Home » Archimedes archive » Archimedes World » AW-1994-06-Disc2.adf » Disk2Jun94 » !AWJune94/Goodies/Zap/!Zap/Docs/E-Cursors
!AWJune94/Goodies/Zap/!Zap/Docs/E-Cursors
This website contains an archive of files for the Acorn Electron, BBC Micro, Acorn Archimedes, Commodore 16 and Commodore 64 computers, which Dominic Ford has rescued from his private collection of floppy disks and cassettes.
Some of these files were originally commercial releases in the 1980s and 1990s, but they are now widely available online. I assume that copyright over them is no longer being asserted. If you own the copyright and would like files to be removed, please contact me.
| Tape/disk: | Home » Archimedes archive » Archimedes World » AW-1994-06-Disc2.adf » Disk2Jun94 |
| Filename: | !AWJune94/Goodies/Zap/!Zap/Docs/E-Cursors |
| Read OK: | ✔ |
| File size: | 0B65 bytes |
| Load address: | 0000 |
| Exec address: | 0000 |
File contents
************************************************************************* * >E-Cursors Documents a cursor block format. * ************************************************************************* Zap currently supports 3 cursors. Each has a cursor block. The addresses of the blocks can be read via Zap_ReadVar (See E-Vars). I will call them after the names of their pointers, ie, car_cursor, car_input, car_selection. The second is not usually used. It is used in cursor mode 2, when the cursors are split for keyboard copying. The current cursor mode is stored in a variable called car_mode. Use Zap_ReadVar to get at this. Currently modes 0-5 are defined as below: Mode: Cursors updated on screen: Use: 0 car_selection Zap hasn't got the input. square where input should be 1 car_cursor & car_selection Standard editing cursor and input carets combined. 2 car_cursor Split cursor copying car_input car_cursor=moving cursor car_selection car_input=where input goes 3 car_selection Select area via keyboard car_cursor=current posn 4 car_selection Select area via mouse car_cursor=current posn 5 car_input & car_selection Select via mouse with CTRL held car_cursor=current posn car_input=fixed cursor Internally, Zap also uses the modes: -1 square where input should be Caret 'temporarily' lost by Zap. car_selection (Eg it is in a menu item) -2 car_selection only Used as a temporary value to scrub carets from the screen. The offsets of a cursor block have names beginning 'c_'. As usual, the E-Library file defines these offsets for you. They are described below. By convention, R10 is used to point to a cursor block. c_wind Window offset of associated window (use Zap_ConvWindOff). This offset is -1 if the cursor is not being used. c_line Current line cursor is on. c_col Current column cursor is on (including margin). c_off Current file offset of cursor. c_loff Current file offset of start of physical line of cursor. c_width Width of cursor in characters. c_owind Window of old cursor position. c_oline Line of old cursor position. c_ocol Column of old cursor position. c_owidth Old cursor width. The above meanings hold for car_cursor and car_input. For car_selection the current cursor position is the start of the selection and the old cursor position gives the end of the selection. Also c_owidth gives the end offset of the selection. c_width is unused. By start and end I mean logical start and end. Thus, it may not hold that the start comes before the end in the file. To alter a cursors position you should first store the new position in the current position variables. The easiest way to do this is to store the new offset in c_off and then call Zap_UpdateCaret. You should then call Zap_Plot caret to move the caret on screen and update the old offset to the current offset. Zap_ReflectCaret combines these.
