A83: Animation with _ILine

[Prev][Next][Index][Thread]

A83: Animation with _ILine


Hi!

I've been watching this mailing list for some time and therefore I'm sure
you will be able to help me. My problem is the following: I want to use the
built-in routine of the TI83 for drawing lines to make an animation of an
rotating hexagon. I tried to do it like this: (who reads all this
voluntarily??? skip the code and read on at the bottom of the mail)

.NOLIST
#define end .end
#define END .end
#define equ .equ
#define EQU .equ
#include "ti83asm.inc"
#include "tokens.inc"
.LIST

.org 9327h  ;*** Hauptprogramm ***/main program
MainLoop:
  ld   a,18  ;Zähler auf 18 setzen/set counter to 18
  ld   hl,Daten
GLoop:
  push af
  push hl
  ld   de,PLOTSSCREEN+1    ;clear display (OK, calling clrLCDFULL might do
it as well)
  ld   hl,PLOTSSCREEN
  ld   (hl),0
  ld   bc,768
  ldir
  call _GRBUFCPY_V ;buffer-->screen
  ld   a,0FFh  ;* Tastaturabfrage * (Tastaturreset)/keyboard reset and query
  out  (1),a
  ld   a,0FDh  ;Tastengruppe 2/key group 2
  out  (1),a
  in   a,(1)
  cp   191  ;=Clear gedrückt/"clear" pressed
  jr   z,Exit  ;-->Exit
  ;Animation
  pop  hl  ;Datenzeiger/data pointer
  ld   d,(hl)  ;Koord. 1. Endpunkt nach DE
  inc  hl
  ld   e,(hl)
  inc  hl
  push hl  ;Datenzeiger präservieren
  ld   bc,47*256+50 ;1. Startpunkt
  call Linie  ;1. Linie
  ld   d,b  ;2. Endpunkt: X bleibt gleich, Y=63-Ye1
  ld   a,63  ;63-->A = A=63
  sub  c  ;-C = A=63-Ye1
  ld   e,a  ;A-->E = Ye2=63-Ye1
  push de  ;Koordinaten brauchen wir nochmal
   call Linie  ;2. Linie
   ld   de,47*256+14 ;3. Endpunkt
   call Linie  ;3. Linie
  pop  de  ;4. Endpunkt: X=94-Xe1, Y bleibt gleich (d.h. Y=Ye2=63-Ye1)
  ld   a,94    ;94-->A
  sub  d  ;-D = A=94-Xe2
  ld   d,a  ;A-->D = Xe4=94-Xe2
  call Linie  ;4. Linie
  ld   d,b  ;5. Endpunkt: X bleibt gleich, Y=63-Ye4
  ld   a,63  ;63-->A = A=63
  sub  c  ;-C = A=63-Ye4
  ld   e,a  ;A-->E = Ye5=63-Ye4
  call Linie  ;5. Linie
  ld   de,47*256+50 ;1. Startpunkt = 6. Endpunkt
  call Linie
  pop  hl  ;fertig->Datenzeiger holen/get data pointer
  pop  af
  dec  a  ;A--
  jr   nz,GLoop
  xor  a
  jr   MainLoop
Exit:
  pop  hl
  pop  af
  ret

Linie:
  ld   h,1
  push de
  call _ILine  ;zeichnet Linie von B,C nach D,E/draws a line from B,C to D,E
  pop  bc  ;n. Endpunkt = (n+1). Startpunkt/second point of line n=first
point of line (n+1)
  ret

Daten:
  .db  77,39, 75,39, 73,40, 70,40, 66,40, 62,40, 57,40, 52,40, 47,40
  .db  42,40, 37,40, 37,40, 32,40, 28,40, 24,40, 21,40, 19,39, 17,39

.end
END

Now, what it does is: It clears the display, checks for the "clear"-key
being pressed and if not draws the next hexagon of the animation by calling
"Linie" six times (once for each line). The sub-routine "Linie" itself calls
"_ILine" to draw the line. The problem is that ILine not only draws the line
but also copies the graph buffer to the screen. On an emulator it may look
quite OK, but because of the slow LCD display it flickers terribly on the
TI.
What I suppose is that it would look much better if one could find a
possibility to make ILine not copying the buffer to the display after each
line (which wastes a lot of time), but to do this manually after all the six
lines have been drawn. Then you could even add a little pause without
slowing down the whole thing too much. I've tried this by setting the flags
"plotdisp,(iy+plotflags)" and "plotloc,(iy+plotflags)" but it didn't change
anything.

Perhaps someone finds a solution. I'd be very glad if so.

Alexander Mann
Follow-Ups: