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TOTAL BEGINNERS GUIDE ***********DEFINITIONS********* *********** If you're not familiar with the programming `lingo',then you'll find this list of definitions handy when reading other files on this disk. COMMAND-A command,or instruction,is a key word that has a special function when entered into AMOS's Editor-A command that you might use is "Print",or "Load",or "Return",the AMOS manuals are full of commands("AMOS" has 500,"Easy AMOS" has 350,and "AMOS Professional" has around 700).A command(When used `correctly')makes AMOS do something(This could ve displaying text,adding to a number,testing the joystick,saving a picture,and many more things). You must remember that each command has its own special set of rules-Its very rare if you can just enter a command on its own,you'll usually have to add various numbers,or combine it with other commands to make it work correctly.YOU CAN USE A COMMAND AS MANY TIMES AS YOU WANT TO. PROGRAM-A program is a `list' of commands that you(or someone else)type into a computer,this can be as long or as short as you want-Depending want you want it to do-and when it is `started'(Or "ran")the computer `reads' all the commands,and hopefully does what you want it to. LISTINGS-These are what some people call programs as they are seen in their text form(like they are in the AMOS Editor or example programs printed in magazines or books)-In other words,the programs are LISTS of commands,hence the word "Listings". CODE-In a similar way to listings,this is what you might hear programming commands reffered to as. RUN-When a list of commands have been typed into a computer(In other words,the program has been written),it can be "Run"-Which means that the computer reads each of the commands and performs the tasks that they have `set out'. If you had written: Print "HELLO EVERYONE" When run,AMOS would read the instruction-See what you wanted to display- and then put the following on screen: HELLO EVERYONE When the computer is reading through the commands and when the program is working,it is said to be "Running". LOOP-A loop is basically what the word suggests-Something that turns over and repeats itself.A loop in AMOS(Or any programming language)will contain several lines of commands which all serve a specific purpose.A loop is useful in a program which checks for a keypress,joystick movement or another precise action;Since you can't predict exactly when the player/user is going to do something,you have to keep checking-Which is where the loop comes in;You put all your `checking' commands within the loop and when a certain thing happens,you can react to it. There are many types of loops in AMOS-They are generally made up of two commands-One at the start of the loop,and one at the end-This is what you might call the structure of the loop. Here are a few of the loop commands in AMOS:"Do....Loop","Repeat...Until", "While....Wend". SUBROUTINE-Besides the `main' part of your programs,at some point you'll create a program too big to include everything in a single `loop',or you'll want to keep some commands seperate from the rest of the program,only using them at certain points-Which is where subroutines come in. They're like small programs that are typed in alongside the main one,with a special label to declare when they start(This can be almost anything you like-But you usually call a subroutine something to do with its actual contents),they all serve their own special purpose(Or purposes)-Such as detecting if the player has been hit or if the condition of something has changed-When its done what it has been `told' to,you can make AMOS return to the main part of the program or go onto another subroutine. GRAPHICS-For you TOTAL BEGINNERS,who have no knowledge of computers,graphics are the computer generated pictures which you can produce by drawing them in a computer `paint package' such as "Deluxe Paint",`digitizing'(transforming information to computer data),or actually allowing the computer to `draw' them via various maths routines(fractals and Ray-Traced pictures are a good example of this).You can now display these pictures in AMOS. Graphics are anything visual on computer,such as the icons you click on or the things that whizz around the screen in a game. SPRITES-If you've played(more or less)any type of computer game,you've undoubtedly seen a Sprite.It might have been a space ship in "Project X" or an Ogre in the "Ultima" series. Sprites are the graphic elements on a screen that you(via the computer) can manipulate-You can leave them in one place for as long as you like,or move it around screen with the joystick,mouse,keyboard,or even allow the computer to `look after them',by using simple maths commands or the revolutionary AMAL system. Sorry "Easy AMOS" users,due to the restrictions made for your version of AMOS,neither Sprites or AMAL are available to you. BOBS-Bobs are like the little brothers of Sprites-Whereas Sprites are `controlled' by the Amigas more powerful hardware,Bobs are controlled by the Blitter chip-Their name means Blitter Object. Unlike Sprites,Bobs are available to Easy AMOS users,can be larger,there can be more of them and they can be more colourful-One of their restrictions is that they are slower when moved around screen,but thankfully,Sprites and Bobs can be on screen at the same time,and can interact with each other to a certain point. (BOBS CAN ALSO BE MOVED WITH AMAL) AMAL-The AMOS Animation Language.This area of AMOS is a little complicated for beginners,but the basic ideas are covered here. If you want to move a Bob,Sprite or even an entire screen around,AMAL can help you.Instead of typing in a couple of commands,AMAL has its own little language,and to make sure AMOS knows you are using it,you have to put AMAL programs within inverted commas. AMAL programs can move objects,or produce animation effects(By `flipping' through several images-Just like `real life' animation). If you wanted to move a Bob from left to right and back again repeatedly,AMAL can do this-And because it works `seperately' from the rest of your program,it is much quicker and more effeciant than doing all the `leg work' yourself with simple maths formula(Like "X=X+1"). A simple AMAL program might look like this: Amal 1,"Move 200,0,50" Obviously,you need a few more commands to make this work,but it moves whtever object it has been written for 200 pixels (or computer screen dots) to the right,in 50 steps-So the object will move 4 pixels at a time until it has moved 200 pixels from its original starting place. COLLISION DETECTION-When you fire a laser bolt at an alien in "Space Invaders",you need someway of checking to see if it hit it-This is what collision