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Implement shading without alpha channel #5

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Implement shading without alpha channel #5

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132 changes: 86 additions & 46 deletions versions/version3/version3.js
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Original file line number Diff line number Diff line change
@@ -1,44 +1,71 @@
const DEFAULT_OPTIONS = {
initialColor: "#e4e6e3",
secondColor: "#6cfe6b",
settledColor: "#00dd00",
bold: true,
shading: true,
fontSize: 20,
minLength: 5,
maxLength: 20,
slowestInterval: 500,
fastestInterval: 50,
columnWidthTweak: 0.85,
totalStreamMultiplier: 1,
};

const CHARACTERS =
"MATRIXMATRIXMATRIXMATRIXMAØ1Ø1Ø1Ø1Ø#$%@&#$%@&ｦｧｨｩｪｫｬｭｮｯｱｲｳｴｵｶｷｸｹｺｻｼｽｾｿﾀﾁﾂﾃﾄﾅﾇﾈﾉﾊﾋﾌﾍﾎﾏﾐﾑﾒﾓﾔﾕﾖﾗﾘﾙﾚﾛﾜﾝｦｧｨｩｪｫｬｭｮｯｱｲｳｴｵｶｷｸｹｺｻｼｽｾｿﾀﾁﾂﾃﾄﾅﾇﾈﾉﾊﾋﾌﾍﾎﾏﾐﾑﾒﾓﾔﾕﾖﾗﾘﾙﾚﾛﾜﾝｦｧｨｩｪｫｬｭｮｯｱｲｳｴｵｶｷｸｹｺｻｼｽｾｿﾀﾁﾂﾃﾄﾅﾇﾈﾉﾊﾋﾌﾍﾎﾏﾐﾑﾒﾓﾔﾕﾖﾗﾘﾙﾚﾛﾜﾝｦｧｨｩｪｫｬｭｮｯｱｲｳｴｵｶｷｸｹｺｻｼｽｾｿﾀﾁﾂﾃﾄﾅﾇﾈﾉﾊﾋﾌﾍﾎﾏﾐﾑﾒﾓﾔﾕﾖﾗﾘﾙﾚﾛﾜﾝ";

const getRandomChar = () => {
const randNum = Math.floor(Math.random() * CHARACTERS.length);
return CHARACTERS.charAt(randNum);
};
Comment on lines +16 to +22
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Refactor 2: Extract characters and getRandomChar outside of the DigitalRain class.


const parseHex = (hex) => {
const colorRegex = /^#?([a-f\d]{2})([a-f\d]{2})([a-f\d]{2})$/i;
const [, red, green, blue] = hex.match(colorRegex);
return {
red: parseInt(red, 16),
green: parseInt(green, 16),
blue: parseInt(blue, 16),
};
};

const multiplyRgb = (rgb, multiplier) => {
return {
red: Math.floor(rgb.red * multiplier),
blue: Math.floor(rgb.blue * multiplier),
green: Math.floor(rgb.green * multiplier),
};
};

function rgbToHex(rgb) {
// Convert the values to hex strings and return the concatenated string
return `#${rgb.red.toString(16).padStart(2, "0")}${rgb.green
.toString(16)
.padStart(2, "0")}${rgb.blue.toString(16).padStart(2, "0")}`;
}

class DigitalRain {
constructor(canvasContainer) {
constructor(canvasContainer, options) {
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Refactor 1: let the constructor take in an optional parameter options.

this.canvasContainer = canvasContainer;
this.canvas = null;
this.canvas2 = null;
this.ctx = null;
this.ctx2 = null;
Object.assign(this, { ...DEFAULT_OPTIONS, ...options });

this.resizeTimer;

this.animationMode = "requestAnimationFrame";

this.characters =
"MATRIXMATRIXMATRIXMATRIXMAØ1Ø1Ø1Ø1Ø#$%@&#$%@&ｦｧｨｩｪｫｬｭｮｯｱｲｳｴｵｶｷｸｹｺｻｼｽｾｿﾀﾁﾂﾃﾄﾅﾇﾈﾉﾊﾋﾌﾍﾎﾏﾐﾑﾒﾓﾔﾕﾖﾗﾘﾙﾚﾛﾜﾝｦｧｨｩｪｫｬｭｮｯｱｲｳｴｵｶｷｸｹｺｻｼｽｾｿﾀﾁﾂﾃﾄﾅﾇﾈﾉﾊﾋﾌﾍﾎﾏﾐﾑﾒﾓﾔﾕﾖﾗﾘﾙﾚﾛﾜﾝｦｧｨｩｪｫｬｭｮｯｱｲｳｴｵｶｷｸｹｺｻｼｽｾｿﾀﾁﾂﾃﾄﾅﾇﾈﾉﾊﾋﾌﾍﾎﾏﾐﾑﾒﾓﾔﾕﾖﾗﾘﾙﾚﾛﾜﾝｦｧｨｩｪｫｬｭｮｯｱｲｳｴｵｶｷｸｹｺｻｼｽｾｿﾀﾁﾂﾃﾄﾅﾇﾈﾉﾊﾋﾌﾍﾎﾏﾐﾑﾒﾓﾔﾕﾖﾗﾘﾙﾚﾛﾜﾝ";

this.initialColor = "#e4e6e3";
this.secondColor = "#6cfe6b";
this.settledColor = "#00dd00";

this.bold = true;
this.shading = true;

this.fontSize = 20;

this.minLength = 5;
this.maxLength = 20;

this.slowestInterval = 500;
this.fastestInterval = 50;

this.rampUp = 15000;

this.totalIntervals = 100;
this.totalStreamControllers = 100;

this.columnWidthTweak = 0.85;

this.totalStreams = null;

this.totalStreamMultiplier = 1;

