View Full Version : Grass Look-Wip.

07 July 2010, 06:50 AM
Hello there, I'm doing this scene which has a lot of tufty grass and though I'm inclined to be satisfied with the grass done so far, I have a feeling that something is quite not right about it. I think that it's the scale of the grass. I put those two white blocks to represent the height of an average human and sometimes when I look at it, the scale seems alright but at other times not so. I don't think I can go far like this. I'm really confused. Do tell me if the scale is alright or not. And also, do the grass in itself look ok? When I zoom out they seem to be too lumpy but not so at close up. Like in the image I posted along.*

I'm using blender 4.9b for this. I'll furnish any other data if needed.

Any critique will be much appreciated. Thank you very much.


08 August 2010, 05:11 PM
I think the problem is that you have a lot of "lumps" in there. Is that on purpose? The grass should be more or less even; varying height and angle but not such mid frequency lumpiness. You could also intersperse some random dandelions or other weed. This will also help give it scale.


08 August 2010, 06:31 PM
Thanks for the reply Wiro. No. The lumpiness is not intended. I'll be removing them. But I quite liked this grass up close. They don't look very lumpy then.

I was planning to add the flowers after I fix the scale of the grass. I don't think my computer can take anything with this at the same time. Do you think the scale of them is right at the moment? Will a person of the blocks height look natural if placed of the grass?

Thanking you,

08 August 2010, 11:29 AM
Yea I think up close (as in right among the characters?) the lumps would look fine since you don't see as many of them repeating. What is causing them though? Are you using a noise fractal as a length or density map?
If so it may be enough to just break it up more.
Other than that, from this angle the grass scale looks fine to me.
How about you look through Flickr and see if you can find some similar photos for ref?


08 August 2010, 08:49 PM
There are several problems with the grass. It's too homogeneous in color, real grass has more color diversity because its partially transparent so some blades have a lighter shade of green, and it's also quite specular so there should be lots of sky reflection visible in it. If it's wild grass then it should be mixed in with at least 5-6 other types of grass or weed plants, dead blades, leaves, and should be allowed to bend over; only lawnmower cut grass ends by sticking up straight, and only freshly after being cut does it do that.

08 August 2010, 02:05 PM
Thanks for the reply Wiro, stuh505. Wiro, that's what I meant, right among the characters. The lumpiness are not made by a texture. I found that texture affects little of their behavior.

Here's an update.

I divided the previous grass plane into 3 and added the same grass system so they'd be denser and then render each patch separately and then composited them together. I also reduced the width of the blades. It still looks uniformly lumpy to me when the grass gets away from the camera but I think I can remove them by reducing the noise in the grass patch the farther it gets from the camera. Am working on that now.

stuh505, I agree I have a lot to change. I thought that I could nail this basic grass and then add the variants. Will work on that soon. Thanks again for the reply.


08 August 2010, 11:10 AM
hey there, I managed to make it less lumpy added some specular hilights and made the colour to vary a little.

here's it,

Thank you.

08 August 2010, 01:18 PM
That looks a ton better!
Still the overall color is a bit off, too rich of a green...grass has more of a yellowish hue, and the specular color should be pure white not yellowish-green.

08 August 2010, 06:47 AM
Thanks stuh505! I tried putting the spec to white but ended up getting white grass strands among green. I'll try putting a more desaturated spec color.

I looked again for some reference and I came across this and have decided to imitate it's colors.

Will post an update soon.

08 August 2010, 09:23 AM
That looks a lot better, much nicer variation in the lumps and the colours look better too. But stuh505 is right about the spec, it should be white. The only specs that aren't are metallic and that's kind of what your grass looks like now with the yellow spec.
If you were getting too white highlights and you have tinted your sun yellow (which by the looks of it is the case) then your specs were just too strong.


08 August 2010, 10:51 AM
I just wanted to say - that is the most amazing grass i have eveer seen :)

08 August 2010, 09:33 AM
Okie-Ozolinsh, thank you!
Wiro, Thank you very much! You are right, my spec settings are very high. I'll set it back to white and try again with a lower value.

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