X-Git-Url: http://git.shiar.nl/descalc.git/blobdiff_plain/375edfcd40c9aae752068931a7831a1dae3d0d7e..cbe6b523381a22a69f29a0e0865a83e7bb171838:/sdc.pl

diff --git a/sdc.pl b/sdc.pl
old mode 100644
new mode 100755
index 09541a0..b91c209
--- a/sdc.pl
+++ b/sdc.pl
@@ -1,42 +1,356 @@
 #!/usr/bin/perl
 
+### curses rpn desktop calculator ###
+
+# by Shiar <shiar.org>
+
+# 06-18       - start
+# 06-25       -
+# 08-04 14:45 - error dialog (don't mess up screen)
+
 use strict;
 use warnings;
+use utf8;
 
 use Term::ReadKey;
 use Curses;
 
 initscr;
-ReadMode 3;
+ReadMode 3;  # cbreak mode
+END {
+	ReadMode 0;
+	endwin;
+} # restore terminal on quit
 
-my $height = $LINES-3;
-my $width = 42; #COLS
+my $height = $LINES<3 ? 4 : $LINES-3;  # stack depth (lines of stack plus one)
+my $width = $COLS || 42;  # limit value precision, stetch menu
 
+my %val = qw(i 0  frac 0);  # i, frac
 my @stack;
-my @val;
-my $nopush; # 0=push and reset next; 1=reset next; 2=do nothing
-my $base = 10;
+my %var;
 my @menu;
+my $menumin;
+my %set = (
+	base     => 10,
+	numb     =>  0,  # fixed scientific engineering
+	card     =>  1,  # degrees radians grades
+	coord    =>  0,  # cartesian polar spherical
+	complex  =>  0,  # real complex
+	menushow =>  6,
+); # %set
+
+my @menus = (
+	[qw(refresh math>8 prog> mode>7 unit>11)],
+	[qw(main>0 log alog ln exp sin cos tan 0 asin acos atan)], #1 math
+	[qw(main>0 dec bin oct hex logic>3 bit>4)], #2 base
+	[qw(base>2 and or xor not)], #3 base logic
+	[qw(base>2 rl sl asr sr rr)], #4 base bit
+	[qw(base>2 rlb slb srb rrb)], #5 base byte
+	[qw(main>0 sq sqrt ^ xroot)], #6
+	[qw(main>0 number_format angle_measure coord_system)], #7 mode
+	[qw(main>0
+		vector> matrix> list> hyperbolic>9 real>10 base>2
+		probability> fft> complex> constants>
+	)], #8 math
+	[qw(math>8
+		sinh cosh tanh asinh acosh atanh
+		expm lnp1
+	)], #9 math hyperbolic
+	[qw(math>8
+		% %ch %t min max mod
+		abs sign mant xpon ip fp
+		rnd trnc floor ceil r>d d>r
+	)], #10 math real
+	[qw(main>0
+		tools> length>12 area>13 volume>14 time>15 speed>16
+		mass>17 force>18 energy>19 power>20 pressure>21 temperature>22
+		electric_current>23 angle>24 light>25 radiation>26 viscosity>27
+	)], #11 units
+#		mm cm m in ft yd km mile mmile lt-yr mil Ang fermi rod fath)],
+	[qw(unit>11
+		_m _cm _mm _yd _ft _in _Mpc _pc _lyr _au _km _mi
+		_nmi _miUS _chain _rd _fath _ftUS _Mil _μ _Å _fermi
+	)], #12 length
+	[qw(unit>11
+		_m^2 _cm^2 _b _yd^2 _ft^2 _in^2
+		_km^2 _ha _a _mi^2 _miUS^2 _acre
+	)], #13 area
+	[qw(unit>11
+		_m^3 _st _cm^3 _yd^3 _ft^3 _in^3
+		_l _galUK _galC _gal _qt _pt
+		_ml _cu _ozfl _ozUK _tbsp _tsp
+		_bbl _bu _pk _fbm
+	)], #14 volume
+	[qw(unit>11
+		_yr _d _h _min _s _Hz
+	)], #15 time
+	[qw(unit>11
+		_m/s _cm/s _ft/s _kph _mph _knot
+		_c _ga
+	)], #16 speed
+	[qw(unit>11
+		_kg _g _Lb _oz _slug _lbt
+		_ton _tonUS _t _ozt _ct _grain
+		_u _mol
+	)], #17 mass
+	[qw(unit>11
+		_N _dyn _gf _kip _lbf _pdl
+	)], #18 force
+	[qw(unit>11
+		_J _erg _Kcal _Cal _Btu _ftxlbf
+		_therm _MeV _eV
+	)], #19 energy
+	[qw(unit>11
+		_W _hp
+	)], #20 power
+	[qw(unit>11
+		_Pa _atm _bar _psi _torr _mmHg
+		_inHg _inH2O
+	)], #21 pressure
+	[qw(unit>11
+	)], #22 temperature
+	[qw(unit>11
+	)], #23 electric_current
+	[qw(unit>11
+	)], #24 angle
+	[qw(unit>11
+	)], #25 light
+	[qw(unit>11
+	)], #26 radiation
+	[qw(unit>11
+	)], #27 viscosity
+
+
+
+); # @menus
+@menu = @{$menus[0]};
+$menumin = 0;
+
+my %falias = (
+	"\033"                         =>  0, # esc
+	"\033\117\120"                 =>  1, # f1
+	"\033\133\061\061\176"         =>  1, # f1
+	"\033\133\061\062\176"         =>  2, # f2
+	"\033\133\061\063\176"         =>  3, # f3
+	"\033\133\061\064\176"         =>  4, # f4
+	"\033\117\121"                 =>  2, # f2
+	"\033\117\122"                 =>  3, # f3
+	"\033\117\123"                 =>  4, # f4
+	"\033\133\061\065\176"         =>  5, # f5
+	"\033\133\061\067\176"         =>  6, # f6
+	"\033\133\061\070\176"         =>  7, # f7
+	"\033\133\061\071\176"         =>  8, # f8
+	"\033\133\062\060\176"         =>  9, # f9
+	"\033\133\062\061\176"         => 10, # f10
+	"\033\133\062\063\176"         => 11, # f11/F1
+	"\033\133\062\064\176"         => 12, # f12/F2
+	"\033\133\062\065\176"         => 13, # F3
+	"\033\133\062\066\176"         => 14, # F4
+	"\033\133\062\070\176"         => 15, # F5
+	"\033\133\062\071\176"         => 16, # F6
+	"\033\133\063\061\176"         => 17, # F7
+	"\033\133\063\062\176"         => 18, # F8
+	"\033\133\063\063\176"         => 19, # F9
+	"\033\133\063\064\176"         => 20, # F10
+	"\033\133\062\063\073\062\176" => 21, # F11
+	"\033\133\062\064\073\062\176" => 22, # F12
+); # %falias
 
