reader/components/yeyouzi-cropper/yeyouzi-cropper.js

// components/yeyouzi-cropper/yeyouzi-cropper.js
let success;
let fail;
Component({
    /**
     * 组件的属性列表
     */
    properties: {

    },

    /**
     * 组件的初始数据
     */
    data: {
        canvas: '',
        ctx: '',
        dpr: '',
        x1: 0,
        y1: 0,
        x2: 0,
        y2: 0,
        k1: 0,
        m1: 0,
        k2: 0,
        m2: 0,
        cutMove: false,
        endCut: {
            x: 0,
            y: 0
        },
        movePoint: '0',
        img: {
            path: '',
            width: 0,
            height: 0,
            type: 1 // 1:横向 2:纵向
        },
        imageWidth: 0,
        imageHeight: 0,
        imageLeft: 0,
        imageTop: 0,
        imgRotate: 0,
        imgMirror: 0,
        originWidthShow: 0.5,
        originHeightShow: 0.5,
        imgMove: false,
        imgStart: {
            x: 0,
            y: 0,
            left: 0,
            top: 0,
            distance: 0,
            width: 0,
            height: 0,
            cutImg: ''
        },
        imgScale: false,

        cutImg: {
            path: '',
            x: 0,
            y: 0,
            width: 0,
            height: 0
        }


    },

    /**
     * 组件的方法列表
     */
    methods: {
        /**
         * 公有方法
         */

        //初始化
        init(param) {
            success = param.success
            fail = param.fail
            var that = this;
            this.setData({
                img: {
                    path: param.imgPath
                }
            })
            const query = wx.createSelectorQuery().in(this)
            query.select('#cutCanvas')
                .fields({
                    node: true,
                    size: true
                })
                .exec((res) => {
                    const canvas = res[0].node
                    const ctx = canvas.getContext('2d')
                    const dpr = 0.84
                    canvas.width = res[0].width * dpr
                    canvas.height = res[0].height * dpr
                    ctx.scale(dpr, dpr)

                    var x1 = canvas.width * 0.15 / dpr;
                    var y1 = (canvas.height - canvas.width * 0.7) / 2 / dpr;
                    var x2 = x1 + canvas.width * 0.7 / dpr;
                    var y2 = y1 + canvas.width * 0.7 / dpr;
                    var k1 = (y2 - y1) / (x2 - x1);
                    var m1 = (x2 * y1 - x1 * y2) / (x2 - x1)
                    var k2 = (y1 - y2) / (x2 - x1);
                    var m2 = (x2 * y2 - x1 * y1) / (x2 - x1);
                    that.setData({
                        canvas: canvas,
                        ctx: ctx,
                        dpr: dpr,
                        x1: x1,
                        y1: y1,
                        x2: x2,
                        y2: y2,
                        k1: k1,
                        m1: m1,
                        k2: k2,
                        m2: m2
                    })
                    this._drawCut(x1, y1, x2, y2)
                    wx.getImageInfo({
                        src: param.imgPath,
                        success(img) {
                            var width = '';
                            var height = '';
                            var type = 0;
                            var x = '';
                            var y = '';
                            var d = '';
                            if (img.width > img.height) {
                                height = that.data.y2 - that.data.y1;
                                width = (img.width * height) / img.height
                                type = 1
                                d = img.height
                                x = (img.width - d) / 2
                                y = 0
                            } else {
                                width = that.data.x2 - that.data.x1;
                                height = (img.height * width) / img.width
                                type = 2
                                d = img.width
                                x = 0
                                y = (img.height - d) / 2
                            }
                            that.setData({
                                img: {
                                    path: param.imgPath,
                                    width: img.width,
                                    height: img.height,
                                    type: type
                                },
                                cutImg: {
                                    x: x,
                                    y: y,
                                    width: d,
                                    height: d
                                },
                                imageWidth: ((x2 - x1) / d) * img.width,
                                imageHeight: ((y2 - y1) / d) * img.height,
                                imageLeft: x1 - ((x2 - x1) / d) * x,
                                imageTop: y1 - ((y2 - y1) / d) * y,
                                imgRotate: 0
                            })
                        }
                    })
                })

