Alphageekgirl's – modo magic website – Positioning grass or fur around objects

April 28, 2013 Posted by Debi in All Articles, Grass, Neat tips, Replicators, Step-by-Step

Positioning grass or fur around objects


Description	Replicators are a great feature in modo allowing us to replicate an object multiple times using a fraction of computing resources. When it comes to grass or fur you can sometimes have a problem that is referred to as interpenetration. This is when you have say grass that grows around objects like rocks or pavers. . Alessandro Masciari has written an excellent, detailed explanation of how to overcome this problem. But in a nutshell... Note: this method was created during the 601 era. You can see Andy Brown demonstrating this example using procedural tools (at ~18 mins) using MODO 10.1
Step-by-Step	Place the grass into a Group Create a replicator using the Grass group as Prototype and the ground item as the Point Source. Hide the grass from the renderer by unchecking it under the Group tab Create an Ambient Occlusion Render Output Set the Frame to be square Create a map and bake to render output In the Shader Tree, inside the Ground material group, create a Surface Generator Load the AO image into the same material group and change its effect to "Surface Particle Density" Under the Replicator Properties tab, substitute "Ground" with "Surface Generator"
Source	http://kroncept.blogspot.com.au/2011/07/grass-around-objects.html
Author	Alessandro Masciari