★ APPLICATIONS ★ CREATION GRAPHIQUE ★ SPRITE DESIGNER (SETANTA SOFTWARE)|Amtix) ★ |
| Sprite Designer (Setanta Software) | Applications Creation Graphique |
NOT MUCH LIFE IN THIS SPRITE Our new technical editor, ANTHONY CLARKE, makes a detailed investigation of Setanta's Sprite Designer Setanta Software have in the past given us some pretty useless software and the ‘new' Sprite Designer is no exception. Once I had loaded the tape version after a frustrating hour I had a sense of deja-vu and readily used the package without even reading the instructions. This seemed a little strange at first but a quick jaunt around my magazine archives revealed that the Sprite Designer and program were straight from the November issue of a magazine. I assume Setanta had permission to do this. That aside the package features a full sprite designer, various assorted scrolling commands, a FILL command and some fairly useless box, triangle and circle commands. It is not easy to start using the commands, as you must first load the Sprite Designer and then tell it to save the sprites which will also save the commands in a form that can be loaded directly, the sprites being saved along with the machine code, which sets up and executes the RSX's. The FRAME command is used to make animation and scrolling smoother, but waiting for the FRAME FLYBACK which, simply put, is the time when the electron guns track back across the screen from the bottom right to the top left. Any screen operations taking place at this time will not be visible until the screen updates and so can stop the flickering that is associated with many sprite routines. The addition of this command is, however, not needed as calling &BD19 will have the same effect and take less time as the call command does not need to be looked up in an RSX table first. SCROLLING TO LEFT LSCROLL scrolls text lines to the left, wrapping the characters around the screen, ie, any characters going off the left hand side will be placed on the right hand side of the display. Instead of specifying a range of lines as with many scroll routines you must instead specify all the lines you wish to scroll, so if the whole screen is to be scrolled then you must perform the laborious process of typing 25 parameters. RSCROLL works in much the same way as LSCROLL but the scroll and wrap around are performed on the the right. USCROLL scrolls the whole screen up but has no provision for scrolling individual lines of text so using it to right some sort of SPY HUNTER game is impossible as any status line would be lost. DSCROLL scrolls the screen down and suffers from the same problem. If you wish only to scroll a 'WINDOW' of text one byte left or right the the WRAPL and WRAPR commands can be used. The left and right columns must be specified along with the text row, unfortunately only one text line can be specified at a time so scrolling a window of more than one line will take more than one WRAPx command and therefore longer to perform. EXITR and EXITL take the same parameters as WRAPL and WRAPR but do not wrap the screen, instead any data scrolling off one side of the screen is lost. The LARGE command allows the expansion of anything found on the text rows specified and so can be used to make any text or graphics double height, very useful for headings. The extended graphics commands include CIRCLE, TRIANGLE, BOX, FULLBOX and FILL commands. The CIRCLE command has the same syntax as the Spectrum's CIRCLE command with addition of a parameter specifying the colour of the circle. The X and Y positions of the centre of the circle must be specified. BOX and FULLBOX both seem quite useless and are only included to fill out the package. Both require 5 parameter, the bottom left, top right corners followed by the pen to draw the box in, BOX draws only a skeleton frame where as FULLBOX floods the entire box with the specified ink. TRIANG draws a wire triangle and requires the position of all three points and the pen colour, experimentation showed a that the the points must be specified in the order lower left, lower right, upper point or the effect could be disas-terous. ONE USEFUL COMMAND FILL is really the only useful command, and then only to a 464 owner, but tended to leave areas unfilled as it did not keep a note of areas that were missed as the fill command on the 664/6128 does. Now we come to real reason for the package, the sprite commands, of which there are only two, SPRITEON,x,y,n and SPRITEOFF,n, x and y specify the top left hand corner of the sprite and n the sprite number. The x and y parameters are not required in the SPRITEOFF command as these are remembered by the program. The sprites do not destroy or XOR with the background but instead remove do a complete swop with the sprite in memory. This means that if your sprite has a large area unused within itself then this area shows up a large back area on the screen, it is my opinion that XOR's are a much better bet than the this primitive form of sprite command. To make things worse the sprites can only be used in mode 0, multicolour mode, and can only have a size of 16 by 16 pixels, so all sprites are twice as long as they are high, surely a system of multisized sprites could have been programmed in with little difficulty. The Sprite Designer has only 6 commands. C clears the current designer grid, I sets a specified pen to a new ink or pair of inks, P selects a new pen, N selects a new / old sprite grid to be edited, G loads and saves sprite grids and S saves the sprites and commands to tape or disc. The G command does not save sprites in a usable form but as information about each cell in the grids to be saved. Once again I think Setanta have wasted time and money on another turkey, my advise is to save your pennies and buy Laser Basic.
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