Gridworm background canvas demo style body width 600 height 600 style canvas id gridwormCanvas width 600 height 620 style background color white canvas script class GridWorm constructor point interval pointsList screenWidth screenHeight this radius 2 this xCoord point x this yCoord point y this interval interval this color this getColor 1 true get random color object this mainColor this color color color of the head and body of the girdworm this mainColorIndex this color index this nColor this getColor 1 true get another random color object this arrowHeadColor this nColor color color of the arrrow points at the head of the gridworm this arrowHeadColorIndex this nColor index this pointsList pointsList this screenWidth screenWidth this screenHeight screenHeight this speed 5 the magnitude of the velocity this velocity this getVelocity this junctionMemory point point velocity this velocity memory of each junction visited helps to construct the worm the maximum number of junctions a gridworm can keep in memory this determines how long the gridworm will be this junctionMemoryLength 6 getColor opacity isRandom true index 0 if opacity 0 opacity 1 opacity null isNaN opacity if opacity is incorrect opacity 1 var colors rgba 0 0 0 opacity rgba 192 192 192 opacity silver rgba 128 128 128 opacity gray rgba 128 0 0 opacity maroon rgba 255 0 0 opacity red rgba 0 255 0 opacity lime rgba 0 0 255 opacity blue rgba 255 0 255 opacity fuchsia rgba 128 128 0 opacity olive rgba 0 128 0 opacity green rgba 128 0 128 opacity purple rgba 0 128 128 opacity teal rgba 0 0 128 opacity navy rgba 138 57 0 opacity brown rgba 205 133 63 opacity rgba 244 164 96 opacity rgba 139 105 30 opacity rgba 165 42 42 opacity rgba 178 34 34 opacity rgba 220 20 60 opacity rgba 255 140 0 opacity rgba 255 165 0 opacity rgba 255 215 0 opacity rgba 184 134 11 opacity rgba 218 165 32 opacity rgba 218 165 32 opacity rgba 238 232 170 opacity rgba 189 183 107 opacity rgba 240 230 140 opacity rgba 0 100 0 opacity rgba 34 139 34 opacity rgba 32 178 170 opacity rgba 47 79 79 opacity rgba 0 139 139 opacity rgba 95 158 160 opacity rgba 70 130 180 opacity rgba 25 25 112 opacity rgba 0 0 128 opacity rgba 0 0 139 opacity rgba 72 61 139 opacity rgba 75 0 130 opacity rgba 139 0 139 opacity rgba 0 0 0 opacity rgba 105 105 105 opacity rgba 169 169 169 opacity if isRandom let index Math floor this getRandomNumber 0 colors length 1 let color colors index return color color index index else if specific if index 0 index colors length return colors index return colors 0 getVelocity let x y flip a coin to decide if gridworm moves vertically or horizontally if Math random 0 5 if gridworm moves vertically x 0 no horizontal movement y Math random 0 5 this speed this speed flip a coin to decide if gridworm moves upwards or downwards else if gridworm moves horizontally x Math random 0 5 this speed this speed flip a coin to decide if gridworm moves left or right y 0 no vertical movement return x x y y Returns a random number between min inclusive and max exclusive param number min The lesser of the two numbers param number max The greater of the two numbers return number A random number between min inclusive and max exclusive getRandomNumber min max return Math random max min min drawCircle x y circleradius ctx colorIndex for let i 0 i 3 i let color let radius 0 switch i create three circles with same center case 0 radius circleradius smallest circle color this getColor 1 false colorIndex break case 1 radius circleradius 2 bigger circle color this getColor 0 5 false colorIndex break case 2 radius circleradius 6 biggest circle color this getColor 0 2 false colorIndex break draw the node ctx beginPath ctx arc x y radius 0 2 Math PI ctx fillStyle color ctx fill ctx strokeStyle color ctx stroke drawArrowHead x y circleradius ctx colorIndex let points if this velocity x 0 if gridworm is moving vertically if this velocity y 0 if gridworm is moving down points push x x this interval 3 y y point to the right points push x x this interval 3 y y point to the left points push x x y y this interval 3 point below else if gridworm is moving up points push x x this interval 3 y y point to the right points push x x this interval 3 y y point to the left points push x x y y this interval 3 point above else if gridworm is moving horizontally if this