Home » Archimedes archive » Acorn User » Acorn User - Shareware Collection (1993).adf » Zap » !Zap/Docs/E-Cursors
!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 » Acorn User » Acorn User - Shareware Collection (1993).adf » Zap |
| Filename: | !Zap/Docs/E-Cursors |
| Read OK: | ✔ |
| File size: | 0A25 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 Window hasn't got the input. 1 car_cursor & car_selection Standard editing 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 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. 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 57 69 6e 64 6f 77 |lection...Window| 000002e0 20 68 61 73 6e 27 74 20 67 6f 74 20 74 68 65 20 | hasn't got the | 000002f0 69 6e 70 75 74 2e 0a 0a 31 09 63 61 72 5f 63 75 |input...1.car_cu| 00000300 72 73 6f 72 20 26 20 63 61 72 5f 73 65 6c 65 63 |rsor & car_selec| 00000310 74 69 6f 6e 09 53 74 61 6e 64 61 72 64 20 65 64 |tion.Standard ed| 00000320 69 74 69 6e 67 0a 0a 32 09 63 61 72 5f 63 75 72 |iting..2.car_cur| 00000330 73 6f 72 09 09 09 53 70 6c 69 74 20 63 75 72 73 |sor...Split curs| 00000340 6f 72 20 63 6f 70 79 69 6e 67 0a 09 63 61 72 5f |or copying..car_| 00000350 69 6e 70 75 74 09 09 09 63 61 72 5f 63 75 72 73 |input...car_curs| 00000360 6f 72 3d 6d 6f 76 69 6e 67 20 63 75 72 73 6f 72 |or=moving cursor| 00000370 0a 09 63 61 72 5f 73 65 6c 65 63 74 69 6f 6e 09 |..car_selection.| 00000380 09 09 63 61 72 5f 69 6e 70 75 74 3d 77 68 65 72 |..car_input=wher| 00000390 65 20 69 6e 70 75 74 20 67 6f 65 73 0a 0a 33 09 |e input goes..3.| 000003a0 63 61 72 5f 73 65 6c 65 63 74 69 6f 6e 09 09 09 |car_selection...| 000003b0 53 65 6c 65 63 74 20 61 72 65 61 20 76 69 61 20 |Select area via | 000003c0 6b 65 79 62 6f 61 72 64 0a 09 09 09 09 09 63 61 |keyboard......ca| 000003d0 72 5f 63 75 72 73 6f 72 3d 63 75 72 72 65 6e 74 |r_cursor=current| 000003e0 20 70 6f 73 6e 0a 09 09 09 09 09 0a 34 09 63 61 | posn.......4.ca| 000003f0 72 5f 73 65 6c 65 63 74 69 6f 6e 09 09 09 53 65 |r_selection...Se| 00000400 6c 65 63 74 20 61 72 65 61 20 76 69 61 20 6d 6f |lect area via mo| 00000410 75 73 65 0a 09 09 09 09 09 63 61 72 5f 63 75 72 |use......car_cur| 00000420 73 6f 72 3d 63 75 72 72 65 6e 74 20 70 6f 73 6e |sor=current posn| 00000430 0a 09 09 09 09 09 0a 35 09 63 61 72 5f 69 6e 70 |.......5.car_inp| 00000440 75 74 20 26 20 63 61 72 5f 73 65 6c 65 63 74 69 |ut & car_selecti| 00000450 6f 6e 09 53 65 6c 65 63 74 20 76 69 61 20 6d 6f |on.Select via mo| 00000460 75 73 65 20 77 69 74 68 20 43 54 52 4c 20 68 65 |use with CTRL he| 00000470 6c 64 0a 09 09 09 09 09 63 61 72 5f 63 75 72 73 |ld......car_curs| 00000480 6f 72 3d 63 75 72 72 65 6e 74 20 70 6f 73 6e 0a |or=current posn.| 00000490 09 09 09 09 09 63 61 72 5f 69 6e 70 75 74 3d 66 |.....car_input=f| 000004a0 69 78 65 64 20 63 75 72 73 6f 72 0a 0a 54 68 65 |ixed cursor..The| 000004b0 20 6f 66 66 73 65 74 73 20 6f 66 20 61 20 63 75 | offsets of a cu| 000004c0 72 73 6f 72 20 62 6c 6f 63 6b 20 68 61 76 65 20 |rsor block have | 000004d0 6e 61 6d 65 73 20 62 65 67 69 6e 6e 69 6e 67 20 |names beginning | 000004e0 27 63 5f 27 2e 20 41 73 20 75 73 75 61 6c 2c 20 |'c_'. As usual, | 000004f0 74 68 65 