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<color-chooser></color-chooser>
.base-colors li { float: left; padding: 5px; margin: 0px; border: solid 2px white;}
.base-colors {list-style: none;}
.clear {clear: both;}
.final-colors li { float: left; padding: 5px; margin: 0px; width: 40px;border: solid 2px white;}
.final-colors {list-style: none; width: 330px;}
.final {
width: 100px;
height: 100px;
margin: 40px;
}
li.selected {
border: solid 2px black;
}
import {Component} from "//unpkg.com/can@5/core.mjs";
Component.extend({
tag: "color-chooser",
view: `
<div>Click to lock base color
<span style="{{ this.colorStyle(this.baseOrSuggestedColor) }}">
{{ this.printShortColor(this.baseOrSuggestedColor) }}
</span>
</div>
<ul class='base-colors'>
{{# for(color of this.baseColors) }}
<li style="{{ this.colorStyle(color) }}"
on:click="this.selectBaseColor(color)"
on:mouseenter="this.suggestBaseColor(color)"
{{# eq(color, baseColor) }}class='selected'{{/ eq }}>
R{{color.red}}<br/>
G{{color.green}}<br/>
B{{color.green}}
</li>
{{/for}}
</ul>
<div class='clear'>
Click to lock final color
<span style="{{ colorStyle(this.finalOrBaseOrSuggestedColor) }}">
{{ printShortColor(this.finalOrBaseOrSuggestedColor) }}
</span>
</div>
<ul class='final-colors'>
{{# for(color of this.finalColors) }}
<li style="{{ colorStyle(color) }}"
on:click="selectFinalColor(color)"
on:mouseenter="suggestFinalColor(color)"
{{#eq(color,this.finalColor)}}class='selected'{{/eq}}>
R{{color.red}}<br/>
G{{color.green}}<br/>
B{{color.green}}
</li>
{{/ for }}
</ul>
<div class='final clear'
style="{{ this.colorStyle(this.finalOrBaseOrSuggestedColor) }}">
FINAL COLOR
{{ this.printShortColor(this.finalOrBaseOrSuggestedColor) }}
</div>
`,
ViewModel: {
// STATEFUL PROPS
baseCols: {default: 19},
suggestedBaseColor: "any",
baseColor: "any",
suggestedFinalColor: "any",
finalColor: "any",
// DERIVED VALUES
get baseColors(){
const sinFreq = .3;
const greenPhase = 2 * Math.PI / 3;
const bluePhase = 4 * Math.PI / 3;
const sineWidth = 127;
const sineCtr = 128;
const colors = [];
for (let j = 0; j < this.baseCols; ++j) {
var red = Math.round(Math.sin(sinFreq * j + 0) * sineWidth + sineCtr);
var green = Math.round(Math.sin(sinFreq * j + greenPhase) * sineWidth + sineCtr);
var blue = Math.round(Math.sin(sinFreq * j + bluePhase) * sineWidth + sineCtr);
colors.push({red, green, blue})
}
return colors;
},
get lastBaseColor(){
return this.baseColors[this.baseColors.length-1];
},
get baseOrSuggestedColor(){
return this.baseColor || this.suggestedBaseColor || this.lastBaseColor;
},
get finalOrBaseOrSuggestedColor(){
return this.finalColor || this.suggestedFinalColor || this.baseOrSuggestedColor;
},
get finalColors() {
var baseOrSuggestedColor = this.baseOrSuggestedColor;
var cols = 6;
var finalColors = [];
for(var c = 0; c < cols; c++) {
for(var r = 0 ; r < cols; r++) {
let xOffset = 3 - c; // How far am I from grid center?
let yOffset = 3 - r;
// Purely empirical way of getting a useful range:
let red = baseOrSuggestedColor.red + xOffset * 19 + yOffset * 43;
let green = baseOrSuggestedColor.green + xOffset * 19 + yOffset * 43;
let blue = baseOrSuggestedColor.blue + xOffset * 19 + yOffset * 43;
red = red > 255 ? 255 : red < 1 ? 0 : red;
green = green > 255 ? 255 : green < 1 ? 0 : green;
blue = blue > 255 ? 255 : blue < 1 ? 0 : blue;
finalColors.push({red, green, blue})
}
}
return finalColors;
},
// HELPER METHODS
colorStyle(color){
return `background-color: rgb(${color.red},${color.green},${color.blue});`
},
printShortColor(color) {
return `${color.red},${color.green},${color.blue}`;
},
// METHODS THAT CHANGE STATE
suggestBaseColor(color) {
this.suggestedBaseColor = color;
},
selectBaseColor(color) {
this.baseColor = color;
// There's less imperitive ways of doing this
this.suggestedFinalColor = null;
this.finalColor = null;
},
suggestFinalColor(color) {
this.suggestedFinalColor = color;
},
selectFinalColor(color) {
this.finalColor = color;
}
}
});
Also see: Tab Triggers