ZX Time #05 14 декабря 2001

Программирование

Coder - scroller on the curb.

Encoders


                         Nicholas Vitenko


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  Editor's note: this time under 'Coder' to our shame went a 
little short. I believe that it happened only because it curbs

theme is pretty good 'chewed' in previous releases. And the 
effects on the curb quite similar to each other and may be 
subject to a simple formula "to detain and sent !':)...



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          Scroller on the curb



  I remember back in the early 90's, caught once on the eye 
toy, called it Qarx (sorry if wrong in name). Already I can not 
say what is its meaning, but one can remember exactly

- On the curb, in the menu, was running running
line. Koryavenkaya such twitching. We
then very surprised - scrolling text!
On the curb! And could not understand
as possible. But as time passed, and it became clear that on 
the curb possible to do very much, and running line - it's 
flowers ... 


  Appeared Insult megademo, some time later came an even 
greater masterpiece Multicolor-curb Art -

Rage ... There's a line running more smoothly than
in an antediluvian Qarx'e, and she looked
better. That's just ... Run faster.


  It was then that I decided to repeat it, but with
smoother movement. And
came the subject of discussion today:).


  I think the experienced border-maker is not difficult to 
understand how it works ... 


  Formed a special buffer, where
bukovok drawn images that you intend to put to flight (knobs, 
handles all !:)), and from the buffer, in fact, everything is 
drawn. Also, pre-formed address buffer delay (from maximum to 
minimum and from minimum to maximum). By which, depending on 
the position of scrolling text at the moment determined by the 
length of delay 'On the clocks', but rather - offset relative 
to the current situation. 


  That is, to move the line segment 'smoothly', necessary to 
sustain a certain number of cycles, and then increase that 
time, then another and another ... This is achieved by 'smooth' 
motion. 


  Sources - as always in the appendix.
There are no comments and the 'counting' cycles.


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