velocity x 0 if gridworm is moving right points push x x this interval 3 y y point to the right points push x x y y this interval 3 point above points push x x y y this interval 3 point below else if gridworm is moving left points push x x this interval 3 y y point to the left points push x x y y this interval 3 point above points push x x y y this interval 3 point below draw a circle about the points that make the arrow head for let i 0 i points length i let point points i this drawCircle point x point y circleradius 2 ctx colorIndex this drawTriangle points 0 points 1 points 2 ctx draw the arrow head drawTriangle point1 point2 point3 ctx ctx beginPath ctx moveTo point1 x point1 y ctx lineTo point2 x point2 y ctx lineTo point3 x point3 y ctx fillStyle rgba 0 0 0 0 1 transparent black ctx fill draw ctx draw the head of the gridworm this drawCircle this xCoord this yCoord this radius 2 ctx this mainColorIndex this drawArrowHead this xCoord this yCoord this radius 2 ctx this arrowHeadColorIndex draw circles and squares at every visited junctions in the gridworm s memory not RAM for let i 0 i this junctionMemory length i let junction this junctionMemory this junctionMemory length i 1 draw a circle at each junction point this drawCircle junction point x junction point y this radius 2 ctx this mainColorIndex draw painted squares at every junction point ctx fillStyle this getColor 0 1 false this mainColorIndex ctx fillRect junction point x junction point y this interval this interval draw the line connecting head to body ctx strokeStyle black ctx lineWidth this radius ctx beginPath ctx moveTo this xCoord this yCoord draw a line to link all the visited junctions in the gridworm s memory not RAM for let i 0 i this junctionMemory length i starting from the most recent to the least recent LIFO NB more like a stack data structure let junction this junctionMemory this junctionMemory length i 1 ctx lineTo junction point x junction point y ctx stroke ctx closePath update deltaTime this junctionMemoryLength this junctionMemoryLength 1 1 this junctionMemoryLength keep the gridworm moving in its current direction this xCoord this velocity x if gridworm is going left or right keep it going this yCoord this velocity y if gridworm is going up or down keep it going if this xCoord this interval if gridworm reaches the leftmost point this xCoord this interval this velocity x this velocity x move right this xCoord this velocity x 3 nudge it a bit away from the edge if this xCoord this screenWidth this interval if gridworm reaches the rightmost point this xCoord this junctionMemory this junctionMemory length 1 point x this velocity x this velocity x move left this xCoord this velocity x 3 nudge it a bit away from the edge if this yCoord this interval if gridworm reaches the topmost most point this yCoord this interval this velocity y this velocity y move down this yCoord this velocity y 3 nudge it a bit away from the edge if this yCoord this screenHeight this interval if gridworm reaches the lowest point this yCoord this junctionMemory this junctionMemory length 1 point y this velocity y this velocity y move up this yCoord this velocity y 4 nudge it a bit away from the edge let currentCoord x this xCoord y this yCoord let latestJunction this getJunctionReached currentCoord if latestJunction currentCoord let originalVelocity this velocity let newVelocity this getVelocity flip a coin to decide to move up and down or right and left if originalVelocity y 0 if gridworm is moving horizontally this velocity newVelocity if newVelocity y 0 newVelocity x originalVelocity x if it continues the horizontal movement in the opposite direction don t add the new junction to the memory queue else let memory point latestJunction velocity this velocity if this isInMemory memory this junctionMemory push memory add new memory to the queue this junctionMemory push point latestJunction velocity this velocity add new memory to the queue nudge it a bit away from the junction this xCoord this velocity x 3 not complete yet Don t make it too much or too little else if gridworm is moving vertically this velocity newVelocity if newVelocity x 0 newVelocity y originalVelocity y if it continues the verticalal movement in the opposite direction don t add the new junction to the memory queue else let memory point