00000000 2a 2a 2a 2a 2a 2a 2a 2a 2a 2a 2a 2a 2a 2a 2a 2a |****************| * 00000040 2a 2a 2a 2a 2a 2a 2a 2a 2a 0a 2a 20 3e 45 2d 43 |*********.* >E-C| 00000050 75 72 73 6f 72 73 09 44 6f 63 75 6d 65 6e 74 73 |ursors.Documents| 00000060 20 61 20 63 75 72 73 6f 72 20 62 6c 6f 63 6b 20 | a cursor block | 00000070 66 6f 72 6d 61 74 2e 09 09 09 2a 0a 2a 2a 2a 2a |format....*.****| 00000080 2a 2a 2a 2a 2a 2a 2a 2a 2a 2a 2a 2a 2a 2a 2a 2a |****************| * 000000c0 2a 2a 2a 2a 2a 0a 0a 5a 61 70 20 63 75 72 72 65 |*****..Zap curre| 000000d0 6e 74 6c 79 20 73 75 70 70 6f 72 74 73 20 33 20 |ntly supports 3 | 000000e0 63 75 72 73 6f 72 73 2e 20 45 61 63 68 20 68 61 |cursors. Each ha| 000000f0 73 20 61 20 63 75 72 73 6f 72 20 62 6c 6f 63 6b |s a cursor block| 00000100 2e 20 54 68 65 20 61 64 64 72 65 73 73 65 73 20 |. The addresses | 00000110 6f 66 0a 74 68 65 20 62 6c 6f 63 6b 73 20 63 61 |of.the blocks ca| 00000120 6e 20 62 65 20 72 65 61 64 20 76 69 61 20 5a 61 |n be read via Za| 00000130 70 5f 52 65 61 64 56 61 72 20 28 53 65 65 20 45 |p_ReadVar (See E| 00000140 2d 56 61 72 73 29 2e 20 49 20 77 69 6c 6c 20 63 |-Vars). I will c| 00000150 61 6c 6c 20 74 68 65 6d 20 61 66 74 65 72 0a 74 |all them after.t| 00000160 68 65 20 6e 61 6d 65 73 20 6f 66 20 74 68 65 69 |he names of thei| 00000170 72 20 70 6f 69 6e 74 65 72 73 2c 20 69 65 2c 20 |r pointers, ie, | 00000180 63 61 72 5f 63 75 72 73 6f 72 2c 20 63 61 72 5f |car_cursor, car_| 00000190 69 6e 70 75 74 2c 20 63 61 72 5f 73 65 6c 65 63 |input, car_selec| 000001a0 74 69 6f 6e 2e 20 54 68 65 0a 73 65 63 6f 6e 64 |tion. The.second| 000001b0 20 69 73 20 6e 6f 74 20 75 73 75 61 6c 6c 79 20 | is not usually | 000001c0 75 73 65 64 2e 20 49 74 20 69 73 20 75 73 65 64 |used. It is used| 000001d0 20 69 6e 20 63 75 72 73 6f 72 20 6d 6f 64 65 20 | in cursor mode | 000001e0 32 2c 20 77 68 65 6e 20 74 68 65 20 63 75 72 73 |2, when the curs| 000001f0 6f 72 73 20 61 72 65 0a 73 70 6c 69 74 20 66 6f |ors are.split fo| 00000200 72 20 6b 65 79 62 6f 61 72 64 20 63 6f 70 79 69 |r keyboard copyi| 00000210 6e 67 2e 0a 0a 54 68 65 20 63 75 72 72 65 6e 74 |ng...The current| 00000220 20 63 75 72 73 6f 72 20 6d 6f 64 65 20 69 73 20 | cursor mode is | 00000230 73 74 6f 72 65 64 20 69 6e 20 61 20 76 61 72 69 |stored in a vari| 00000240 61 62 6c 65 20 63 61 6c 6c 65 64 20 63 61 72 5f |able called car_| 00000250 6d 6f 64 65 2e 20 55 73 65 0a 5a 61 70 5f 52 65 |mode. Use.Zap_Re| 00000260 61 64 56 61 72 20 74 6f 20 67 65 74 20 61 74 20 |adVar to get at | 00000270 74 68 69 73 2e 20 43 75 72 72 65 6e 74 6c 79 20 |this. Currently | 00000280 6d 6f 64 65 73 20 30 2d 35 20 61 72 65 20 64 65 |modes 0-5 are de| 00000290 66 69 6e 65 64 20 61 73 20 62 65 6c 6f 77 3a 0a |fined as below:.