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Site Model Slope Analysis - how to list colored areas without tracing over


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I can't find a solution for this simple problem.

I use a Slope Analysis from a Site Model with 5 groups of different slopes each colored in different color. Having 5 colored slopes and not being able to tell the square footage areas for each group is quite disappointing. The workaround is to trace over in VW or use other program.

First method means that I use either 3D model top view or create a Snapshot and then in VW I trace over each colored zone. Very time-consuming task.

Second method means I need to use Photoshop or "Image J" programs with Threshold Color function to measure each layer area. But it requires applying a Scale 1 pixel = to whatever is scale in foot. The result is inaccurate.

So my question is:

Is there any direct way to retrieve data from Site Model Colored Slopes into a Worksheet?

Please help.

see attached example, a) site model with colored slopes, b) separate traced over in VW to calculate area and c) same layer in Photoshop to measure area

Edited by Ash
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Not a totally automated way, but this seems to work.

Take a Snapshot of the Site Model in 2D showing the slopes. Move it away from the model. Possibly off the page. Draw a Rectangle around the Snapshot. Go to the Data tab of the OIP and name the Rectangle "MyRect". Send the Rectangle to the back. Select the Snapshot and Ungroup it.

Create a Worksheet with a Database Row. Set the criteria to Type is Polygon and Location is "MyRect". Set Column A formula to =FB. Set the Column B formula to =Area.

Select the database header row (i.e. 2 not 2.1, 2.2 ...) Drag the SUM tile down to the Column 1 header.

You should now have a database with the number of different slope ranges and the total area for each slope range.

If you modify the Site Model, delete the group from above "MyRect", Move a new Snapshot over MyRect. Ungroup the Snapshot. Recalculate the worksheet.

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Thank you Patrick:

Very nice work, I really appreciate your help. Many many thanks, I owe you big time.

Please see attached, I wonder if there is a way to sort data in table, play with order of colors to match original table.

Maybe I can pull data from new table and show them in old table. Any other idea for criteria.

Is there a way to format "cell Pattern color" by assigning "FB index code"?

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The easiest way to do the sort would be to create an IF formula that would convert the FB color constants into a serial number. Something like:


But you will need to extend it to have all the categories you need. The 6 at the end is to handle situations that don't match any of the FB colors. This is the ELSE clause of the entire formula.

You will probably then need to drag a SUM tile to the column with the index formula so you will get the actual value instead of the total. You can then also drag one of the sort tiles to that row also so they will run in order.

I don't think there is any way to access a database subrow from outside the database, so you will have to change the old table to use the new way.

There is no way I know of to set the formatting of a database subrow different than the other subrows. Formatting seems to work on columns only.

One option would be to use the =Image function and create a small image file with each color that could then be displayed in a cell.

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Thank you.

Attached is final look of two tables.

My old table is used for final print. Data follows your method and auto calculated in the first table above, then I manually enter the same data into old table for print.

Last changes were:

1) Formula for Column Category:

=IF((B2=1289), '1', (IF((B2=1240), '2', (IF((B2=1290), '3', (IF((B2=1291), '4', (IF((B2=1237), '5', (IF((B2=257), '6', 'oops')))))))))))

2) Formula for Column Image (without SUM)


3) Format Column 'Image'

Format Cell - Images - 2D Attributes - Fixed Points

So far, I've learned that Site Model SnapShot can be UnGrouped. The Contour lines are separated. The total quantity of Polygons for Slopes in Triangulated Model was over 17,000. Every refresh of Worksheet took several minutes. So I decided to combine all polygons with the same color into one with Modify / "Add Surface" and then pay attention to total area, and if group is objects, not polygons, then carefully did conversion of few polylines into polygons. Final total polygons quantity became = 175, now much better and manageable.

I hope this will help other people.

Thanks to all forum users and special people like Pat Stanford.

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  • 8 months later...

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