latestJunction velocity this velocity if this isInMemory memory this junctionMemory push memory add new memory to the queue nudge it a bit away from the junction this yCoord this velocity y 3 not complete yet Don t make it too much or too little if this junctionMemory length this junctionMemoryLength if memory is too long this junctionMemory shift remove the first memory isInMemory memory check if a junction is in memory this junctionMemory some function mem if mem point memory point return true junction is in memory return mem point memory point return false junction is NOT in memory getJunctionReached currentCoord for let i 0 i this pointsList length i let point this pointsList i if point junction is too far away ignore it if Math abs currentCoord x point x 2 this interval Math abs currentCoord y point y 2 this interval continue let distance this getDistance currentCoord point if distance this radius if gridworm head is close enough to a junction return point return currentCoord getDistance p1 p2 the distance between two points p1 and p2 let dx p1 x p2 x let dy p1 y p2 y let distance Math sqrt dx dx dy dy return distance Let node correspond to window resizing param number screenHeight The height of the screen param number screenWidth The width of the screen param number dy The percentage change in browser window height param number dx The percentage change in browser window width refreshScreenSize screenHeight screenWidth dx dy points sets up and controls all points and gridworms on the canvas class Painter constructor screenWidth screenHeight this screenWidth screenWidth this screenHeight screenHeight this interval 40 interval from one point to the next this points this createPoints coordinates of the vertices of all squares when the canvas is partitioned this gridWorms this createGridWorms this color this getRandomColor 0 1 document addEventListener click event when user clicks on the canvas this points this createPoints this gridWorms this createGridWorms spawn new gridworms this color this getRandomColor 0 1 createGridWorms let gridworms numOfGridWorms 10 for var i 0 i numOfGridWorms i let point this points Math floor this getRandomNumber 0 this points length 1 randomly select a point gridworms push new GridWorm point this interval this points this screenWidth this screenHeight return gridworms createPoints divide the canvas into squares let points interval this interval interval from one point to the next for var y interval y this screenHeight y interval get all points in the grid starting from the top to the bottom if y interval this screenHeight if the next point is beyond the right edge of the canvas continue skip for var x interval x this screenWidth x interval all the while getting all the horizontal points at each level if x interval this screenWidth if the next point is beyond the bottom edge of the canvas continue skip points push x x y y return points getRandomColor opacity var colors rgba 255 0 0 opacity red rgba 255 242 0 opacity yellow rgba 0 0 255 opacity blue rgba 255 255 0 opacity yellow rgba 0 255 255 opacity cyan rgba 255 0 255 opacity magenta fuchsia rgba 192 192 192 opacity silver rgba 128 128 128 opacity gray rgba 128 0 0 opacity maroon rgba 128 128 0 opacity olive rgba 0 128 0 opacity green rgba 128 0 128 opacity purple rgba 0 128 128 opacity teal rgba 0 0 128 opacity navy rgba 0 255 0 opacity green rgba 77 0 255 opacity blue rgba 255 0 140 opacity purple rgba 0 255 0 opacity lime return colors parseInt this getRandomNumber 0 colors length Returns a random number between min inclusive and max exclusive param number min The lesser of the two numbers param number max The greater of the two numbers return number A random number between min inclusive and max exclusive getRandomNumber min max return Math random max min min Let canvas respond to window resizing param number screenHeight The height of the screen param number screenWidth The width of the screen refreshScreenSize screenHeight screenWidth if this screenHeight screenHeight this screenWidth screenWidth if the screen size has changed this screenHeight screenHeight this screenWidth screenWidth this points this createPoints coordinates of the vertices of all squares when the canvas is partitioned this gridWorms this createGridWorms update deltaTime this gridWorms forEach function