>> energy ball ascii shader

d = dist(x/2+w/4, y, w/2, h/2)
an = angle(x/2+w/4, y, w/2,h/2)+t/4200
r=10.2

if (d < r) lex.bg = randint(r)

ll=abs(an|0)+""
lex.char=ll[ll.length-1]

if (d > r) {
  lex.bg = randint(d)
  lex.fg = randint(d)
  lex.char = ll[ll.length-2]
}


>> original shader..

lex.bg = hue((x+y*y+t/10)/20)
lex.fg = (x+y)%16
lex.char = (y%2) ? ":" : "%" 



>> drifting fire

t += sin(x/1000)*100000
pos = y/h*6 + sin(x*3) - cos(y*t/10000-10)
pos = clamp(pos, 0, 6)
lex.bg = hue(pos)



>> the "bJoel56" shader

yy=y
x-=w/2
y-=h/2

lex.bg = blue(yy/h+random())
lex.fg = green(yy/h*4 + sin(x/100+random()/2)) // hue(t/1000)|0;

var abcd=".'~:;!>+=icjtJYSGSXDQKHNWM";
function chara (aa,n) { return aa[clamp(n*aa.length, 0, aa.length)|0] }
lex.char = chara(abcd, y/h*(5/3 + tan(x/100)+random()/1))



>> noise brushes, works on a black background:

if (lex.bg != 1) lex.bg = max(5, yellow(randint(t)))


>> simple rainbow:

if (lex.bg != 1) lex.bg = randint(t)


>> self-erasing:

if (lex.bg != 1) lex.bg = yellow(randint(t))


>> cycling rainbow brush

if (lex.bg != 1) lex.bg = hue( all_color_hue_order.indexOf( color_names[ lex.bg ] ) + 1 )



>> inelegant way to slow the frame rate of a shader.

window.zz=window.zz||0
if(!(x+y)) zz++
if (lex.bg != 1 && !(zz % 4)) {
  ...
}


>> frog shader v2

t/=-100
d = sinp( (dist(x/2+w/4, y, w/2, h/2) + t)/2 ) * 10

lex.char=',./>"ASE$#'[(floor(d))]
lex.fg = [1,3,9][floor(d*3)%3]
lex.bg=1


>> frog shader v3

// set period to like 0.2 for a normal circle
period = y/10

t/=-100
d = sinp( (dist(x/2+w/4, y, w/2, h/2) + t) * period )
dd = d * 10.5
d3 = dd < 8 ? 0 : 1

lex.char=' .,"+/>OXEN'[(floor(dd))]
lex.fg = [3,9][floor(d3)]
lex.bg=1


many cool shaders are possible with this technique.. changing the char
gradient (lex.char=...) etc. i love how the dots move on v4.

this is a variation that looks like a bunch of ships flying across the screen.
has a really cool 3d look to it cuz the rows move at different speeds.

period = sin(y)

t/=-100
d = sinp( (dist(x/2+w/4, y, w/2, h/2) + t) * period )
dd = d * 10.5
d3 = dd < 8 ? 0 : 1

lex.char=' .,"+/>\^+'[(floor(dd))]
lex.fg = [3,9][floor(d3)]
lex.bg=1


>> "stars" brush.. set your brush to paint just the character "#"

if (lex.char == "#") {
  lex.fg = hue(randint(15))
  lex.char = random() > 0.1 ? " " : "+@*.,\"+'*-"[randint(10)]
}


>> use fg char to mask mask what you're drawing on the bg

if (lex.char != "/") { lex.bg = 1 }


>> concentric circles with a wavy "sunburst" pattern going around them


x -= w/2
y -= h/2

x /= h
y /= h/2 + 2

r = dist(x,y,0,0)
ang = angle(x,y,0,0)

if (r < 0.6) {
  if (abs(mod(sin((r*t)/100000000000) + ang*18,TWO_PI)) < 2)
    lex.bg = 12
  else
    lex.bg = 5
}
else if (r < 0.65)
  lex.bg = 4
else if (abs(mod(sin((r*t)/100000000000) + ang*18,TWO_PI)) < 2)
  lex.bg = 7
else
  lex.bg = 8


>> slash-based interference patterns

if (x > h*2) x=h-x
y-=h/2
t/=2000

if (sin(x-y*t) > 0) {
  lex.bg=1
  lex.fg=4
  lex.char= Math.floor(x-y*10001+t)%2 ? '\/' : '\\' 
}
else {
  lex.bg=1
  lex.fg=9
  lex.char= Math.floor(3*x+y+t)%2 ? '\\' : ' ' 
}


>> sparkling stars

if (lex.char != " ") {
  lex.fg =floor( Math.random()*10 )
  var az="Xx+*"
  lex.char=az[floor(az.indexOf(lex.char)+ t/10000000 +Math.random())%az.length]
}


>> clashing contrast text..

First, make a canvas that's totally white.

Run this shader:

if (lex.bg == 0) {
  lex.bg = ((x)%2) ? 15 : 14
}

Then set your brush to a white square.

Run this shader w/ animate:

if (lex.bg == 0) {
  lex.bg = ((x)%2) ? 0 : 1
}


>> glitch shader - produces odd combinations of fg/bg

lex.char=String.fromCharCode(lex.char.charCodeAt(0)+1)
lex.bg+=7
lex.fg+=5


>> coogi x/y doodle

xx=x
t/=1000
x/=w/2
y/=h/2
y-=1
x-=1
x*=x-sin(y/t)
y*=1

  lex.bg = 1 // gray( sin(x/(y/3-1)+t) + sin(y/4+t) )
  lex.fg = hue( sin((y/5)+t) - cos(x*t) *5 )
  lex.char = " _.,:;\"~|  "[Math.round(xx*(y+1+(x+t/102)/4)*13)%13]


>> dots / lines shader

  xx = ((t/10*x)*y/10)%8
  lex.bg = colors.black
  lex.fg = green(x*3+y*5)
  lex.char = ((xx%1) !== 0) ? " " : " .,;=+!@"[xx]


>> munching squares horizon

t/=100
y+=10
x-=w/2
x/=y/10
lex.bg=hue((x^y)+t)


>> sharded glitch brush

Example: http://asdf.us/z/kksnvs.png 

Use on a brush:

lex.bg = t/y/x
lex.opacity = lex.bg % 1 ? 0 : 1


>> incremental brush

Set your brush to be the ^ character, square, about 10x10
Draw "char" only
Then animate this shader on the canvas:

if (lex.char=="^") {
  lex.bg += 1
  lex.char = " "
}
lex.bg += 1


>> copy color brushes

Set to "animate brush", then use option+shift (alt+shift?) to
copy color from the canvas. Brush will have "shape" of 
copied color only.. can be a cool effect when used with fg/bg only.

lex.opacity = lex.bg == colors.black ? 0 : 1


>> distressed texture brush

Sample use of the "choice" function to get a random color.

var char = choice("      abcdef      ")
lex.bg = +choice("0124")
lex.fg = +choice("01234")
lex.char = char
lex.opacity = char == " " ? 0 : 1


>> foggy terrain brush

var char = choice("      abcdef      ")
lex.bg = choice([14,15])
lex.fg = choice("367")
lex.char = char
lex.opacity = char == " " ? 0 : 1


>> mirror brush (left-right)

Animate this on the canvas, then draw:

if (x > w/2) {
  lex.assign( canvas.aa[y][w-x] )
}


>> mirror brush (up-down)

if (x > h/2) {
  lex.assign( canvas.aa[h-y][x] )
}