Preliminary experimental - plotting function graph in a picture window..

I know that much more efficient ways exist using some of the free-ware programs available. I just wanted to do it in mIRC. Call it an exercise in MSL. Call it a bad whim. Still I hope some may find interest in this.

TODO: More optimized looping. MSL is slow, but this can run a lot faster (I'm sure)

Some strangeness about seeing differences between the use of drawdot vs. drawline (off by a pixel)

NOTE: This has as yet no formula parser. The function must be passed as a valid mIRC expression using a pre-chosen variable named $x (a script actually)

(On the command-line the ! escapes in the examples are not needed.)
So just enter like /plot $sin($x)
calls to $calc() are needed inside functions parameters if it contains expresions.

; Plotter

; F(x) plot

alias plot_init {
  if (!$window(@plot)) window -pk0e @plot 50 50 450 450
  if (!$hget(plot)) hmake plot 10
  hadd plot scale 100 100
  hadd plot offset 210 210
  hadd plot size 180 180
  hadd plot axes $rgb(255,255,255) 2
  hadd plot curve $rgb(127,255,127) 1
}

alias plot {
  if ($0 == 0) {
    echo -ag usage: plot F($x)
  }
  else {
    if (!$hget(plot)) plot_init
    echo -sg plotting $1-
    drawsave -b32 @plot plotundo.bmp
    var %sinvs $calc($scale(1)*$sin($skew).deg)
    var %cosv $cos($skew).deg
    var %x = $calc($ofs(1) - $size(1))
    while (%x < $calc($ofs(1)+$size(1))) {
      hadd plot x $calc((%x -$ofs(1)) / $scale(1))
      var %y_ $calc( [ $1- ] )
      if (%y_ == $null) goto error
      var %xs $calc(%x - %sinvs * %y_ )
      var %ys $calc(%y_ * %cosv)
      var %y $calc($ofs(2) - %ys * $scale(2))
      if (%x < $calc($ofs(1)-$size(1)+4)) echo -sg skew $x %x %xs %y_ $calc( [ $1- ] ) %y %y_
      if ($hget(plot,y_1)) { 
        ;&& ($calc(($hget(plot,y_1) - %y)^2) > 4)) {
        drawline -nr @plot $curve $hget(plot,x_1) $hget(plot,y_1) %xs %y
      }
      ;else drawdot -r @plot $curve $calc(%x +1) $calc(%y +1)
      hadd plot y_1 %y
      hadd plot x_1 %xs
      if ($hget(plot,drop) && 10 // %x) {
        drawline -nr @plot $curve $calc(%x -0) 210 $round(%xs +.5) $round($calc(%y +.5))
      }
      goto done

      :error
      hdel plot y_1
      echo -sg Error: $error
      reseterror

      :done
      inc %x
    }
    drawline @plot
    ;    hfree plot
    hdel plot y_1
  }
}

on *:close:@Plot: hfree plot

alias plot_clear { clear @plot | hfree plot }
alias plot_undo drawpic @plot 0 0 plotundo.bmp

;fast configurations access
alias -l axes return $hget(plot,axes)
alias -l curve return $hget(plot,curve)

; ofs,scale,size $1: 1->x; 2->y
alias -l ofs {
  return $gettok($hget(plot,offset),$1,32)
}
alias -l scale {
  return $gettok($hget(plot,scale),$1,32)
}
alias -l size {
  return $gettok($hget(plot,size),$1,32)
}
alias -l skew return $iif($hget(plot,skew),$v1,0)
alias -l x return $hget(plot,x)

; Demos / utils 
;--------------

alias plot_axes {
  if (!$hget(plot)) plot_init
  drawline -nr @Plot $axes $calc($ofs(1) - $size(1)) $ofs(2) $calc($ofs(1) + $size(1)) $ofs(2)
  drawline -nr @Plot $axes $ofs(1) $calc($ofs(2) - $size(2)) $ofs(1) $calc($ofs(2) + $size(2)) 
  drawline @plot
}
alias plot_cross {
  if (!$hget(plot)) plot_init
  plot $!x
  plot 0- $!x
  plot_axes
}
alias plot_hyper {
  if (!$hget(plot)) plot_init
  var %r 0.2
  while (%r <= 1.6) {
    plot    $!sqrt( $!calc( $!x ^ 2 - [ %r ] ^2) ) 
    plot 0- $!sqrt( $!calc( $!x ^ 2 - [ %r ] ^2) ) 
    inc %r 0.2
  }
}
alias plot_hyper_ {
  if (!$hget(plot)) plot_init
  var %r 0.2
  while (%r <= 1.6) {
    plot    $!sqrt( $!calc( $!x ^ 2 + [ %r ] ^2) ) 
    plot 0- $!sqrt( $!calc( $!x ^ 2 + [ %r ] ^2) ) 
    inc %r 0.2
  }
}

alias plot_wave {
  if (!$hget(plot)) plot_init
  hadd plot scale 50 25

  hadd plot curve $rgb(255,127,127) 1
  hadd plot drop $true
  plot $!sin($calc($x *1.75))

  hadd plot skew 135
  hadd plot curve $rgb(127,255,127) 1
  plot $!sin($calc($x *1.75))

  plot_axes
  drawline -r @plot $rgb(255,255,255) 2 $calc($ofs(1) - $size(1)) $calc($ofs(2) + $size(2)) $calc($ofs(1) + $size(1)) $calc($ofs(2) - $size(2))
  hdel plot skew
  hdel plot drop
}