CRASH - The Online Edition
— Issue 6 Contents|
Utilities galore! From screen creators to moving graphics, a multitude of aids are available to help the budding programmer along. Anirog’s SPECGRAF is in aid of the User Defined Graphics manipulators, UDGuys for short. The program allows you to hold up to 200 UDGs in memory at any one time. Up to nine UDGs can be edited on screen simultaneously. Let’s take a look at this latest UDG fast breeder.
The cassette, which is contained in a neatly packaged plastic case, contains SPECGRAF, the UDG creator on one side and Roller, a demonstration program, followed by Toolkit, an assortment of subroutines for handling the UDGs on the other.
The main menu displays seven options. (1) VIEW WHOLE SET displays the current UDG set containing 20 characters from A to T. The current UDG set can be selected with (4) CHANGE SET from any of the 10 sets. (7) PRINT BYTE VALUES will list the bytes of the set in hexadecimal or decimal form in two pages with the possibility of a hard copy. (2) SAVE SET TO TAPE and (3) LOAD SET FROM TAPE involve the storage and retrieval of the UDG sets. A name can be given to the tape file, which can either contain a single set or the complete repertory of UDGs. These sets can be loaded for future editing or for serious use into any of the sets from 0 to 9. (6) EXIT provides an exit facility from the utility. Run returns you to the facility. (5) DEFINE CHARACTERS leads to the central activity of the program, namely the editing of the UDGs.
The FORMAT MENU makes available nine different formats. This enables up to nine UDGs to be edited in the format in which they will appear in the program for which they are being designed (from 1 to 3 x 3 characters). The program requires an input of the first character to be defined. The group of characters required for the chosen format must be consecutive and within the same set. Next you are asked for the set required. If existing characters are to be edited, the set in which they are held must be entered.
The screen will display the grid in the format selected. Grids of forms with more than one character indicate the individual character areas with white and yellow backgrounds. The existing characters will be copied to the grid and a miniature screen in the top right. A flashing cursor may be controlled via the cursor keys or the Kempston joystick. The current start character is indicated at the bottom right of the screen.
The options available are displayed on the right-hand side of the screen.
Once created and saved to tape, the UDGs require handling from within a Basic program. Roller demonstrates the use of two sets of graphics and by breaking into the program illustrates all the points required to use SPECGRAF UDGs in your own program. The routines used are contained in Toolkit which follows Roller on the tape. The 200 UDGs may be used either by paging between 10 sets of 20 UDGs or, alternatively, by displaying 96 different characters by poking the system variable CHARS with 256 less than the starting address of your graphics. This will redefine the characters from space to the copyright symbol with the SPECGRAF characters.
The SPECGRAF is a useful and dependable tool for creating User Defined Graphics. Considering the amount of facilities it provides, the price of £9.95 may prove to be a little high in view of the stiff competition such as Procom’s DYNAMIC GRAPHICS with its excellent moving sprite facility or Print ’n’ Plotters PAINTBOX with its integrated screen creator. SPECGRAF certainly performs well and should ensure that you don’t run out of UDGs any more.