advanced rendering for AutoCAD
I got an email from an old AR3/AR4 user who is considering the new nXt Engine
The forum here is excellent. There are many people who would be happy to give you a helping hand.
AR3/AR4 materials do work to a certain extent, but there are a lot of new features in the material creation process and I would recommend creating a new nXt material library as you go along.
The learning curve is quite small as nXt is easier and more forgiving than AR3/AR4. You don't need to be so careful with modelling (joining edges perfectly) and there is no more "moulding and trim" to worry about.
Lighting is also more simple as you don't have to place daylight sources. You can either use the automatic setting or simply pick the window glass as a daylight source. You can also select objects to be light sources.
Finally, the quality is far superior to the old AR. The level of realism is vastly improved (see below).
Thanks for the reply. I tried to reply earlier but wasn't a member yet so had to go through the vetting process. Anyhow, it sounds like the improvements have actually been improvements and the bad old days of light leaking through any edges that didn't touch perfectly are gone!
I think I will give it a go. In the mean time, one more quick question raised by your beautiful renderings above: are solids (particularly curved ones) handled fairly well now, or is it still best practice to build everything with meshes to control the number of faces?
I model everything in solids as it makes things easier to edit. As there is no radiosity involved, I don't know if it makes any difference how you model things. That's really one for Roy to answer.
Use whatever's easier. Solids plus some reasonable settings for facetres usually works just fine.
Just to clarify:
The top image is AR4 from 2007 and the bottom image is nXt last week.
Based on the advice below I have more or less decided to take the plunge and downloaded a trial to test with an actual billable project. We just did our first test rendering on Friday. A few initial comments:
Overall impression very positive. Have a few questions which I will put in another thread.
I always use a combination of daylight and interior lighting. Initially I set up the basic model with daylight sources only and test it before adding the interior lights. I then add the interior lights and test again before finally adding the furniture.
Thanks Peter. I always used a similar approach but did the first pass with just the ambient light which rendered super fast. Our current model has about 20 windows which I assume would behave like 20 individual lights thus slowing rendering time. Also, they produced tremendous glare which made the materials difficult to evaluate. I was just looking for a quick and dirty solution while getting the materials assigned, mapped, and tweaked.
I don't think the windows work quite like that. In fact, the more direct light you have, the quicker the rendering resolves.
Create a 600 x 600mm rectangle, turn it into a region and tag it as an area light with 200W.
Place it a couple of mm lower than the ceiling and then copy it around.
These types of light resolve quite quickly.
Also, use the path tracer engine as it immediately shows you the lighting and materials after only a few passes.
Thanks Peter. Good hints! I have to get used to a new way of thinking with nXt. Haven't even tried the path tracer yet. So much to try, so little time!