ORD - Changing Curve Radii is Moving Curve PIs/Geometry Edit Challenge

Question

I have a question on geometry edits in ORD 10.12.02.04 (2022R3). 
 I know that OpenRoads&rsquo; design intent and rules were intended to be timesavers. But I&rsquo;ve reached a point where &ndash; after trying to make extremely simple edits to a horizontal geometry &ndash; they are proving anything but. I freely admit user error is most likely to blame. What I&rsquo;m doing should take minutes. Yet I have not been able to accomplish the task in a couple hours. Are you up for a challenge? Try and make the edits I&rsquo;m requesting in this file and please tell me how to accomplish it. I&rsquo;ve viewed many videos on how to modify OpenRoads geometry to no avail. 
 The attached DGN has a single alignment, &ldquo;RampTest&rdquo;. It has all simple curves, no spirals. There are four curves; I&rsquo;m simply trying to modify the radii of the southerly two&hellip; and that&rsquo;s it! No moving PIs, nothing else. The southernmost curve with PI 13+15.92 - I&rsquo;ll call it Curve 1 - has a radius of 9046.7020&rsquo;, or 38 minutes. I want to modify it to be 9549.2966&rsquo;, or 36 minutes. The next curve to the north with current PI 27+47.75 &ndash; let&rsquo;s call it Curve 2 - has a radius of 6875.4935&rsquo;, or 50 minutes. I want to modify it to be 7473.3625&rsquo;, or 46 minutes. I want the ending station to be the same, so my start station will be 9+xx.xx. 
 I can readily modify the radius of Curve 2. Type in a new radius, it updates, great. But that&rsquo;s all I can do. 
 Curve 1? That&rsquo;s trickier since it&rsquo;s an arc at the end of an alignment. Back when, I&rsquo;d have added a PI off the geometry end, modified the radius, then deleted the additional tangent. There are PI-based commands in OpenRoads to create geometry, but not modify PIs (so far as I know). So, as holding the PI location means the curve will get flatter, I need to append the geometry off the south end so it can lengthen. And that I&rsquo;ve done a number of times, with a &ldquo;dumb&rdquo; regular line and also a geometry line created in OpenRoads. I&rsquo;ve tried to do so by snapping, and not snapping. Whatever the method to create the tangent, I then append the complex geometry with that line, then try to change the radius. When I do that, it doesn&rsquo;t simply change the radius of Curve 1. It also changes the PI location&hellip; the PI moves. What&rsquo;s really weird is that changing the radius of Curve 1 also moves the PI of not just Curve 1, but it also moves the PI of Curve *2* as well! 
 ??? 
 If I start by changing the radius of Curve 1 before doing anything else, it will still move *both* the PIs of Curves 1 and 2. 
 If there is a rule at play, I cannot figure it out, cannot disable it, and it&rsquo;s driving me crazy. 
 On a hunch, I created new geometry myself in this file, another test alignment. I was able to modify curve radii and not a single PI moved. 
 As far as I know, this geometry originally came from an SS2 ALG a while back (I'm not 100% sure and don't have access to that ALG). I have no desire to re-create the geometry. We have sheet cuts and a profile based on it already (the changes are very minor, to where modifying two named boundaries manually is not a big deal) so re-creating it would present other issues. 
 I want to like this program. Please, help me eat crow... tell me how make these edits. What am I doing wrong? 
 Thanks for any and all information! 
 RampTest.dgn

jcallicott · Accepted Answer

Thanks to all those who responded! This one proved tricky&hellip; but all the shared insight was a big help. Thanks to everyone for the information; I really appreciate it. 
 Using that information, I determined because the alignment end was on a curve, it could not have been defined as a fillet like the other curves. Even if I was able to extend the complex alignment on the correct tangent, the curve was still defined differently and thus difficult to edit. 
 What I wound up doing was deleting the curve and then redefining it. This was my solution process to modify the ending curve of the alignment: 
 
 Backup the alignment DGN. 
 Draw a (dumb) line - Line 1 - representing a tangent off the end of the curve. This is to have a tangent to refer to, since if the curve gets flatter the alignment must lengthen. It&rsquo;s not exact but is a best guess. 
 Mark the current curve PI by drawing another (dumb) line - Line 2 - from the current PI. 
 Under Modify --> Geometry Builder Edit, use the table editor to delete the end curve. 
 Deleting the ending curve moves the remaining geometry to the same start point. So, use the Transform command to move the remaining geometry back to the same location (usually by snapping to the *other* end point of the geometry). 
 Click on the complex alignment to get handles to appear. Then use the handle at the end of the tangent to move the end of that tangent to the end of Line 1. 
 Use the Modify --> Insert Fillet command on the newly extended tangent. For the vertex, I snapped to the end of Line 2. I specified the desired radius and completed the edit. 
 Line 1 was drawn as a best guess and was inevitably a little too long, so under Modify --> Geometry Builder Edit, use the table editor to delete the remaining tangent off the end of the new curve. 
 Similar to Step 5, deleting that ending tangent moves the remaining geometry to the same start point. So, use the Transform command once more to move the remaining geometry back to the intended location. I used the other end of the geometry this time too. 
 Under Modify --> start station, I reset my stationing so the stationing past the edit to the first curve remined the same. 
 
 It&rsquo;s a bit of a workaround, but it works. Thanks again for all the help and tips!

Mark Shamoun · Answer

Hi jcallicott, 
 
 In my opinion, ORDs biggest weakness on the design side of things is exactly what you are highlighting here - specifically the inability to redefine the way Geometric elements are connected to each other, hence your pain. Looking at the data, the reason curve 2 is so easy to edit is because it is defined as a fillet, which uses the connecting straights to define its incoming/outgoing bearing so adjustment is easy (and predicable). 
 
 The first curve is a bit less predicable to edit, something all users, including myself have issues with because it may have been defined many different ways - as an Arc Between Points or Arc to/from Element, and how was that Arc defined, by bearing/direction, center etc. This is what all of us spend a lot of time trying to figure out during editing. 
 
 Looking in the Alignment properties, the first arc is an Arc defined by Through Point, Sweep Angle and some other points. This being the case, the Tangent Points of the Arc will not move on radius change by default. To change this behaviour, select the PI manipulator, change the Placement Method to "Start/Radius", enter the radius you want and lock it and when the command is accepted it will retain the PI point and update the arc to the new radius. 
 
 Next, to extend the start, select the "Move Point" manipulator at the start of the arc and you will see it wont let you move it (for some reason). Change the placement method from "Center/Radius" to "Start/Radius" and it will let you extend it without changing the radius as long its value is still locked. 
 
 In most circumstances we just give up and recreate the curve and use the "Complex Redefine" command. Definitely some work needed here to avoid us having to be detectives to figure out how to manipulate geometry!

Shawn Cooke · Answer

A few notes to add here from what both Marks stated. In some cases, the Table Editor will simplify geometry and clean up rules. Once an alignment is designed, one way to quickly "rebuild" or correct a quirky alignment for easier manipulation is using the Import Horizontal Geometry from Ascii tool using the format below. (initial design report to help grab XY e.g. HorizontalElementsTable.xsl). This has worked to clean up PRC, PCC, etc. in rather complex designs that wouldn't open in the Table Editor or modify easily. I've had people combine so many random methods and various tools in building an alignment that the Table Editor didn't recognize!

ORD - Changing Curve Radii is Moving Curve PIs/Geometry Edit Challenge

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