        },

        /**
         * 私有方法
         */
        _drawCut(x1, y1, x2, y2) {
            var ctx = this.data.ctx;
            var canvas = this.data.canvas;
            ctx.clearRect(0, 0, canvas.width, canvas.height)
            ctx.globalAlpha = '0.5'
            ctx.fillStyle = '#000000'
            ctx.fillRect(0, 0, canvas.width, canvas.height)

            ctx.strokeStyle = '#ffffff'
            ctx.lineWidth = '3'
            ctx.lineCap = 'square'
            ctx.globalAlpha = '1'
            ctx.strokeRect(x1, y1, x2 - x1, y2 - y1)
            ctx.fillStyle = '#ffffff'
            ctx.fillRect(x1 - 5, y1 - 5, 20, 20) //左上角 1
            ctx.fillRect(x2 - 15, y1 - 5, 20, 20) //右上角 2
            ctx.fillRect(x1 - 5, y2 - 15, 20, 20) //左下角 3
            ctx.fillRect(x2 - 15, y2 - 15, 20, 20) //右下角 4
            ctx.clearRect(x1, y1, x2 - x1, y2 - y1)
        },

        _touchStart(e) {
            //裁剪框是否移动
            var flag = false;
            var point = '0'
            if (e.touches[0].x >= this.data.x1 - 10 && this.data.x1 + 10 >= e.touches[0].x) {
                if (e.touches[0].y >= this.data.y1 - 10 && this.data.y1 + 10 >= e.touches[0].y) {
                    flag = true;
                    point = '1';
                    this.setData({
                        endCut: {
                            x: this.data.x1,
                            y: this.data.y1
                        }
                    })
                } else if (e.touches[0].y >= this.data.y2 - 10 && this.data.y2 + 10 >= e.touches[0].y) {
                    flag = true;
                    point = '3';
                    this.setData({
                        endCut: {
                            x: this.data.x1,
                            y: this.data.y2
                        }
                    })
                }
            } else if (e.touches[0].x >= this.data.x2 - 10 && this.data.x2 + 10 >= e.touches[0].x) {
                if (e.touches[0].y >= this.data.y1 - 10 && this.data.y1 + 10 >= e.touches[0].y) {
                    flag = true;
                    point = '2'
                    this.setData({
                        endCut: {
                            x: this.data.x2,
                            y: this.data.y1
                        }
                    })
                } else if (e.touches[0].y >= this.data.y2 - 10 && this.data.y2 + 10 >= e.touches[0].y) {
                    flag = true;
                    point = '4'
                    this.setData({
                        endCut: {
                            x: this.data.x2,
                            y: this.data.y2
                        }
                    })
                }
            }
            this.setData({
                cutMove: flag,
                movePoint: point
            })

            //图片是否移动
            if (e.touches[0].x >= this.data.x1 + 10 && this.data.x2 - 10 >= e.touches[0].x) {
                if (e.touches[0].y >= this.data.y1 + 10 && this.data.y2 - 10 >= e.touches[0].y) {
                    if (e.touches.length == 1) {
                        this.setData({
                            imgMove: true,
                            imgStart: {
                                x: e.touches[0].x,
                                y: e.touches[0].y,
                                left: this.data.imageLeft,
                                top: this.data.imageTop
                            },
                            imgScale: false
                        })
                    } else if (e.touches.length == 2) {
                        this.setData({
                            imgMove: false,
                            imgStart: {
                                distance: Math.sqrt(Math.pow(e.touches[1].x - e.touches[0].x, 2) + Math.pow(e.touches[1].y - e.touches[0].y, 2)),
                                width: this.data.imageWidth,
                                height: this.data.imageHeight,
                                cutImg: this.data.cutImg
                            },
                            imgScale: true
                        })
                    }
                }
            }
        },

