# How to call vertex groups in Animation nodes [SOLVED]

I would orient some instances by vertex normals, but i'd like to control orientation by vertex groups, to give z negative values to some instances, like in the pictures.is it possible? i've tried with Vertex Group Input but it gives me unexpected results.

Solved by 3DSinghVFX, then i've added a Combine Vector to control also Guides parameter from Vertex Group Input.

You can achieve that effect by controlling the scale of the normals with the vertex weight.

1. First, instanced an object (Cone) on the vertex locations of the base object (Cube) using this node-tree:

2. Then, remap the weight (using Vertex Weight Input node) which is in range (0, 1) to (1, -1) using Map Range node with the Threshold (in Threshold node) = 0.5 i.e., vertices which have weight less than 0.5 will have normals with scale = 1 (+ve direction) and vertices which have weight equal or greater than 0.5 will have normals with scale = -1 (-ve direction).

You can very the Threshold as you like.

Blend File:

• Thanks, great! you are the man :) , there are also some other ways to call a group of selected vertex to give them parameters? maybe i need to create a new question on StackExchange? – mike Nov 14 '19 at 19:29
• Vertex Group Node gives the weight of all the vertices or vertices specified by indices. For selected vertex: you first assign a weight to the selected vertices then later you can filter them using Vertex Group Node and Mask List node. If you want to know in more details then please create a new question. – 3DSinghVFX Nov 15 '19 at 9:13
• Thanks, i posted a similar question linked, because i'm trying to orient instances in more complex meshes than a cube:blender.stackexchange.com/questions/158093/… – mike Nov 15 '19 at 18:04
• Please accept the answer of this question if you satisfy. I'll try to answer that question. – 3DSinghVFX Nov 16 '19 at 9:37
• Ok, i did not know 'till now that one has to accept the answers. Thanks, done! – mike Nov 16 '19 at 18:46