文章目录
- 前言
- 一、view生成分享图片
- 1.组件的封装
- 2.组件的使用
- 3.效果
前言
微信小程序并不支持view直接转绘到画布上，想要实现海报功能必须通过以下4个步骤：
- 通过wx.createCanvasContext创建一个画布
- 在画布上绘制文本、内容、图片
- 在通过wx.canvasToTempFilePath保存到本地路径
- 在通过wx.saveImageToPhotosAlbum保存到相册
一、view生成分享图片
1.组件的封装
项目结构图：
1、dialogModal
代码语言：javascript复制var app = getApp()
Component({
data: {
},
properties: {
isShow: {
type: Boolean,
value: false
},
title: {
type: String,
value: '提示'
},
content: {
type: String,
value: ''
},
cancelText: {
type: String,
value: '取消'
},
confirmText: {
type: String,
value: '确定'
},
isNeedAuth: {
type: Boolean,
value: false
},
cancelType: {
type: String,
value: ''
},
confirmType: {
type: String,
value: ''
}
},
methods: {
preventTouchMove() { },
cancel() {
this.setData({
isShow: false
})
this.triggerEvent('cancel')
},
confirm() {
this.setData({
isShow: false
})
this.triggerEvent('confirm')
}
}
}){
"component": true,
"usingComponents": {}
}<view class="container" wx:if="{{isShow}}" catchtouchmove="preventTouchMove">
<view class="back-model"></view>
<view class="conent-model">
<text class="title">{{title}}</text>
<text class="content">{{content}}</text>
<view class="quickBtn">
<button class="cancel-btn" open-type="{{cancelType}}" bindtap="cancel">{{cancelText}}</button>
<button class="confirm-btn" open-type="{{confirmType}}" bindtap="confirm">{{confirmText}}</button>
</view>
</view>
</view>.container {
width: 100%;
height: 100%;
}
.back-model {
width: 100%;
height: 100%;
position: fixed;
z-index: 999;
background-color: rgba(0, 0, 0, 0.6);
top: 0;
}
.conent-model {
position: fixed;
left: 50%;
top: 50%;
width: 622rpx;
margin-left: -311rpx;
margin-top: -200rpx;
z-index: 999;
background: #fff;
border-radius: 8rpx;
padding-top: 32rpx;
}
.title {
display: block;
text-align: center;
font-size: 36rpx;
color: #3c3c3c;
}
.content {
display: block;
text-align: center;
font-size: 30rpx;
padding: 32rpx;
color: #999;
}
.quickBtn {
width: 100%;
height: 96rpx;
border-top: 2rpx solid #EEE;
line-height: 96rpx;
}
.cancel-btn {
width: 50%;
display: inline-block;
color: #3c3c3c;
font-size: 32rpx;
text-align: center;
height: 96rpx;
line-height: 96rpx;
border-right: 1rpx solid #EEE;
}
.confirm-btn {
width: 50%;
display: inline-block;
color: #00cc88;
font-size: 32rpx;
height: 96rpx;
line-height: 96rpx;
text-align: center;
border-left: 1rpx solid #EEE;
}2、painter lib
代码语言：javascript复制/**
* LRU 文件存储，使用该 downloader 可以让下载的文件存储在本地，下次进入小程序后可以直接使用
*/
const util = require('./util');
const SAVED_FILES_KEY = 'savedFiles';
const KEY_TOTAL_SIZE = 'totalSize';
const KEY_PATH = 'path';
const KEY_TIME = 'time';
const KEY_SIZE = 'size';
// 可存储总共为 6M，目前小程序可允许的最大本地存储为 10M
let MAX_SPACE_IN_B = 6 * 1024 * 1024;
let savedFiles = {};
export default class Dowloader {
constructor() {
// app 如果设置了最大存储空间，则使用 app 中的
if (getApp().PAINTER_MAX_LRU_SPACE) {
MAX_SPACE_IN_B = getApp().PAINTER_MAX_LRU_SPACE;
}
wx.getStorage({
key: SAVED_FILES_KEY,
success: function (res) {
if (res.data) {
savedFiles = res.data;
}
},
});
}
/**
* 下载文件，会用 lru 方式来缓存文件到本地
* @param {String} url 文件的 url
*/
download(url) {
return new Promise((resolve, reject) => {
if (!(url && util.isValidUrl(url))) {
resolve(url);
return;
}
const file = getFile(url);
if (file) {
// 检查文件是否正常，不正常需要重新下载
wx.getSavedFileInfo({
filePath: file[KEY_PATH],
success: (res) => {
resolve(file[KEY_PATH]);
},
fail: (error) => {
console.error(`the file is broken, redownload it, ${JSON.stringify(error)}`);
downloadFile(url).then((path) => {
resolve(path);
}, () => {
reject();
});
},
});
} else {
downloadFile(url).then((path) => {
resolve(path);
}, () => {
reject();
});
}
});
}
}
function downloadFile(url) {
return new Promise((resolve, reject) => {
wx.downloadFile({
url: url,
success: function (res) {
if (res.statusCode !== 200) {
console.error(`downloadFile ${url} failed res.statusCode is not 200`);
reject();
return;
}
const { tempFilePath } = res;
wx.getFileInfo({
filePath: tempFilePath,
success: (tmpRes) => {
const newFileSize = tmpRes.size;
doLru(newFileSize).then(() => {
saveFile(url, newFileSize, tempFilePath).then((filePath) => {
resolve(filePath);
});
}, () => {
resolve(tempFilePath);
});
},
fail: (error) => {
// 文件大小信息获取失败，则此文件也不要进行存储
console.error(`getFileInfo ${res.tempFilePath} failed, ${JSON.stringify(error)}`);
resolve(res.tempFilePath);
},
});
},
fail: function (error) {
console.error(`downloadFile failed, ${JSON.stringify(error)} `);
reject();
},
});
});
}
function saveFile(key, newFileSize, tempFilePath) {
return new Promise((resolve, reject) => {
wx.saveFile({
tempFilePath: tempFilePath,
success: (fileRes) => {
const totalSize = savedFiles[KEY_TOTAL_SIZE] ? savedFiles[KEY_TOTAL_SIZE] : 0;
savedFiles[key] = {};
savedFiles[key][KEY_PATH] = fileRes.savedFilePath;
savedFiles[key][KEY_TIME] = new Date().getTime();
savedFiles[key][KEY_SIZE] = newFileSize;
savedFiles['totalSize'] = newFileSize totalSize;
wx.setStorage({
key: SAVED_FILES_KEY,
data: savedFiles,
});
resolve(fileRes.savedFilePath);
},
fail: (error) => {
console.error(`saveFile ${key} failed, then we delete all files, ${JSON.stringify(error)}`);
// 由于 saveFile 成功后，res.tempFilePath 处的文件会被移除，所以在存储未成功时，我们还是继续使用临时文件
resolve(tempFilePath);
// 如果出现错误，就直接情况本地的所有文件，因为你不知道是不是因为哪次lru的某个文件未删除成功
reset();
},
});
});
}
/**
* 清空所有下载相关内容
*/
function reset() {
wx.removeStorage({
key: SAVED_FILES_KEY,
success: () => {
wx.getSavedFileList({
success: (listRes) => {
removeFiles(listRes.fileList);
},
fail: (getError) => {
console.error(`getSavedFileList failed, ${JSON.stringify(getError)}`);
},
});
},
});
}
function doLru(size) {
return new Promise((resolve, reject) => {
let totalSize = savedFiles[KEY_TOTAL_SIZE] ? savedFiles[KEY_TOTAL_SIZE] : 0;
if (size totalSize <= MAX_SPACE_IN_B) {
resolve();
return;
}
// 如果加上新文件后大小超过最大限制，则进行 lru
const pathsShouldDelete = [];
// 按照最后一次的访问时间，从小到大排序
const allFiles = JSON.parse(JSON.stringify(savedFiles));
delete allFiles[KEY_TOTAL_SIZE];
const sortedKeys = Object.keys(allFiles).sort((a, b) => {
return allFiles[a][KEY_TIME] - allFiles[b][KEY_TIME];
});
for (const sortedKey of sortedKeys) {
totalSize -= savedFiles[sortedKey].size;
pathsShouldDelete.push(savedFiles[sortedKey][KEY_PATH]);
delete savedFiles[sortedKey];
if (totalSize size < MAX_SPACE_IN_B) {
break;
}
}
savedFiles['totalSize'] = totalSize;
wx.setStorage({
key: SAVED_FILES_KEY,
data: savedFiles,
success: () => {
// 保证 storage 中不会存在不存在的文件数据
if (pathsShouldDelete.length > 0) {
removeFiles(pathsShouldDelete);
}
resolve();
},
fail: (error) => {
console.error(`doLru setStorage failed, ${JSON.stringify(error)}`);
reject();
},
});
});
}
function removeFiles(pathsShouldDelete) {
for (const pathDel of pathsShouldDelete) {
let delPath = pathDel;
if (typeof pathDel === 'object') {
delPath = pathDel.filePath;
}
wx.removeSavedFile({
filePath: delPath,
fail: (error) => {
console.error(`removeSavedFile ${pathDel} failed, ${JSON.stringify(error)}`);
},
});
}
}
function getFile(key) {
if (!savedFiles[key]) {
return;
}
savedFiles[key]['time'] = new Date().getTime();
wx.setStorage({
key: SAVED_FILES_KEY,
data: savedFiles,
});
return savedFiles[key];
}const QR = require('./qrcode.js');
export default class Painter {
constructor(ctx, data) {
this.ctx = ctx;
this.data = data;
}
paint(callback) {
this.style = {
width: this.data.width.toPx(),
height: this.data.height.toPx(),
};
this._background();
for (const view of this.data.views) {
this._drawAbsolute(view);
}
this.ctx.draw(false, () => {
callback();
});
}
_background() {
this.ctx.save();
const {
width,
height,
} = this.style;
const bg = this.data.background;
this.ctx.translate(width / 2, height / 2);
this._doClip(this.data.borderRadius, width, height);
if (!bg) {
// 如果未设置背景，则默认使用白色
this.ctx.fillStyle = '#fff';
this.ctx.fillRect(-(width / 2), -(height / 2), width, height);
} else if (bg.startsWith('#') || bg.startsWith('rgba') || bg.toLowerCase() === 'transparent') {
// 背景填充颜色
this.ctx.fillStyle = bg;
this.ctx.fillRect(-(width / 2), -(height / 2), width, height);
} else {
// 背景填充图片
this.ctx.drawImage(bg, -(width / 2), -(height / 2), width, height);
}
this.ctx.restore();
}
_drawAbsolute(view) {
// 证明 css 为数组形式，需要合并
if (view.css && view.css.length) {
/* eslint-disable no-param-reassign */
view.css = Object.assign(...view.css);
}
switch (view.type) {
case 'image':
this._drawAbsImage(view);
break;
case 'text':
this._fillAbsText(view);
break;
case 'rect':
this._drawAbsRect(view);
break;
case 'qrcode':
this._drawQRCode(view);
break;
default:
break;
}
}
/**
* 根据 borderRadius 进行裁减
*/
_doClip(borderRadius, width, height) {
if (borderRadius && width && height) {
const r = Math.min(borderRadius.toPx(), width / 2, height / 2);
// 防止在某些机型上周边有黑框现象，此处如果直接设置 setFillStyle 为透明，在 Android 机型上会导致被裁减的图片也变为透明， iOS 和 IDE 上不会
// setGlobalAlpha 在 1.9.90 起支持，低版本下无效，但把 setFillStyle 设为了 white，相对默认的 black 要好点
this.ctx.globalAlpha = 0;
this.ctx.fillStyle = 'white';
this.ctx.beginPath();
this.ctx.arc(-width / 2 r, -height / 2 r, r, 1 * Math.PI, 1.5 * Math.PI);
this.ctx.lineTo(width / 2 - r, -height / 2);
this.ctx.arc(width / 2 - r, -height / 2 r, r, 1.5 * Math.PI, 2 * Math.PI);
this.ctx.lineTo(width / 2, height / 2 - r);
this.ctx.arc(width / 2 - r, height / 2 - r, r, 0, 0.5 * Math.PI);
this.ctx.lineTo(-width / 2 r, height / 2);
this.ctx.arc(-width / 2 r, height / 2 - r, r, 0.5 * Math.PI, 1 * Math.PI);
this.ctx.closePath();
this.ctx.fill();
// 在 ios 的 6.6.6 版本上 clip 有 bug，禁掉此类型上的 clip，也就意味着，在此版本微信的 ios 设备下无法使用 border 属性
if (!(getApp().systemInfo &&
getApp().systemInfo.version <= '6.6.6' &&
getApp().systemInfo.platform === 'ios')) {
this.ctx.clip();
}
this.ctx.globalAlpha = 1;
}
}
/**
* 画边框
*/
_doBorder(view, width, height) {
if (!view.css) {
return;
}
const {
borderRadius,
borderWidth,
borderColor,
} = view.css;
if (!borderWidth) {
return;
}
this.ctx.save();
this._preProcess(view, true);
let r;
if (borderRadius) {
r = Math.min(borderRadius.toPx(), width / 2, height / 2);
} else {
r = 0;
}
const lineWidth = borderWidth.toPx();
this.ctx.lineWidth = lineWidth;
this.ctx.strokeStyle = borderColor || 'black';
this.ctx.beginPath();
this.ctx.arc(-width / 2 r, -height / 2 r, r lineWidth / 2, 1 * Math.PI, 1.5 * Math.PI);
this.ctx.lineTo(width / 2 - r, -height / 2 - lineWidth / 2);
this.ctx.arc(width / 2 - r, -height / 2 r, r lineWidth / 2, 1.5 * Math.PI, 2 * Math.PI);
this.ctx.lineTo(width / 2 lineWidth / 2, height / 2 - r);
this.ctx.arc(width / 2 - r, height / 2 - r, r lineWidth / 2, 0, 0.5 * Math.PI);
this.ctx.lineTo(-width / 2 r, height / 2 lineWidth / 2);
this.ctx.arc(-width / 2 r, height / 2 - r, r lineWidth / 2, 0.5 * Math.PI, 1 * Math.PI);
this.ctx.closePath();
this.ctx.stroke();
this.ctx.restore();
}
_preProcess(view, notClip) {
let width;
let height;
let extra;
switch (view.type) {
case 'text': {
const fontWeight = view.css.fontWeight === 'bold' ? 'bold' : 'normal';
view.css.fontSize = view.css.fontSize ? view.css.fontSize : '20rpx';
this.ctx.font = `normal ${fontWeight} ${view.css.fontSize.toPx()}px sans-serif`;
// this.ctx.setFontSize(view.css.fontSize.toPx());
const textLength = this.ctx.measureText(view.text).width;
width = view.css.width ? view.css.width.toPx() : textLength;
// 计算行数
const calLines = Math.ceil(textLength / width);
const lines = view.css.maxLines < calLines ? view.css.maxLines : calLines;
const lineHeight = view.css.lineHeight ? view.css.lineHeight.toPx() : view.css.fontSize.toPx();
height = lineHeight * lines;
extra = { lines: lines, lineHeight: lineHeight };
break;
}
case 'image': {
// image 如果未设置长宽，则使用图片本身的长宽
const ratio = getApp().systemInfo.pixelRatio ? getApp().systemInfo.pixelRatio : 2;
width = view.css && view.css.width ? view.css.width.toPx() : Math.round(view.sWidth / ratio);
height = view.css && view.css.height ? view.css.height.toPx() : Math.round(view.sHeight / ratio);
break;
}
default: {
if (!(view.css.width && view.css.height)) {
console.error('You should set width and height');
return;
}
width = view.css.width.toPx();
height = view.css.height.toPx();
}
}
const x = view.css && view.css.right ? this.style.width - view.css.right.toPx(true) : (view.css && view.css.left ? view.css.left.toPx(true) : 0);
const y = view.css && view.css.bottom ? this.style.height - height - view.css.bottom.toPx(true) : (view.css && view.css.top ? view.css.top.toPx(true) : 0);
const angle = view.css && view.css.rotate ? this._getAngle(view.css.rotate) : 0;
// 当设置了 right 时，默认 align 用 right，反之用 left
const align = view.css && view.css.align ? view.css.align : (view.css && view.css.right ? 'right' : 'left');
switch (align) {
case 'center':
this.ctx.translate(x, y height / 2);
break;
case 'right':
this.ctx.translate(x - width / 2, y height / 2);
break;
default:
this.ctx.translate(x width / 2, y height / 2);
break;
}
this.ctx.rotate(angle);
if (!notClip && view.css && view.css.borderRadius) {
this._doClip(view.css.borderRadius, width, height);
}
return {
width: width,
height: height,
x: x,
y: y,
extra: extra,
};
}
_drawQRCode(view) {
this.ctx.save();
const {
width,
height,
} = this._preProcess(view);
QR.api.draw(view.content, this.ctx, -width / 2, -height / 2, width, height, view.css.background, view.css.color);
this.ctx.restore();
this._doBorder(view, width, height);
}
_drawAbsImage(view) {
if (!view.url) {
return;
}
this.ctx.save();
const {
width,
height,
} = this._preProcess(view);
// 获得缩放到图片大小级别的裁减框
let rWidth;
let rHeight;
let startX = 0;
let startY = 0;
if (width > height) {
rHeight = Math.round((view.sWidth / width) * height);
rWidth = view.sWidth;
} else {
rWidth = Math.round((view.sHeight / height) * width);
rHeight = view.sHeight;
}
if (view.sWidth > rWidth) {
startX = Math.round((view.sWidth - rWidth) / 2);
}
if (view.sHeight > rHeight) {
startY = Math.round((view.sHeight - rHeight) / 2);
}
if (view.css && view.css.mode === 'scaleToFill') {
this.ctx.drawImage(view.url, -(width / 2), -(height / 2), width, height);
} else {
this.ctx.drawImage(view.url, startX, startY, rWidth, rHeight, -(width / 2), -(height / 2), width, height);
}
this.ctx.restore();
this._doBorder(view, width, height);
}
_fillAbsText(view) {
if (!view.text) {
return;
}
this.ctx.save();
const {
width,
height,
extra,
} = this._preProcess(view);
this.ctx.fillStyle = view.css.color || 'black';
const { lines, lineHeight } = extra;
const preLineLength = Math.round(view.text.length / lines);
let start = 0;
let alreadyCount = 0;
for (let i = 0; i < lines; i) {
alreadyCount = preLineLength;
let text = view.text.substr(start, alreadyCount);
let measuredWith = this.ctx.measureText(text).width;
// 如果测量大小小于width一个字符的大小，则进行补齐，如果测量大小超出 width，则进行减除
// 如果已经到文本末尾，也不要进行该循环
while ((start alreadyCount <= view.text.length) && (width - measuredWith > view.css.fontSize.toPx() || measuredWith > width)) {
if (measuredWith < width) {
text = view.text.substr(start, alreadyCount);
} else {
if (text.length <= 1) {
// 如果只有一个字符时，直接跳出循环
break;
}
text = view.text.substr(start, --alreadyCount);
}
measuredWith = this.ctx.measureText(text).width;
}
start = text.length;
// 如果是最后一行了，发现还有未绘制完的内容，则加...
