30 lines
No EOL
900 B
JavaScript
30 lines
No EOL
900 B
JavaScript
const birdElem = document.querySelector( "[data-bird]" )
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const BIRD_SPEED = 0.5
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const JUMP_DURATION = 150
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let timeSinceLastJump = Number.POSITIVE_INFINITY
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const setTop = ( top ) => birdElem.style.setProperty( "--bird-top", top )
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const getTop = () => parseFloat( getComputedStyle( birdElem ).getPropertyValue( "--bird-top" ) )
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const handleJump = ( event ) => {
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if ( event.code === "Space" ) timeSinceLastJump = 0
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}
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export const setupBird = () => {
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setTop( window.innerHeight / 2 )
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document.removeEventListener( "keydown", handleJump )
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document.addEventListener( "keydown", handleJump )
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}
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export const updateBird = ( delta ) => {
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if ( timeSinceLastJump < JUMP_DURATION )
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setTop( getTop() - BIRD_SPEED * delta )
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else
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setTop( getTop() + BIRD_SPEED * delta )
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timeSinceLastJump += delta
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}
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export const getBirdRect = () => birdElem.getBoundingClientRect() |