CRDSS_Task1_05-16_GeneralMapDisplays

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the database tables. This low-level library will be called extensively by the database display library, discussed below. The process of converting data between ARC/INFO and GRASS is well documented and is done frequently. There are utilities available in both ARC/INFO and GRASS allowing the transfer of data to be standard practice in applications (see Task Memorandum 1.06-2). It is envisioned that the general map tool will be used in the CRDSS as a spatial display tool that could provide a link to other types of data (physical characteristics, time series, structures, etc.). These types of queries will allow the user to select icons placed on the map in the locations of the data collection sites. These icons will have identification numbers specified in the INFORMIX database. Embedded Structured Query Language (ESQL) statements in the interface, as supplied by the low-level DMI routine library, will be used to communicate with the database. The database display library will consist of standardized forms (widgets) that are used to display database information and will consist primarily of Motif code. For example, a widget will be developed to display diversion structure information. It is anticipated that this information will consist of mainly tabular information such as location, description, important dates, capacity, etc. To be flexible, such forms will have the capability to step through a number of data items, e.g., to show all diversion details within a given area. Because each of the tables in the database contains specific information, there could be a display form for each table in the database that corresponds to a physical feature on the GIS display. In order to make the routines in this library reusable, limitations on the extent of the routines will be made. In other words, each display routine cannot lead to all other routines in a circular fashion. For example, displaying a structure could lead to the display of the time series for that structure, which could lead to the display of other time series, which could lead to physical characteristics of a gage.... Such circularity leads to confusing logic and a cluttered display. One feature that must be studied is that of time series plotting. A general tool for time-series displays will be available (see Task Memorandum 1.05-18); however, the access to such times series will need to be studied because these data will be a large part of the database. It is currently unclear whether a database display widget, such as a diversion structure form, should allow the time series for that diversion to be pulled up, or whether the entry point to time series should be through time series tools. This is not an issue if the only time series to be displayed on the same plot are the time series for a selected structure. More complexity can be added in Year 2. It is suggested that a switch be made available in these routines indicating whether information is editable or static so that these same routines can be used in the DMI utilities when generating scenario data (see Task Memoranda 1.05-8 and 1.05-9). The user will not be able to edit historical data other than to represent the change as a scenario. The components of the display tool will communicate as shown in Figure 1. The user will select items to be displayed by toggling overlay buttons (upper right in figure). For example, if cities are to be shown, then the "Cities" overlay button will be pressed. Pressing the button again will remove the cities from the display. The information for the display will be GIS GRASS data and/or information from the tabular database (the GEOLOC table in the CRDSS database will contain lat/long information for structures and may be queried in cases where such information is more easily or more rapidly accessed from the relational database), and will be retrieved using the GIS library. The GIS library will also contain routines to display legends, to determine and display mouse location, 2 A275 05.10.94 1.05-16 Malers