-INIT: {
+my %alias = (
+	chr 4 => 'quit', # ^D
+	chr 9 => 'more', # tab
+	'_' => 'chs', # change sign; 48: y
+	'e' => 'eex', # exponent; 48: z
+#	"\033\133\062\176" => 'swap', # ins
+	chr(27).chr(91).chr(51).chr(126) => 'clear', # del
+	chr 127 => 'drop', # backspace
+	chr 8 => 'drop', # backspace
+	chr 13 => ' ', # enter
+	"\014" => 'refresh', # ^L
+#	"\033\133\110" => 'refresh', # home
+
+#	"\033\133\101" => '', # up; 48: k (stack)
+#	"\033\133\104" => '', # left; 48: p (picture)
+#	"\033\133\102" => '', # down; 48: q (view)
+	"\033\133\103" => 'swap', # right; 48: r (swap)
+
+	'&' => 'and',
+	'|' => 'or',
+	'#' => 'xor',
+	'~' => 'not',
+
+	        's' => 'sin',
+	chr(27).'s' => 'asin',
+	        'c' => 'cos',
+	chr(27).'c' => 'acos',
+	        't' => 'tan',
+	chr(27).'t' => 'atan',
+	        'l' => 'log',
+	chr(27).'l' => 'alog',
+	        'n' => 'ln',
+	chr(27).'n' => 'exp',
+	        'q' => 'sq',
+	chr(27).'q' => 'sqrt',
+	chr(27).'^' => 'xroot',
+); # %alias
 
-@stack = ();
-@val = (0, 0); # val, frac
-$nopush = 1;
+=cut
+HP48 keys:
+    S     T     U      V     W     X
+ -  sin   cos   tan    sqrt  ^     1/x
+ <  asin  acos  atan   sq    alog  exp
+ >  [a]   ∫     ∑      xroot log   ln
+=cut
 