// Perhaps we could check if the user has a stored
// "themes" object we can load, if not load defaults
this.themes = [
Expand Down Expand Up @@ -311,36 +338,51 @@ class DigitalRain {
);
};

const textTweak = (context, character, xloc, yloc, charPos) => {
const textTweak = (context, character, xloc, yloc, charPos, color) => {
const originalStyle = context.fillStyle;
if (color != null) {
context.fillStyle = color;
}
context.fillText(
character,
Math.floor(xloc),
Math.floor(yloc - this.fontSize * charPos),
rectTrim
);
};

const getRandomChar = () => {
const randNum = Math.floor(Math.random() * this.characters.length);
return this.characters.charAt(randNum);
context.fillStyle = originalStyle;
};

/*
Think of the end of the stream being at the top of the code here...
*/

// Clean up at the end of the stream
this.ctx2.fillStyle = "black";
fillRectTweak(this.ctx2, stream.XLOC, stream.YLOC, stream.streamLength);
if (stream.characters.length > stream.streamLength) {
stream.characters.pop();
}
// this.ctx2.fillStyle = "black";
// fillRectTweak(this.ctx2, stream.XLOC, stream.YLOC, stream.streamLength);
this.ctx.fillStyle = "black";
fillRectTweak(this.ctx, stream.XLOC, stream.YLOC, stream.streamLength);

// Shading with rgba() is detrimental to performance because
// the browser has to calculate the blending on each draw
if (this.shading) {
for (let i = 4; i < stream.streamLength - 3; i++) {
this.ctx2.fillStyle = "rgba(0, 0, 0, 0.075)";
fillRectTweak(this.ctx2, stream.XLOC, stream.YLOC, i);
for (let i = 4; i < stream.characters.length; i++) {
const char = stream.characters[i];
const settledRgb = parseHex(this.settledColor);
const multiplier = 1 - (i + 1) / stream.streamLength;
const shadedRgb = multiplyRgb(settledRgb, multiplier);
const shadedColor = rgbToHex(shadedRgb);
clearRectTweak(this.ctx, stream.XLOC, stream.YLOC, i + 1);
textTweak(
this.ctx,
char,
stream.XLOC,
stream.YLOC,
i + 1,
shadedColor
);
Comment on lines -341 to +385
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Alternative way of implementing the gradient shadow effect. This should be more performant because this approach does not use alpha channel.

}
}

Expand All @@ -356,23 +398,22 @@ class DigitalRain {
}

// Third character
if (stream.secondChar) {
if (stream.characters.length > 1) {
this.ctx.fillStyle = "black";
fillRectTweak(this.ctx, stream.XLOC, stream.YLOC, 2);

this.ctx.fillStyle = `${this.settledColor}`;
textTweak(this.ctx, stream.secondChar, stream.XLOC, stream.YLOC, 2);
textTweak(this.ctx, stream.characters[1], stream.XLOC, stream.YLOC, 2);
}

// Second Character
if (stream.firstChar) {
if (stream.characters.length > 0) {
// Clear square to clean glow from first char
this.ctx.fillStyle = "black";
fillRectTweak(this.ctx, stream.XLOC, stream.YLOC, 1);

this.ctx.fillStyle = `${this.secondColor}`;
textTweak(this.ctx, stream.firstChar, stream.XLOC, stream.YLOC, 1);
stream.secondChar = stream.firstChar;
textTweak(this.ctx, stream.characters[0], stream.XLOC, stream.YLOC, 1);
}

// Paint area for new character black
Expand All @@ -383,10 +424,11 @@ class DigitalRain {
clearRectTweak(this.ctx2, stream.XLOC, stream.YLOC, 0);

// First (new) character
const randNum = Math.floor(Math.random() * this.characters.length);
stream.firstChar = this.characters.charAt(randNum);
const randNum = Math.floor(Math.random() * CHARACTERS.length);
const newChar = CHARACTERS.charAt(randNum);
stream.characters.unshift(newChar);
this.ctx.fillStyle = `${this.initialColor}`;
textTweak(this.ctx, stream.firstChar, stream.XLOC, stream.YLOC, 0);
textTweak(this.ctx, newChar, stream.XLOC, stream.YLOC, 0);

// Set YLOC for next draw interval...
// ... or send to top if entire stream off page
Expand Down Expand Up @@ -558,16 +600,14 @@ class Stream {
this.XLOC = xloc;
this.YLOC = yloc;
this.streamLength = randomStreamLength;
this.firstChar = null;
this.secondChar = null;
this.characters = [];
}

reset(xloc, yloc, randomStreamLength) {
this.XLOC = xloc;
this.YLOC = yloc;
this.streamLength = randomStreamLength;
this.firstChar = null;
this.secondChar = null;
this.characters = [];
Comment on lines -569 to +610
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Refactor 3: Replace firstChar & secondChar with characters.

}
}

Expand Down