inverse lerp — live canvas animation example

motion & easing8+
ball bounce
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ball orbiting a sun
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lerp (smooth follow)
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easing functions
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spring (damped harmonic motion)
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move object to changing point
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quadratic bezier curve
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Bézier curves
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trig, angles & vectors8+
sine curve
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demystify sine and cosine
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find points on a circle
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point object towards another
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distribute around circle
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vector reflection (bounce)
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vector rotation
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angle interpolation (shortest turn)
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collision detection11+
point to circle collision
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point to polygon collision
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rectangle to rectangle collision
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circle to rectangle collision
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circle to circle collision
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line to circle collision
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line to line collision
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line to point collision
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line to rectangle collision
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polygon to polygon collision
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circle field (collision at scale)
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numbers in motion7-
lerp
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inverse lerp
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map range
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clamp
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wrap
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ping pong
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smoothstep
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geometry & shapes8+
get a point on a line
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get line length
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get triangle data from line
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draw star
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draw rectangle (using trig, not rect())
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draw equilateral triangle (from radius and center point)
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get circle from three points
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center on parent
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generative showpieces13+
Fourier epicycles
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Conway's Game of Life
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Perlin noise flow field
full function
Wave interference
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Gravitational lensing
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Orbital precession (GR)
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Phyllotaxis (golden angle)
full function
Murmuration (flocking starlings)
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Sierpinski Triangle
full function
Glitter
full function
Pretty Ring
full function
Sparklies
full function
Klimt-Inspired Swirls
full function
handy helpers7+
degrees to radians
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radians to degrees
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format number with commas
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random integer between
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random number between
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color lerp (RGB vs HSL)
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color families (pick a range by name)
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inverseLerp is lerp run backwards. Feed it a value between 0 and 100 (left) and it answers “how far along is that?” as a 0→1 fraction (right). Handy for turning a raw measurement into progress.