Iray lighting and surfaces for simple geometry

knuckledusterharris_b01188de76

In Iray, what is the best way to set up surfaces and lighting for the following scenarios? In other words, I want to use models with the simplest geometry possible, dialing in surfaces instead of using UVs when possible, but I want good lighting results.

A: Simple plane with four vertices and one surface (for instance, a wall that has wallpaper)
A1. With texture loaded to the base color.
A2. No texture, using only the surface characteristics as dialed in (is this even possible?).

B: A complex plane with a subdivided mesh of many vertices or a cube/sphere/or cylinder with many faces.
B1. With a UV map (I'm assuming, since you can't apply a texture image to a multi-surface model without a UV map as I understand it).
B2. No texture, using only the surface characteristics as dialed in (I'm assuming this requires a pretty high poly-count model for good results).

I will post a separate thread for the answers as they relate to 3Delight.

JonnyRay

The same answer actually applies to both rendering engines; so I will post in this one, and note the minor differences for 3Delight.

For a plane, the number of polygons doesn't actually matter. And if you are creating the other primatives in Studio using the "Create -> New Primative" function, then Studio creates a default UV map for them. Whether or not that UV map works for a texture image you want to apply might be another question.

Texture maps are mapped in U and V coordinate space ranging from 0 to 1 no matter what the dimensions of the image map are or how complex/simple the geometry is. The main differnce you might see is that a smaller texture file could appear stretched or distorted across a larger surface. That's where tiling can come into play as that replicates the texture multiple times in either the U or V dimension (or both if you choose).

Setting up surfaces using the default Daz 3Delight shader or the Daz Uber Iray shader is basically the same whether you're using a texture file or not. It's just a matter of getting used to what the Base (Iray) / Diffuse (3Delight), Glossy (Iray) / Specular (3Delight), etc. channels do and how to best use them for the effect you want. I will create a simulated room all the time using simple planes and applying paint shaders or something to the walls. It works just fine when I don't really care what's behind my characters, I just want something to be there.

You can set these surfaces up using nothing but color values from the color picker or you can click on the map button and select a texture map to apply to the channel. Keep in mind that if you apply a texture map and a color in the same setting (say the Base Diffuse color) then the color is multiplied against the texture map. That can work to your advantage though as it allows you to tint the texture map if the map itself isn't exactly what you wanted.

You mention wanting to get good "lighting results", but technically surface setup and lighting are seperate controls which interact with each other when you render them. You can have wonderful detailed surface settings and give you only light the scene with the built-in "headlamp" on the camera the result will look awful. So learning proper lighting setup is going to be part of the learning curve as well and will vary WIDELY depending on exactly what you're trying to accomplish.

There is no "perfect" or even "ideal" setup for surfaces and lighting that will work for every scene and situation you encounter. It's mostly going to be about learning how to use the tools that are provided in Studio and working with them to achieve your desired result.

knuckledusterharris_b01188de76

Thanks that does help. I'm just starting to become aware of the interplay between lights and the geometry they are lighting when it comes to renders. I'll set up a scene with basic shapes and a spotlight and do some experimentation.