Monday, April 18, 2011

Difficulties .......

Well, i have just over one week left and a lot of work to do. I was working with City Engine in trying to sort out the export issues i'm having with it. When i export out a file, because of a limit on the size of the file, the file gets exported in parts. After a little bit of googling, figured out it was just a setting that i had to modify to get the whole scene exported as one file. This was needed as i had to start modifying them in Maya. Now that i have the whole scene in one file, the amount of time it takes for this file to load in Maya is a lot. I waited to get the whole file loaded and i figure out some interesting things happening with the scene. The way the exporter wrote out the data was such that, there are lots of disjoint meshes. The side wall of a building is duplicated in multiple places in the city, but all of these duplicates are combined in one single mesh. My guess is, this was done for performance reasons in City Engine, but i would be more happier if each building was a mesh of it's own. This will need some scene modifications in Maya from my part. I'm not sure how much time this is going to consume, but this might be mandatory for my grid segmentation.

It would be interesting to see if i can turn this off using City Engine, but i'm not sure if i have the time to invest in City Engine right now. So i imported the Collada file in Maya 2008 because the plug in i found works only with Maya 2008 and 2009. I saved it out using 2008 as a maya binary and opened it back on Maya 2010 64 bit. World of difference with respect to usability. Scene load time in Maya 2010 64 bit was much lower and inspite of the scene being big, i'm still able to use it freely without any huge drop in frame rate.

Long night ahead !


  1. Okay . Trying to export the whole city as one Maya file and breaking them up into chunks failed. Though Maya was able to handle the entire scene, the geometry duplication is so random that i will have to pick things by face and separate them into different polygons. Just not happening !

    Dumping the whole idea and moving to exporting block by block in City Engine. In short, i'm manually doing my segmentation in City Engine for a start totally eliminating Maya in the pipeline.

    Fingers crossed !

  2. It's important that you move on to the meat of your project. So if you are exporting by hand, just export a dozen or so models, which will be enough to test with. As the due date gets closer, go back and make a larger dataset - this way, you leave something easy (assuming your algorithm still works with the bigger dataset!) for the end.