For many years I have been using XM raytrace to generate aerial renderings of urban design projects. My workflow includes the creation of an image-draped DTM, simple massing models of buildings and street trees, minimal materials. Some examples - http://communities.bentley.com/products/microstation/microstation_visualization/m/luxology-gallery/171980.aspx
The graphic quality is “real” enough for the design intervention not to look out of place in the context of the real aerial imagery. I’m happy with the results but keep feeling I should put my select subscription to work and try out Luxology.
The example below is a test case comparing the two rendering techniques. For the purpose of comparison I’ve set both to render low resolution without anti-aliasing and both to include open elements (in Luxology this is a modified version of the Exterior Good setup).
The first thing to note is that Luxology took almost twice as long to render (2min 44sec) compared to Raytracing (1min 18 sec). The first “out-of-the-box” Luxology rendering (V2) is quite obviously too dark so I have switched off Photographic Tone Mapping and adjusted the brightness/ contrast sliders in the second version (V3) of the Luxology renderings. I also switched on the “Auto Gamma Correct Color Maps” in the Light Manager. I have not managed to get Fog to work – mainly because I don’t seem to be able to make easy setting changes (like fog density) and hitting Raytrace current solution as I could in XM to see the effect quickly. Luxology seems to require many more tweaks and long waits to see improved results. The right-click to abort rendering is instantaneous in an XM raytrace, but “Cancel Luxology Render” in the Luxology interface is extremely slow to respond. In fact, all interaction with the Luxology render window (calling up the Environment Settings, Luxology Image Settings, etc. ) seems sluggish.
I’m sure I’m wrong, and these are just newbie niggles, but here’s my question – should I stick with what I know (ie. XM raytracing) or persevere and get Luxology to work for me?
This is the way it should look....
If I understand you're story, you compared the renders with the same render settings. In this case the good old Ray tracing can indeed give better results. You need to change some extra settings to best use Luxology. Try the following settings and I think the quality of you're images will be even better than they already are:
Water reflections:Look in the material editor if the reflect is on (min 10). Further is it important to minimal use exterior good in the render settings.
Shadow to dark:Use an environment. This will increase the realism of you're model dramatically. There are some very good standard settings. Try for example Probe Alley. With the Quick Preview Tool you can see almost instantly the result. Increase the Lux (Environment Settings) to decrease the shadow strength.
Tip 2: Increase the cloudiness (Lightmanager - Solar - Cloudiness) try 85 - 95 percent)) to decrease the shadow strenght.
Tip 3: At the shadow option in the Solar Settings try for example Soft Medium.
Fog:I agree that the settings for fog are complicated. I many often simply use a depth map (Render settings - Render Output - Depth) and use the generated image as a mask with a white / grey layer in Photoshop. Very simple and you can tweak the fog instantly and non destructive.
Contrast:I red that you already used Auto Gamma Correct Color Maps. Try to experiment with the environment settings.
Hope this works.
Thanks very much for your reply. I'll certainly experiment with your suggestions.
The first thing that discouraged me was that the out-of-the-box settings resulted in slow rendering times and experience tells me that the more one tweaks settings (adding an environment, etc) the longer those times become. Having to take fog into post-production extends that time even further.
Still, I'll give it a go and see if I can get the results I'm looking for.
Have you tried the Populate content tools in the Visualisation tab (08.11.09.173)? In you're example file I see a lot of trees. For the placement of cell's this function can save a lot of time.
Further do I think that the stencil selected elements tool can save a lot of time for the placing of marks.
A nice extra tool are the traffic lane tools. With this tools you can place cars on a road in no time. If you click on the play button of the animation preview tool, it's also directly animated.
Maybe this new set of tools can compensate the longer render times of Luxology a bit..
What are the specs of your machine, number of cores, memory?
We create a scene file that is then sent to the render engine and in your case this could be taking most of the render time and this process is done in MicroStation which is single threaded, I don't know what resolution you are rendering but at higher resolutions Luxology would likely be faster if your machine has enough cores.
The performance speed up with Luxology is almost linear so a quad core will be about 2X improvement over a dual core. If you have newer I7 based processor, turning on hyper threading will provide a further ~ 20% improvement in rendering performance.
If you want your water to look realistic you need something to reflect so use an environment physical sky, gradient sky or a sky sphere.
In the render setups to choose from you should be picking Exterior Good and not Ray Trace.
The resulting rendering is a floating point image (BIMG) and you will need to adjust the tone mapping. If you have a named light setup these adjustments can be pushed back to the light setup by clicking the the top left icon in the adjustment dialog. You can also push these into the untitled light setup but you will have to remember to save settings before exiting. If you do this the next time you render the image should look like you want because the tone mapping adjustments have already been adjusted.
As far as the crispness of your line work goes there are several different anti-aliasing methods to choose from in XM the default was Box you can try that one by simply switching it in the Render Setting dialog for the setup you are using (Exterior Good).
Indeed! Those tools go a long way to make me more interested in moving forward with the new versions & Luxology. I've come across them but not yet put them to use. Really looking forward to getting off the production line on a current project so I try these things out (as well as your earlier rendering suggestions).