View Full Version : Facing ratio polycount?

02 February 2006, 07:02 AM
Hello mel GURUS.

Does anyone here know how to use the facing ratio node to tell the user exactly what the geometry ids are of everything that the camera can view?

Ok that's written a bit complex. But there must be a way to get the size of the geometry that which is currently being seen in the viewport through the facing ratio node.

02 February 2006, 08:34 PM
So you want see e.g. how much of the surface of an object is actually visible at a certain time? Like eg. get all faces that arent culled?

You cant do that with a facing ratio node as its a shading node. Shader nodes are only passed information that is actually required for shading. Such as the position, normal, uv coordinates etc. of the point that should be shaded.
But, like a fragment shader, it can only compute the value for that given position. Just like you can never tell which point will be sampled next or access any other computed pixel.

You can, however, for example query the normals of a mesh and the direction in which the camera is facing and get the angle between the two. If its greater than 90 the face is culled/not visible.

02 February 2006, 12:28 AM
That sounds great!

But I can't get it to work :(

Can you be a little more specifics on the steps to take if possible?

Thanks for the heads up on the shading node

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02 February 2006, 12:28 AM
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