gridworm gridworm update deltaTime draw ctx for var i 0 i this points length i let point this points i ctx fillStyle Math random 0 5 this color white creates a disco effect ctx fillRect point x point y this interval this interval this gridWorms forEach function gridworm gridworm draw ctx set everything up function getBrowserWindowSize return x 600 y 600 let browserWindowSize getBrowserWindowSize c document getElementById gridwormCanvas ctx c getContext 2d set size of canvas c width browserWindowSize x c height browserWindowSize y let SCREEN_WIDTH browserWindowSize x SCREEN_HEIGHT browserWindowSize y painter new Painter SCREEN_WIDTH SCREEN_HEIGHT lastTime 100 windowSize function onWindowResize called every time the window gets resized windowSize getBrowserWindowSize c width windowSize x c height windowSize y SCREEN_WIDTH windowSize x SCREEN_HEIGHT windowSize y window addEventListener resize onWindowResize function updateCanvas ctx clearRect 0 0 SCREEN_WIDTH SCREEN_HEIGHT ctx fillStyle white ctx fillRect 0 0 SCREEN_WIDTH SCREEN_HEIGHT function doAnimationLoop timestamp updateCanvas painter refreshScreenSize SCREEN_HEIGHT SCREEN_WIDTH let canvas respond to window resizing let deltaTime timestamp lastTime lastTime timestamp painter update deltaTime painter draw ctx requestAnimationFrame doAnimationLoop requestAnimationFrame doAnimationLoop setInterval function updateCanvas painter refreshScreenSize SCREEN_HEIGHT SCREEN_WIDTH let canvas respond to window resizing painter update 0 01 painter draw ctx 50 console log ready script
this velocity y this velocity y move up this yCoord this velocity y 4 nudge it a bit away from the edge let currentCoord x this xCoord y this yCoord let latestJunction this getJunctionReached currentCoord if latestJunction currentCoord let originalVelocity this velocity let newVelocity this getVelocity flip a coin to decide to move up and down or right and left if originalVelocity y 0 if gridworm is moving horizontally this velocity newVelocity if newVelocity y 0 newVelocity x originalVelocity x if it continues the horizontal movement in the opposite direction don t add the new junction to the memory queue else let memory point latestJunction velocity this velocity if this isInMemory memory this junctionMemory push memory add new memory to the queue this junctionMemory push point latestJunction velocity this velocity add new memory to the queue nudge it a bit away from the junction this xCoord this velocity x 3 not complete yet Don t make it too much or too little else if gridworm is moving vertically this velocity newVelocity if newVelocity x 0 newVelocity y originalVelocity y if it continues the verticalal movement in the opposite direction don t add the new junction to the memory queue else let memory point latestJunction velocity this velocity if this isInMemory memory this junctionMemory push memory add new memory to the queue nudge it a bit away from the junction this yCoord this velocity y 3 not complete yet Don t make it too much or too little if this junctionMemory length this junctionMemoryLength if memory is too long this junctionMemory shift remove the first memory isInMemory memory check if a junction is in memory this junctionMemory some function mem if mem point memory point return true junction is in memory return mem point memory point return false junction is NOT in memory getJunctionReached currentCoord for let i 0 i this pointsList length i let point this pointsList i if point junction is too far away ignore it if Math abs currentCoord x point x 2 this interval Math abs currentCoord y point y 2 this interval continue let distance this getDistance currentCoord point if distance this radius if gridworm head is close enough to a junction return point return currentCoord getDistance p1 p2 the distance between two points p1 and p2 let dx p1 x p2 x let dy p1 y p2 y let distance Math sqrt dx dx dy dy return distance Let node correspond to window resizing param number screenHeight The height of the screen param number screenWidth The width of the screen param number dy The percentage change in browser window height param number dx The percentage change in browser window width refreshScreenSize screenHeight screenWidth dx dy points sets up and controls all points and gridworms on the canvas class Painter constructor