One of my users emailed me today. He only recently discovered the EXTARC command - basically found out a competing firm was using it. Well, he's processing a survey with a number of bridge piers. Shot as three points on the circumference, it seemed to be a perfect place to use the code. I've pasted the contents of the TDS RAW file that contains code for three piers.
Begin Raw File:
SP,PNAB1,N 490246.3600,E 1300436.8866,EL338.49,--TRAV
SP,PNPP11,N 490197.5914,E 1300370.9023,EL341.22,--PHOTO
OC,OPAB1,N 490246.36,E 1300436.8866,EL338.49,--TRAV
--HR:5.0 (5.0 + 0.0 Offset)
LS,HI5.26,HR5.0
BK,OPAB1,BPPP11,BS233.315562,BC0.0000
--Backsight HR:5.0 (5.0 + 0.0 Offset), Prism Const.:0.0mm
--Date: 10-16-2014 Time: 10:52:21
--BS check AB1 - PP11:ZE88.1705,SD82.083,HD err= -0.0044, VD err= -0.013028
--BS Circle check : angular err= 0.0000
LS,HI5.26,HR5.0
SS,OPAB1,FP1757,AR136.3134,ZE90.2705,SD249.247047,--PIER ST PC
SS,OPAB1,FP1758,AR136.1605,ZE90.3953,SD247.099024,--PIER
SS,OPAB1,FP1759,AR135.4942,ZE90.5245,SD248.453020,--PIER PT EXTARC
SS,OPAB1,FP1760,AR137.4252,ZE90.2841,SD239.304032,--PIER ST PC
SS,OPAB1,FP1761,AR137.2605,ZE90.4150,SD236.978027,--PIER
SS,OPAB1,FP1762,AR136.5818,ZE90.5050,SD237.957027,--PIER PT EXTARC
SS,OPAB1,FP1763,AR139.4941,ZE90.3346,SD222.266030,--PIER ST PC
SS,OPAB1,FP1764,AR139.3526,ZE90.4717,SD220.028018,--PIER
SS,OPAB1,FP1765,AR139.0443,ZE90.5553,SD221.076043,--PIER PT EXTARC
End of RAW file
What it is doing is drawing the circular figure but also drawing a line from PC to PT. Also, one of the figures fails to draw the full circular figure, drawing instead an arc from PC to PC with the in between point somewhere along the arc. And this figure also draws the closing line from PT back to PC. And, I found if I used one of the offset codes (+D, +H or +O) with a distance to offset, it does then draw the full circle but also continues to draw the line from PC to PT. I tested +D 1.0 and +D 0.1 which both worked, but +D 0.01 did nothing to fix the arc.
Sometime after this code was added to the software, I tested this and found it worked as expected. But we have moved on to newer software.
We use Power InRoads and PowerSurvey 8.11.07.615