# JMRI: RPS Tracking Frame

This frame displays a map of the RPS system's view of the layout.

## Display

There are two types of things drawn:

- The measured positions and paths of RPS transmitters
- The "detection regions" used for RPS blocks and sensors.

### Transmitter Positions

When a good position reading is made, it's drawn on the screen as a small circle representative of the measurement's accuracy. A line is drawn to this new position from the last position.

Different colors are assigned to different transmitters so you can tell them apart. If you "hover" the cursor over a point, a tooltip will pop up that shows you which transmitter was seen there and what position was measured.

Normally, bad measurements are just drawn as points, without connecting them to the next measurement via a line. They often carry very large position values, and will result in lines running off the panel. If you do want to see them connected, check the "Show error points" checkbox.

### Regions

JMRI can keep track of whether a region on the layout contains working RPS transmitters. This is used e.g. for the RPS sensors that are used to control signals.

These regions are displayed as blocks of color, possibly overlapping.

To get the exact coordinates of a region, hover the cursor over it. After a short time, a tooltip will display the coordinates of the corners.

## Controls

In the top part of the window are some simple controls.

- The "Clear" button erases the transmitter display, leaving the regions visible.
- The "Show error points" checkbox, mentioned above, will include lines to lower-quality measurements.
- "Show receivers", when checked, displays receiver locations as slightly larger black dots.
- "Show regions" controls whether the regions are drawn or not.

The four text boxes and "Set" button let you set the coordinate mapping for the window. The top two set the RPS position that corresponds to the upper-right corner of the display frame, while the lower two set the RPS position that corresponds to the lower left corner. The lower-left corner is often set to 0,0, and the upper left set to large enough values to show your entire layout, but you don't have to do it like that.