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Text File | 2004-01-01 | 11.2 KB | 432 lines

u DOTBASIC DOCUMENTATION Part 3 Welcome back! Let's get on with screen manipulation: CUT: .TC,x1,x2,y1,y2,loc PASTE: .TP,x1,x2,y1,y2,loc -------------------------- CUT and PASTE are able to stash and restore any size portion of the screen to or from any location, even under I/O. The data is stored sequentially in memory with each cell's screen code and color code stored one after another. This formula reveals how much memory is consumed by CUT: bytes = (x2-x1+1)*(y2-y1+1)*2 PASTE requires that you specify the area to be filled. As long as you use the same SIZE area as the cut data, you can PASTE it wherever you want, oodles of times. NOTE: DotBASIC has a better way! PASTE requires that the dimensions of the PASTEd "object" are the same as the CUT. This can be a hassle! So we have added OBJECT commands. First off, you must assign a location in memory for your objects. As with CUT and PASTE, the location can be anywhere, even under I/O. OBJECT SET: .OS,location ------------------------ This sets a place for NEW ojects and zeros the number of objects present. OBJECT LINK: .OL,location ------------------------- This links the Object commands to a location in memory without zeroing the number of objects present -- perfect when you BLOAD an Object File. OBJECT CUT: .OC,x1,x2,y1,y2 --------------------------- The cut object is placed in the next slot in the object area. The end+1 of the object area is returned in FP (for checking memory and BSAVEing). OBJECT PASTE: .OP,index,x,y --------------------------- This puts the indexed object on the screen, with x/y being the position of the upper left corner. OBJECT DELETE: .OD ------------------ This removes the last object. OBJECT NUMBER: O# ----------------- Returns the number of objects in the collection in I%. CHECK KEYPRESS: .KP,string -------------------------- This routine quickly scans your string and checks if any of those keys are being pressed at the moment. If one is, that key's position within the string will be returned in I%. Example: SYS ML+60,"dragon" If an "a" was being pressed, I% would return a value of 3. If no keys were being pressed, I% returns zero. Although the CRSR/RETURN keys already offer a means of "keyboard support", do not forget to add the convenience of hotkeys to your program! BIG NOTE: Some mouse buttons are mistaken for keyboard presses! Mouse Usually Can also be Button Seen as Mistaken for ------ ------- ------------ Left SPACE <RShift> .MBCZ <F1> Right nothing \+97531 <Delete> Middle b.arrow *PIYRW <Return> LET GO: .KR ----------- This command will wait until the user is not holding either of the mouse buttons (or their equivalents) down, even if it takes all day. COPYMEM:(,start,end+1,destination) ---------------------------------- COPY MEM: .CP,params SWAP MEM: .SW,params COPY I/O INTACT: .CI,params COPY CHR EXPOSED: .CC,params COPY MEM is the classic command. All ROMS are lifted and a raw memory transfer is performed. The speed: approximately 28 cycles per byte. SWAP MEM will swap the area of memory with that at the destination, at a rate of 41 cycles per byte. COPY I/O INTACT will lift the ROMS, but leave the $d000 area alone. This would be useful in copying the color RAM or the VIC-chip's settings. COPY CHAR EXPOSED will lift the ROMS, but expose the Character-ROM in the $d000 area so you can copy it. These routines all work under the protection of a SEI. When done, all ROMS are switched back in regardless of what location 1 held when called. In fact, this goes for all routines that switch out the ROMS. [Note:] Routines that operate under an SEI and may take over 1/60 of a second to complete, like STASH and COPYMEM, take a short break every so often to let the interrupt "pass by". While this isn't really important, it does keep the mouse moving fluidly even during large memory transfers. REGULAR MENU: .MU,x1,x2,y1,y2,u,h,"hotkeys" ----------------------------- This command creates a highlight bar that moves in sync with the mouse pointer, until a selection is made. When an item is clicked on, SL% will return that "selection" number, which will be anywhere from 1 to 25. U is the color of unhighlighted items in the menu. The highlight bar is colored H. If you do not want the text to reverse or un-reverse as the bar moves, add 128 to H. You can also use the CRSR/RETURN keys instead of a mouse or joystick. In order to provide a more natural menu interface, the "Keyboard Enable" variable at MV+20 is temporarily zeroed during menus. The CRSR keys are then read manually to move the highlight bar, one move per press, like we're all used to. The HOTKEY string allows direct selection of menu items. For example, if you have hotkeys of "loadst*r", and the user presses "d", the fourth item is selected and the highlight bar is moved there. If there was no such item, SL% still returns a 4 but the highlight bar would not change. MENUS can have "regions active" without the need to POKE to MV+10 or MV+11. Clicking on an active region from a menu will return the region number (plus 128) in SL%. The HOTKEYS would return "region-like" values. The H+64 feature of menus will only work if "honor hotkey colors" is enabled. A HOTKEY COLOR is just ANY color within the text of a menu which is neither the highlight nor un-highlight color. That leaves you with 14 colors to make your menu's