0a 45 2d 4c 69 62 72 61 72 79 20 66 69 |the.E-Library fi| 00000500 6c 65 20 64 65 66 69 6e 65 73 20 74 68 65 73 65 |le defines these| 00000510 20 6f 66 66 73 65 74 73 20 66 6f 72 20 79 6f 75 | offsets for you| 00000520 2e 20 54 68 65 79 20 61 72 65 20 64 65 73 63 72 |. They are descr| 00000530 69 62 65 64 20 62 65 6c 6f 77 2e 20 42 79 0a 63 |ibed below. By.c| 00000540 6f 6e 76 65 6e 74 69 6f 6e 2c 20 52 31 30 20 69 |onvention, R10 i| 00000550 73 20 75 73 65 64 20 74 6f 20 70 6f 69 6e 74 20 |s used to point | 00000560 74 6f 20 61 20 63 75 72 73 6f 72 20 62 6c 6f 63 |to a cursor bloc| 00000570 6b 2e 0a 0a 63 5f 77 69 6e 64 0a 57 69 6e 64 6f |k...c_wind.Windo| 00000580 77 20 6f 66 66 73 65 74 20 6f 66 20 61 73 73 6f |w offset of asso| 00000590 63 69 61 74 65 64 20 77 69 6e 64 6f 77 20 28 75 |ciated window (u| 000005a0 73 65 20 5a 61 70 5f 43 6f 6e 76 57 69 6e 64 4f |se Zap_ConvWindO| 000005b0 66 66 29 2e 20 54 68 69 73 20 6f 66 66 73 65 74 |ff). This offset| 000005c0 20 69 73 20 2d 31 0a 69 66 20 74 68 65 20 63 75 | is -1.if the cu| 000005d0 72 73 6f 72 20 69 73 20 6e 6f 74 20 62 65 69 6e |rsor is not bein| 000005e0 67 20 75 73 65 64 2e 0a 0a 63 5f 6c 69 6e 65 09 |g used...c_line.| 000005f0 09 43 75 72 72 65 6e 74 20 6c 69 6e 65 20 63 75 |.Current line cu| 00000600 72 73 6f 72 20 69 73 20 6f 6e 2e 0a 63 5f 63 6f |rsor is on..c_co| 00000610 6c 09 09 43 75 72 72 65 6e 74 20 63 6f 6c 75 6d |l..Current colum| 00000620 6e 20 63 75 72 73 6f 72 20 69 73 20 6f 6e 2e 0a |n cursor is on..| 00000630 63 5f 6f 66 66 09 09 43 75 72 72 65 6e 74 20 66 |c_off..Current f| 00000640 69 6c 65 20 6f 66 66 73 65 74 20 6f 66 20 63 75 |ile offset of cu| 00000650 72 73 6f 72 2e 0a 63 5f 6c 6f 66 66 09 09 43 75 |rsor..c_loff..Cu| 00000660 72 72 65 6e 74 20 66 69 6c 65 20 6f 66 66 73 65 |rrent file offse| 00000670 74 20 6f 66 20 73 74 61 72 74 20 6f 66 20 70 68 |t of start of ph| 00000680 79 73 69 63 61 6c 20 6c 69 6e 65 20 6f 66 20 63 |ysical line of c| 00000690 75 72 73 6f 72 2e 0a 63 5f 77 69 64 74 68 09 09 |ursor..c_width..| 000006a0 57 69 64 74 68 20 6f 66 20 63 75 72 73 6f 72 20 |Width of cursor | 000006b0 69 6e 20 63 68 61 72 61 63 74 65 72 73 2e 0a 0a |in characters...| 000006c0 63 5f 6f 77 69 6e 64 09 09 57 69 6e 64 6f 77 20 |c_owind..Window | 000006d0 6f 66 20 6f 6c 64 20 63 75 72 73 6f 72 20 70 6f |of old cursor po| 000006e0 73 69 74 69 6f 6e 2e 0a 63 5f 6f 6c 69 6e 65 09 |sition..c_oline.| 000006f0 09 4c 69 6e 65 20 6f 66 20 6f 6c 64 20 63 75 72 |.Line of old cur| 00000700 73 6f 72 20 70 6f 73 69 74 69 6f 6e 2e 0a 63 5f |sor position..c_| 00000710 6f 63 6f 6c 09 09 43 6f 6c 75 6d 6e 20 6f 66 20 |ocol..Column of | 00000720 6f 6c 64 20 63 75 72 73 6f 72 20 70 6f 73 69 74 |old cursor posit| 00000730 69 6f 6e 2e 0a 63 5f 6f 77 69 64 74 68 09 4f 6c |ion..c_owidth.Ol| 00000740 64 20 63 75 72 73 6f 72 20 77 69 64 74 68 2e 0a |d cursor width..