screenWidth screenHeight this screenWidth screenWidth this screenHeight screenHeight this interval 40 interval from one point to the next this points this createPoints coordinates of the vertices of all squares when the canvas is partitioned this gridWorms this createGridWorms this color this getRandomColor 0 1 document addEventListener click event when user clicks on the canvas this points this createPoints this gridWorms this createGridWorms spawn new gridworms this color this getRandomColor 0 1 createGridWorms let gridworms numOfGridWorms 10 for var i 0 i numOfGridWorms i let point this points Math floor this getRandomNumber 0 this points length 1 randomly select a point gridworms push new GridWorm point this interval this points this screenWidth this screenHeight return gridworms createPoints divide the canvas into squares let points interval this interval interval from one point to the next for var y interval y this screenHeight y interval get all points in the grid starting from the top to the bottom if y interval this screenHeight if the next point is beyond the right edge of the canvas continue skip for var x interval x this screenWidth x interval all the while getting all the horizontal points at each level if x interval this screenWidth if the next point is beyond the bottom edge of the canvas continue skip points push x x y y return points getRandomColor opacity var colors rgba 255 0 0 opacity red rgba 255 242 0 opacity yellow rgba 0 0 255 opacity blue rgba 255 255 0 opacity yellow rgba 0 255 255 opacity cyan rgba 255 0 255 opacity magenta fuchsia rgba 192 192 192 opacity silver rgba 128 128 128 opacity gray rgba 128 0 0 opacity maroon rgba 128 128 0 opacity olive rgba 0 128 0 opacity green rgba 128 0 128 opacity purple rgba 0 128 128 opacity teal rgba 0 0 128 opacity navy rgba 0 255 0 opacity green rgba 77 0 255 opacity blue rgba 255 0 140 opacity purple rgba 0 255 0 opacity lime return colors parseInt this getRandomNumber 0 colors length Returns a random number between min inclusive and max exclusive param number min The lesser of the two numbers param number max The greater of the two numbers return number A random number between min inclusive and max exclusive getRandomNumber min max return Math random max min min Let canvas respond to window resizing param number screenHeight The height of the screen param number screenWidth The width of the screen refreshScreenSize screenHeight screenWidth if this screenHeight screenHeight this screenWidth screenWidth if the screen size has changed this screenHeight screenHeight this screenWidth screenWidth this points this createPoints coordinates of the vertices of all squares when the canvas is partitioned this gridWorms this createGridWorms update deltaTime this gridWorms forEach function gridworm gridworm update deltaTime draw ctx for var i 0 i this points length i let point this points i ctx fillStyle Math random 0 5 this color white creates a disco effect ctx fillRect point x point y this interval this interval this gridWorms forEach function gridworm gridworm draw ctx set everything up function getBrowserWindowSize return x 600 y 600 let browserWindowSize getBrowserWindowSize c document getElementById gridwormCanvas ctx c getContext 2d set size of canvas c width browserWindowSize x c height browserWindowSize y let SCREEN_WIDTH browserWindowSize x SCREEN_HEIGHT browserWindowSize y painter new Painter SCREEN_WIDTH SCREEN_HEIGHT lastTime 100 windowSize function onWindowResize called every time the window gets resized windowSize getBrowserWindowSize c width windowSize x c height windowSize y SCREEN_WIDTH windowSize x SCREEN_HEIGHT windowSize y window addEventListener resize onWindowResize function updateCanvas ctx clearRect 0 0 SCREEN_WIDTH SCREEN_HEIGHT ctx fillStyle white ctx fillRect 0 0 SCREEN_WIDTH SCREEN_HEIGHT function doAnimationLoop timestamp updateCanvas painter refreshScreenSize SCREEN_HEIGHT SCREEN_WIDTH let canvas respond to window resizing let deltaTime timestamp lastTime lastTime timestamp painter update deltaTime painter draw ctx requestAnimationFrame doAnimationLoop requestAnimationFrame doAnimationLoop setInterval function updateCanvas painter refreshScreenSize SCREEN_HEIGHT SCREEN_WIDTH let canvas respond to window resizing painter update 0 01 painter draw ctx 50 console log ready script