if (i === lines - 1 && start < view.text.length) {
while (this.ctx.measureText(`${text}...`).width > width) {
if (text.length <= 1) {
// 如果只有一个字符时，直接跳出循环
break;
}
text = text.substring(0, text.length - 1);
}
text = '...';
measuredWith = this.ctx.measureText(text).width;
}
this.ctx.setTextAlign(view.css.align ? view.css.align : 'left');
let x;
switch (view.css.align) {
case 'center':
x = 0;
break;
case 'right':
x = (width / 2);
break;
default:
x = -(width / 2);
break;
}
const y = -(height / 2) (i === 0 ? view.css.fontSize.toPx() : (view.css.fontSize.toPx() i * lineHeight));
if (view.css.textStyle === 'stroke') {
this.ctx.strokeText(text, x, y, measuredWith);
} else {
this.ctx.fillText(text, x, y, measuredWith);
}
const fontSize = view.css.fontSize.toPx();
if (view.css.textDecoration) {
this.ctx.beginPath();
if (/bunderlineb/.test(view.css.textDecoration)) {
this.ctx.moveTo(x, y);
this.ctx.lineTo(x measuredWith, y);
}
if (/boverlineb/.test(view.css.textDecoration)) {
this.ctx.moveTo(x, y - fontSize);
this.ctx.lineTo(x measuredWith, y - fontSize);
}
if (/bline-throughb/.test(view.css.textDecoration)) {
this.ctx.moveTo(x, y - fontSize / 3);
this.ctx.lineTo(x measuredWith, y - fontSize / 3);
}
this.ctx.closePath();
this.ctx.strokeStyle = view.css.color;
this.ctx.stroke();
}
}
this.ctx.restore();
this._doBorder(view, width, height);
}
_drawAbsRect(view) {
this.ctx.save();
const {
width,
height,
} = this._preProcess(view);
this.ctx.fillStyle = view.css.color;
this.ctx.fillRect(-(width / 2), -(height / 2), width, height);
this.ctx.restore();
this._doBorder(view, width, height);
}
_getAngle(angle) {
return Number(angle) * Math.PI / 180;
}
}/* eslint-disable */
!(function () {
// alignment pattern
var adelta = [
0, 11, 15, 19, 23, 27, 31,
16, 18, 20, 22, 24, 26, 28, 20, 22, 24, 24, 26, 28, 28, 22, 24, 24,
26, 26, 28, 28, 24, 24, 26, 26, 26, 28, 28, 24, 26, 26, 26, 28, 28
];
// version block
var vpat = [
0xc94, 0x5bc, 0xa99, 0x4d3, 0xbf6, 0x762, 0x847, 0x60d,
0x928, 0xb78, 0x45d, 0xa17, 0x532, 0x9a6, 0x683, 0x8c9,
0x7ec, 0xec4, 0x1e1, 0xfab, 0x08e, 0xc1a, 0x33f, 0xd75,
0x250, 0x9d5, 0x6f0, 0x8ba, 0x79f, 0xb0b, 0x42e, 0xa64,
0x541, 0xc69
];
// final format bits with mask: level << 3 | mask
var fmtword = [
0x77c4, 0x72f3, 0x7daa, 0x789d, 0x662f, 0x6318, 0x6c41, 0x6976, //L
0x5412, 0x5125, 0x5e7c, 0x5b4b, 0x45f9, 0x40ce, 0x4f97, 0x4aa0, //M
0x355f, 0x3068, 0x3f31, 0x3a06, 0x24b4, 0x2183, 0x2eda, 0x2bed, //Q
0x1689, 0x13be, 0x1ce7, 0x19d0, 0x0762, 0x0255, 0x0d0c, 0x083b //H
];
// 4 per version: number of blocks 1,2; data width; ecc width
var eccblocks = [
1, 0, 19, 7, 1, 0, 16, 10, 1, 0, 13, 13, 1, 0, 9, 17,
1, 0, 34, 10, 1, 0, 28, 16, 1, 0, 22, 22, 1, 0, 16, 28,
1, 0, 55, 15, 1, 0, 44, 26, 2, 0, 17, 18, 2, 0, 13, 22,
1, 0, 80, 20, 2, 0, 32, 18, 2, 0, 24, 26, 4, 0, 9, 16,
1, 0, 108, 26, 2, 0, 43, 24, 2, 2, 15, 18, 2, 2, 11, 22,
2, 0, 68, 18, 4, 0, 27, 16, 4, 0, 19, 24, 4, 0, 15, 28,
2, 0, 78, 20, 4, 0, 31, 18, 2, 4, 14, 18, 4, 1, 13, 26,
2, 0, 97, 24, 2, 2, 38, 22, 4, 2, 18, 22, 4, 2, 14, 26,
2, 0, 116, 30, 3, 2, 36, 22, 4, 4, 16, 20, 4, 4, 12, 24,
2, 2, 68, 18, 4, 1, 43, 26, 6, 2, 19, 24, 6, 2, 15, 28,
4, 0, 81, 20, 1, 4, 50, 30, 4, 4, 22, 28, 3, 8, 12, 24,
2, 2, 92, 24, 6, 2, 36, 22, 4, 6, 20, 26, 7, 4, 14, 28,
4, 0, 107, 26, 8, 1, 37, 22, 8, 4, 20, 24, 12, 4, 11, 22,
3, 1, 115, 30, 4, 5, 40, 24, 11, 5, 16, 20, 11, 5, 12, 24,
5, 1, 87, 22, 5, 5, 41, 24, 5, 7, 24, 30, 11, 7, 12, 24,
5, 1, 98, 24, 7, 3, 45, 28, 15, 2, 19, 24, 3, 13, 15, 30,
1, 5, 107, 28, 10, 1, 46, 28, 1, 15, 22, 28, 2, 17, 14, 28,
5, 1, 120, 30, 9, 4, 43, 26, 17, 1, 22, 28, 2, 19, 14, 28,
3, 4, 113, 28, 3, 11, 44, 26, 17, 4, 21, 26, 9, 16, 13, 26,
3, 5, 107, 28, 3, 13, 41, 26, 15, 5, 24, 30, 15, 10, 15, 28,
4, 4, 116, 28, 17, 0, 42, 26, 17, 6, 22, 28, 19, 6, 16, 30,
2, 7, 111, 28, 17, 0, 46, 28, 7, 16, 24, 30, 34, 0, 13, 24,
4, 5, 121, 30, 4, 14, 47, 28, 11, 14, 24, 30, 16, 14, 15, 30,
6, 4, 117, 30, 6, 14, 45, 28, 11, 16, 24, 30, 30, 2, 16, 30,
8, 4, 106, 26, 8, 13, 47, 28, 7, 22, 24, 30, 22, 13, 15, 30,
10, 2, 114, 28, 19, 4, 46, 28, 28, 6, 22, 28, 33, 4, 16, 30,
8, 4, 122, 30, 22, 3, 45, 28, 8, 26, 23, 30, 12, 28, 15, 30,
3, 10, 117, 30, 3, 23, 45, 28, 4, 31, 24, 30, 11, 31, 15, 30,