+my %action = (
+	'more' => [0, sub {
+		$menumin += $set{menushow};
+		$menumin = 0 if $menumin>=$#menu;
+		showmenu();
+	}], # tab
+	'digit'=> [-2, sub { $val{i} = ($val{frac} *= 10) ? $val{i}+$_/$val{frac} : $val{i}*10+$_ }],
+	'.'    => [-2, sub { $val{frac} = 1 }], # decimal point
+	'eex'  => [-2, sub {}], # exponent
+	'chs'  => [0, sub {
+		if (defined $val{i}) {
+			$val{i} = -$val{i};
+		} else {
+			$stack[0] = -$stack[0];
+		}
+	}], # negative
+
+	'drop' => [0, sub {
+		if (defined $val{i}) {
+			$val{i} = ($val{frac} = int $val{frac}/10)
+				? int($val{i}*$val{frac})/$val{frac} : int $val{i}/10
+		} else {
+			shift @stack;
+		}
+	}], # backspace
+	'clear'  => [0, sub {
+		#todo: if (val{i}) delete char after cursor
+		@stack = (); %val = (i=>undef, frac=>0)
+	}], # clear all
+
+	' '    => [0, sub {
+		unshift @stack, $val{i};
+		%val = (i=>undef, frac=>0);
+	}], # duplication
+
+	'swap' => [1, sub {@stack[0, 1] = @stack[1, 0]}], # swap x<->y
+
+	'='    => [1, sub {$var{a} = $stack[0]}], # copy
+	'>'    => [1, sub {$var{a} = shift @stack}], # assign
+
+	'+'    => [2, sub {$stack[1] += shift @stack}], # addition
+	'-'    => [2, sub {$stack[1] -= shift @stack}], # substraction
+	'*'    => [2, sub {$stack[1] *= shift @stack}], # multiplication
+	'/'    => [2, sub {$stack[1] /= shift @stack}], # division
+	'mod'  => [2, sub {$stack[1] %= shift @stack}], # modulo
+
+	'sqrt' => [1, sub {$stack[0] = sqrt $stack[0]}], # square root
+	'sq'   => [1, sub {$stack[0] *= $stack[0]}], # squared
+	'^'    => [2, sub {$stack[1] **= shift @stack}], # exponentiation
+	'xroot'=> [2, sub {$stack[1] **= 1 / shift @stack}], # x-root of y
+
+	'log'  => [1, sub {$stack[0] = log($stack[0]) / log(10)}], # logarithm
+	'alog' => [1, sub {$stack[0] = 10 ** $stack[0]}], # 10^x
+	'ln'   => [1, sub {$stack[0] = log $stack[0]}], # natural logaritm
+	'lnp1' => [1, sub {$stack[0] = log($stack[0]+1)}], # ln(x+1)
+	'exp'  => [1, sub {$stack[0] = exp($stack[0])}], # e^x
+	'expm' => [1, sub {$stack[0] = exp($stack[0])-1}], # exp(x)-1
+
+	'sin'  => [1, sub {$stack[0] = sin $stack[0]}], # sine
+	'asin' => [1, sub {$stack[0] = atan2($stack[0], sqrt(1 - $stack[0]*$stack[0]))}], # inverse sine
+	'cos'  => [1, sub {$stack[0] = cos $stack[0]}], # cosine
+	'acos' => [1, sub {$stack[0] = atan2(sqrt(1 - $stack[0]*$stack[0]), $stack[0])}], # inverse cosine
