renderman | Julius Ihle

Smoothing dotty Specular Highlights in Motionblur

September 20, 2016 Uncategorized 8

One of the worst things to sample for any brute-force ray tracer are specular highlights / reflections with a low roughness in motion blur. Even worse so on fine displacements or bump. And EVEN more worse with lots of small highlights. When all of these things come together sampling these highlights in motionblur is going to become really hard and with conventional methods you will end up having to rely on extemely high AA samples and even then the highlight-streaks will most likely still be dotty… And you won’t make any friends if they have to paint these streaks smooth in Comp :) So during the crunch time of a recent project I was brain storming with some of my collegues how this could potentially be fixed without needing too much samples and I’ve been working on implementing that idea which seems to work quite nicely.

Sampling in RenderMan/RIS

July 5, 2015 Uncategorized 2

The new RIS mode introduced in RenderMan 19 is a completely new render-engine that is very different from REYES. Being a brute force path tracer (uni- and bidirectional modes) it works much more like other renderers that follow a similar approach (e.g. Arnold). That approach aims to make the render process more simple and interactive. And while I personally don’t like it completely yet it seems to get widely adopted in the film industry and we all have to adjust to it sooner or later :)

More Katana Macros/Tools

February 28, 2015 Uncategorized

During the last year I luckily had some time to spend on digging a bit deeper into Katana. From working on assets and shots I experienced some moments where I thought it’d be great to have some basic tools to help get the job done just a little bit quicker. So whenever I had a bit of spare time I was developing some Macros/Gizmos/Tools to help artists on some common problems.

Texture Conversion in the GUI for Arnold & PRMan

December 28, 2014 Uncategorized

In the process of trying to streamline things a bit more in my day-to-day workflow I have recently been working on a hand-full of small helper tools. One of them is a small set of scripts that handle the conversion of a selection of files to Arnold & RenderMan’s native .tx/.tex files from the filebrowser… because people like the GUI, right? :)

Simple PrimVar Helper Script (updated)

September 14, 2013 Uncategorized 7

Primitive Variables are a really cool way to get variation in Renderman Shading Networks. As it requires adding Attributes to your Shape Nodes within Maya to control the variation it can be quite time consuming to set it up. So I was trying an attempt to build an interface that helps a bit with the set up.

Dirt AOVs with Yeti & PRMan

August 3, 2013 Uncategorized 2

CG fur always has the tendency to look very clean and soft. To break up the structure and to give a bit more realism I like to mix it with a bit of dirt, e.g. some leafs or sticks in the fur of a character walking through the woods. Here’s a quick rundown on what I’m doing to achieve this using Yeti and Renderman within Maya.

Automatic TEX Conversion

June 28, 2013 Uncategorized 1

To render more efficiently and to get some particular features working one has to feed Renderman with .tex files. Most regular image files can be converted to .tex files with the txmake executable that comes with RPS. However converting multiple files such as UDIM’s from Mari can be time consuming. So let’s make things a bit quicker… :)