X S I grass tutorial

Since version 2.01 of Softimage|XSI we have excellent support for hair. Although the name of the system is "hair" you can use it to create a lot of different effects, and in this tutorial I will try to explain how to make grass with it. Click here if you want to see a picture of the final result.

1. Start with a new scene and add a grid by clicking:
Get->Primitive->Polygon Mesh->Grid Close the window that pops up.

2. Select the grid (if it's not already selected), go to the hair panel and click Create->Hair->from Selection

3. In the window that pops up go to the Effects tab and type in the values shown by the image below.
For a more detailed explanation about the different sliders press the ? button up in the right corner of the window. If you want to see this window later on simply select the hair and press [Enter]

4. We will now look into some settings for the grass shader, so simply close the hair settings window and click Render->Modify - Shader In the window that pops up type in the values shown by the image below. How you set the colors really depends on what kind of grass you are after, but for those that don't want to tweak it themselves copy the RGB values displayed in the image below.

5. By default the "hair" is a bit transparent both at the tip and at the root, but since that isn't right for grass simply go to the Transparency tab and set both Tip Transparency and Root Transparency to 0 or close to 0. If you set both values to 0 you might as well uncheck the checkbox "enable".

6. This is it, you should now have a finished grass scene, but don't feel locked in to the settings and values I have in my scene, instead try to experement a bit and see what happens if you change something. If you would like to have the scene for this project you can download it here.

If you have questions or anything feel free to mail me, the address is andreasbystrom@telia.com