+	'tan'  => [1, sub {$stack[0] = sin($stack[0]) / cos($stack[0])}], # tangent
+#	'atan' => [1, sub {}], # arctangent
+
+	'%'    => [2, sub {$stack[0] /= shift @stack}], # percentage
+	'%ch'  => [2, sub {$val{i} = 100*(shift(@stack)-$val{i})/$val{i}}], # percentage change
+	'%t'   => [2, sub {$val{i} = 100*$val{i}/shift(@stack)}], # percentage total
+
+	'and'  => [2, sub {$stack[1] &= shift @stack}], # bitwise and
+	'or'   => [2, sub {$stack[1] |= shift @stack}], # bitwise or
+	'xor'  => [2, sub {$stack[1] ^= shift @stack}], # bitwise xor
+	'not'  => [2, sub {$stack[0] = ~$stack[0]}], # bitwise not
+
+	'abs'  => [1, sub {$stack[0] = abs $stack[0]}], # absolute #todo
+	'sign' => [1, sub {$stack[0] = $stack[0] <=> 0}], # sign
+	'ip'   => [1, sub {$stack[0] = int $stack[0]}], # integer part
+	'fp'   => [1, sub {$stack[0] -= int $stack[0]}], # fractional part
+
+	'rnd'  => [1, sub {local $_ = 10**shift @stack; $val{i} = int(($val{i}+.5)*$_)/$_}], # round
+	'trnc' => [1, sub {local $_ = 10**shift @stack; $val{i} = int($val{i}*$_)/$_}], # truncate
+	'floor'=> [1, sub {$stack[0] = int $stack[0]}], # floor
+	'ceil' => [1, sub {$stack[0] = int $stack[0]+.9999}], # ceil
+
+	'min'  => [2, sub {
+		local $_ = shift @stack;
+		$stack[0] = $_ if $_<$stack[0];
+	}], # minimum
+	'max'  => [2, sub {
+		local $_ = shift @stack;
+		$stack[0] = $_ if $_>$stack[0];
+	}], # maximum
+
+	'dec'  => [0, sub {$set{base} = 10}], # decimal
+	'bin'  => [0, sub {$set{base} = 2}], # binary
+	'oct'  => [0, sub {$set{base} = 8}], # octal
+	'hex'  => [0, sub {$set{base} = 16}], # hexadecimal
+	'base36' => [0, sub {$set{base} = 36}], # alphanumerical
+); # %action
+
+my %unit;
+{
+my $i = 0;
+$unit{$_->[0]} = { name=>$_->[0], type=>$i, val=>$_->[1] } for map {$i++; @$_} (
+	[
+		['m', 1],
+		['cm', .01],
+		['mm', .001],
+		['km', 1000],
+		['ft', .3048],
+		['in', .0254],
+		['yd', .9144],
+		['mile', 1609.344],
+		['nmile', 1852],
+		['lyr', 9.46052840488e+15],
+		['mil', 2.54e-5],
+	#		_m _cm _mm _yd _ft _in _Mpc _pc _lyr _au _km _mi
+	#		_nmi _miUS _chain _rd _fath _ftUS _Mil _μ _Å _fermi
+	], # lengths
+	[
+		['m^3', 1],
+		['cm^3', 1e-6],
+		['ft^3', .028316846592],
+		['in^3', 1.6387064e-5],
+	], # volume
+);
+} # create unit table
+
+
+sub showval($$);
 sub showval($$) {
 	my ($val, $base) = @_;
+	return '' unless defined $val;
 	return $val if $base==10;
 
