edit shading transmittance?

[anthony75]

Hi
Does anyone here know how to give local shade objects an opacity?
I am doing a simulation on the effect of tree shade on thermal loading of buildings and need to edit the transmittance of my 'trees' to less than 0%.
I have treid modelling trees in sketchup as components and given them different opacities but this doesn't get carried through to VE. I also tried a test with single planes (modelled in VE) as local shade just to make sure i would notice subtle changes. I added windows with 90% transmittance to the shading planes but still no change in solar gain etc.
Any help would be appreciated.
Thanks

[anthony75]

just adding to the previous message...
I found a post on modelling trees but this is not the solution for me. I have collected tree data which includes three height, canopy size and transmittance. I have modelled the trees as 2 x 2D planes intersecting at right angles and hoped to just add a transmittance value to the planes. It seems like the most accurate way to translate the data I have. If there's a better way please let me know.
Thanks!

[ZapBran]

All obstructions are 100% opaque.
It's pants.