| 00000750 0a 54 68 65 20 61 62 6f 76 65 20 6d 65 61 6e 69 |.The above meani| 00000760 6e 67 73 20 68 6f 6c 64 20 66 6f 72 20 63 61 72 |ngs hold for car| 00000770 5f 63 75 72 73 6f 72 20 61 6e 64 20 63 61 72 5f |_cursor and car_| 00000780 69 6e 70 75 74 2e 20 46 6f 72 20 63 61 72 5f 73 |input. For car_s| 00000790 65 6c 65 63 74 69 6f 6e 20 74 68 65 0a 63 75 72 |election the.cur| 000007a0 72 65 6e 74 20 63 75 72 73 6f 72 20 70 6f 73 69 |rent cursor posi| 000007b0 74 69 6f 6e 20 69 73 20 74 68 65 20 73 74 61 72 |tion is the star| 000007c0 74 20 6f 66 20 74 68 65 20 73 65 6c 65 63 74 69 |t of the selecti| 000007d0 6f 6e 20 61 6e 64 20 74 68 65 20 6f 6c 64 20 63 |on and the old c| 000007e0 75 72 73 6f 72 0a 70 6f 73 69 74 69 6f 6e 20 67 |ursor.position g| 000007f0 69 76 65 73 20 74 68 65 20 65 6e 64 20 6f 66 20 |ives the end of | 00000800 74 68 65 20 73 65 6c 65 63 74 69 6f 6e 2e 20 41 |the selection. A| 00000810 6c 73 6f 20 63 5f 6f 77 69 64 74 68 20 67 69 76 |lso c_owidth giv| 00000820 65 73 20 74 68 65 20 65 6e 64 20 6f 66 66 73 65 |es the end offse| 00000830 74 0a 6f 66 20 74 68 65 20 73 65 6c 65 63 74 69 |t.of the selecti| 00000840 6f 6e 2e 20 63 5f 77 69 64 74 68 20 69 73 20 75 |on. c_width is u| 00000850 6e 75 73 65 64 2e 20 42 79 20 73 74 61 72 74 20 |nused. By start | 00000860 61 6e 64 20 65 6e 64 20 49 20 6d 65 61 6e 20 6c |and end I mean l| 00000870 6f 67 69 63 61 6c 20 73 74 61 72 74 0a 61 6e 64 |ogical start.and| 00000880 20 65 6e 64 2e 20 54 68 75 73 2c 20 69 74 20 6d | end. Thus, it m| 00000890 61 79 20 6e 6f 74 20 68 6f 6c 64 20 74 68 61 74 |ay not hold that| 000008a0 20 74 68 65 20 73 74 61 72 74 20 63 6f 6d 65 73 | the start comes| 000008b0 20 62 65 66 6f 72 65 20 74 68 65 20 65 6e 64 20 | before the end | 000008c0 69 6e 20 74 68 65 0a 66 69 6c 65 2e 0a 0a 54 6f |in the.file...To| 000008d0 20 61 6c 74 65 72 20 61 20 63 75 72 73 6f 72 73 | alter a cursors| 000008e0 20 70 6f 73 69 74 69 6f 6e 20 79 6f 75 20 73 68 | position you sh| 000008f0 6f 75 6c 64 20 66 69 72 73 74 20 73 74 6f 72 65 |ould first store| 00000900 20 74 68 65 20 6e 65 77 20 70 6f 73 69 74 69 6f | the new positio| 00000910 6e 20 69 6e 20 74 68 65 0a 63 75 72 72 65 6e 74 |n in the.current| 00000920 20 70 6f 73 69 74 69 6f 6e 20 76 61 72 69 61 62 | position variab| 00000930 6c 65 73 2e 20 54 68 65 20 65 61 73 69 65 73 74 |les. The easiest| 00000940 20 77 61 79 20 74 6f 20 64 6f 20 74 68 69 73 20 | way to do this | 00000950 69 73 20 74 6f 20 73 74 6f 72 65 20 74 68 65 20 |is to store the | 00000960 6e 65 77 0a 6f 66 66 73 65 74 20 69 6e 20 63 5f |new.offset in c_| 00000970 6f 66 66 20 61 6e 64 20 74 68 65 6e 20 63 61 6c |off and then cal| 00000980 6c 20 5a 61 70 5f 55 70 64 61 74 65 43 61 72 65 |l Zap_UpdateCare| 00000990 74 2e 20 59 6f 75 20 73 68 6f 75 6c 64 20 74 68 |t. You should th| 000009a0 65 6e 20 63 61 6c 6c 20 5a 61 70 5f 50 6c 6f 74 |en call Zap_Plot| 000009b0 0a 63 61 72 65 74 20 74 6f 20 6d 6f 76 65 20 74 |.caret to move t| 000009c0 68 65 20 63 61 72 65 74 20 6f 6e 20 73 63 72 65 |he caret on scre| 000009d0 65 6e 20 61 6e 64 20 75 70 64 61 74 65 20 74 68 |en and update th| 000009e0 65 20 6f 6c 64 20 6f 66 66 73 65 74 20 74 6f 20 |e old offset to | 000009f0 74 68 65 20 63 75 72 72 65 6e 74 0a 6f 66 66 73 |the current.offs| 00000a00 65 74 2e 20 5a 61 70 5f 52 65 66 6c 65 63 74 43 |et. Zap_ReflectC| 00000a10 61 72 65 74 20 63 6f 6d 62 69 6e 65 73 20 74 68 |aret combines th| 00000a20 65 73 65 2e 0a |ese..| 00000a25
.