An Introduction To 3D with Lyndon Daniels

Part 7: Rendering and Final Output

Hardware vs Software Rendering

In computer graphics there are two main types of rendering; Software Rendering and Hardware Rendering. We have mainly been using hardware rendering to model our head and the effects of this can be seen in the 3D viewport. Hardware Rendering utalizes specialied hardware such as a graphics card including a GPU (Graphics Processing Unit) to simulate the final output of our model in realtime.
This is, however, not always a practical approach to visualizing the final product as,
iHardware Rendering is limited by what the resources of your system can compute in realtime.

This is mainly useful for output to games engines and other realtime 3D applications, including the 3D viewport within your modelling software. However, in a complex scene with high resolution geometry it becomes increasingly difficult for your computer to display the scene in your viewports in realtime.
Your 3D software must therefore limit the amount of information that it displays in your viewports, so that when you interact with the scene your software and hardware can update it at a reasonable speed.

Looking Ahead

Of course it would be great to see the results of your work smoothly shaded, textured, with reflections and interacting with a full light set in the 3D viewport, that is to say, as close as possible to the completed rendered version, however, this is not entirely practical at present.
While aside from the physical computational limitations discussed, standardized methods of abstracting low-level hardware interactions and how they are utalized by software developers along with GPU manufactures would all need to cooperate with a greater degree of transparancy. This could potentially be viewed as a risk by many propriatery software and hardware vendors.
iHowever, on a lighter note, as the technology we use to produce 3D advances the distinction between hardware rendering and software rendering is constantly being challenged with the gap becomming smaller, perhaps largly driven by user demand.

The 3D gaming industry provides a fine example of the pioneers that test these destinctions by constantly pushing the limitations of realtime rendering, as games become more cinematic and life-like and the definition of hardware rendering versus software rendering becomes less of an issue for the end user and content creator.

Practical Rendering

iWhen software rendering an animation or a high resolution file for print you would tend not to work on the file during the rendering process.
This is still a part of the creation process as it can take a considerable amount of time to render an image sequence or a high resolution image, even though the 3D software you are utlizing requires no further input from you.
It is worth considering that rendering is a part of the creation process and an integral part of completing the project, subsequently when determining a timeframe for working on a project rendering should always be taken into account, even if that means you're off somewhere having a coffee, beer or smoothie while your computer is chugging along.
When you have completed your model and are ready to compose your shot consider that the process of rendering can be broken down into several basic sub-catergories,
  • Texturing
  • Composition
  • Lighting
  • Rendering