| 000002a0 0a 4d 6f 64 65 3a 09 43 75 72 73 6f 72 73 20 75 |.Mode:.Cursors u| 000002b0 70 64 61 74 65 64 20 6f 6e 20 73 63 72 65 65 6e |pdated on screen| 000002c0 3a 09 55 73 65 3a 0a 0a 30 09 63 61 72 5f 73 65 |:.Use:..0.car_se| 000002d0 6c 65 63 74 69 6f 6e 09 09 09 5a 61 70 20 68 61 |lection...Zap ha| 000002e0 73 6e 27 74 20 67 6f 74 20 74 68 65 20 69 6e 70 |sn't got the inp| 000002f0 75 74 2e 0a 09 73 71 75 61 72 65 20 77 68 65 72 |ut...square wher| 00000300 65 20 69 6e 70 75 74 20 73 68 6f 75 6c 64 20 62 |e input should b| 00000310 65 0a 0a 31 09 63 61 72 5f 63 75 72 73 6f 72 20 |e..1.car_cursor | 00000320 26 20 63 61 72 5f 73 65 6c 65 63 74 69 6f 6e 09 |& car_selection.| 00000330 53 74 61 6e 64 61 72 64 20 65 64 69 74 69 6e 67 |Standard editing| 00000340 0a 09 09 09 09 09 63 75 72 73 6f 72 20 61 6e 64 |......cursor and| 00000350 20 69 6e 70 75 74 20 63 61 72 65 74 73 20 63 6f | input carets co| 00000360 6d 62 69 6e 65 64 2e 0a 0a 32 09 63 61 72 5f 63 |mbined...2.car_c| 00000370 75 72 73 6f 72 09 09 09 53 70 6c 69 74 20 63 75 |ursor...Split cu| 00000380 72 73 6f 72 20 63 6f 70 79 69 6e 67 0a 09 63 61 |rsor copying..ca| 00000390 72 5f 69 6e 70 75 74 09 09 09 63 61 72 5f 63 75 |r_input...car_cu| 000003a0 72 73 6f 72 3d 6d 6f 76 69 6e 67 20 63 75 72 73 |rsor=moving curs| 000003b0 6f 72 0a 09 63 61 72 5f 73 65 6c 65 63 74 69 6f |or..car_selectio| 000003c0 6e 09 09 09 63 61 72 5f 69 6e 70 75 74 3d 77 68 |n...car_input=wh| 000003d0 65 72 65 20 69 6e 70 75 74 20 67 6f 65 73 0a 0a |ere input goes..| 000003e0 33 09 63 61 72 5f 73 65 6c 65 63 74 69 6f 6e 09 |3.car_selection.| 000003f0 09 09 53 65 6c 65 63 74 20 61 72 65 61 20 76 69 |..Select area vi| 00000400 61 20 6b 65 79 62 6f 61 72 64 0a 09 09 09 09 09 |a keyboard......| 00000410 63 61 72 5f 63 75 72 73 6f 72 3d 63 75 72 72 65 |car_cursor=curre| 00000420 6e 74 20 70 6f 73 6e 0a 09 09 09 09 09 0a 34 09 |nt posn.......4.| 00000430 63 61 72 5f 73 65 6c 65 63 74 69 6f 6e 09 09 09 |car_selection...| 00000440 53 65 6c 65 63 74 20 61 72 65 61 20 76 69 61 20 |Select area via | 00000450 6d 6f 75 73 65 0a 09 09 09 09 09 63 61 72 5f 63 |mouse......car_c| 00000460 75 72 73 6f 72 3d 63 75 72 72 65 6e 74 20 70 6f |ursor=current po| 00000470 73 6e 0a 09 09 09 09 09 0a 35 09 63 61 72 5f 69 |sn.......5.car_i| 00000480 6e 70 75 74 20 26 20 63 61 72 5f 73 65 6c 65 63 |nput & car_selec| 00000490 74 69 6f 6e 09 53 65 6c 65 63 74 20 76 69 61 20 |tion.Select via | 000004a0 6d 6f 75 73 65 20 77 69 74 68 20 43 54 52 4c 20 |mouse with CTRL | 000004b0 68 65 6c 64 0a 09 09 09 09 09 63 61 72 5f 63 75 |held......car_cu| 000004c0 72 73 6f 72 3d 63 75 72 72 65 6e 74 20 70 6f 73 |rsor=current pos| 000004d0 6e 0a 09 09 09 09 09 63 61 72 5f 69 6e 70 75 74 |n......car_input| 000004e0 3d 66 69 78 65 64 20 63 75 72 73 6f 72 0a 0a 49 |=fixed cursor..I| 000004f0 6e 74 65 72 6e 61 6c 6c 79 2c 20 5a 61 70 20 61 |nternally, Zap a| 00000500 6c 73 6f 20 75 73 65 73 20 74 68 65 20 6d 6f 64 |lso uses the mod| 00000510 65 73 3a 0a 0a 2d 31 09 73 71 75 61 72 65 20 77 |es:..