ART MASTER LOADING INSTRUCTIONS: Type LOAD”"" then press ENTER key. ART MASTER CONTENTS (1) INTRODUCTION (2) GETTING STARTED AND QUICK START REFERENCE (3) ACCESSING COMMANDS (4) TEXT EDITOR (5) COMPILE (6) DECOMPILE (7) RETURN (8) JUMP (9) TEST (10) MEMORY CHECK/CHANGE (11) INSERT (12) DELETE (13) AREA RELOCATE (14) DRAWING A PICTURE (15) THE DEMONSTRATION (16) SUMMARY OF COMMANDS (17) CUSTOMISING ART MASTER (18) SAVING THE RESIDENT CODE (19) WHAT IS G.CODE? (c) Alternative Software Limited 1989 PROGRAMMERS-If you have written a good programme for ANY home computer, send it to us now for evaluation. We pay EXCELLENT royalties!! Your programme could be in the shops within 3 weeks!! SEND TO: ALTERNATIVE SOFTWARE Units 3-6 Baileygate Industrial Estate, Pontefract, West Yorkshire. We will acknowledge receipt of your programme same day. 1. INTRODUCTION ART MASTER is an advanced, self-contained Graphics manipulator for the 48K Spectrum. The program itself occupies a little over 14K of your machine, though only a small part of this need remain in the computer at all times. The program sits at the top of the computer's memory, this means that the maximum number of add-ons and other programs can be used alongside ART MASTER without need for modification. ART MASTER's main function is to allow many screens to be stored in the computer at the same time, though unlike the average screen compressor its compression ratio is nearly 99%. This means that at any one time hundreds of screens can be loaded into the Spectrum instead of the tens of screens others will allow. This makes the provision for large scale animation by redrawing small parts of screens so that they appear to move. But it doesn't stop there... With ART MASTER you can draw circles 600% faster than a normal Spectrum, fill in shapes with 10 different patterns, draw boxes, triangles, flip areas of the screen, the list goes on! All these commands add up to one thing, a vastly superior graphics package, whose output can be used in adventure games, educational software, business software, and just about every other application you can think of where pictures or large scale animation is required. If you're still not convinced load up the Demonstration on side 2 of the cassette and prepare to be amazed. 2. GETTING STARTED By far the best way to learn to use ART MASTER is to load it up and experiment, using the manual as a guide To load up the program type LOAD "" (See the Spectrum user guide). Set the level on your cassette recorder to around 7 (thats 3/4) and press play. The program should then load and run automatically, this will take about 4 minutes and will follow this process: First border will flash cyan/red then flash blue/yellow, after this the screen will print Program: ART MASTER, then after a few seconds it will go black. If this does not happen try a different volume level, if the program refuses to load after several attempts then consult your dealer. When the program has loaded you will be faced with a blank blue screen all except for a white asterisk (star) in the bottom left hand corner. This white asterisk is called the command cursor. The Basic variable 'a' has also been changed, it now holds the start address of the program. If at any stage you wish to re-enter the program from Basic simply type RANDOMISE USR a or RANDOMISE USR 51490. GETTING STARTED QUICK REFERENCE If you want to start drawing pictures before you treat the manual as a bedtime story, then heres an A-Z of the manual. First read Sections 2-5 then read Section 14, next find a simple picture to start with. After this you'll get the feel of the program and will be able to tackle the more detailed pictures like the ones on side two of the cassette. 3. ACCESSING COMMANDS The program, when loaded (See 'Getting Started') displays the white cursor mentioned earlier this indicates you are in Command Mode. Once in Command Mode you can access all of ART MASTER's commands by simply pressing the key that corresponds to that command. When the key has been pressed, the program will prompt you for any information it requires. This other information will be in the form of addresses etc. Just like your home address, an address indicates where pieces of code 'live' in the computer The addresses take the form of 5 digit numbers and are entered in decimal format (ordinary numbers). Pressing SHIFT & ZERO will delete the last digit entered, repeatedly pressing SHIFT ZERO will cause the whole number to be erased. Upon receiving the fifth digit of an address the enter key will be pressed automatically for you, if your number is less than S digits then pressing enter will allow you to proceed to the next stage. If at any stage you wish to exit the command you have selected then press the 'X' key and you will be returned to the Command Mode, Upon completion of the command, providing no error has been processed and that you have not selected TEXT EDITOR or RETURN, the white cursor will appear once more indicating you at again in Command Mode, 4. TEXT EDITOR This will be one of the most used commands you will encounter. To access the TEXT EDITOR press the 'E' key, the message TEXT EDITOR will appear and you will seem to be in Basic. Press ENTER once, you now have three extra commands at your fingertips. These are AUTO LINE NUMBERING, LINE EDITING & RENUMBERING. To access these commands simply hold down the SYMBOL SHIFT key and then press the first letter of the command (A=Auto, E=Edit & R=Renumber). You will be asked for some extra information which is entered as a decimal number in the usual way (see Accessing Commands). Each of these commands will now be discussed in turn. AUTO (SYMBOL SHIFT A) This command requires you to enter the step between each successive line number and then the line number to start from. Just pressing enter gives the default value