        _touchMove(e) {
            if (this.data.cutMove) {
                var x1;
                var y1;
                var x2;
                var y2;
                if (this.data.movePoint == '1') {
                    x1 = e.touches[0].x
                    y1 = this.data.k1 * x1 + this.data.m1
                    x2 = this.data.x2
                    y2 = this.data.y2
                    if (x1 > x2 - 100) {
                        x1 = x2 - 100
                        y1 = this.data.k1 * x1 + this.data.m1
                    } else if (x1 < this.data.x1) {
                        x1 = this.data.x1
                        y1 = this.data.k1 * x1 + this.data.m1
                    }
                    this.setData({
                        endCut: {
                            x: x1,
                            y: y1
                        }
                    })
                } else if (this.data.movePoint == '2') {
                    x2 = e.touches[0].x
                    y1 = this.data.k2 * x2 + this.data.m2
                    x1 = this.data.x1
                    y2 = this.data.y2
                    if (x2 > this.data.x2) {
                        x2 = this.data.x2
                        y1 = this.data.y1
                    } else if (x2 < this.data.x1 + 100) {
                        x2 = this.data.x1 + 100
                        y1 = this.data.k2 * x2 + this.data.m2
                    }
                    this.setData({
                        endCut: {
                            x: x2,
                            y: y1
                        }
                    })
                } else if (this.data.movePoint == '3') {
                    x1 = e.touches[0].x
                    y2 = this.data.k2 * x1 + this.data.m2
                    x2 = this.data.x2
                    y1 = this.data.y1
                    if (x1 > x2 - 100) {
                        x1 = x2 - 100
                        y2 = this.data.k2 * x1 + this.data.m2
                    } else if (x1 < this.data.x1) {
                        x1 = this.data.x1
                        y2 = this.data.y2
                    }
                    this.setData({
                        endCut: {
                            x: x1,
                            y: y2
                        }
                    })
                } else if (this.data.movePoint == '4') {
                    x2 = e.touches[0].x
                    y2 = this.data.k1 * x2 + this.data.m1
                    x1 = this.data.x1
                    y1 = this.data.y1
                    if (x2 > this.data.x2) {
                        x2 = this.data.x2
                        y2 = this.data.k1 * x2 + this.data.m1
                    } else if (x2 < x1 + 100) {
                        x2 = x1 + 100
                        y2 = this.data.k1 * x2 + this.data.m1
                    }
                    this.setData({
                        endCut: {
                            x: x2,
                            y: y2
                        }
                    })
                }
                this._drawCut(x1, y1, x2, y2)
            } else if (this.data.imgMove) {
                var dx = this.data.imgStart.x - e.touches[0].x
                var dy = this.data.imgStart.y - e.touches[0].y
                var rotate = this.data.imgRotate
                var left = this.data.imgStart.left - dx
                var top = this.data.imgStart.top - dy
                if (this.data.imgMirror == 180) {
                    dx = -dx
                    rotate = -rotate
                }
                var tx = dx * Math.cos(rotate * Math.PI / 180) + dy * Math.sin(rotate * Math.PI / 180)
                var ty = dy * Math.cos(rotate * Math.PI / 180) - dx * Math.sin(rotate * Math.PI / 180)
                var x = (tx + this.data.originWidthShow * this.data.imageWidth) / this.data.imageWidth * this.data.img.width - this.data.cutImg.width / 2
                var y = (ty + this.data.originHeightShow * this.data.imageHeight) / this.data.imageHeight * this.data.img.height - this.data.cutImg.height / 2
                this.setData({
                    cutImg: {
                        width: this.data.cutImg.width,
                        height: this.data.cutImg.height,
                        x: x,
                        y: y
                    },
                    imageLeft: left,
                    imageTop: top,
                })
            } else if (this.data.imgScale) {
                var nowDistance = Math.sqrt(Math.pow(e.touches[1].x - e.touches[0].x, 2) + Math.pow(e.touches[1].y - e.touches[0].y, 2))
                var m = nowDistance / this.data.imgStart.distance
                var width = this.data.imgStart.width * m
                var height = this.data.imgStart.height * m
                if (this.data.img.type == 1) {
                    height = height < this.data.y2 - this.data.y1 ? this.data.y2 - this.data.y1 : height
                    height = height > (this.data.y2 - this.data.y1) * 10 ? (this.data.y2 - this.data.y1) * 10 : height
                    width = (height * this.data.img.width) / this.data.img.height
                } else {
                    width = width < this.data.x2 - this.data.x1 ? this.data.x2 - this.data.x1 : width
                    width = width > (this.data.x2 - this.data.x1) * 10 ? (this.data.x2 - this.data.x1) * 10 : width
                    height = (width * this.data.img.height) / this.data.img.width
                }
                var n = width / this.data.imgStart.width
                var cut = {
                    x: this.data.imgStart.cutImg.x + ((n - 1) / (2 * n)) * this.data.imgStart.cutImg.width,
                    y: this.data.imgStart.cutImg.y + ((n - 1) / (2 * n)) * this.data.imgStart.cutImg.height,
                    width: this.data.imgStart.cutImg.width / n,
                    height: this.data.imgStart.cutImg.height / n
                }
                var left = this.data.x1 - ((this.data.x2 - this.data.x1) / cut.width) * cut.x
                left = left > this.data.x1 ? this.data.x1 : left
                left = left < this.data.x2 - this.data.imageWidth ? this.data.x2 - this.data.imageWidth : left
                var top = this.data.y1 - ((this.data.y2 - this.data.y1) / cut.height) * cut.y
                top = top > this.data.y1 ? this.data.y1 : top
                top = top < this.data.y2 - this.data.imageHeight ? this.data.y2 - this.data.imageHeight : top
                this.setData({
                    imageLeft: left,
                    imageTop: top,
                    imageWidth: width,
                    imageHeight: height,
                    cutImg: {
                        x: cut.x,
                        y: cut.y,
                        width: cut.width,
                        height: cut.height
                    },
                })
            }
        },