hotkeys stand out, and stay that way. Related Variables: (& defaults) MV+10 Menu Type (192) MV+12 Global Escape (0) MV+12 holds the ASCII code for what you'd like to designate as the escape key for ALL your menus. SL% returns a zero when the escape key is pressed, except in one instance... MV+10 dictates how your regular menus will behave. Each bit stands for a specific menu feature. Just add up the values for the features you want and POKE that number to MV+10. +128 Automatic Caging of Mouse + 64 Automatic Point-to-First + 32 Must Select + 16 Escape Equal-to-Last + 8 Honor Hotkey Colors + 4 Dual Response + 2 Un-highlight after Select + 1 Stray-to-Exit +128 causes the mouse to be confined within the menu's borders. After a selection is made, the previous cage is restored. If auto-caging is not enabled, the user may be able to click on the area outside of the menu, which would return zero in SL% (unless it is an active region). +64 causes the mouse to be put at the rightmost cell of the first item the instant a regular menu is called. +32 causes nothing to happen if the user clicks on the area outside of the menu. The menu remains active as it waits for a real selection. +16 causes the escape key, when pressed, to automatically select the last item in your menu - just as if you pressed its hotkey. This saves some code if "Close this Menu" is the last item in your menus - especially when using the ON GOTO command. +8 causes the highlight bar to not change the colors of characters that have neither the Highlight nor Un-highlight color applied to them. This is an interesting way to inform users of your menu's hotkeys. To use this feature properly, you must make sure the entire menu area is colored in the Un-hilight color, except for the hotkey-characters. Merely PRINTing your menu items and calling the menu won't work right on older versions of the KERNAL. The areas on the right sides of your items might be colored white, or have the cursor color or background color applied to them. It's best to use BOX to draw a rectangle of spaces, THEN print your menu items. +2 causes the highlight bar to be removed after a selection is made. +1 causes the menu to be aborted if the mouse strays from the menu area. SL% is returned as zero if this happens. TEXT INPUT: .IN,x,y,t,c,length,default$ --------------------------- When called, the default string is printed at X,Y followed by a blinking cursor. The user can CRSR through the text, INSERT, DELETE, HOME, or CLR at will. Most normal characters are allowed, except for those fearsome quotation marks. The string is returned in W$. T is the text color and C is the cursor color. LENGTH is the maximum number of characters allowed, which cannot and will not exceed 80. The default string will be cut short if it exceeds the allowed LENGTH. A nice thing about this INPUT is that it automatically clears out the space it needs, which is handy for inputting over fields that might contain old data. If you want to input in REVERSE, add 128 to X. If you want to allow only numbers to be entered, add 128 to Y. If you want to allow numbers AND the decimal and minus symbols, add 192 to Y. The Keyboard Enable variable at MV+20 is temporarily zeroed during the INPUT routine. It looks silly if the arrow pointer moves back and forth as you are CRSRing through the text. The Enhanced version (below) now also returns the cursor position (upon exit) in C%. ENHANCED INPUT: .IE,x,y,t,c,len,s,out$,def$ --------------------------- Just like REGULAR INPUT, the default string is printed at X,Y. T is the text color and C is the cursor color. L is the maximum length allowed, which can not and will not exceed 80. The user can CRSR through the text, HOME, CLR, INSERT, and DELETE at will. If you want to input in REVERSE, add 128 to X. If you want to allow only numbers to be entered, add 128 to Y. If you want to allow numbers AND the decimal and minus symbols, add 192 to Y. S is the STARTing location of the blinking cursor. For example, if S was 7, then the cursor would pop up over the 8th character of the default string. Why not the 7th? Well, zero is used to represent the leftmost (1st) character. If you positioned your INPUT against the left border, you'd see that S corresponds to the usual 0-39 Cell-X values. If S exceeds the length of the default string, the cursor would pop up right after the end of the default string. Since this string can never exceed 80 characters, any S value above 80 ensures the cursor will start off at its "normal" position at the end of the default string. OUT$ allows you to specify extra keys you want to act like RETURN. For example, you might have a list of figures and would like to be able to use CRSR UP/DOWN to move through each one, and then press F1 to signify when you're done altering the lot. The string is returned in W$. I% tells you WHICH exit-key was pressed. It is zero when RETURN is used, and any other value means that specific key from OUT$ was pressed to exit. Since the incoming keypresses are checked against OUT$ first, you could use CRSR LEFT, RIGHT, HOME, or ANY key to act as a special RETURN key. Of course, using LEFT and RIGHT as exit keys means they couldn't be used to move the blinking cursor within the current line of input. However, if you had a bunch of values in rows and columns, using all 4 CRSR keys to move through items would be handy! Don't touch that dial! Part 3 is chock full of good stuff!