 	my $int = int $val;
 	my $frac = $val-$int;
+	my $exp = 0;
 
 	my $txt = '';
+	while ($int>$base**10) {
+		$int /= $base;
+		$exp++;
+	} # exponent part
 	while ($int>=1) {
 		my $char = $int%$base;
 		$txt = ($char<10 ? $char : chr($char+55)).$txt;
 		$int /= $base;
-	}
+	} # integer part
 
 	$txt .= '.' if $frac>0;
 	for (my $i = 0; length $txt<$width-2 && $frac>0; $i++) {
@@ -44,148 +358,45 @@ sub showval($$) {
 		my $char = int $frac;
 		$frac -= $char;
 		$txt .= $char<10 ? $char : chr($char+55);
-	}
+	} # fraction part
+
+	$txt .= 'e'.showval($exp, $base) if $exp;
 
 	return $txt;
 } # showval
 
 sub showstack() {
 	for (0..@stack-1) {
-		addstr($height-$_, 1, "$_: ".showval($stack[$_], $base));
+		addstr($height-$_, 1, "$_: ".showval($stack[$_], $set{base}));
 		clrtoeol;
 	} # show stack
 	clrtoeol($height-$#stack-1, 1);
 } # showstack
 
-sub showmenu($) {
-	my @menus = ([qw(xroot log alog)], [qw(dec bin oct hex)]);
-	@menu = @{$menus[shift]};
-	attron(A_REVERSE);
-	addstr($height+2, $width/6*$_+1, join " ", $menu[$_]) for grep exists $menu[$_], 0..5;
-	attroff(A_REVERSE);
-	clrtoeol;
-	addstr($height+2, $width/6*$_, $_+1) for grep exists $menu[$_], 0..5;
+sub showmenu() {
+	clrtoeol($height+2, 1);
+	my $nr = 0;
+	for (grep exists $menu[$_], $menumin+1..$menumin+$set{menushow}) {
+		my $sub = (my $s = $menu[$_]) =~ s/>\d+$//;
+		addstr($height+2, $width/$set{menushow}*($nr++), $_);
+		attron(A_REVERSE);
+		addstr($s);
+		attroff(A_REVERSE);
+		addch('>') if $sub;
+	} # display menu txts
 } # showmenu
 
-my %falias = (
-	chr(27).chr(79).chr(80)                  =>  0, # F1
-	chr(27).chr(79).chr(81)                  =>  1, # F2
-	chr(27).chr(79).chr(82)                  =>  2, # F3
-	chr(27).chr(79).chr(83)                  =>  3, # F4
-	chr(27).chr(91).chr(49).chr(53).chr(126) =>  4, # F5
-	chr(27).chr(91).chr(49).chr(55).chr(126) =>  5, # F6
-	chr(27).chr(91).chr(49).chr(56).chr(126) =>  6, # F7
-	chr(27).chr(91).chr(49).chr(57).chr(126) =>  7, # F8
-	chr(27).chr(91).chr(50).chr(48).chr(126) =>  8, # F9
-	chr(27).chr(91).chr(50).chr(49).chr(126) =>  9, # F10
-	chr(27).chr(91).chr(50).chr(51).chr(126) => 10, # F11
-	chr(27).chr(91).chr(50).chr(52).chr(126) => 10, # F12
-); # %falias
-
-my %alias = (
-	q     => chr 4,   # quit
-	s     => 'sin',
-	c     => 'cos',
-	t     => 'tan',
-	l     => 'log',
-	x     => 'xroot',
-	chr 8 => chr 127, # backspace
-); # %alias
-
-my %action = (
-	chr 13 => sub {
-		unshift @stack, $stack[0];
-		$nopush = 1;
-	}, # duplication
-
-	'+' => sub {
-		$stack[1] += shift @stack;
-	}, # addition
-	'-' => sub {
-		$stack[1] -= shift @stack;
-	}, # substraction
-	'*' => sub {
-		$stack[1] *= shift @stack;
-	}, # multiplication
-	'/' => sub {
-		$stack[1] /= shift @stack;
-	}, # division
-	'%' => sub {
-		$stack[1] %= shift @stack;
-	}, # modulus
-
-	'^' => sub {
-		$stack[1] **= shift @stack;
-	}, # exponentiation
-	'xroot' => sub {
-		$stack[1] **= 1/shift @stack;
-	}, # x-root of y
-
-	'&' => sub {
-		$stack[1] &= shift @stack;
-	}, # bitwise and
-	'|' => sub {
-		$stack[1] |= shift @stack;
-	}, # bitwise or
-	'#' => sub {
-		$stack[1] ^= shift @stack;
-	}, # bitwise xor
-	'~' => sub {
-		unshift @stack, ~(shift @stack);
-	}, # bitwise not
-
-	'log' => sub {
-		unshift @stack, log shift @stack;
-	}, # logarithm
-	'alog' => sub {
-		unshift @stack, 10 ** shift @stack;
-	}, # 10^x
-
-	'sin' => sub {
-		unshift @stack, sin shift @stack;
-	}, # sine
-	'cos' => sub {
-		unshift @stack, cos shift @stack;
-	}, # cosine
-	'tan' => sub {
-		local $_ = shift @stack;
-		unshift @stack, sin($_) / cos($_);
-	}, # tangent
-
-	'abs' => sub {
-		unshift @stack, abs shift @stack;
-	}, # absolute
-	'_' => sub {
-		unshift @stack, -shift @stack;
-	}, # negative
-	'min' => sub {
-		local $_ = shift @stack;
-		$stack[1] = $_ if $_<$stack[1];
-	}, # minimum
-
-	'dec' => sub {
-		$base = 10;
-	}, # decimal
-	'bin' => sub {
-		$base = 2;
-	}, # binary
-	'oct' => sub {
-		$base = 8;
-	}, # octal
-	'hex' => sub {
-		$base = 16;
-	}, # hexadecimal
-	'base36' => sub {
-		$base = 36;
-	}, # alphanumerical
-); # %action
 
