coordinate transformation

[darreng_oa]

i built a surface with points collected in a california state plane grid projection - survey feet, and now i simply wish convert to california state plane grid - meters. updating the drawing settings doesnt seem to convert.

any ideas?

thanks!

[wfberry]

I would try this.

Export your surface out to LandXML.  Start a new drawing using your California metric template set up for your locale.  Import LandXML into the new drawing.

Bill

[surveyor8120]

IF you have autocad map, you can set up a new drawing in meters and then query in the data from the us survey feet drawing.

[AllenJessup]

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@surveyor8120 wrote:

IF you have autocad map, you can set up a new drawing in meters and then query in the data from the us survey feet drawing.

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To do that you'd have to explode the surface or extract the 3D lines, do the query and rebuild the Surface from the lines. Map won't query Civil 3D objects.

Allen

[tcorey]

This is a good suggestion if the original data are AutoCAD objects but Civil 3D objects, such as Points, Surfaces and Alignments, do not query using Map.

For this poster, I would go with Bill's suggestion because I think the OP has COGO points.

If he doesn't want to start a new drawing, he could export his points to .txt, delete the points in the drawing, make a Point File Format for his state plane in feet, change drawing settings to metric, change coordinate system assigned to Ca state plane metric, import the points using the previously created point file format, be sure to turn on the option to Do coordinate transformation if possible, and rebuild the surface.

Best regards,

Tim

[AllenJessup]

I'd run the point file through Corpscon and rebuild the surface. Or if you built the Surface from a point file instead of Civil 3D points. You could just convert the points file.

Allen

[surveyor8120]

If you use a survey data base with Civil 3D, and if it is assigned a coordinate system in the settings.  When you have a drawing with a different coordinate system and you import the survey points and figures from a database it will convert the data to the drawing coordinate system.

[darreng_oa]

thank you for all the suggestions - my solution was to use corpscon, only because i did not have any TIN adjustments to make (and wanted to be certain transformations were dont correctly) but also thought that any sort of re-importing, data-shortcutting, etc would rebuild the surface as C3D sees fit, and ignore user-updates and changes made to triangles?  can anyone comment on the preservation of TIN line adjustments and coordinate transformation?

much thanks!

Darren