of 10 in each case. Once initialised AUTO will produce a new line number after each line is entered. A REM statement is also included after the line number, this is to tell the Spectrum that the information typed after the REM statement is of no concern to it. REM stands for REMark, for more information on REM see the Spectrum manual To stop the computer generating new line numbers delete the current line number & REM statement, then press ENTER. Pressing ENTER is essential to turn off the auto line number generator. LINE EDITOR (SYMBOL SHIFT E) When the cursor (a > sign) is pointing to a line number it may be edited using SHIFT ONE (as in the Spectrum manual). Normally if the cursor is not pointing to the line number you require, you have to use SHIFT 6 for up and SHIFT 7 for down until the cursor is on the correct line. ART MASTER has a much better solution! Push ENTER to clear any Spectrum intervention, then SYMBOL SHIFT E. You will now be asked to enter the line number you wish to edit, doing so will put you into the edit mode with the line you requested. Just pressing ENTER in reply to the line number question will cause you to exit the command. If you forget to press ENTER to clear the Spectrum intervention and the last thing you did caused an error E.g. 'Break Cont repeats' etc, then you will be greeted with another error when you enter the edited line. This will be a 'Nonsence in Basic' error, and the line will remain unedited, the cursor will however now point to the line requested so you can either push ENTER and try again or use SHIFT ONE in the normal way. RENUMBER (SYMBOL SHIFT R) This command requires three pieces of information, STEP, START & NEW START. STEP is the gap between successive line numbers & defaults to 10 if no number is entered. START is the line number you wish to renumber from, this defaults to the first line if no value is entered. NEW START is the line number you wish the new line numbers to start from, the default is 10 once more. 5. COMPILER Having prepared your text file, the next thing to do is to compile it. To do this you must re-enter ART MASTER by typing RANDOMISE USR a or RANDOMISE USR 51490. Now press 'W' for compile mode, you will then be asked for the start address, type in a number between 28000 & 50000, (40000 is a good starting place). You will then be asked 'Auto Leader (Y/N)?'’A leader is a four byte link that tells the computer to expect G-CODE. If you want to run the picture from Basic or Machine Code then you will need a leader. If on the other hand you wish to run the picture as part of another picture e.g. by a CALL or JUMP then you must not have a leader. In about 99% of cases you will need a leader. Upon answering the leader question there will be a short delay, the length of which depends on the length of the text file. After this delay you will be informed of the end address of the code, take note of this, it will be vital if you intend to put lots of pictures end on. You are now back in Command Mode and are able to draw your picture using any of the 3 ways available (See Later). ERRORS If you have made a mistake in the text file then one of four error reports will appear. Mistake in line a This occurs when a spelling mistake has been made, a number has too many digits or a comma has been put in the wrong place. No End Instruction This occurs if you have forgotten to put an END instruction on the end of the text file. You forgot to define NAME The label 'NAME' has been encountered and no pointer has been given in the text file. Too many labels. This, the last of the errors, is also the most rare, it only occurs in the event you defining more than 25 labels. This being the case the chances are you are well enough acquainted with G-CODE to use Addresses instead. In each of these cases you are returned to TEXT EDITOR mode and the offending line is pointed to ready to be edited. 6. DECOMPILE As the name implies DECOMPILE is the reverse of COMPILE. Simply type 'Q' and then the Start Address of the block of G-CODE you wish to decompile. There will be a delay, this could be as long as 10 seconds for a very long block of code, then the white asterisk will re-appear. Providing the Start Address was pointing to a block of G-CODE, the old text file will have been replaced by a new text file relating to the G-CODE block. If the block of code was not G-CODE the delay could be as long as 2 minutes and will probably end in the error 'Out of Memory'. All being well the text file will now be a little different to the one you typed it in the first place. Four main differences can be seen, the first three are unimportant. These are: the shortest abbreviations are used, capital letters are used and the line increments are always in steps of five. The last of the four differences is very important LABELS ARE NOT DECOMPILED ONLY THE ADDRESS THEY POINT TO!!! e.g. The example given in the TEXT EDITOR section: 10 REM jumphello 20 REM plot 100,100 30 REM lhello 40 REM end If Compiled at 40000 with no leader it would Decompile to. 5 REM J40006 10 REM P1OO,1OO 15 REM E The reason for the number 40006 is that a JUMP takes up 3 bytes, and so does a PLOT (if declared for the first time [see What is G-CODE ? at the end of the manual]). If a leader had been used then the whole block would have been shifted down four bytes meaning the address would now be 40010. HINT If you use the Basic command CLEAR (address-1) [see Spectrum manual] before you compile your text file at 'address' then not only will you protect your code you will also safeguard yourself against one of the possible types crash. This crash is the one that performs a NEW function erasing the Basic but not the Code. Decompile will then allow you to recreate your text file after it has been lost. The other handy thing about using CLEAR is that it protects your code against being overwritten by the text file should you make a mistake using Decompile. DON'T FORGET if you use CLEAR you must also type LET a=$1490 to setup the variables again. 