detction does-It detects collisions(Or in plain english,it sees if one thing has bumped into something else).If the computer notices that one Bob or Sprite has touched another,it can be made to report this,allowing you to make something else happen(Eg.If a space ship gets hit by an asteroid,you might want an explosion sound to play,and a flash of fire to appear). Of course,you don't have to use space ships and aliens,just look at any action game available at the moment to see what they involve. SCROLL-This basically means movement.Typically the movement of our view point along screens(Horizontally or vertically). Various effects can be achieved with scrolling-Such as multi layering screens on top of one another to create the `parallax' effect(Several screens on top of one another-merged by the "Dual Playfield" command-And scrolled,sometimes in different directions,at different speeds. SOUND CHANNELS-(Or `Tracks')In order to replicate `stereo' sound effects on your Amiga,there are 4 channels of sound available for your use-Think of these as four speakers attached to a record player;You can turn these on and off at will,playing some sounds through certain speakers and other sounds throught the other `speakers'.Sound(Or music) can be played through as many of the sound channels as you wish. SCREEN-As you'd expect this is the thing you're looking at right now-A T.V. or Monitor screen-when we refer to them in AMOS,we're not actually talking about the box infront of you,but the viewing `window' which displays graphics etc..These can be set larger or smaller than the actual physical screen you can see now,so you might have to make the computer move(Or scroll) around them. In AMOS we can have upto 8 screens,and show any one of them we want-The advantage of this is that while you're loading a picture into the visible screen,you might be `writing' some text on another,ready to switch between the two when you like. A computer screen is `made' of many thousands of tiny dots(Called PIXELS), which can be coloured individually(Or in blocks,or all together)in upto 4096 (Or 16 million on the newer AGA machines)different colours. LOW RES(Or Lo Res)-This is a `screen mode'.It affects the visual aspect of the screen.It means low resolution -Which in itself means that the screen will be `made up' of slightly bigger pixels than other screen modes(Such as Hi Res and Med Res),which makes any graphics displayed on it look less smooth.A typical Low Res screen measures 320 pixels horizontally,by 256 pixels vertically;these sizes can be set higher or lower-This doesn't change the resolution,only the size of the screen. MED RES-(Meaning Medium Resolution)As above,this is a `screen mode'-Although it is not available to AMOS users. It has a `finer' look to it than Low Res-A typical screen in this mode measures 640 pixels horizontally,by 200 pixels vertically. HI RES-(Meaning High Resolution)This is another `screen mode'-And is available to AMOS users. This is the `finest' and smoothest mode,but a Hi Res screen can have a maximum of 16 colours only. Usually a Hi Res screen measures 640 pixels horizontally,by 400 pixels vertically. FILES-A file is an individual part(Or segment) of the disk,it may contain a program,graphics or sound-These various files can be accessed by the AMOS user in several easy ways. DISK DRIVE-A disk drive(As if you didn't know)is the thing on the side of the computer that you put disks in.With AMOS,you'll often have to state which disk drive you're accessing a file from-This might be "DF0"-Which is the internal drive,or "DF1" which is the first external drive.You'll often hear a disk drive reffered to as just a `drive'-It means the same thing,so don't worry. DIRECTORY(Or Drawer)-A disk doesn't always contain a list of files,sometimes you(Or whoever put the disk together)will have put several files of one type together,by putting them in a directory or drawer(Read your Workbench manual for more information about creating new drawers/directories),which is then given its own name(This is defined by the user and can be almost anything). When loading from,or saving to a certain directory,you must always the directory name,or AMOS will not be able to find your file. (THINK OF A DISK AS THE YELLOW PAGES,AND A DIRECTORY AS A SECTION-LIKE ALL THE PLUMBERS IN THE AREA-IF YOU DON'T SAY THAT YOU WANT THE PLUMBERS SECTION,SOMEBODY ELSE WOULDN'T BE ABLE TO FIND THE PLUMBERS YOU ARE TALKING ABOUT(OR THE FILE YOU WANT)). DF0-"DF0" refers to the Amigas internal disk drive. DF1-"DF1" refers to the first external disk drive connected to the Amiga. HARD DRIVE(Or Hard Disk)-Unlike a normal `floppy' disk(The 3.5 Inch plastic ones),a hard drive is a device which allows many more times the storage capacity-Allowing whole programs that take up many disks to be put on it-The access time(The time it takes for the computer to `read' information)is also much shorter,allowing for a much more efficient machine-A hard drive isn't essential,but it is certainly useful. SYNTAX-This refers to the way in which AMOS commands should be typed into the AMOS Editor.You may have experienced this problem when trying to run a program and AMOS tells you that there is a "Syntax Error"-This means that you have either forgotten to enter something,you've entered too much,or you've entered it in the wrong order.For example : "HELLO" Print Would make AMOS detect a syntax error-If you had wanted it to display the text within the inverted commas,you should have typed: Print "Hello" Or maybe you typed: Bob 1,20,20 This would generate a syntax error-If you had wanted to display Bob one in the top left hand corner of the screen,you have forgotten its image number (And assuming you would have used image 1),so you'd type: Bob 1,20,20,1 If you do get a syntax error,look in your AMOS manual to see how the command should be entered. (Syntax errors can also be caused by mis-spelling a command) MEMORY-When reffering to how much space a computer has within it to store pictures,sound Bobs/Sprites etc. we use the word memory. BANK-In a similar manner to a bank that contains money,a bank in AMOS is used to store various things-Such as Bobs,Sprites,music,sampled sound etc. These banks can be created in the special editors that AMOS provides for us(Like the "Sprite Bank Maker" or the "Sample Bank Maker" or from within AMOS itself. You can only store things in their specific banks(Although certain things can be put in any available bank)-"AMOS" and "Easy AMOS" have 16 banks available,whereas "AMOS Professional" has 65535!! But the more banks you fill up,the more memory you use. THE EDITOR-No,this isn't the person who runs "The Times",but the place where you type in your programs and edit them.