[comp.sys.atari.st] VT100 clear screen; Reading chars from ST screen

hase@netmbx.UUCP (Hartmut Semken) (06/28/88)

In article <8806212005.AA08722@ucbvax.Berkeley.EDU> F026@CPC865.UEA.AC.UK writes:
>>(Wil Groenen) writes:
>>> I have a problem [...] reading a character from screen at current
>>> cursor position.
>>I do not have detailed knowledge about this (my manuals aren't here
>>at the moment), but I would theorise that this is not possible.

Tja, what is the "current cursor position" on a bitmap screen using a
proportional spaced font? Whats a Cursor anyway? :-)
>
>Just to reduce the damper put on that idea, that's exactly what Acorn's
>BBC Micro did: there was a system call to read the bits under the current
>cursor position & compare them with the character bit-maps held in ROM,
>to allow screen editing in modes 0-6.

Puh!
The Acorn machines are very well thought about. Before sold (if sold 
at all :-)

>The BBC Micro was a 6502 8-bit machine running at standard speed (1MHz?):
>I'm sure a 68000 can do as well!
Remember: the 68000 is just twice to 3 times as fast as a 6502 (I still
love my Apple ][!)

Comp.sys.atari.st just gave me a little C program to do just that:
compare the bitmap on the screen with the ROM-Font (witch ist not
proportional :-).

hase

PS: my inews does not understand me.
-- 
Hartmut Semken, Lupsteiner Weg 67, 1000 Berlin 37 hase@netmbx.UUCP
High on a rocky promontory sat an Electric Monk on a bored horse. (D. Adams)