7, 7, 116, 30, 21, 7, 45, 28, 1, 37, 23, 30, 19, 26, 15, 30,
5, 10, 115, 30, 19, 10, 47, 28, 15, 25, 24, 30, 23, 25, 15, 30,
13, 3, 115, 30, 2, 29, 46, 28, 42, 1, 24, 30, 23, 28, 15, 30,
17, 0, 115, 30, 10, 23, 46, 28, 10, 35, 24, 30, 19, 35, 15, 30,
17, 1, 115, 30, 14, 21, 46, 28, 29, 19, 24, 30, 11, 46, 15, 30,
13, 6, 115, 30, 14, 23, 46, 28, 44, 7, 24, 30, 59, 1, 16, 30,
12, 7, 121, 30, 12, 26, 47, 28, 39, 14, 24, 30, 22, 41, 15, 30,
6, 14, 121, 30, 6, 34, 47, 28, 46, 10, 24, 30, 2, 64, 15, 30,
17, 4, 122, 30, 29, 14, 46, 28, 49, 10, 24, 30, 24, 46, 15, 30,
4, 18, 122, 30, 13, 32, 46, 28, 48, 14, 24, 30, 42, 32, 15, 30,
20, 4, 117, 30, 40, 7, 47, 28, 43, 22, 24, 30, 10, 67, 15, 30,
19, 6, 118, 30, 18, 31, 47, 28, 34, 34, 24, 30, 20, 61, 15, 30
];
// Galois field log table
var glog = [
0xff, 0x00, 0x01, 0x19, 0x02, 0x32, 0x1a, 0xc6, 0x03, 0xdf, 0x33, 0xee, 0x1b, 0x68, 0xc7, 0x4b,
0x04, 0x64, 0xe0, 0x0e, 0x34, 0x8d, 0xef, 0x81, 0x1c, 0xc1, 0x69, 0xf8, 0xc8, 0x08, 0x4c, 0x71,
0x05, 0x8a, 0x65, 0x2f, 0xe1, 0x24, 0x0f, 0x21, 0x35, 0x93, 0x8e, 0xda, 0xf0, 0x12, 0x82, 0x45,
0x1d, 0xb5, 0xc2, 0x7d, 0x6a, 0x27, 0xf9, 0xb9, 0xc9, 0x9a, 0x09, 0x78, 0x4d, 0xe4, 0x72, 0xa6,
0x06, 0xbf, 0x8b, 0x62, 0x66, 0xdd, 0x30, 0xfd, 0xe2, 0x98, 0x25, 0xb3, 0x10, 0x91, 0x22, 0x88,
0x36, 0xd0, 0x94, 0xce, 0x8f, 0x96, 0xdb, 0xbd, 0xf1, 0xd2, 0x13, 0x5c, 0x83, 0x38, 0x46, 0x40,
0x1e, 0x42, 0xb6, 0xa3, 0xc3, 0x48, 0x7e, 0x6e, 0x6b, 0x3a, 0x28, 0x54, 0xfa, 0x85, 0xba, 0x3d,
0xca, 0x5e, 0x9b, 0x9f, 0x0a, 0x15, 0x79, 0x2b, 0x4e, 0xd4, 0xe5, 0xac, 0x73, 0xf3, 0xa7, 0x57,
0x07, 0x70, 0xc0, 0xf7, 0x8c, 0x80, 0x63, 0x0d, 0x67, 0x4a, 0xde, 0xed, 0x31, 0xc5, 0xfe, 0x18,
0xe3, 0xa5, 0x99, 0x77, 0x26, 0xb8, 0xb4, 0x7c, 0x11, 0x44, 0x92, 0xd9, 0x23, 0x20, 0x89, 0x2e,
0x37, 0x3f, 0xd1, 0x5b, 0x95, 0xbc, 0xcf, 0xcd, 0x90, 0x87, 0x97, 0xb2, 0xdc, 0xfc, 0xbe, 0x61,
0xf2, 0x56, 0xd3, 0xab, 0x14, 0x2a, 0x5d, 0x9e, 0x84, 0x3c, 0x39, 0x53, 0x47, 0x6d, 0x41, 0xa2,
0x1f, 0x2d, 0x43, 0xd8, 0xb7, 0x7b, 0xa4, 0x76, 0xc4, 0x17, 0x49, 0xec, 0x7f, 0x0c, 0x6f, 0xf6,
0x6c, 0xa1, 0x3b, 0x52, 0x29, 0x9d, 0x55, 0xaa, 0xfb, 0x60, 0x86, 0xb1, 0xbb, 0xcc, 0x3e, 0x5a,
0xcb, 0x59, 0x5f, 0xb0, 0x9c, 0xa9, 0xa0, 0x51, 0x0b, 0xf5, 0x16, 0xeb, 0x7a, 0x75, 0x2c, 0xd7,
0x4f, 0xae, 0xd5, 0xe9, 0xe6, 0xe7, 0xad, 0xe8, 0x74, 0xd6, 0xf4, 0xea, 0xa8, 0x50, 0x58, 0xaf
];
// Galios field exponent table
var gexp = [
0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1d, 0x3a, 0x74, 0xe8, 0xcd, 0x87, 0x13, 0x26,
0x4c, 0x98, 0x2d, 0x5a, 0xb4, 0x75, 0xea, 0xc9, 0x8f, 0x03, 0x06, 0x0c, 0x18, 0x30, 0x60, 0xc0,
0x9d, 0x27, 0x4e, 0x9c, 0x25, 0x4a, 0x94, 0x35, 0x6a, 0xd4, 0xb5, 0x77, 0xee, 0xc1, 0x9f, 0x23,
0x46, 0x8c, 0x05, 0x0a, 0x14, 0x28, 0x50, 0xa0, 0x5d, 0xba, 0x69, 0xd2, 0xb9, 0x6f, 0xde, 0xa1,
0x5f, 0xbe, 0x61, 0xc2, 0x99, 0x2f, 0x5e, 0xbc, 0x65, 0xca, 0x89, 0x0f, 0x1e, 0x3c, 0x78, 0xf0,
0xfd, 0xe7, 0xd3, 0xbb, 0x6b, 0xd6, 0xb1, 0x7f, 0xfe, 0xe1, 0xdf, 0xa3, 0x5b, 0xb6, 0x71, 0xe2,
0xd9, 0xaf, 0x43, 0x86, 0x11, 0x22, 0x44, 0x88, 0x0d, 0x1a, 0x34, 0x68, 0xd0, 0xbd, 0x67, 0xce,
0x81, 0x1f, 0x3e, 0x7c, 0xf8, 0xed, 0xc7, 0x93, 0x3b, 0x76, 0xec, 0xc5, 0x97, 0x33, 0x66, 0xcc,
0x85, 0x17, 0x2e, 0x5c, 0xb8, 0x6d, 0xda, 0xa9, 0x4f, 0x9e, 0x21, 0x42, 0x84, 0x15, 0x2a, 0x54,
0xa8, 0x4d, 0x9a, 0x29, 0x52, 0xa4, 0x55, 0xaa, 0x49, 0x92, 0x39, 0x72, 0xe4, 0xd5, 0xb7, 0x73,
0xe6, 0xd1, 0xbf, 0x63, 0xc6, 0x91, 0x3f, 0x7e, 0xfc, 0xe5, 0xd7, 0xb3, 0x7b, 0xf6, 0xf1, 0xff,
0xe3, 0xdb, 0xab, 0x4b, 0x96, 0x31, 0x62, 0xc4, 0x95, 0x37, 0x6e, 0xdc, 0xa5, 0x57, 0xae, 0x41,
0x82, 0x19, 0x32, 0x64, 0xc8, 0x8d, 0x07, 0x0e, 0x1c, 0x38, 0x70, 0xe0, 0xdd, 0xa7, 0x53, 0xa6,
0x51, 0xa2, 0x59, 0xb2, 0x79, 0xf2, 0xf9, 0xef, 0xc3, 0x9b, 0x2b, 0x56, 0xac, 0x45, 0x8a, 0x09,
0x12, 0x24, 0x48, 0x90, 0x3d, 0x7a, 0xf4, 0xf5, 0xf7, 0xf3, 0xfb, 0xeb, 0xcb, 0x8b, 0x0b, 0x16,
0x2c, 0x58, 0xb0, 0x7d, 0xfa, 0xe9, 0xcf, 0x83, 0x1b, 0x36, 0x6c, 0xd8, 0xad, 0x47, 0x8e, 0x00
];
// Working buffers:
// data input and ecc append, image working buffer, fixed part of image, run lengths for badness
var strinbuf = [], eccbuf = [], qrframe = [], framask = [], rlens = [];
// Control values - width is based on version, last 4 are from table.