-1.square w| 00000520 68 65 72 65 20 69 6e 70 75 74 20 73 68 6f 75 6c |here input shoul| 00000530 64 20 62 65 09 43 61 72 65 74 20 27 74 65 6d 70 |d be.Caret 'temp| 00000540 6f 72 61 72 69 6c 79 27 20 6c 6f 73 74 20 62 79 |orarily' lost by| 00000550 20 5a 61 70 2e 0a 09 63 61 72 5f 73 65 6c 65 63 | Zap...car_selec| 00000560 74 69 6f 6e 09 09 09 28 45 67 20 69 74 20 69 73 |tion...(Eg it is| 00000570 20 69 6e 20 61 20 6d 65 6e 75 20 69 74 65 6d 29 | in a menu item)| 00000580 0a 0a 2d 32 09 63 61 72 5f 73 65 6c 65 63 74 69 |..-2.car_selecti| 00000590 6f 6e 20 6f 6e 6c 79 09 09 55 73 65 64 20 61 73 |on only..Used as| 000005a0 20 61 20 74 65 6d 70 6f 72 61 72 79 20 76 61 6c | a temporary val| 000005b0 75 65 20 74 6f 20 73 63 72 75 62 0a 09 09 09 09 |ue to scrub.....| 000005c0 09 63 61 72 65 74 73 20 66 72 6f 6d 20 74 68 65 |.carets from the| 000005d0 20 73 63 72 65 65 6e 2e 0a 0a 54 68 65 20 6f 66 | screen...The of| 000005e0 66 73 65 74 73 20 6f 66 20 61 20 63 75 72 73 6f |fsets of a curso| 000005f0 72 20 62 6c 6f 63 6b 20 68 61 76 65 20 6e 61 6d |r block have nam| 00000600 65 73 20 62 65 67 69 6e 6e 69 6e 67 20 27 63 5f |es beginning 'c_| 00000610 27 2e 20 41 73 20 75 73 75 61 6c 2c 20 74 68 65 |'. As usual, the| 00000620 0a 45 2d 4c 69 62 72 61 72 79 20 66 69 6c 65 20 |.E-Library file | 00000630 64 65 66 69 6e 65 73 20 74 68 65 73 65 20 6f 66 |defines these of| 00000640 66 73 65 74 73 20 66 6f 72 20 79 6f 75 2e 20 54 |fsets for you. T| 00000650 68 65 79 20 61 72 65 20 64 65 73 63 72 69 62 65 |hey are describe| 00000660 64 20 62 65 6c 6f 77 2e 20 42 79 0a 63 6f 6e 76 |d below. By.conv| 00000670 65 6e 74 69 6f 6e 2c 20 52 31 30 20 69 73 20 75 |ention, R10 is u| 00000680 73 65 64 20 74 6f 20 70 6f 69 6e 74 20 74 6f 20 |sed to point to | 00000690 61 20 63 75 72 73 6f 72 20 62 6c 6f 63 6b 2e 0a |a cursor block..| 000006a0 0a 63 5f 77 69 6e 64 0a 57 69 6e 64 6f 77 20 6f |.c_wind.Window o| 000006b0 66 66 73 65 74 20 6f 66 20 61 73 73 6f 63 69 61 |ffset of associa| 000006c0 74 65 64 20 77 69 6e 64 6f 77 20 28 75 73 65 20 |ted window (use | 000006d0 5a 61 70 5f 43 6f 6e 76 57 69 6e 64 4f 66 66 29 |Zap_ConvWindOff)| 000006e0 2e 20 54 68 69 73 20 6f 66 66 73 65 74 20 69 73 |. This offset is| 000006f0 20 2d 31 0a 69 66 20 74 68 65 20 63 75 72 73 6f | -1.if the curso| 00000700 72 20 69 73 20 6e 6f 74 20 62 65 69 6e 67 20 75 |r is not being u| 00000710 73 65 64 2e 0a 0a 63 5f 6c 69 6e 65 09 09 43 75 |sed...c_line..Cu| 00000720 72 72 65 6e 74 20 6c 69 6e 65 20 63 75 72 73 6f |rrent line curso| 00000730 72 20 69 73 20 6f 6e 2e 0a 63 5f 63 6f 6c 09 09 |r is on..c_col..