Copied from the original development topic.
diamond-crossing is one where the V-crossing angle is the same at both ends. This also means that both roads are straight, or both curved in the same direction to the same radius.
In a regular diamond-crossing the angle of the K-crossings at the centre is the same as the angle of the V-crossings at the ends.
(Regular diamond-crossings have been supported in Templot since version 077 of September 2002.)
diamond-crossing is one where the V-crossing angles differ. This also means that the radius in each road is different. The most common application for an irregular diamond-crossing is in a double junction, where the diverging route is curved across the junction, and the main route is straight, or less curved, or curved in the opposite direction.
In an irregular diamond-crossing the angle of the K-crossings at the centre differs from the angles of the V-crossings, and there may also be a a very small angle difference between the two K-crossings.
Irregular diamond-crossings are now fully supported in Templot2.
There are 3 ways to create an irregular diamond-crossing:
Start with a regular half-diamond template.
Change the K-crossing angle using F10
mouse action and/or change the V-crossing angle using F9
In most cases change also to a curviform
type of V-crossing -- real > V-crossing options > curviform V-crossing
menu item. (For this method this setting is optional.)
Click the tools > make diamond-crossing
If the angles differ, the result will be an irregular diamond crossing.
If the angles are the same, the result will be a regular diamond-crossing.
Start with a turnout
having a curviform
Click the tools > make ladder crossover > make curviform ladder
Click it again a few more times.
The above two methods can cope with having a transition curve in the main road, although you will probably need to follow up with some adjustments to the transition zone to get the desired result.
Start with two lengths of curved plain track crossing over each other, or one curved and one straight length. One should be a background template and the other the control template.
Click on the background
On its menu, click peg/align tools > make diamond-crossing at intersection
Follow the instructions and wait a moment while Templot does the calculations.
You will then need to split the underlying original background template and shorten each half back accordingly.
The method doesn't work for transition curves, it is for straights and fixed-radius curves only. Also it is very easy when testing to have the tracks crossing at too short an angle. Templot can't produce crossings shorter than 1: 1.5 RAM ( i.e. not more than 33.7 degrees).
This method also works for two straight tracks intersecting, but in that case the result is a regular diamond-crossing.
For all irregular diamonds you will probably want to do some timber shoving to tidy them up.
Note that the DP
peg position (CTRL-3
) for an irregular half-diamond is not coincident with central CTRL-0
position and serves little practical purpose. Or at least, I haven't found a use for it yet.
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