7. RETURN Type 'Y' to enter this mode, you will be returned to the Normal Spectrum. You must use this mode whenever loading or saving, printing or running a picture using RANDOMISE USR address. If you do any of the above in TEXT EDITOR MODE YOU MAY CRASH THE SYSTEM. If you wish to test which mode you are in once in Basic then hold down the SYMBOL SHIFT key and press A. If the word STOP appears then you are in RETURN mode, if AUTO starts up then you are in TEXT EDITOR mode. If the latter is the case then press 'X' to quit the AUTO command then type RANDOMISE USR a or RANDOMISE USR 51490 to enter ART MASTER then press 'Y'’to enter RETURN mode. 8. JUMP This is the first of the two 'in program' drawing commands. Pressing 'J' will cause you to be asked for the Start Address of the code. Answer this question in the usual way (see getting started). The picture is then drawn without the need to return to Basic and RANDOMISE USR address. The major advantage of this command is that you can draw picture elements, e.g. pictures with no leader (see compile) as well as pictures with leaders. Once the picture has been drawn you will be returned to Command Mode ready to continue with the next command. 9. TEST Pressing 'T' gets you into TEST mode, this is essentially the same as JUMP only after each command has been processed the system displays the address of the current command in the top right hand corner of the screen and waits for a key to be pressed. 'X' will exit at any stage. If either JUMP or TEST come across an error e.g. PLOT 250,200 (the y coordinate is too big for the Spectrum screen), the RETURN mode is selected and the error 'Integer out of range' is printed at the bottom of the screen. 10. MEMORY CHECK/CHANGE This command serves two functions. Firstly it lets you view the contents of any memory location & secondly you are able to change the contents of that location if you wish. Press 'M' followed by the Address of the location you wish to view, then either type ENTER to view and proceed to the next location or type a number (0-255) to change the contents of that location. Pressing 'X' will let you exit at any stage. Upon the third digit of the number being typed ENTER will automatically be pressed, if your number has less than 3 digits then press ENTER to proceed. In the event of the number being greater than 255 you will be asked for the number once more. 11. INSERT This commend, and the two others that accompany it allow you to manipulate the G-CODE down at object level. Press the 'I' key then enter the start of the insertion, the end of the block of code and finally the number of spaces to make. The command will then move everything from the start of the insertion to the end of the block down the memory by the number of spaces required. The resulting gap will then be filled with zeros. 12. DELETE This is the opposite to INSERT and takes the same form. Press the 'D' key to remove the required number of bytes from the starting point and move the end of the block back up the memory. The space created at the end of the memory is then filled with zeros so that it is ready for use. 13. AREA RELOCATE This command moves a block of code from one position to another. Press the 'A' key followed by the START of the block, the END of the block and then the NEW START/ The block will then be moved, or rather copied as the old block is not erased. 14. DRAWING A PICTURE If you already have the picture you wish to draw to hand, e.g. from a magazine then it is advisable to plan it on graph paper first. If you are composing a picture then again doing the design on graph paper is going to make it much easier later. You can get special Spectrum Screen mapped paper, but this is often very expensive and graph paper will do just as well. Next translate the picture into lines, curves, plots etc. Load up ART MASTER and select the TEXT EDITOR mode, select AUTO line numbering. then enter the lines, curves etc into the text file. It is often advisable to COMPILE the text file at various stages throughout the picture to make sure you haven't made a mistake as it is much easier to alter in the early stages of its development, than trying to find it later. When you've finished your picture you can relocate it anywhere in the Spectrum memory, providing that you haven't used JUMPs or CALLs. If you have then these will need to be changed to their new values using the MEMORY CHECK/CHANGE function. Now you know what extra commands you have at your fingertips, its time to find out what the function of the TEXT EDITOR is. ART MASTER's drawing instructions are entered in Basic and then they are compiled down to an ultra fast & exceedingly small block of code called G- CODE. This G-CODE may then be incorporated into your own programs to give graphics without using up all the memory. The drawing instructions are typed in after a REM statement to indicate to the Spectrum that they are extra to its normal command set. This is why AUTO produces the REM statement. Below is a list of the drawing instructions used by ART MASTER, each is also accompanied by a brief description. $ PLOT x,y This in the same as the Spectrum's own PLOT command and puts a dot on the screen at location x,y $ DRAW x,y This is a new command, it links the last point to the new point location x,y $ FILL x,y,z Again a new command, this allows you to fill any shape with one of ten patterns. x,y is the point to start from and z is the pattern number (1 to 10) $ CIRCLE x,y,z This is like a normal circle only 600% faster. Its centre is given by x,y and radius is given by z. $ ARC x,y,z This command draws an arc from the last position to x,y with a curve factor z. —-128=