var version, width, neccblk1, neccblk2, datablkw, eccblkwid;
var ecclevel = 2;
// set bit to indicate cell in qrframe is immutable. symmetric around diagonal
function setmask(x, y) {
var bt;
if (x > y) {
bt = x;
x = y;
y = bt;
}
// y*y = 1 3 5...
bt = y;
bt *= y;
bt = y;
bt >>= 1;
bt = x;
framask[bt] = 1;
}
// enter alignment pattern - black to qrframe, white to mask (later black frame merged to mask)
function putalign(x, y) {
var j;
qrframe[x width * y] = 1;
for (j = -2; j < 2; j ) {
qrframe[(x j) width * (y - 2)] = 1;
qrframe[(x - 2) width * (y j 1)] = 1;
qrframe[(x 2) width * (y j)] = 1;
qrframe[(x j 1) width * (y 2)] = 1;
}
for (j = 0; j < 2; j ) {
setmask(x - 1, y j);
setmask(x 1, y - j);
setmask(x - j, y - 1);
setmask(x j, y 1);
}
}
//========================================================================
// Reed Solomon error correction
// exponentiation mod N
function modnn(x) {
while (x >= 255) {
x -= 255;
x = (x >> 8) (x & 255);
}
return x;
}
var genpoly = [];
// Calculate and append ECC data to data block. Block is in strinbuf, indexes to buffers given.
function appendrs(data, dlen, ecbuf, eclen) {
var i, j, fb;
for (i = 0; i < eclen; i )
strinbuf[ecbuf i] = 0;
for (i = 0; i < dlen; i ) {
fb = glog[strinbuf[data i] ^ strinbuf[ecbuf]];
if (fb != 255) /* fb term is non-zero */
for (j = 1; j < eclen; j )
strinbuf[ecbuf j - 1] = strinbuf[ecbuf j] ^ gexp[modnn(fb genpoly[eclen - j])];
else
for (j = ecbuf; j < ecbuf eclen; j )
strinbuf[j] = strinbuf[j 1];
strinbuf[ecbuf eclen - 1] = fb == 255 ? 0 : gexp[modnn(fb genpoly[0])];
}
}
//========================================================================
// Frame data insert following the path rules
// check mask - since symmetrical use half.
function ismasked(x, y) {
var bt;
if (x > y) {
bt = x;
x = y;
y = bt;
}
bt = y;
bt = y * y;
bt >>= 1;
bt = x;
return framask[bt];
}
//========================================================================
// Apply the selected mask out of the 8.
function applymask(m) {
var x, y, r3x, r3y;
switch (m) {
case 0:
for (y = 0; y < width; y )
for (x = 0; x < width; x )
if (!((x y) & 1) && !ismasked(x, y))
qrframe[x y * width] ^= 1;
break;
case 1:
for (y = 0; y < width; y )
for (x = 0; x < width; x )
if (!(y & 1) && !ismasked(x, y))
qrframe[x y * width] ^= 1;
break;
case 2:
for (y = 0; y < width; y )
for (r3x = 0, x = 0; x < width; x , r3x ) {
if (r3x == 3)
r3x = 0;
if (!r3x && !ismasked(x, y))
qrframe[x y * width] ^= 1;
}
break;
case 3:
for (r3y = 0, y = 0; y < width; y , r3y ) {
if (r3y == 3)
r3y = 0;
for (r3x = r3y, x = 0; x < width; x , r3x ) {
if (r3x == 3)
r3x = 0;
if (!r3x && !ismasked(x, y))
qrframe[x y * width] ^= 1;
}
}
break;
case 4:
for (y = 0; y < width; y )
for (r3x = 0, r3y = ((y >> 1) & 1), x = 0; x < width; x , r3x ) {
if (r3x == 3) {
r3x = 0;
r3y = !r3y;
}
if (!r3y && !ismasked(x, y))
qrframe[x y * width] ^= 1;
}
break;
case 5:
for (r3y = 0, y = 0; y < width; y , r3y ) {
if (r3y == 3)
r3y = 0;
for (r3x = 0, x = 0; x < width; x , r3x ) {
if (r3x == 3)
r3x = 0;
if (!((x & y & 1) !(!r3x | !r3y)) && !ismasked(x, y))
qrframe[x y * width] ^= 1;
}
}
break;
case 6:
for (r3y = 0, y = 0; y < width; y , r3y ) {
if (r3y == 3)
r3y = 0;
for (r3x = 0, x = 0; x < width; x , r3x ) {
if (r3x == 3)
r3x = 0;
if (!(((x & y & 1) (r3x && (r3x == r3y))) & 1) && !ismasked(x, y))
qrframe[x y * width] ^= 1;
}
}
break;
case 7:
for (r3y = 0, y = 0; y < width; y , r3y ) {
if (r3y == 3)
r3y = 0;
for (r3x = 0, x = 0; x < width; x , r3x ) {
if (r3x == 3)
r3x = 0;
if (!(((r3x && (r3x == r3y)) ((x y) & 1)) & 1) && !ismasked(x, y))
qrframe[x y * width] ^= 1;
}
}
break;
}
return;
}
// Badness coefficients.
var N1 = 3, N2 = 3, N3 = 40, N4 = 10;
// Using the table of the length of each run, calculate the amount of bad image
// - long runs or those that look like finders; called twice, once each for X and Y
function badruns(length) {
var i;
var runsbad = 0;
for (i = 0; i <= length; i )
if (rlens[i] >= 5)
runsbad = N1 rlens[i] - 5;
// BwBBBwB as in finder
for (i = 3; i < length - 1; i = 2)
if (rlens[i - 2] == rlens[i 2]
&& rlens[i 2] == rlens[i - 1]
&& rlens[i - 1] == rlens[i 1]
&& rlens[i - 1] * 3 == rlens[i]
// white around the black pattern? Not part of spec
&& (rlens[i - 3] == 0 // beginning
|| i 3 > length // end
|| rlens[i - 3] * 3 >= rlens[i] * 4 || rlens[i 3] * 3 >= rlens[i] * 4)
)
runsbad = N3;
return runsbad;
}
// Calculate how bad the masked image is - blocks, imbalance, runs, or finders.
function badcheck() {
var x, y, h, b, b1;
var thisbad = 0;
var bw = 0;
// blocks of same color.
