Work with irregular lines

Irregular lines are a bit of a hassle but can be dealt with relatively easily once you have an understanding of what needs to be done.

Beware, irregular lines extracted from Landonline are doubled up as the line is part of 2 parcels (one each side). To avoid problems turn off all the irregular layers and only turn on only the ones you want.

Marks on an imported irregular line from Landonline always start with an "i", keep this in mind, it is important. either end of the irregular line must be a whole number ie "7"

Below are some guidelines for the most common issues to do with irregular lines.

No editing required.

The easiest way is if you can leave the irregular line as it was extracted from Landonline. Make sure you have turned off the unwanted irregular line layers as discussed above. Define your parcels as you would normally.

Intersect existing irregular line.

To intersect with an irregular line extracted from Landonline use 'Graphical Tools' within SDR to intersect the new boundary line with the irregular line, this will create a new point. DO NOT connect a new boundary line to a point on an existing line (with a name starting with "i") it needs to go to a integer point number. Define your parcels as you would normally.

Alter an existing irregular line.

You can move the irregular line marks imported from Landonline to wherever you want, just remember that all marks in an irregular line must begin with an "i", if you add a mark make sure it starts with an "i".

Not in Landonline at all.

If an Irregular line doesn't exist in Landonline you can either add marks in SDR or do it in CAD then import them into SDR, just make sure the mark name starts with an "i". You may need to copy marks in the 'data editing' menu of SDR, renaming the marks with an "i" in front.

Cheats Method

The reality is LOL often seems to stuff up an irregular line that has been imported, another method is to add a straight line in SDR in place of the irreg line then add the irreg line in LOL after deleting the bogus obs.

Work with curved boundaries

Curves are much easier to deal with than irregular lines. Export parcels from SDR in the same way as you would have for a normal parcel. When you import data into SDRTransfer you will see that on the observations page you will have some data in the arcs tab at the bottom.

At the top of the arcs tab you will see an area where you can enter the arc centre, radius and rotation direction of the arc. Be careful entering the centre point, put one space between the northing and the easting. The rot is the rotation direction of the arc, CW (clockwise) is to the right as you look along the arc.

You will need to enter the chord Azimuth directly in the datagrid. The update button is used to display the arc on the screen. The display is not working yet , however the data will still be output correctly when you export to Landonline.

Edit Observation Topology (what parcel the obs belongs to)

enter edit mode, to do this go to the obs tab and select TOOLS > EDIT MODE. This allows you edit things you normally can't such as the from and to mark numbers, be careful.

Click on the observation you want to edit and click TOOLS > EDIT OBSERVATION TOPOLOGY.

The first box will show what parcels the observation is associated with, to remove these parcels tick the check box and click REMOVE. To add a parcel click add and check the parcels you wish to add.

Add new Observations

You must be in the edit mode - see above

Click TOOLS > ADD NEW OBSERVATION and select the start and end points, the new observation will be added to the bottom of the data grid and can be edited like an other observation. The bearing and distance as calc'd will need to be checked and edited if required.

Delete Observations

You must be in the edit mode - see above

only traverse observations can be deleted, to delete boundary observation you must re-assign the toplogy to another observation first, see above.

Select the observation from the data grid then select TOOLS > DELETE CURRENT OBSERVATION

Deal with mis-read observations from the SDR file

If you have a look at the traverse listing that comes from SDR you will notice that there is no way to easily determine what is a traverse listing and what is a pegging block. Sure the traverse listing normally has a misclose at the bottom, but not always.

SDRTransfer works out what is what by calculating a join between each set of coordinates and comparing that with the bearing and distance on each line. If it is a traverse block the join value will agree with the bearing and distance on each line, if it is a pegging block then they will not agree as the bearing and distance will be related to the top line of the block only. The tolerance used for this comparison is set in the OPTIONS page under "Trav Tolerance" for most situations 0.5 should be fine, however you may need a higher value if you are working over very bad work. You should make the tolerance larger than the misclose divided by the number of observations, ie if you have a misclose of 4.0m over 8 legs then the coords of each mark are adjusted and the difference between the obs and join value would be in the order of 0.5m, in this case you would need to up the tolerance. Don't make the tolerance too big as it could cause problems .