I’m testing out a generic extraction of curtain wall grid cells from Revit into Grasshopper and am getting some strange results. For some reason, the orientation of the cells along the bottom level is what I would expect. Let’s call the cell points P. Along the bottom row of cells, P[0] and P[1] are the two bottom points. Let’s call P[0] the bottom right and P[1] the bottom left. But for all of the rows above the bottom row, P[0] is now the bottom left and P[1] is now the upper left. So basically all of the upper rows have the points shifted by 1.
What would cause the cells to be organized that? Is there a way to force Revit to provide a list of points for each cell that is consistent? Diagram below shows a vector going from the first edge of each cell to the third edge of each cell.
Oddly enough, I just discovered that the Planarized Cells coming out of the Analyze Curtain Grid Cell component actually are organized properly. So strange that they are rotated for the Curve output of the same component. Is this a bug?
How about getting the Orientation from the Analyze Panel component?
https://www.rhino3d.com/inside/revit/beta/guides/revit-curtainwalls#analyzing-panels
Ehsan, thanks, I had not seen that orientation output for the Analyze Curtain Wall component. However, it doesn’t actually answer the question why there would be a difference in the orientation of the cell and its panel. First of all, it seems like all of the cells should be orientated in the same direction as noting was done to them in Revit that would cause the first row to be different than the upper rows. Second, doesn’t it seems strange that the orientation of the cell and its panel would be different?
I would prefer to use the Curtain Wall Grid Cells as they don’t already have the offsets of the panel. But the Cells have messed up orientations.
Edit: I guess I mean why are the orientations of the “CurtainWallGrid Cell Curves” and the “CurtainWallGrid Cell Planarized Curves” (which seem to be also the panels), different?
It has something to do with the way Revit builds the curtain wall, probably in its treatment of mullions (boundary and interior differently), when you extract the grid lines it starts at the first row in, not the boundary.
Not know ultimate goal and workflow I would say the Panel origin point and normal are going to be your most consistent extraction.
So strange. Why is it so hard for Revit to even do the simplest thing (a grid) without weirdness like this? I’ve been trying to work backwards from the panels to get to the simple grid but even that is difficult as the mullion dimensions aren’t the easiest to extract in a consistent way.
That has always been my issue with Autodesk products, they will do 90-95% of what you want, the last % is always a workaround of some sort, and never addressed in further releases. That’s where rhino comes in to fill that gap; they respond to requests, innovate and at least try.