I am having a problem with a "floating point overflow" error coming up when I try to do a Lighting Analysis on the 3d grid. I tried exporting the file as a .mod and then importing it back and re-saving as a .eco, but still have the problem.

The error occurs when I try to analyze the "L" shaped part of the building which I have the analysis grid fit to. I am trying to look at how different skylight types and layouts would light the space. I should note that I had originally imported a roof with skylights from ArchiCAD, but the roof and skylights became very complicated and triangulated (because of their complexity from the ArchiCAD model)and had something wrong with them (they would not even show up in the visualize screen). So I made the roof and skylights as a single plane within Ecotect and put it on the "simple back roof". Is there any problems with doing this within a model that has been imported from a .3ds file?

The error also occurs if a fit the grid to the full floor plan and try to analyze the grid on anything but the 0' z plane. However, I have been able to run the 3d grid analysis from 0'-22' within the large square space and it has worked.

This is the first time I have ever used Ecotect and am just trying to figure out as much as possible (so there is a chance I just did something stupid to cause this error without knowing, but I have been reading through the "help' menu and FAQ's on the website as much as I can to try and do things right.

Also I have a few more random questions that I have been struggling to resolve and find out answers for:

1. for my model the imported windows have 2 glass planes because of the way they are constructed in ArchiCAD. does this mean that ecotect will literally read them as being to surfaces with, lets say 92% transparency, meaning that only that 84% of the light actually gets through (.92 for first plane x .92 for second glass plane). Because that really matter when you have something that is less transparent....80% gets all the way down to 64% and so on. Is there a way around this or what should one do to avoid this problem?

2. Is it better to actually build the Ecotect model in Ecotect and do so as simple as possible (and in zones) for trying to figure out lighting and then making changes to get the ideal levels for your building. Then come back later and import the .3ds file from ArchiCAD in order to do renderings in Radiance. I guess I am just trying to figure out the most effective way to use Ecotect for future projects and uses so any suggestions from your experiences would be nice.

3. I am still confused how much the internal and external reflections effect the lighting levels. Are the values more accurate based on the color that you have for the material or the properties that you have listed for the material in the library? Also, are there any typical values that you can use to get accurate results? Likewise, does Radiance take this info from Ecotect to determine this kind of stuff if you do a "Lighting Analysis using Radiance".

Sorry for the many questions,

Kellen