Me Again! Peter Chapman. if it s important / time-sensitive

Transcription

1 Me Again! Peter Chapman if it s important / time-sensitive Issues? Working on something specific? Need some direction? Don t hesitate to get in touch

2 Rendering theory & practice This can be the most time consuming part of the process depending on the complexity of your scene Many people underestimate the time needed Can easily be a massive time-drain!

3 Introduction Scene complete = time to start rendering! How do you want to render it? Should think about rendering all the way through your production don t leave it till the end! Create models and textures with the final image in mind Gear lighting towards showing off the scene Which renderer? Maya software, Maya hardware, Mental Ray, Maya vector, Vray, Octane

4 Different Renderers Each engine renders differently and can give entirely different results Choice depends on: the final look you want number of machines you have Number of licenses you have Time / Budget It s best to choice the render engine before you begin creating your scene and essential before lighting and shading.

5 Some Basics Choose an appropriate resolution and aspect ratio where will the final output be displayed? ALWAYS Render to frame files rather than movie files Open iff from maya, or png / tiff but never jpeg! Use file formats that use no compression or loss-less compression Use anti-aliasing (within reason) Use Ray tracing wisely (expensive) Don t just ramp everything to max! Be smart!

6 Which is best and why? discuss

7 Maya Software Default software rending solution Can capture just about anything you want in your scene Reflections, Motion Blur, Transparencies Good one to start with Render quality depends on anti-aliasing and ray-tracing Often under-estimated Can be fantastic when combined with an occlusion pass

8 Maya Hardware Uses your graphics card s processor to render (but not the same as GPU renderers such as Octane) Similar to what you will see when you play a 3D video game Data output by the game is fed directly into the graphics pipeline and rendered on the fly as you play. Results in faster render times, but lacks some of the features and quality you get from software render Don t use it

9 Mental Ray Now included and heavily integrated into Maya True Physical render engine allows amazing realism Emulate the behaviour of light more realistically Can be an advanced renderer with shaders and procedures of it s own Can be used to generate occlusion passes

10 GPU Renderers (Octane / Vray) Use advanced GPU s (usually Nvidea CUDA cores) to render very quickly and realistically using the architecture of a GPU hundreds (or thousands) of cores doing simple things rather than a few powerful cores such as a CPU Requires using it s own shaders / cameras etc

11 Global Illumination This simulates the interaction of light with the entire environment rather than individual surfaces Light is tracked from emitters to sensors Shadows are automatically generated, as are interactions between surfaces There are two common approaches: ray tracing and radiosity Before we look at these in detail, we should look at some general features of global illumination

12 Global Illumination Ignoring the fact that the calculations (as we shall see later) are complex, the solution to global illumination is simple: Start at a light source Trace every light path through the environment until it either: Hits the eye point Has its energy reduced below a threshold Travels out of the environment

13 Surface to Surface We can also model the way one surface interacts with another This is easier to consider non-mathematically Four different interactions: diffuse to diffuse specular to diffuse diffuse to specular specular to specular Colour bleed, colour in shadows, etc

14 Raytracing

15 A Classic Ray-Traced Scene

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18 Simple Rendering Best Practice Model & Texture appropriately Level of detail needed not over done Close objects high detail objects further way less Use line render, play blasts, test renders Avoid mistakes re-rendering costly Only use features necessary Paint effects, final gather etc all take time Split your scene up Multi-pass / Batch rendering / Network Rendering / Distributed Rendering where appropriate

19 Questions? Course Industry Me Anything!