Grass Tutorial by Chobs

Grass Tutorial by Chobs

Introduction:

This tutorial is inspired by Peter Uthrie and James Shaw.

Here are the links of their tutorial:

http://www.peterguthrie.net/blog/2009/03/vray-grass-tutorial-part-1/
http://www.peterguthrie.net/blog/2009/04/vray-grass-tutorial-part-2/
http://www.jamesshaw.co.nz/blog/?p=400

My version here is for the benefit of our fellow CGPinoys. The Difference between my tutorial and theirs have slightly to do with the Material and the Technique of distribution. Plus I used all free plugins. (no Vray Scatter needed)

It is also my first post of tutorial ever by the way! =)

What you will need:

1. 3D Studio Max – I use version 2009 32-bit
2. Vray Render 1.50 – I use the SP2 version
3. Advance Painter – This can be downloaded free in this link: http://www.scriptspot.com/3ds-max/advanced-painter
4. Itoo Forest Lite – Free also and can be downloaded at this link: http://www.itoosoft.com/english/menu.php?id=forestpack_description

Modeling the Grass:

1. Make a plane the best imitate the size of a single grass strand. I use approximately 10mm X 150mm. Then apply couple of segments. Not too much but just enough to bend it. Make sure your Gizmo is located in the middle bottom of the grass for consistent of Z location when we distribute it later.



2. Convert the plane into Edit Mesh or Edit Poly then choose the vertex on the top part of your straight poly. Use Soft Select to create a nice and smooth bend of the grass. You can also use Bend Modifier.



3. Make couple of unique grass bends. I use 5 unique Poly’s



Material for the Grass:

1. I use these Materials which I also downloaded in their site. Place them at the diffuse and reflect slot using VrayMtl.


Grass Mat


Grass Ref


2. Here is my setup on the reflection slot. I limited the ref to 100 and 0.65 Highlight Glossiness to save up time rendering. Of course you also don’t want a very sharp reflective grass, right.



3. After setting up the VrayMtl, make use also of the Vray2SideMtl since you are using plane objects.



And then apply Color Correction. This will be our base material to be duplicated within the MultiSub Object Material that we will make.



4. Depending on the number of unique grass that you made (Mine is 5 right). Create a MultiSub Object and set the number of material within slot (I made 5) and apply each to the grass that you made using Material ID. Drag and drop your base material to the other slots and just use “COPY” not instance otherwise that colors won’t be different from each other. Then adjust the color of each material to have more than one shade.



Making the Grass Tile:

1. Make a Plane 150mm X 150mm with 1 segment on width and height.
2. Using the Advance Painter, randomize the grass that you made in the 150mm plane. On this plane I think I only limited my grass up to 500 strands. You can also use the default scatter of 3ds max if you are not comfortable using Advance Painter.



3. When done and happy, merge all the scattered grass onto one mesh entity. (Don’t include the Plane)

Distributing the Grass Tile in your Scene:
1. In your since make a closed spline where you want to distribute your Grass Tile.



2. Using Itoo Forest Lite, pick the spline where you want your grass tiles to be distributed. After which, on the Geometry Rollout under Forest Modifier list, pick the Grass Tile that you made to the Custom Object.
3. In the Distribution Rollout, choose dense for the distribution map then adjust the X and Y size. Adjust also the parameters on the Transform Rollout to the preferred setup for more randomized effect.



4. When happy setup render then test render it!!! =)

Important Note:
1. No need to convert the grass tile to VrayProxy. Itoo Forest will automatically make it in the scene.
2. Using the Limit Visibility under Camera Rollout in the Forest Modifier is advisable since it will hide lots of Geometry out from the camera view.

Pro’s and Con’s

Pro’s – I think the advantage of this one is that evidently it will look more realistic than the conventional displacement method. You can totally manipulate the color also of each strands that you make and it does not only limit you to creating grass but also small flowers.

Con’s – Well I haven’t tried to test the difference between the render time of this technique versus the displacement but I am assuming that since we are using meshes here this will be slightly render longer. Another limitation of this is that I can not distribute the Grass Tiles in a non flat surface unless you have VrayScater or the licensed Itoo Forest.

Samples:

Here are samples of the application of this technique.

http://www.cgpinoy.org/architectural-f3/afternoon-delight-rendering-practice-t7623.htm?highlight=afternoon+delight

http://www.cgpinoy.org/architectural-f3/phuket-mansion-2-storey-house-t7816.htm

Feel free to drop your comments.

Cheers and Mabuhay CGP!

WOHOOOOOOH thanks a lot chobs hehehe

sir good day..
hope you are the one that can help me.. i am working in a golf course company and we need to produce a rendering and animation..but then its hard for me to produce it..please give me your ym and i will be giving you the drawings,,,that is if you want to..thanks..\


hope to hear from you soon

Thanks for the reply Pips. Hope this tutorial will help you in your rendering. Cheers!

bokkins wrote:Thanks chobs, gand nga nitong gawa mo. keep it up bro!

Thanks Bokkins. Just sharing my knowledge to the pips.

We learn by giving and receiving. Para Xmas quote lang. Hehe...

lord_clef wrote:sir good day..
hope you are the one that can help me.. i am working in a golf course company and we need to produce a rendering and animation..but then its hard for me to produce it..please give me your ym and i will be giving you the drawings,,,that is if you want to..thanks..\


hope to hear from you soon

I'll try to give a hand on that. Just PM

thanks for sharing chobs very much appreciated.more power bro

Salamat...isang dagdag kaalaman..

Pinoytaasnoo ka

thanks master malaking tulong to

Nice & thanks a lot sir.

ang galing mo talaga lakay!!!!!!dapat on the spot cgp guru kana iilan lng gumagawa ng mga tutorial na tulad ng ginagawa mo... simpleng halimaw ka!!!!hihihi..aabangan kona mga gawa mo!!!!

nice one

very informative............thanks for sharing this stuff!