for (y = 0; y < width - 1; y )
for (x = 0; x < width - 1; x )
if ((qrframe[x width * y] && qrframe[(x 1) width * y]
&& qrframe[x width * (y 1)] && qrframe[(x 1) width * (y 1)]) // all black
|| !(qrframe[x width * y] || qrframe[(x 1) width * y]
|| qrframe[x width * (y 1)] || qrframe[(x 1) width * (y 1)])) // all white
thisbad = N2;
// X runs
for (y = 0; y < width; y ) {
rlens[0] = 0;
for (h = b = x = 0; x < width; x ) {
if ((b1 = qrframe[x width * y]) == b)
rlens[h] ;
else
rlens[ h] = 1;
b = b1;
bw = b ? 1 : -1;
}
thisbad = badruns(h);
}
// black/white imbalance
if (bw < 0)
bw = -bw;
var big = bw;
var count = 0;
big = big << 2;
big <<= 1;
while (big > width * width)
big -= width * width, count ;
thisbad = count * N4;
// Y runs
for (x = 0; x < width; x ) {
rlens[0] = 0;
for (h = b = y = 0; y < width; y ) {
if ((b1 = qrframe[x width * y]) == b)
rlens[h] ;
else
rlens[ h] = 1;
b = b1;
}
thisbad = badruns(h);
}
return thisbad;
}
function genframe(instring) {
var x, y, k, t, v, i, j, m;
// find the smallest version that fits the string
t = instring.length;
version = 0;
do {
version ;
k = (ecclevel - 1) * 4 (version - 1) * 16;
neccblk1 = eccblocks[k ];
neccblk2 = eccblocks[k ];
datablkw = eccblocks[k ];
eccblkwid = eccblocks[k];
k = datablkw * (neccblk1 neccblk2) neccblk2 - 3 (version <= 9);
if (t <= k)
break;
} while (version < 40);
// FIXME - insure that it fits insted of being truncated
width = 17 4 * version;
// allocate, clear and setup data structures
v = datablkw (datablkw eccblkwid) * (neccblk1 neccblk2) neccblk2;
for (t = 0; t < v; t )
eccbuf[t] = 0;
strinbuf = instring.slice(0);
for (t = 0; t < width * width; t )
qrframe[t] = 0;
for (t = 0; t < (width * (width 1) 1) / 2; t )
framask[t] = 0;
// insert finders - black to frame, white to mask
for (t = 0; t < 3; t ) {
k = 0;
y = 0;
if (t == 1)
k = (width - 7);
if (t == 2)
y = (width - 7);
qrframe[(y 3) width * (k 3)] = 1;
for (x = 0; x < 6; x ) {
qrframe[(y x) width * k] = 1;
qrframe[y width * (k x 1)] = 1;
qrframe[(y 6) width * (k x)] = 1;
qrframe[(y x 1) width * (k 6)] = 1;
}
for (x = 1; x < 5; x ) {
setmask(y x, k 1);
setmask(y 1, k x 1);
setmask(y 5, k x);
setmask(y x 1, k 5);
}
for (x = 2; x < 4; x ) {
qrframe[(y x) width * (k 2)] = 1;
qrframe[(y 2) width * (k x 1)] = 1;
qrframe[(y 4) width * (k x)] = 1;
qrframe[(y x 1) width * (k 4)] = 1;
}
}
// alignment blocks
if (version > 1) {
t = adelta[version];
y = width - 7;
for (; ;) {
x = width - 7;
while (x > t - 3) {
putalign(x, y);
if (x < t)
break;
x -= t;
}
if (y <= t 9)
break;
y -= t;
putalign(6, y);
putalign(y, 6);
}
}
// single black
qrframe[8 width * (width - 8)] = 1;
// timing gap - mask only
for (y = 0; y < 7; y ) {
setmask(7, y);
setmask(width - 8, y);
setmask(7, y width - 7);
}
for (x = 0; x < 8; x ) {
setmask(x, 7);
setmask(x width - 8, 7);
setmask(x, width - 8);
}
// reserve mask-format area
for (x = 0; x < 9; x )
setmask(x, 8);
for (x = 0; x < 8; x ) {
setmask(x width - 8, 8);
setmask(8, x);
}
for (y = 0; y < 7; y )
setmask(8, y width - 7);
// timing row/col
for (x = 0; x < width - 14; x )
if (x & 1) {
setmask(8 x, 6);
setmask(6, 8 x);
}
else {
qrframe[(8 x) width * 6] = 1;
qrframe[6 width * (8 x)] = 1;
}
// version block
if (version > 6) {
t = vpat[version - 7];
k = 17;
for (x = 0; x < 6; x )
for (y = 0; y < 3; y , k--)
if (1 & (k > 11 ? version >> (k - 12) : t >> k)) {
qrframe[(5 - x) width * (2 - y width - 11)] = 1;
qrframe[(2 - y width - 11) width * (5 - x)] = 1;
}
else {
setmask(5 - x, 2 - y width - 11);
setmask(2 - y width - 11, 5 - x);
}
}
// sync mask bits - only set above for white spaces, so add in black bits
for (y = 0; y < width; y )
for (x = 0; x <= y; x )
if (qrframe[x width * y])
setmask(x, y);
// convert string to bitstream
// 8 bit data to QR-coded 8 bit data (numeric or alphanum, or kanji not supported)
v = strinbuf.length;
// string to array
for (i = 0; i < v; i )
eccbuf[i] = strinbuf.charCodeAt(i);
strinbuf = eccbuf.slice(0);
// calculate max string length
x = datablkw * (neccblk1 neccblk2) neccblk2;
if (v >= x - 2) {
v = x - 2;
if (version > 9)
v--;
}
// shift and repack to insert length prefix
i = v;
if (version > 9) {
strinbuf[i 2] = 0;
strinbuf[i 3] = 0;
while (i--) {
t = strinbuf[i];
strinbuf[i 3] |= 255 & (t << 4);
strinbuf[i 2] = t >> 4;
}
strinbuf[2] |= 255 & (v << 4);
strinbuf[1] = v >> 4;
strinbuf[0] = 0x40 | (v >> 12);
}
else {
strinbuf[i 1] = 0;
strinbuf[i 2] = 0;
while (i--) {
t = strinbuf[i];
strinbuf[i 2] |= 255 & (t << 4);
strinbuf[i 1] = t >> 4;
}
strinbuf[1] |= 255 & (v << 4);
strinbuf[0] = 0x40 | (v >> 4);
}
// fill to end with pad pattern
i = v 3 - (version < 10);
while (i < x) {
strinbuf[i ] = 0xec;
// buffer has room if (i == x) break;
strinbuf[i ] = 0x11;
}
// calculate and append ECC
// calculate generator polynomial
genpoly[0] = 1;
for (i = 0; i < eccblkwid; i ) {
genpoly[i 1] = 1;
for (j = i; j > 0; j--)
genpoly[j] = genpoly[j]
? genpoly[j - 1] ^ gexp[modnn(glog[genpoly[j]] i)] : genpoly[j - 1];
genpoly[0] = gexp[modnn(glog[genpoly[0]] i)];
}
for (i = 0; i <= eccblkwid; i )
genpoly[i] = glog[genpoly[i]]; // use logs for genpoly[] to save calc step
// append ecc to data buffer
k = x;
y = 0;
for (i = 0; i < neccblk1; i ) {
appendrs(y, datablkw, k, eccblkwid);
y = datablkw;
k = eccblkwid;
}
for (i = 0; i < neccblk2; i ) {
appendrs(y, datablkw 1, k, eccblkwid);
y = datablkw 1;
k = eccblkwid;
}
// interleave blocks
y = 0;
for (i = 0; i < datablkw; i ) {
for (j = 0; j < neccblk1; j )
eccbuf[y ] = strinbuf[i j * datablkw];
for (j = 0; j < neccblk2; j )
eccbuf[y ] = strinbuf[(neccblk1 * datablkw) i (j * (datablkw 1))];
}
for (j = 0; j < neccblk2; j )
eccbuf[y ] = strinbuf[(neccblk1 * datablkw) i (j * (datablkw 1))];
for (i = 0; i < eccblkwid; i )
for (j = 0; j < neccblk1 neccblk2; j )
eccbuf[y ] = strinbuf[x i j * eccblkwid];
strinbuf = eccbuf;
// pack bits into frame avoiding masked area.
x = y = width - 1;
k = v = 1; // up, minus
/* inteleaved data and ecc codes */
m = (datablkw eccblkwid) * (neccblk1 neccblk2) neccblk2;
for (i = 0; i < m; i ) {
t = strinbuf[i];
for (j = 0; j < 8; j , t <<= 1) {
if (0x80 & t)
qrframe[x width * y] = 1;
do { // find next fill position
if (v)
x--;
else {
x ;
if (k) {
if (y != 0)
y--;
else {
x -= 2;
k = !k;
if (x == 6) {
x--;
y = 9;
}
}
}
else {
if (y != width - 1)
y ;
else {
x -= 2;
k = !k;
if (x == 6) {
x--;
y -= 8;
}
}
}
}
v = !v;
} while (ismasked(x, y));
}
}
// save pre-mask copy of frame
strinbuf = qrframe.slice(0);
t = 0; // best
y = 30000; // demerit
// for instead of while since in original arduino code
// if an early mask was "good enough" it wouldn't try for a better one
// since they get more complex and take longer.
for (k = 0; k < 8; k ) {
applymask(k); // returns black-white imbalance
x = badcheck();
if (x < y) { // current mask better than previous best?
