Suggestion for an Atari presentation-program file-format called SLIDE

english translation by Andreas Magenheimer

Version 1.1, March/10th/2003


Whenever I am preparing a presentation for an Atari fair, like the ABBUC JHV (1) or Schreiersgruen (2), it annoys me to use a PC system and an application like Star Office or, even worse, M$ PowerPoint for the presentation. This should be possible with the Atari as well. Alas, up to date I haven`t really found a flexible presentation program for the A8. That`s why I made some thoughts about an Atari presentation format. This presentation format is independant of any implementation, e.g. it is possible that the presentation files can be read or shown by different presentation programs. For the creation of these presentation files one may also use a different program…

General Format:

The presentation files should be saved as pure ASCII / ATASCII files. Thus, it is possible to create these files with almost any text-editor (Compyshop-Text-Editor, Antic Writer, Analog`s T-Edit, Speedscript, Textpro, Action! Editor, Atari Writer, etc.) or with a special (external) presentation-creation-program. Pure text files can be read or written FROM any Atari programming language and exchanged easily between computers. Each line of the presentation file contains a statement which defines a) the contents or b) the style of the presentation.

Statements:

Each line of the presentation file starts with a four (4) character wirde statment, followed by a double colon (:) and the appropriate arguments for the statement. The statement ends at EOL (155, $9B). Example: Text: Welcome to Atari World 2084 Style-statements are active FROM the line they are defined, until a) they are re-defined or b) the end of the presentation.

Content-Statements, SLIDE Version 1.0:

VERS: version number, arguments: a number between one and 255, defines the SLIDE version. Presentation programs should ignore unknown statements, the version statement should be set at the beginning of the file.

TEXT: text, arguments: up to 40 characters. This statement prints on-screen text FROM the next line, while using all previous style-statements.

TITL: title, arguments: up to 20 characters, describe the title of the actual page.

PICT: picture, arguments: filename of a picture in uncompressed 7680 Bytes format. This picture will be shown instantly, if a common graphics screen (7,8,9,15) is active.

KOAL: picture in Koala/Micro-illustrator format, arguments: filename of a picture in compressed koala-format. This picture will be shown instantly if an graphics mode is active. It depens on the implementation if all compression options of the Koala-Format are supported.

TRAN: transition, arguments: filename of the transition-effect (see also paragraph about transition-effects).

REMK: remark, arguments: text with up to 80 characters. This statement is to comment the presentation.

Style-Statements, SLIDE-Version 1.0:

SIZE: text-size, arguments: number between 1 (normal/small) and 3 (big/large). The displaying-technique is left to the implementation (by displaylist-changes, fonts, graphic-text, char.-graphics, etc.).

ALGN: alignment, arguments: right, left, center, block. Alignment of the following/forthcoming text.

TCOL: textcolor, argument: color-value of the Atari palette of colors between 0 and 255.

BCOL: background-color, argument: color-value of the Atari palette of colors between 0 and 255.

EFCT: effect, arguments: ml-programs for page 6. The ML-program creates an effect while showing the page (text and/or graphic). The program should be a normal Atari DOS *.COM file, which loads INTO page 6 and initializes via a jump to 1536/$600. The ML-program should return to the main program by a keypress or via the joystick button/trigger. The program must be loadable FROM Basic (e.g. via the OPEN command), therefore it should process the values on the stack given by Basic. This statement should also be useable to play music.

BLIN: blend-in, argument: –. Call the blend-in routine at memory-location $603.

BLOT: blend-out, argument: –. Call the blend-out routine at memory location $0600.

WAIT: wait, argument: 0-255. This statement stops the presentation for 0-255 seconds.

PAUS: pause, argument:–. This statement stops the presentation and waits for a keypress or the fire button/trigger of Joystick number one.

SCRL: scroll, argument: 0-255. This statement shows the following/forthcoming text-statement as a horizontal scoller. The argument 0-255 sets the speed of the scroller / scrolling (0 = fast, 255 = very slow).

GRAP: graphics, argument: valid atari grahics mode. Chooses the Atari graphics mode

FONT: font, argument: filename of an Atari font (1024 bytes). This font will be loaded and activated.

Transitions:

The statement TRAN loads a ML-program INTO page 6 (1536, $0600). This program creates a transition between two slides. The program has two init-adresses:
1. $0600 / 1536 blend-out (fade-out)
2. $0603 / 1539 blend-in (fade-in)
The presentation-program loads the transition-effect. Therefore one should make proof, if the program for the effect is still in memory to avoid any unnescessary loading process. The statement BLOT calls the transition-effect and the blend-out-vector. At the end of the blend-out-effect (fade-out-effect) the screen should be switched to black, by switching off the Antic DMA. The transition-effect program gives the program execution back to the calling program (the main program).

The presentation program now sets up the new page. This will not be shown, since Antic DMA is still off. The statement BLIN calls the transition-effect blend-in-vector. The blend-in-effect (fade-in-effect) should first activate the Antic DMA and then SHOW the blend-in-effect. The blend-in and blend-out routines should also be called FROM Atari Basic, e.g. the routines must take care of the values put on the stack by Basic.

If the presentation-program is written/coded in ML or via a Compiler (CC65, Action!, Quick), one should simulate the Basic call-conventions.

Carsten Strotmann, March 2003.
with imput from
Mirko Sobe
Andreas Magenheimer

Please send comments, suggestions and contributions to carsten(at)strotmann.de

(1) ABBUC JHV = annual meeting and fair of the german Atari 8Bit club, called ABBUC; usually in autumn/fall (October); held in Herten (Western Germany);

(2) Schreiersgruen = another annual meeting of Atarians, usually in spring time (March); held in Schreiersgruen (eastern Germany);