VRAY vs Octane Render: the challenge of 3D rendering engines

Differences, pros and cons between the two most used softwares for rendering three-dimensional models


Rendering engines are fundamental components for all those involved in 3D modeling: they are in fact softwares that focus on calculating renders, supporting traditional modeling programs and  producing photorealistic images.

The problem, especially for those who are new to this field is that it is not always very easy to choose one in particular.

We decided to focus on the two most famous and most widely used: VRAY, developed by the Bulgarian Chaos Group and used by numerous graphic programs (such as Studio Max, Maya, Rhinoceros, Cinema 4D, Softimage XSI, SketchUp, Blender) and Octane Render, such as OTOY, a startup based in California which can be integrated, for example, with Autodesk 3D Studio Max, Maya and Lightwave.

Before comparing them, let’s talk about the theory behind 3D rendering engines.


CPU and GPU Rendering engines

There are two large families of 3D rendering engines: CPU and GPU based.

In the first one the processor is  responsible  for  the rendering process while  in the second one, video cards are in charge.

The most obvious difference between the two methods is the amount of operations that can be performed simultaneously: a CPU can do from tens to hundreds operations at the same time, while a GPU can do up to thousand different ones..

The second difference concerns the use of memory. This is the main weak point of GPU engines.

They use VRAM video cards which  reach a maximum of 32 GB in the case of the most expensive nVidia.

CPU engines, on the other hand,  take advantage of RAM memory. Even a regular personal computer can  be easily expanded up to over 64 GB.

This can cause several limitations: the more memory is available, the greater polygons can be rendered in the scene; the higher the quality of the textures, the greater the size of the rendering and the wider the quality of solutions such as fur, displacement , motion blur etc.

Even for compatibility reasons, render CPUs have some advantages. They can be adapted to any type of processor on the market. On the contrary, many GPU renderers use only CUDA technology which can only be applied to nVidia video cards and not to AMD / ATI cards.

In the end we can say that for a CPU based rendering engine you need a processor, a motherboard and a high performance  RAM.

However,  you can save on the video card deals basically only with the viewport view. In the case of GPU Based engines, the processor is used to load scenes and geometry.

Its performance is important, but much less than those of video cards, which deal with the rendering process.

The motherboard, in the latter case, may not be the best, but the advice is to buy one with many PCIexpress slots, in case you want to upgrade the system later on by adding new video cards.

For this reason, investing in a GPU engine is normally more expensive, at least initially We have considered two engines so far, VRAY  which is CPU based and Octane which is GPU based.


Pros and cons of VRAY and Octane

We also highlight  pros and cons of using  VRAY vs Octane.

VRAY, for example, is considered the most flexible engine, because it allows to recreate any type of scene and support many different tools and plugins, but also many materials and mappings, while Octane is much more limited.

However, based on the configuration of the renderings, Octane is better  because it allows to get satisfactory results even with much simpler settings; as well as avoiding all problems (being an Unbiased motor) such as spots or flicker.

This could only be eliminated with a lot of work and effort when using VRAY. On the other hand, as for the use of memory, VRAY seems to prevail, because it uses RAM instead of the limited VRAM.

Other advantages of Octane are lighting, camera and exposure.

You can achieve real results with both engines, but by using VRAY this operation can be much more complicated and less intuitive, especially for the less experienced ones.

Finally, as far as network rendering, the advantage of choosing Octane is that of using only the video card for ( che  e’ secondary pc) secondary computers: it will only be necessary to purchase the software license, but not those for the plugins.

In short, VRAY and Octane have very different characteristics and each one suites different situations.

The advice, if possible is to learn to use both, so you can use them in specific occasions.