y = x;
t = k;
}
if (t == 7)
break; // don't increment i to a void redoing mask
qrframe = strinbuf.slice(0); // reset for next pass
}
if (t != k) // redo best mask - none good enough, last wasn't t
applymask(t);
// add in final mask/ecclevel bytes
y = fmtword[t ((ecclevel - 1) << 3)];
// low byte
for (k = 0; k < 8; k , y >>= 1)
if (y & 1) {
qrframe[(width - 1 - k) width * 8] = 1;
if (k < 6)
qrframe[8 width * k] = 1;
else
qrframe[8 width * (k 1)] = 1;
}
// high byte
for (k = 0; k < 7; k , y >>= 1)
if (y & 1) {
qrframe[8 width * (width - 7 k)] = 1;
if (k)
qrframe[(6 - k) width * 8] = 1;
else
qrframe[7 width * 8] = 1;
}
return qrframe;
}
var _canvas = null;
var api = {
get ecclevel() {
return ecclevel;
},
set ecclevel(val) {
ecclevel = val;
},
get size() {
return _size;
},
set size(val) {
_size = val
},
get canvas() {
return _canvas;
},
set canvas(el) {
_canvas = el;
},
getFrame: function (string) {
return genframe(string);
},
//这里的utf16to8(str)是对Text中的字符串进行转码，让其支持中文
utf16to8: function (str) {
var out, i, len, c;
out = "";
len = str.length;
for (i = 0; i < len; i ) {
c = str.charCodeAt(i);
if ((c >= 0x0001) && (c <= 0x007F)) {
out = str.charAt(i);
} else if (c > 0x07FF) {
out = String.fromCharCode(0xE0 | ((c >> 12) & 0x0F));
out = String.fromCharCode(0x80 | ((c >> 6) & 0x3F));
out = String.fromCharCode(0x80 | ((c >> 0) & 0x3F));
} else {
out = String.fromCharCode(0xC0 | ((c >> 6) & 0x1F));
out = String.fromCharCode(0x80 | ((c >> 0) & 0x3F));
}
}
return out;
},
/**
* 新增$this参数，传入组件的this,兼容在组件中生成
* @param bg 目前只能设置颜色值
*/
draw: function (str, ctx, startX, startY, cavW, cavH, bg, color, $this, ecc) {
var that = this;
ecclevel = ecc || ecclevel;
if (!ctx) {
console.warn('No canvas provided to draw QR code in!')
return;
}
var size = Math.min(cavW, cavH);
str = that.utf16to8(str);//增加中文显示
var frame = that.getFrame(str);
var px = size / width;
if (bg) {
ctx.setFillStyle(bg)
ctx.fillRect(startX, startY, cavW, cavW);
}
ctx.setFillStyle(color || 'black');
for (var i = 0; i < width; i ) {
for (var j = 0; j < width; j ) {
if (frame[j * width i]) {
ctx.fillRect(startX px * i, startY px * j, px, px);
}
}
}
}
}
module.exports = { api }
// exports.draw = api;
})();function isValidUrl(url) {
return /(ht|f)tp(s?)://([^ \/]*.) [^ \/]*(:[0-9] )?/?/.test(url);
}
/**
* 深度对比两个对象是否一致
* from: https://github.com/epoberezkin/fast-deep-equal
* @param {Object} a 对象a
* @param {Object} b 对象b
* @return {Boolean} 是否相同
*/
/* eslint-disable */
function equal(a, b) {
if (a === b) return true;
if (a && b && typeof a == 'object' && typeof b == 'object') {
var arrA = Array.isArray(a)
, arrB = Array.isArray(b)
, i
, length
, key;
if (arrA && arrB) {
length = a.length;
if (length != b.length) return false;
for (i = length; i-- !== 0;)
if (!equal(a[i], b[i])) return false;
return true;
}
if (arrA != arrB) return false;
var dateA = a instanceof Date
, dateB = b instanceof Date;
if (dateA != dateB) return false;
if (dateA && dateB) return a.getTime() == b.getTime();
var regexpA = a instanceof RegExp
, regexpB = b instanceof RegExp;
if (regexpA != regexpB) return false;
if (regexpA && regexpB) return a.toString() == b.toString();
var keys = Object.keys(a);
length = keys.length;
if (length !== Object.keys(b).length)
return false;
for (i = length; i-- !== 0;)
if (!Object.prototype.hasOwnProperty.call(b, keys[i])) return false;
for (i = length; i-- !== 0;) {
key = keys[i];
if (!equal(a[key], b[key])) return false;
}
return true;
}
return a!==a && b!==b;
}
module.exports = {
isValidUrl,
equal
};painter部分
代码语言：javascript复制import Pen from './lib/pen';
import Downloader from './lib/downloader';
const util = require('./lib/util');
const downloader = new Downloader();
// 最大尝试的绘制次数
const MAX_PAINT_COUNT = 5;
Component({
canvasWidthInPx: 0,
canvasHeightInPx: 0,
paintCount: 0,
/**
* 组件的属性列表
*/
properties: {
customStyle: {
type: String,
},
palette: {
type: Object,
observer: function (newVal, oldVal) {
if (this.isNeedRefresh(newVal, oldVal)) {
this.paintCount = 0;
this.startPaint();
}
},
},
// 启用脏检查，默认 false
dirty: {
type: Boolean,
value: false,
},
},
data: {
picURL: '',
showCanvas: true,
painterStyle: '',
},
attached() {
setStringPrototype();
},
methods: {
/**
* 判断一个 object 是否为 空
* @param {object} object
*/
isEmpty(object) {
for (const i in object) {
return false;
}
return true;
},
isNeedRefresh(newVal, oldVal) {
if (!newVal || this.isEmpty(newVal) || (this.data.dirty && util.equal(newVal, oldVal))) {
return false;
}
return true;
},
startPaint() {
if (this.isEmpty(this.properties.palette)) {
return;
}
if (!(getApp().systemInfo && getApp().systemInfo.screenWidth)) {
try {
getApp().systemInfo = wx.getSystemInfoSync();
} catch (e) {
const error = `Painter get system info failed, ${JSON.stringify(e)}`;
that.triggerEvent('imgErr', { error: error });
console.log(error);
return;
}
}
screenK = getApp().systemInfo.screenWidth / 750;
this.downloadImages().then((palette) => {
const { width, height } = palette;
this.canvasWidthInPx = width.toPx();
this.canvasHeightInPx = height.toPx();
if (!width || !height) {
console.log(`You should set width and height correctly for painter, width: ${width}, height: ${height}`);
return;
}
this.setData({
painterStyle: `width:${width};height:${height};`,
});
const ctx = wx.createCanvasContext('k-canvas', this);
const pen = new Pen(ctx, palette);
pen.paint(() => {
this.saveImgToLocal();
});
});
},
downloadImages() {
return new Promise((resolve, reject) => {
let preCount = 0;
let completeCount = 0;
const paletteCopy = JSON.parse(JSON.stringify(this.properties.palette));
if (paletteCopy.background) {
preCount ;
downloader.download(paletteCopy.background).then((path) => {
paletteCopy.background = path;
completeCount ;
if (preCount === completeCount) {
resolve(paletteCopy);
}
}, () => {
completeCount ;
if (preCount === completeCount) {
resolve(paletteCopy);
}
});
}
if (paletteCopy.views) {
let that = this
for (const view of paletteCopy.views) {
if (view && view.type === 'image' && view.url) {
preCount ;
/* eslint-disable no-loop-func */
downloader.download(view.url).then((path) => {
view.url = path;
wx.getImageInfo({
src: view.url,
success: (res) => {
// 获得一下图片信息，供后续裁减使用
view.sWidth = res.width;
view.sHeight = res.height;
},
fail: (error) => {
console.log(`imgDownloadErr failed, ${JSON.stringify(error)}`);
that.triggerEvent('imgDownloadErr', { error: error });
},
complete: () => {
completeCount ;
if (preCount === completeCount) {
resolve(paletteCopy);
}
},
});
}, () => {
completeCount ;
if (preCount === completeCount) {
resolve(paletteCopy);
}
});
}
}
}
if (preCount === 0) {
resolve(paletteCopy);
}
});
},
saveImgToLocal() {
const that = this;
setTimeout(() => {
wx.canvasToTempFilePath({
canvasId: 'k-canvas',
success: function (res) {
that.getImageInfo(res.tempFilePath);
},
fail: function (error) {
console.log(`canvasToTempFilePath failed, ${JSON.stringify(error)}`);
that.triggerEvent('imgErr', { error: error });
},
}, this);
}, 300);
},
getImageInfo(filePath) {
const that = this;
