plus another perlin, hit seeds a few times and there were some nice hills further across the stream.

Basics done, so then I needed a mask for the front roadsides (grass, herbs). So from the soft road shape I added a color adjust shader, set the gamma to 0.15, the black point to 0.8, and added that and the initial road shape to a merge shader, subtracting the hardened color adjsut shader from the soft normal shape, voila, roadsides. I could thus play a little with the values and get the grasses cover slightly more or less of the road.

Then the water. This is a plane, not a lake, so I can adjust its length/width more easily. Basically I start with a water shader, with a brownish murky color as volume 1 density 0.5, and some small scale waves, and a raised patchiness with decreased size. I then wanted some curly waves kind of perpendicular to the stream, so I took a perlin fractal with decreased whiteness, stretched 3x in Z, hit seed a few times until I had a decent distribution of white stripes across the stream. With an added transform shader I could manouvre them in place. Used that to add to the function input of a displacement shader after the water shader. I then added another perlin (wave) fractal, blended by a 3x X-stretched perlin for some 'disturbance' in the flow direction of the stream. Used the internal displacement and decreased the color so some foam appeared on the tops.
The curly waves needed some foam as well, so I added a foam pattern fractal (you can use warped small scale ridges, or a set of warped voronoi blue nodes), blended by the first Z-stretched waves, but also added a transform shader (X translate 0.25m)  to move the foam a little off the tops and into the 'curls' I am anticipating. For the curls next in line I added a twist and shear shader, gave the X a lean factor of 2.
Next I wanted some foam where the water flowed onto the road right in front of you. So another foam fractal was used as a blender for a surface shader (white color, displacement offset 0.01). The fractal was blended in turn by a distance shader, so the foam would go a few meters, and not cover the whole stream.
Now the foam is white and not reflective, because the reflectiveness sits in the first in line water shader, so I could have added another reflective (RT) shader, but actually I didn't. I could also elaborate on the foam, which I didn't. Setting the surface shader that provides the white color to 0.5 or so, to make the foam more 'transparent' for instance, or adding tiny fake stones as 'bubbles'.... I didn't.

By the way; I made the road very wet near the water (reflective shader, reflectiveness 2 and a distance shader, blended by an enlarged soft river shape), and overall reflectiveness at 0.5. I first made the mistake to make the road wet by Ray Traced reflectiveness, but that took so long to render that I broke it of. 

A line of trees next to the road: used the same warped road shape, moved it X wise a few meters and hardened it using a color adjust shader. I also used this to make some sort of upheaval next to the road. If you want to do this properly you transform the basic lines before they are warped, by the way. And a distribution shader was used to place some copses of trees on top of the further hills.

It had to look rainy, so I made a soft fairly covered sky (two layers), and raised the light exposure in the camera to 1.4 (or it would be very dark). I also added a low very soft misty layer.

And of course I had to make the sign.

This render is a halfway iteration, next to come later.


Brilliant water and the roadside veg is just right.


Yeah, all really nice so far, but hold on, I'll get you soon! :-)


Ah, it's alittle NWDA inside NWDA contest?  :-\ ;) Looking forward to it.


Part 2; I added an extra surface layer with some rock/tarmac debris on the road sides. For that I needed another mask, so I made another soft simple shape of 3m wide, doubled it and moved one part 4 meters to the east with a transform shader. Then took it through a warp shader, with the same warper as the road of course (I am writing this down for TG users who are in the early stages of getting to know Terragen), which gave me two soft verges. I used this to blend two fake stones. I didn't smooth the surface layer or it would have smoothed away earlier displacements, such as the tarmac fine texture. But it seems quite nice.
I also hit the curly wave seed a few more times, as I didn't like the distribution. Two lines of poles were put in the fields, using Y stretched fake stones of 8cm radius, and a reduced variation in dispersal (0.1). Good enough for the illusion.
The tarmac surface was displaced -0.008 with a very hard billow fractal, so some worn patches were added. I also added some extra tiny fake stones (around 8mm) on top of the tarmac. 

There are some little issues; the car is not wet enough (my opinion, not the driver's), and the road on the other sides has some ugly verges.

So I made two versions of this iteration, one of them a little brighter. I wonder which you prefer....


The second, looks good..............


The road texture stands out, to me. Look at all the detail and imperfections (in a good sense) on it.

That's what everyone should take care of in their renders: anything that looks perfect, clean, or straight is going to give the rest away as CG.

Ulco, I think the roadsign seems a bit bright on the second render. Lacking any shadow, it looks like it has been postworked, if you know what I mean. It's just a tiny thing, but still. :-)



The Landrover is great. Is it a bit small in scale? Some broken up reflectivity on that sign might help address Franks point. I like the brightness. How about some water in the left hand valley where the river has broken it's bank and flooded the field?


Yes, there should be a shader called 'imperfections shader'. Just add it and you've left CG and entered the real world  ;) I don't know which one I like best, the first one is straight from TG and has a dull rainy feel, the second is a bit too bright, IMO. The sign was very dark when I crop rendered a sample, so I lifted its default colour to 1.5. Too much obviously.
With higher GI (this is the standard 2/2/8) the shadows might be a little better.
I'll take a look at the rover, I plumped it in, changed its size to 0.2, but never measured it. It needs some wet shine as well. I can also flood the field, no problem, good idea. I was already working on a second 'entry' (rockfall),  but will finish this one first.


Wow, that's just unbelievable, Ulco.  The water and the road (especially close to the camera) looks so real. Still can't comprehend how you can work so fast. Takes me a million crop renders to get just one thing right.

I'll sign onto the imperfections shader feature request. Matt or Jo, get on that quick, will you? :)


This would have been my final. Well, maybe not, as there are still some things I could change (more bush species for instance, more flotsam and stuff accumulated at the water's edge, some shine from the car's headlights in thin vapor above the water, a toy washed ashore, hinting at something terrible.....).