BrSema4Sigs: British Upper Quadrant Semaphores for BVE4

Release 08.06

By Simon Gathercole
Date of issue 08/06/05

Introduction

Thank you for downloading British Upper Quadrant Semaphores for BVE4.  The files have been installed to Program Files\BVE\Railway\Object\BrSema4Sigs and this guide can be found there should you want to read it again.  The package contains working BVE4 signal objects representing the standard British upper quadrant signal arms installed from the mid 1920s onwards and still in use on some lines today. 

Driving with semaphore signals

For a good description of British semaphore signaling, see The Signal Box. 

BrSema4Sigs provides developers with arms to suit different light levels.  Note that arms for daylight use do not show the signal lamp illuminated: as a result, you may find that seeing the signal aspect is harder than with colour light signals - this is prototypical!

If you are a BVE4 user and have installed routes that require this signal pack, you may now run them.  You need take no further action:  the rest of this guide is aimed at route developers.

Copyright and use

This package is intended to be used freely in BVE4 routes.

You may:

You must not:

Package contents

Note

The package is in continuous development and further varieties will be added in future releases.

Signal Arms

Arms are provided for two light levels:
The 'low light' signals use the emissive brightness feature of DirectX format objects to produce a realistic bright signal lamp and are suitable for ambient light levels between about 140 and 200. Appropriate BVE 'glow' objects are provided to assist sighting (daylight signals should be used with the null glow object which provides no assistance at all :-).

Full size signals:

stop_arm_d.x
 stop ('home') arm (daytime)
stop_arm_l.x stop ('home') arm (low light)
dist_arm_d.x
 distant arm (daytime)
dist_arm_l.x distant arm (low light)

Miniature arms:

mini_arm_d.x
 miniature stop arm (daytime)
mini_arm_l.x miniature stop arm (low light)

These are miniature versions of the stop arm and are sometimes used to signal routes along goods lines or into sidings.

Shunt arms

shunt_arm_d.x
 shunt arm (daytime)
shunt_arm_l.x shunt arm (low light)

Shunt arms are striped horizontally and are used for 'calling on' 'shunt ahead' and 'warning' signals.

Glow objects:

glownull.x
 null glow object for daylight signals
glow_stop.x glow object for low light, stop miniature and shunt signals
glow_dist.x glow object for low light distant signals

Posts

(in the subfolder posts\tub)

post_21.x
 LM style 21' tubular steel post
post_21_tc.x LM style 21' tubular steel post with track circuit diamond plate
post_24.x LM style 24' tubular steel post for single arm
post_24_tc.x LM style 24' tubular steel post with track circuit diamond plate for single arm
post_24_tc_sl.x LM style 24' tubular steel post with track circuit diamond plate for 'slotted' stop and distant arms

All posts have ladders and a representation of the appropriate type of balance weight.

Miscellaneous

lamp.x
 lamp with bracket and signal arm pivot

Using the signals in a route

Declaring the signal arms

Add the following code to your route files, at the end of the With Structure section:

Signal(0).Load BrSema4Sigs\stop_arm_d; BrSema4Sigs\glownull;    ;; use the appropriate glow
Signal(1).Load BrSema4Sigs\dist_arm_d; BrSema4Sigs\glownull;    ;;  (see above)
Signal(2).Load BrSema4Sigs\mini_arm_d; BrSema4Sigs\glownull;

Note - if you are also using the BrSigs colour light signal package in your route, you will need to adjust the index numbers in the above list to avoid conflicts.  BrSigs currently contains 19 different signal types, so the indices would become:

Signal(20).Load BrSema4Sigs\stop_arm_d; BrSema4Sigs\glownull;
Signal(21).Load BrSema4Sigs\dist_arm_d; BrSema4Sigs\glownull;
Signal(22).Load BrSema4Sigs\mini_arm_d; BrSema4Sigs\glownull;

Inserting signals in the route

Stop signal

For a solitary stop signal, marking the entry to a section, at say 6000m in your route, add the following code to the With Track section:

6000,  .SigF 0;1;x;y, .Section 0; 4,

where x and y are the coordinates of the signal arm pivot.  x is normally -2.3, but the value of y depends upon the post used.  See later in this guide for the correct values to use with the posts supplied with BrSema4Sigs.  The index of the signal arm is 0 here but would be 20 if BrSigs were also being used.

The .Section command tells BVE which signal aspects to use when then next section is occupied, the one after that and so on.  To avoid confusion, BrSema4Sigs uses the same aspect numbers as BrSigs, here:

0
 danger (=red in BrSigs)
4
 clear (=green in BrSigs)

Distant signal

The distant signal for the above stop signal should be placed a suitable distance before it, to allow drivers time to brake:

5000,  .SigF 1;1;x;y,

where x and y are again the coordinates of the signal arm pivot. Notice that there is no .Section command: the distant is controlled by the same section as the stop signal. The index of the signal arm is 1 here but would be 21 if BrSigs were also being used.

'Slotted' distant signal

A 'slotted' distant signal is used when a section is so short that the distant must be placed on the same post as the preceding section signal.  The two arms are  controlled from different signal boxes, but interlocking located on the signal post ensures that the distant may not be cleared unless the stop arm is also clear.  The situation in BVE is thus a little more complicated:

8500,     .SigF 1;1;x;yd, .SigF 0;1;x;ys, .Section 0; 2; 4,

The first .Sigf is the distant and the second the stop signal: notice that they have different  values of the y coordinate.   Three aspects are needed:


 Distant
 Stop
 BrSigs equivalent
0
 caution
 danger
 red
2
 caution
 clear
 yellow
4
 clear
 clear
 green

Miniature arms

The code for a miniature arm is:

10500,  .SigF 2;1;x;y, .Section 0; 4,

The index of the signal arm is 2 here but would be 22 if BrSigs were also being used.

Miniature arms are used to protect entry to sidings and goods lines and are normally cleared only as the train has been slowed nearly to a stand.   This can be simulated in BVE using either a dummy station, or the .Pretrain command.

Using AWS with semaphores

AWS magnets should be fitted about 200m before distant signals only, except where a stop signal marks the end of an 'AWS gap' (a stretch of line to which AWS is not fitted).  This package does not include an AWS magnet object, but the one included in BrSigs is suitable and can be used in conjunction with the .beacon commands that interact with plugin-fitted BVE4 trains.

Declaring the beacon

To use the AWS magnet object from BrSigs, enter the following code following the With Structure section of your route file:

.Beacon(0) BrSigs\awsmagnet_1.x

Inserting beacons in your route

Insert the AWS beacon about 200m before a distant signal, e.g.

4800,  .Beacon 44000;1;1;0,

where 44000 is the code that identifies an AWS beacon to plugin-fitted BVE4 trains.

Using the other components

To build a complete signal from the components included in this package, you will need:
The lamp and the posts you wish to use should be declared and used as freeobjects.  The necessary coordinates are:

x coordinates

Enter the same x coordinate in the .Sigf command and in the .freeobj commands for the post and lamp: -2.3 is suitable for a lineside signal.

y coordinates

Place the signal post with a y coordinate of 0.  The arm and lamp should have the same y coordinate, which depends on the height of the post being used:

Post
 Upper arm
 Lower arm
21m
 6.39
 -
24m
 7.15
 5.32


This document © Simon Gathercole 2005

BrSigs is © Steve Green

Certain textures used by the post objects are © Anthony Bowden and used with permission.