| 00000740 43 75 72 72 65 6e 74 20 63 6f 6c 75 6d 6e 20 63 |Current column c| 00000750 75 72 73 6f 72 20 69 73 20 6f 6e 20 28 69 6e 63 |ursor is on (inc| 00000760 6c 75 64 69 6e 67 20 6d 61 72 67 69 6e 29 2e 0a |luding margin)..| 00000770 63 5f 6f 66 66 09 09 43 75 72 72 65 6e 74 20 66 |c_off..Current f| 00000780 69 6c 65 20 6f 66 66 73 65 74 20 6f 66 20 63 75 |ile offset of cu| 00000790 72 73 6f 72 2e 0a 63 5f 6c 6f 66 66 09 09 43 75 |rsor..c_loff..Cu| 000007a0 72 72 65 6e 74 20 66 69 6c 65 20 6f 66 66 73 65 |rrent file offse| 000007b0 74 20 6f 66 20 73 74 61 72 74 20 6f 66 20 70 68 |t of start of ph| 000007c0 79 73 69 63 61 6c 20 6c 69 6e 65 20 6f 66 20 63 |ysical line of c| 000007d0 75 72 73 6f 72 2e 0a 63 5f 77 69 64 74 68 09 09 |ursor..c_width..| 000007e0 57 69 64 74 68 20 6f 66 20 63 75 72 73 6f 72 20 |Width of cursor | 000007f0 69 6e 20 63 68 61 72 61 63 74 65 72 73 2e 0a 0a |in characters...| 00000800 63 5f 6f 77 69 6e 64 09 09 57 69 6e 64 6f 77 20 |c_owind..Window | 00000810 6f 66 20 6f 6c 64 20 63 75 72 73 6f 72 20 70 6f |of old cursor po| 00000820 73 69 74 69 6f 6e 2e 0a 63 5f 6f 6c 69 6e 65 09 |sition..c_oline.| 00000830 09 4c 69 6e 65 20 6f 66 20 6f 6c 64 20 63 75 72 |.Line of old cur| 00000840 73 6f 72 20 70 6f 73 69 74 69 6f 6e 2e 0a 63 5f |sor position..c_| 00000850 6f 63 6f 6c 09 09 43 6f 6c 75 6d 6e 20 6f 66 20 |ocol..Column of | 00000860 6f 6c 64 20 63 75 72 73 6f 72 20 70 6f 73 69 74 |old cursor posit| 00000870 69 6f 6e 2e 0a 63 5f 6f 77 69 64 74 68 09 4f 6c |ion..c_owidth.Ol| 00000880 64 20 63 75 72 73 6f 72 20 77 69 64 74 68 2e 0a |d cursor width..| 00000890 0a 54 68 65 20 61 62 6f 76 65 20 6d 65 61 6e 69 |.The above meani| 000008a0 6e 67 73 20 68 6f 6c 64 20 66 6f 72 20 63 61 72 |ngs hold for car| 000008b0 5f 63 75 72 73 6f 72 20 61 6e 64 20 63 61 72 5f |_cursor and car_| 000008c0 69 6e 70 75 74 2e 20 46 6f 72 20 63 61 72 5f 73 |input. For car_s| 000008d0 65 6c 65 63 74 69 6f 6e 20 74 68 65 0a 63 75 72 |election the.cur| 000008e0 72 65 6e 74 20 63 75 72 73 6f 72 20 70 6f 73 69 |rent cursor posi| 000008f0 74 69 6f 6e 20 69 73 20 74 68 65 20 73 74 61 72 |tion is the star| 00000900 74 20 6f 66 20 74 68 65 20 73 65 6c 65 63 74 69 |t of the selecti| 00000910 6f 6e 20 61 6e 64 20 74 68 65 20 6f 6c 64 20 63 |on and the old c| 00000920 75 72 73 6f 72 0a 70 6f 73 69 74 69 6f 6e 20 67 |ursor.position g| 00000930 69 76 65 