clipper.txt

一个可以制作出和DELPHI很接近的IDE的好控健。只是稍微老了点。

// "Snake" - A screen Saver for Clipper V5.
//
//      Patrick Imbault
//      6 Rue de l'Ecluse
//      77000 MELUN
//      FRANCE
//      CIS:100012,1450
//
//  call SNAKE() to use it, it returns always .T.
//  compile CLIPPER snake /N /W

#Define SPEED      .1
#Define LMAX       15
#Define FRAC(x)    (x - INT(x))
#Define S_SNAKE(x) (SUBSTR(CHR(176) + CHR(177) + CHR(178) + CHR(219), x, 1))
#Define SIGN(x)    IIF(x > 0, 1, IIF(x < 0, -1, 0))

STATIC seed

FUNCTION SNAKE
  LOCAL i, nXd := 0, nYd := 0, nLon, nDiff, nAvis, nForm, nLon2, nP, nP2
  LOCAL cSc, nrow := row(), ncol := col(), anc_cu
  seed := FRAC(seconds() / 1000)
  nP := ARRAY(LMAX, 2)
  nP[1, 1] := 40
  nP[1, 2] := 12
  nAvis := MAX(5, alea(LMAX))
  nForm := MAX(5, alea(LMAX))
  cDir(@nXd, @nYd)
  nLon := MAX(4, alea(10))
  nLon2 := nLon
  FOR i := 2 TO nLon
    nP[i, 1] := nP[1, 1]
    nP[i, 2] := nP[1, 2] - (i - 1)
  NEXT i
  cSc := savescreen(0, 0, maxrow(), maxcol())
  CLEAR SCREEN
  anc_cu := setcursor(0)
  sdisp(nP, nLon)
  DO WHILE inkey(SPEED) == 0
    if nAvis-- < 0
      nAvis := MAX(5, alea(LMAX))
      cdir(@nXd, @nYd)
    endif
    if nForm-- < 0
      nForm := MAX(5, alea(LMAX))
      nLon2 := MAX(4, alea(10))
    ENDIF
    sundisp(nP, nLon)
    nDiff := nLon2 - nLon
    cPos(@nP, @nXd, @nYd, nLon, nDiff > 0)
    nLon += SIGN(nDiff)
    sdisp(nP, nLon)
  ENDDO
  restscreen(0, 0, maxrow(), maxcol(), cSc)
  setcursor(anc_cu)
  setpos(nrow, ncol)
RETURN .T.

FUNCTION sundisp(nP, nLon)
  LOCAL j
  FOR j := 1 TO nLon
    @ nP[j, 2], nP[j, 1] say "  "
  NEXT j
RETURN NIL

FUNCTION sdisp(nP, nLon)
  LOCAL i := 1, j
  FOR j := nLon TO 1 STEP -1
    @ nP[j, 2], nP[j, 1] say REPLICATE(S_SNAKE(INT(i)), 2)
    i += (4 / nLon)
  NEXT j
RETURN NIL

FUNCTION cpos(nPa, nXd, nYd, nLon, inc)
  LOCAL i, x, y
  x := nPa[1, 1] + nXd
  y := nPa[1, 2] + nYd
  DO WHILE x < 0 .OR. x > MAXCOL() .OR. y < 0 .OR. y > MAXROW()
    cdir(@nXd, @nYd)
    x := nPa[1, 1] + nXd
    y := nPa[1, 2] + nYd
  ENDDO
  FOR i := nLon + IIF(inc <> NIL .AND. inc, 1, 0) TO 2 STEP -1
    nPa[i, 1] := nPa[i - 1, 1]
    nPa[i, 2] := nPa[i - 1, 2]
  NEXT i
  nPa[1, 1] := x
  nPa[1, 2] := y
RETURN NIL

FUNCTION cdir(x, y)
  x := alea(3) - 1
  y := alea(3) - 1
  DO WHILE x = 0 .AND. y = 0
    x := alea(3) - 1
    y := alea(3) - 1
  ENDDO
RETURN NIL

FUNCTION alea(nX)
  seed := FRAC(seed * 9821 + .211327)
RETURN INT(seed * nX)