+DRAW:
 clear;
-showmenu(0);
+showmenu();
+showstack();
 addstr($height+1, 0, "> ");
 
 while (1) {
-	addstr($height+1, 2, showval($val[0], $base));
+	addstr($height+1, 2, showval($val{i}, $set{base}));
+	addstr('_'.$val{unit}{name}) if exists $val{unit};
+	addstr($val{bla}) if exists $val{bla};
 	clrtoeol;
 	refresh;
 
@@ -194,54 +405,70 @@ while (1) {
 		while (defined (my $key = ReadKey -1)) {
 			$_ .= $key;
 		} # read additional keys
-	} # escape
+	} # escape sequence
 
 	exists $alias{$_}  and $_ = $alias{$_};
 	exists $falias{$_} and $_ = $menu[$falias{$_}];
 
-	if ($_ eq chr 4) {
-		last INIT;
-	} # ^D
-	elsif ($_ eq chr 27) {
-		redo INIT;
-	} # escape
-
-	elsif (/^[\d.]$/) {
-		unshift @stack, $val[0] and showstack() unless $nopush;
-		@val = (0, 0) if $nopush<2; # replace current
-		$nopush = 2;
-		if ($_ eq '.') {
-			$val[1] = 1;
-		} # dot
-		elsif ($val[1] *= 10) {
-			$val[0] += $_/$val[1];
-		} # fraction
-		else {
-			$val[0] = $val[0]*10+$_;
-		} # integer
-	} # number
-	elsif ($_ eq chr 127) {
-		if ($val[1] = int $val[1]/10) {
-			$val[0] = int($val[0]*$val[1])/$val[1];
-		} else {
-			$val[0] = int $val[0]/10
+	$_ = delete $val{bla} if exists $val{bla} and $_ eq ' ';
+
+	if ($_ eq 'quit') {
+		last;
+	} # quit
+	elsif ($_ eq 'refresh') {
+		goto DRAW;
+	} # refresh
+
+	elsif (/>(\d+)$/) {
+		@menu = @{ $menus[$1] };
+		$menumin = 0;
+		showmenu();
+	} # submenu
+
+	elsif (exists $val{bla} or /^[A-Z]$/) {
+		if (defined $val{i}) {
+			unshift @stack, $val{i};
+			%val = (i=>undef, frac=>0);
+			showstack();
 		}
-	} # backspace
-
-	elsif (exists $action{$_}) {
-		unshift @stack, $val[0];
-		$nopush = 0;
-		$action{$_}();
-		$val[0] = shift @stack;
-		showstack();
+		$val{bla} .= lc $_;
+	} # manual command
+
+	elsif (exists $action{$_} or /^\d$/) {
+		my ($type, $cmd) = @{ $action{$_} || $action{digit} };
+		if ($type==-2) {
+			$val{i} = 0 unless defined $val{i};
+		} # modify value
+		if ($type>0 and defined $val{i}) {
+			unshift @stack, $val{i};
+			%val = (i=>undef, frac=>0);
+		} # auto enter
+		$cmd->();
+		showstack() if $type>=0;
 	} # some operation
 
+	elsif ($_ =~ /^_/) {{
+		$_ = $unit{substr $_, 1} or next;
+		if (exists $val{unit} and $val{unit}{type}==$_->{type}) {
+			unshift @stack, $val{i} and showstack() if defined $val{i};
+			$stack[0] *= delete($val{unit})->{val} / $_->{val};
+			%val = (i=>undef, frac=>0);
+		} # convert
+		else {
+			$val{unit} = $_;
+		} # set source unit
+	}} # conversion
+
 	else {
-		print "\n* error: ", join(' ', map ord, split //, $_), "\n";
-	}
-} # input loop
-}
+		attron(A_REVERSE);
+		addstr($height+1, 0, "* error: ".join(' ', map ord, split //, $_)." *");
+		attroff(A_REVERSE);
+		clrtoeol;
+		refresh;
 
-ReadMode 0;
-endwin;
+		ReadKey; # wait for confirm
+		1 while defined (ReadKey -1); # clear key buffer
+		goto DRAW; # screen messed up
+	} # error
+} # input loop