73 20 74 68 65 20 65 6e 64 20 6f 66 20 |ives the end of | 00000940 74 68 65 20 73 65 6c 65 63 74 69 6f 6e 2e 20 41 |the selection. A| 00000950 6c 73 6f 20 63 5f 6f 77 69 64 74 68 20 67 69 76 |lso c_owidth giv| 00000960 65 73 20 74 68 65 20 65 6e 64 20 6f 66 66 73 65 |es the end offse| 00000970 74 0a 6f 66 20 74 68 65 20 73 65 6c 65 63 74 69 |t.of the selecti| 00000980 6f 6e 2e 20 63 5f 77 69 64 74 68 20 69 73 20 75 |on. c_width is u| 00000990 6e 75 73 65 64 2e 20 42 79 20 73 74 61 72 74 20 |nused. By start | 000009a0 61 6e 64 20 65 6e 64 20 49 20 6d 65 61 6e 20 6c |and end I mean l| 000009b0 6f 67 69 63 61 6c 20 73 74 61 72 74 0a 61 6e 64 |ogical start.and| 000009c0 20 65 6e 64 2e 20 54 68 75 73 2c 20 69 74 20 6d | end. Thus, it m| 000009d0 61 79 20 6e 6f 74 20 68 6f 6c 64 20 74 68 61 74 |ay not hold that| 000009e0 20 74 68 65 20 73 74 61 72 74 20 63 6f 6d 65 73 | the start comes| 000009f0 20 62 65 66 6f 72 65 20 74 68 65 20 65 6e 64 20 | before the end | 00000a00 69 6e 20 74 68 65 0a 66 69 6c 65 2e 0a 0a 54 6f |in the.file...To| 00000a10 20 61 6c 74 65 72 20 61 20 63 75 72 73 6f 72 73 | alter a cursors| 00000a20 20 70 6f 73 69 74 69 6f 6e 20 79 6f 75 20 73 68 | position you sh| 00000a30 6f 75 6c 64 20 66 69 72 73 74 20 73 74 6f 72 65 |ould first store| 00000a40 20 74 68 65 20 6e 65 77 20 70 6f 73 69 74 69 6f | the new positio| 00000a50 6e 20 69 6e 20 74 68 65 0a 63 75 72 72 65 6e 74 |n in the.current| 00000a60 20 70 6f 73 69 74 69 6f 6e 20 76 61 72 69 61 62 | position variab| 00000a70 6c 65 73 2e 20 54 68 65 20 65 61 73 69 65 73 74 |les. The easiest| 00000a80 20 77 61 79 20 74 6f 20 64 6f 20 74 68 69 73 20 | way to do this | 00000a90 69 73 20 74 6f 20 73 74 6f 72 65 20 74 68 65 20 |is to store the | 00000aa0 6e 65 77 0a 6f 66 66 73 65 74 20 69 6e 20 63 5f |new.offset in c_| 00000ab0 6f 66 66 20 61 6e 64 20 74 68 65 6e 20 63 61 6c |off and then cal| 00000ac0 6c 20 5a 61 70 5f 55 70 64 61 74 65 43 61 72 65 |l Zap_UpdateCare| 00000ad0 74 2e 20 59 6f 75 20 73 68 6f 75 6c 64 20 74 68 |t. You should th| 00000ae0 65 6e 20 63 61 6c 6c 20 5a 61 70 5f 50 6c 6f 74 |en call Zap_Plot| 00000af0 0a 63 61 72 65 74 20 74 6f 20 6d 6f 76 65 20 74 |.caret to move t| 00000b00 68 65 20 63 61 72 65 74 20 6f 6e 20 73 63 72 65 |he caret on scre| 00000b10 65 6e 20 61 6e 64 20 75 70 64 61 74 65 20 74 68 |en and update th| 00000b20 65 20 6f 6c 64 20 6f 66 66 73 65 74 20 74 6f 20 |e old offset to | 00000b30 74 68 65 20 63 75 72 72 65 6e 74 0a 6f 66 66 73 |the current.offs| 00000b40 65 74 2e 20 5a 61 70 5f 52 65 66 6c 65 63 74 43 |et. Zap_ReflectC| 00000b50 61 72 65 74 20 63 6f 6d 62 69 6e 65 73 20 74 68 |aret combines th| 00000b60 65 73 65 2e 0a |ese..| 00000b65
.