Eye-catching horizontal display
Text Sidewinder displays your text as a horizontal banner flowing across the screen. You can use it as a stand-alone or insert it into your own programs. This short BASIC program works on all 8-bit Atari computers of any memory size, with disk or cassette.
If you ever wanted to program an eye-catching horizontally scrolling video text display for a user's group booth or in-store use, Text Sidewinder should be just the thing for you. This program floats a multi-colored message across the screen-as much as 2,500 characters long. Experienced BASIC programmers can easily convert Text Side-Winder into a subroutine for their own larger programs.
The SideWinder display can be in either Graphics 0 for standard-size characters, Graphics 1 for double-sized characters, or Graphics 2 for even larger characters. The program takes your message-entered as DATA statements at the bottom of your program-and places it into a long character string, which it then slides across your screen.
USING THE PROGRAM
Type in Listing 1, SCROLLER.BAS check it with TYPO II and SAVE a copy before you RUN it.
The banner's speed is displayed in a window on the screen. Lines 50 to 60 contain the timing loop that controls this speed. Pressing the Space-bar gradually cycles the banner speed to a peak of 10 and then resets it back to 150. If a steady speed is what you want, delete lines 55-60 and change line 50 to:
50 FOR R=0 to TIME:NEXT R:RETURN.
In line 630, "TIME=150" can be varied to change the default speed setting. The routine which displays the banner is in lines 1000 to 1020.
DATA statement lines 4000 to 4010 contain your message. If you follow the rules below, you can type in your own words and change the colors.
In Graphics 1 or 2, upper case letters (capitals) in the DATA statements show up orange, and lower case becomes green. Upper case/inverse is blue and lower case/inverse becomes pink. These are the default color settings in those graphics modes. To experiment with different colors, try typing commands such as SET-COLOR 2,3,4. (For the SETCOLOR chart showing all 128 available default colors in the graphics modes, see Chapter 8 of Lon Poole's book, Your Atari Computer, $17.95 from Osborne/McGraw-Hill Berkeley -ANTIC ED)
No commas should be used to separate text in the DATA statements. In order to show up properly on the screen, words should be split at the end of each DATA statement. Spaces cannot be added at the beginning or end of DATA statements. To understand this format better, observe how the sample text is handled in lines 4000-4010.
Jess Engelhart lives in London, Ontario, and is currently working on a communications program for the handicapped, featuring the Covox Voice Master.
Listing 1: SIDEWIND.BAS Download