Robins's Visual Chart Form Tips
TMG to VCF
This page created 1 Sep 2014
Hosted by Terry's TMG Tips
This article describes how VCF draws a chart using TMG data. It does not discuss the creation of the .RPT file that is created from Chart Options or if it has not been saved as the first action when the user clicks [Create Chart].
The sequence of actions is roughly:
- TMG reads the in memory version of the chart configuration .RPT file
- TMG writes a file with extension .VCC (VCF Command file) to location known by VCF. This file provides the settings for the next chart. The file name depends on the type of chart to be produced.
- Once that .VCC file has been written, TMG opens the VCF application in a special way.
- VCF recognises this as a request to create a chart and reads the .VCC file.
- VCF then makes requests to the TMG project files via many requests to GenBridge.
- GenBridge interrogates the TMG project files to retrieve the required data and sends it back to VCF.
- Finally, VCF lays out the chart on its screen.
- A chart can only be composed using data that GenBridge has the capability to retrieve.
- Editing a chart does not edit the TMG project. (GenBridge is a read only facility.)
- The construction on the chart is not updated if the TMG project is edited later.
- There seems to be no limit in the size of chart that VCF can produce. (320ft has been recorded).
- VCF gives very few errors when the data it has been provided has errors like circular links. It just doesn’t finish or crashes out.
- Creating and editing large charts on machines with smaller memory capacity can take a long while.
by Robin Lamacraft