Backdrops that need no drawing

A backdrop is a picture the graphics card makes by itself. It is behind whatever you draw, and shows wherever you have left the canvas clear: wipe the picture each frame with background() (no colour) and do not paint a colour over it.

15 of the 94 effects: plasma, starfield, metaballs, flow, warp, voronoi, moire, interference, aurora, fire, clouds, matrixRain, copperBars, checkerFloor, twister.

Each is one line to turn on. The value in the brackets is the one a plain number (or name) sets, and every other setting goes in by name: glow(0.8, { radius: 40 }), or in Python glow(0.8, radius=40). Every effect also has amount, from 0 to 1: how much of it is mixed in.

plasma

Slow rolling colour.

JavaScriptPython
plasma("sunset")plasma("sunset")
SettingIn PythonStarts atCan be
palettepalette"sunset"a palette's name, or a list of colours
speedspeed0.3-5 to 5
scalescale10.1 to 10
amountamount10 to 1

starfield

Flying through stars.

JavaScriptPython
starfield(0.5)starfield(0.5)
SettingIn PythonStarts atCan be
speedspeed0.5-5 to 5
starsstars10 to 4
colourcolour"white"any colour
xxthe middlea place in the scene
yythe middlea place in the scene
amountamount10 to 1

metaballs

Blobs that melt into each other when they meet: a lava lamp.

JavaScriptPython
metaballs("neon")metaballs("neon")
SettingIn PythonStarts atCan be
palettepalette"neon"a palette's name, or a list of colours
speedspeed0.5-5 to 5
countcount71 to 12, a whole number
sizesize10.2 to 4
amountamount10 to 1

flow

Colour that folds and curls like ink in water.

JavaScriptPython
flow("ocean")flow("ocean")
SettingIn PythonStarts atCan be
palettepalette"ocean"a palette's name, or a list of colours
speedspeed0.2-5 to 5
scalescale10.1 to 10
amountamount10 to 1

warp

A chequered tunnel rushing past.

JavaScriptPython
warp("neon")warp("neon")
SettingIn PythonStarts atCan be
palettepalette"neon"a palette's name, or a list of colours
speedspeed1-10 to 10
xxthe middlea place in the scene
yythe middlea place in the scene
amountamount10 to 1

voronoi

Soft coloured cells that slowly shift.

JavaScriptPython
voronoi("candy")voronoi("candy")
SettingIn PythonStarts atCan be
palettepalette"candy"a palette's name, or a list of colours
speedspeed0.3-5 to 5
scalescale10.1 to 10
amountamount10 to 1

moire

Two sets of rings crossing, making patterns neither has alone.

JavaScriptPython
moire("white")moire("white")
SettingIn PythonStarts atCan be
colourcolour"white"any colour
speedspeed0.3-5 to 5
scalescale10.1 to 10
amountamount10 to 1

interference

Waves from four moving points, crossing.

JavaScriptPython
interference("ocean")interference("ocean")
SettingIn PythonStarts atCan be
palettepalette"ocean"a palette's name, or a list of colours
speedspeed0.5-5 to 5
scalescale10.1 to 10
amountamount10 to 1

aurora

The northern lights over a night sky.

JavaScriptPython
aurora("aurora")aurora("aurora")
SettingIn PythonStarts atCan be
palettepalette"aurora"a palette's name, or a list of colours
speedspeed0.3-5 to 5
amountamount10 to 1

fire

Flames rising from the bottom of the picture.

JavaScriptPython
fire("fire")fire("fire")
SettingIn PythonStarts atCan be
palettepalette"fire"a palette's name, or a list of colours
speedspeed1-5 to 5
scalescale10.1 to 10
amountamount10 to 1

clouds

A sky with drifting clouds.

JavaScriptPython
clouds("#3a8fdc")clouds("#3a8fdc")
SettingIn PythonStarts atCan be
colourcolour"#3a8fdc"any colour
speedspeed0.1-5 to 5
scalescale10.1 to 10
amountamount10 to 1

matrixRain

Green marks falling in columns.

JavaScriptPython
matrixRain("#3dff7a")matrix_rain("#3dff7a")
SettingIn PythonStarts atCan be
colourcolour"#3dff7a"any colour
speedspeed10 to 10
sizesize146 to 80
amountamount10 to 1

copperBars

Shining bars sliding up and down: a demo-scene classic.

JavaScriptPython
copperBars("rainbow")copper_bars("rainbow")
SettingIn PythonStarts atCan be
palettepalette"rainbow"a palette's name, or a list of colours
countcount51 to 8, a whole number
speedspeed1-5 to 5
sizesize344 to 300
amountamount10 to 1

checkerFloor

A chequered floor rushing towards you under a glowing horizon.

JavaScriptPython
checkerFloor("#ff2a6d")checker_floor("#ff2a6d")
SettingIn PythonStarts atCan be
colourcolour"#ff2a6d"any colour
darkdark"#101a3a"any colour
speedspeed1-10 to 10
amountamount10 to 1

twister

A twisting four-sided bar, another demo-scene classic.

JavaScriptPython
twister("candy")twister("candy")
SettingIn PythonStarts atCan be
palettepalette"candy"a palette's name, or a list of colours
speedspeed1-5 to 5
sizesize0.220.02 to 0.5
amountamount10 to 1