wx.getImageInfo({
src: filePath,
success: (infoRes) => {
if (that.paintCount > MAX_PAINT_COUNT) {
const error = `The result is always fault, even we tried ${MAX_PAINT_COUNT} times`;
console.log(error);
that.triggerEvent('imgErr', { error: error });
return;
}
// 比例相符时才证明绘制成功，否则进行强制重绘制
if (Math.abs((infoRes.width * that.canvasHeightInPx - that.canvasWidthInPx * infoRes.height) / (infoRes.height * that.canvasHeightInPx)) < 0.01) {
that.triggerEvent('imgOK', { path: filePath });
} else {
that.startPaint();
}
that.paintCount ;
},
fail: (error) => {
console.log(`getImageInfo failed, ${JSON.stringify(error)}`);
that.triggerEvent('imgErr', { error: error });
},
});
},
},
});
let screenK = 0.5;
function setStringPrototype() {
/* eslint-disable no-extend-native */
/**
* 是否支持负数
* @param {Boolean} minus 是否支持负数
*/
String.prototype.toPx = function toPx(minus) {
let reg;
if (minus) {
reg = /^-?[0-9] ([.]{1}[0-9] ){0,1}(rpx|px)$/g;
} else {
reg = /^[0-9] ([.]{1}[0-9] ){0,1}(rpx|px)$/g;
}
const results = reg.exec(this);
if (!this || !results) {
console.log(`The size: ${this} is illegal`);
return 0;
}
const unit = results[2];
const value = parseFloat(this);
let res = 0;
if (unit === 'rpx') {
res = Math.round(value * screenK);
} else if (unit === 'px') {
res = value;
}
return res;
};
}{
"component": true,
"usingComponents": {}
}<canvas canvas-id="k-canvas" style="{{painterStyle}}{{customStyle}}" />3、shareBox
代码语言：javascript复制Component({
properties: {
//属性值可以在组件使用时指定
isCanDraw: {
type: Boolean,
value: false,
observer(newVal, oldVal) {
newVal && this.drawPic()
}
}
},
data: {
isModal: false, //是否显示拒绝保存图片后的弹窗
imgDraw: {}, //绘制图片的大对象
sharePath: '', //生成的分享图
visible: false
},
methods: {
handlePhotoSaved() {
this.savePhoto(this.data.sharePath)
},
handleClose() {
this.setData({
visible: false
})
},
drawPic() {
if (this.data.sharePath) { //如果已经绘制过了本地保存有图片不需要重新绘制
this.setData({
visible: true
})
this.triggerEvent('initData')
return
}
wx.showLoading({
title: '生成中'
})
this.setData({
imgDraw: {
width: '750rpx',
height: '1334rpx',
background: 'https://cdn.nlark.com/yuque/0/2020/png/1252071/1586359267074-3d9d4922-d473-49db-8b14-e43d1d7d3e1a.png',
views: [
{
type: 'image',
url: 'https://cdn.nlark.com/yuque/0/2020/jpeg/1252071/1586359160786-8d5b7738-3ad3-43e7-bf0a-738c58365645.jpeg',//头图
css: {
top: '32rpx',
left: '30rpx',
right: '32rpx',
width: '688rpx',
height: '420rpx',
borderRadius: '16rpx'
},
},
{
type: 'image',
url: wx.getStorageSync('avatarUrl') || 'https://cdn.nlark.com/yuque/0/2020/png/1252071/1586358984220-88e904c6-345e-4d21-9960-6f26aaa85043.png',//用户头像
css: {
top: '404rpx',
left: '328rpx',
width: '96rpx',
height: '96rpx',
borderWidth: '6rpx',
borderColor: '#FFF',
borderRadius: '96rpx'
}
},
{
type: 'text',
text: wx.getStorageSync('nickName') || '匿名用户',
css: {
top: '532rpx',
fontSize: '28rpx',
left: '375rpx',
align: 'center',
color: '#3c3c3c'
}
},
{
type: 'text',
text: `邀请您参与助力活动`,
css: {
top: '576rpx',
left: '375rpx',
align: 'center',
fontSize: '28rpx',
color: '#3c3c3c'
}
},
{
type: 'text',
text: `这是一个view转canvas绘制的示例`,
css: {
top: '644rpx',
left: '375rpx',
maxLines: 1,
align: 'center',
fontWeight: 'bold',
fontSize: '44rpx',
color: '#3c3c3c'
}
},
{
type: 'image',
url: 'https://cdn.nlark.com/yuque/0/2020/jpeg/1252071/1586358913137-22be603f-99b1-4349-98bd-961d369b89e7.jpeg',//小程序码
css: {
top: '834rpx',
left: '470rpx',
width: '200rpx',
height: '200rpx'
}
}
]
}
})
},
onImgErr(e) {
wx.hideLoading()
wx.showToast({
title: '生成分享图失败，请刷新页面重试'
})
},
onImgOK(e) {
wx.hideLoading()
this.setData({
sharePath: e.detail.path,
visible: true,
})
//通知外部绘制完成，重置isCanDraw为false
this.triggerEvent('initData')
},
preventDefault() { },
// 保存图片
savePhoto(path) {
wx.showLoading({
title: '正在保存...',
mask: true
})
this.setData({
isDrawImage: false
})
wx.saveImageToPhotosAlbum({
filePath: path,
success: (res) => {
wx.showToast({
title: '保存成功',
icon: 'none'
})
setTimeout(() => {
this.setData({
visible: false
})
}, 300)
},
fail: (res) => {
wx.getSetting({
success: res => {
let authSetting = res.authSetting
if (!authSetting['scope.writePhotosAlbum']) {
this.setData({
isModal: true
})
}
}
})
setTimeout(() => {
wx.hideLoading()
this.setData({
visible: false
})
}, 300)
}
})
}
}
}){
"component": true,
"usingComponents": {
"painter": "../painter/painter",
"dialog-modal": "../dialogModal/index"
}
}<view class="share-wrap" wx:if="{{visible}}" catchtouchmove="preventDefault">
<view class="share-back"></view>
<view class="share-container">
<view class="close" bindtap="handleClose" data-ptpid="ebe9-1656-ad6a-462e"></view>
<image mode="widthFix" src="{{sharePath}}" class="share-image" />
<view class="share-tips">保存图片，叫伙伴们来参与吧</view>
<view class="save-btn" bindtap="handlePhotoSaved" data-ptpid="4095-16fd-bc97-4868"></view>
</view>
</view>
<painter style="position: absolute; top: -9999rpx;" palette="{{imgDraw}}" bind:imgOK="onImgOK" />
<dialog-modal isShow="{{isModal}}" title="提示" content="您未开启保存图片到相册的权限，请点击确定去开启权限！" confirmType="openSetting" />.share-wrap {
width: 100%;
}
.share-back {
width: 100%;
height: 100%;
background: rgba(0, 0, 0, 0.6);
position: fixed;
top: 0;
left: 0;
right: 0;
bottom: 0;
z-index: 888;
}
.share-container {
width: 100%;
background: #FFF;
position: fixed;
bottom: 0;
left: 0;
right: 0;
z-index: 999;
}
.close {
width: 30rpx;
height: 30rpx;
overflow: hidden;
position: absolute;
right: 64rpx;
top: 64rpx;
}
.close::after {
transform: rotate(-45deg);
}
.close::before {
transform: rotate(45deg);
}
.close::before,
.close::after {
content: '';
position: absolute;
height: 3rpx;
width: 100%;
top: 50%;
left: 0;
margin-top: -2rpx;
background: #9C9C9C;
}
.share-image {
width: 420rpx;
margin: 66rpx auto 0;
display: block;
border-radius: 16rpx;
box-shadow: 0px 4rpx 8px 0px rgba(0, 0, 0, 0.1);
}
.share-tips {
width: 100%;
text-align: center;
color: #3C3C3C;
font-size: 28rpx;
margin: 32rpx 0;
}
.save-btn {
width: 336rpx;
height: 96rpx;
margin: 0 auto 94rpx;
background: url('https://qiniu-image.qtshe.com/20190506save-btn.png') center center;
background-size: 100% 100%;
}2.组件的使用
代码语言：javascript复制const app = getApp()
Page({
data: {
nickName: '',
avatarUrl: '',
isCanDraw: false
},
onLoad() {
this.setData({
nickName: wx.getStorageSync('nickName') || '',
avatarUrl: wx.getStorageSync('avatarUrl') || ''
})
},
getUserInfo(e) {
this.setData({
nickName: e.detail.userInfo.nickName,
avatarUrl: e.detail.userInfo.avatarUrl
})
wx.setStorageSync('avatarUrl', e.detail.userInfo.avatarUrl)
wx.setStorageSync('nickName', e.detail.userInfo.nickName)
},
createShareImage() {
this.setData({
isCanDraw: !this.data.isCanDraw
})
},
}){
"usingComponents": {
"share-box": "./components/shareBox/index"
}
}<view class="section">
<!-- 生成分享图，将view转绘为图片 -->
<button type="primary" class="intro" open-type="getUserInfo" bindgetuserinfo="getUserInfo" wx:if="{{!nickName}}">获取分享图头像昵称</button>
<button type="primary" class="intro" bindtap="createShareImage" wx:else>点我生成分享图</button>
<share-box isCanDraw="{{isCanDraw}}" bind:initData="createShareImage" />
</view>3.效果
