seemingly seamless/tiled patterns

[joconnell]

Getting results now too with the grass bits on cgtextures - using two 3000 x 2000 textures, one rotated 45 degrees and scaled up to around 115% and a noise for the mix map - cheers for the clear instructions, it's gonna make one thing I'm working on (which has 50% of the time it should) far nicer - much appreciated.

[tricky]

You should be using the texmapmap in the modifier.
Have in mind also that 2D displacement doesn't work very well with real-world mapping coordinates,

Is this true? Why so?
Also, what is the need for the Displace slot in ME if I should be using the texmap slot? Sorry for my ignorance.

[Codi]

I had an issue with 2D mapping an RWMC some time ago and and as far as I know it isn't fixed:
http://www.chaosgroup.com/forums/vbu...ad.php?t=30529
Not much of a problem, just avoid using a tiling different than 1.0 1.0 in the displacement bitmap and it works fine.

If you look at the modifier, when you set VRayDisplacement to 2D mapping, the option "Use map from material" gets disabled (because it's specific for 3D mapping/subdivision), so it always uses the map that is specified in the modifier.

[tricky]

I see. That is annoying - we've been using Realworld mapping for a few years now and it saves a lot of time. Oh well, I'll remember next time I try displacement. It could actually be a reason for maps not aligning with diplaced geometry (another thread I think I started!)

[robman321]

Are you getting flickering while animating? Are you using Vray Fur? Can you walk me through this setup? thanks, rob

[robman321]

Can you walk me through this process? Where do the maps go, which maps, does this render flickering in animation? please help. -rob

[beestee]

For the sake of different maps and familiarities with the tools in max the approach will be slightly different for every user. The concept as I understand it is that you will mix multiple diffuse grass textures that are at different scale and rotation. You can also do the same with the displacement to introduce further disruption to the tiling.

The simplest approach is by using two diffuse grass maps in a mix map, and a standard noise map as the mix amount. You can even use the same grass map with a color correction map to slightly modify color if you wish.

Now where I believe a lot of confusion is coming from is in the set up of the UVWs:

In the real-world UVW approach, you will be setting the different sizes and rotations in the grass maps themselves.

In a standard UVW mapping approach, you will have to use map channels in the grass maps and multiple UVW maps set to corresponding map channels, then adjust the size and rotation using the UVW modifiers.

In both approaches, the size of the noise map used to mix the diffuse grass maps, and the scale of the grass diffuse maps are the keys to getting a believeable result in terms of scale. This will take some trial and error to get the balance correct.

As concerns animation flickering, it is a different topic. Generally in my experience animation flickering in grass materials roots itself in the anti-aliasing settings of the bitmaps and/or render settings. There are plenty of threads covering this problem more specifically.

[jujubee]

LOL Eric.

[pnel77]

Vray Displacement (2d) Grass - Shadows

Hi there - I've got a bit of a problem when it comes to shadows being cast on the displaced grass (plane with 2d Vraydispmod):

In all the camera views the shadows appear correct - dark shadows to simulate middle of the day sun settings - except when I set up a camera viewing directly to the sun position.
(see images)..

Obviously the displaced grass blades are casting their own shadow which means the object shadow are completely lost - not very realistic??

Please help me out - The only way to get some object shadow to appear is to lower the amount of displacement (60mm in this scene) - but then the displacement effect gets lost.

Any ideas?

Regards

[grasshopper]

Firstly, thanks cubiclegangster. Great method and explanation.

Does anyone know a way to use this process to create a mowen (stripey) lawn? Doesn't really have to effect the displacement but would be nice.
I would normally manage to do it in post but the ground I'm working on is very contoured. Some sort of way to effect the colour balance across half the bitmaps above the mix map I presume I just can't work it out.

[dbuchhofer]

I tend to just do a VraycompTex set to multiply with a light gradient ramp as the second item

OR, if i'm already in a blend material, i add it in there.