how to do coordinate transformation or conversion between two local drawing.(two no projection drawing
how can i do the above in civil 3d
It's been many years (thank God!) since I had to do this, but if neither survey is in a world-based coordinate system, you are probalby going to have to find a couple of common points between the two and do an old-fashioned 'translate and rotate' (AKA move and rotate) routine to line them up. If you start with a clean drawing, then bring in both surveys as blocks, you can move one of the surveys as a block to get it lined up with the other before exploding both.
Last time I needed to do this, I had three legacy surveys that were done in local coordinates and none of them pointed to true North. One of them actually had survey North pointed to the South-West! I kid you not.
The only other way I can think of to do it is to go back to the surveyor(s) and have them re-compile the survey data to a state-plane coordinate system. Our survey requirements now call for a state-plane system or WGS to be used on all surveys.
If you're using a survey database, right click on the name of the database in the survey tab of your toolspace and select translate database. This will translate (move and rotate) everything in the database as well as changing the vertical datum if you need. You can select the common points in the two drawings and get them lined up however you want.
The few replies you'e gotten are good. But some more information from you would cement which course of action you need to take.
for example i want to transform the survey database (JOEL SLAB) to (GEOTEX) because that is the general coordinate sys we are working with,
am having challenge to do it. i could not find the outcome, especially the point 01(that was written with blue color)i want to put it to my main database
thanks
If you know the "new" coordinates of two points in your existing DB, then the attached PDF should help you.
Don Ireland
Engineering Design Technician