Multiple shadows in same view (Existing vs Proposed)

[bstrauss353542]

Hey guys, does anyone have any recommendations for showing shadows from different phases of the project in 1 view (eg. existing vs proposed). They need to be individually graphically distinguishable. Currently our users have the tedious task of tracing the existing shadows using a filled region and turning on the proposed shadows. For a large project, this can be a substantial investment of time.

Cheers,

Brad

[CAtDiva]

Use Photoshop to overlay the two?

[MikeJarosz]

Interesting topic for discussion. AutoCAD and Revit treat shadows as transient presentation graphics. Another CAD program I used years ago actually created shadows as polygons. They could be saved and manipulated. As polygons, their area could be calculated. That would help you out. Generate shadows for one setting and save them. Repeat with another setting, then combine.

Another use we found for shadow areas was in cities where the shadow a building casts is regulated. We modeled the whole NYC Central Park West skyline and cast its shadow on Central Park and calculated the shadow area. Then we added our proposed building and calculated the difference.

I have found over the years that learning multiple computer systems provides valuable insights into the shortcomings of other software. I never understood why Acad couldn't have a snap to 0,0,0. My other system had that snap, and 20 more. That seemed so basic. It comes under the heading "How do you know what you don't know"

[nhatzi]

we use the trace method as well, prefer not to take it out of revit.

[CAtDiva]

Here's another thought: rather than trying to have both shadows in one view, have them in two views (one for each condition), then overlay them together on a sheet.

[damon.sidel]

Use Photoshop to overlay the two?

I'm with CAtDiva: Not only would it be easy in Photoshop (or another image editing software), but you have all sorts of options with adjusting the shadow colors (blue for existing, orange for proposed, or whatever) and layer styles like multiply or overlay. Then you could really control the legibility of them.

Alternately, you could consider either a custom add-in or running it through another program like Rhino with it's wealth of plugins. Create 3d geometry to reimport to Revit. Perhaps a lot of up-front cost the first few times, but it could be an awesome pay-off later. With a custom tool you could have all sorts of cool output: multiple times of day/year, animations, etc. I imagine this is a for a presentation and therefore a method to make an argument. Imagine the impact you could have with some simple animations showing animated overlays for the solstices and equinoxes of existing vs. proposed.

Here's one example I found very quickly: http://www.grasshopper3d.com/video/shaded-and-unshaded-surfaces Obviously this is overly simplistic, but it's just an illustration of the potential.