Shaders
Shader code, drawn in characters as you type. A fragment shader runs on the graphics card and is redrawn in Unscii characters every frame. The code recompiles as you type; Shadertoy shaders with one pass paste in as they are.
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Compiling
Inputs: iTime, iResolution, iMouse (drag the picture), iFrame, iDate, and iChannel0 to 3, a noise texture. Ctrl or Cmd and Enter compiles at once. Ctrl or Cmd and E shows or hides the code; F fills the screen.