        _touchEnd(e) {
            if (this.data.cutMove) {
                var dx;
                var dy;
                var d;
                var movePoint = this.data.movePoint
                if (movePoint % 2 == 0) {
                    d = ((this.data.endCut.x - this.data.x1) * this.data.cutImg.width) / (this.data.x2 - this.data.x1)
                    if (this.data.imgMirror == 180) {
                        dx = -(this.data.endCut.x - this.data.x2) / this.data.imageWidth * this.data.img.width / 2
                        if (movePoint == '2') {
                            dy = (this.data.endCut.y - this.data.y1) / this.data.imageHeight * this.data.img.height / 2
                        } else {
                            dy = (this.data.endCut.y - this.data.y2) / this.data.imageHeight * this.data.img.height / 2
                        }
                    } else {
                        dx = (this.data.endCut.x - this.data.x2) / this.data.imageWidth * this.data.img.width / 2
                        if (movePoint == '2') {
                            dy = (this.data.endCut.y - this.data.y1) / this.data.imageHeight * this.data.img.height / 2
                        } else {
                            dy = (this.data.endCut.y - this.data.y2) / this.data.imageHeight * this.data.img.height / 2
                        }
                    }
                } else {
                    d = ((this.data.x2 - this.data.endCut.x) * this.data.cutImg.width) / (this.data.x2 - this.data.x1)
                    if (this.data.imgMirror == 180) {
                        dx = -(this.data.endCut.x - this.data.x1) / this.data.imageWidth * this.data.img.width / 2
                        if (movePoint == '1') {
                            dy = (this.data.endCut.y - this.data.y1) / this.data.imageHeight * this.data.img.height / 2
                        } else {
                            dy = (this.data.endCut.y - this.data.y2) / this.data.imageHeight * this.data.img.height / 2
                        }
                    } else {
                        dx = (this.data.endCut.x - this.data.x1) / this.data.imageWidth * this.data.img.width / 2
                        if (movePoint == '1') {
                            dy = (this.data.endCut.y - this.data.y1) / this.data.imageHeight * this.data.img.height / 2
                        } else {
                            dy = (this.data.endCut.y - this.data.y2) / this.data.imageHeight * this.data.img.height / 2
                        }
                    }
                }
                var rotate = this.data.imgMirror == 180 ? -this.data.imgRotate : this.data.imgRotate
                var x = ((dx * Math.cos(rotate * Math.PI / 180) + dy * Math.sin(rotate * Math.PI / 180)) + this.data.originWidthShow * this.data.img.width) - d / 2
                var y = ((dy * Math.cos(rotate * Math.PI / 180) - dx * Math.sin(rotate * Math.PI / 180)) + this.data.originHeightShow * this.data.img.height) - d / 2
                this.setData({
                    cutImg: {
                        x: x,
                        y: y,
                        width: d,
                        height: d
                    },
                    imageWidth: ((this.data.x2 - this.data.x1) / d) * this.data.img.width,
                    imageHeight: ((this.data.y2 - this.data.y1) / d) * this.data.img.height,
                    imageLeft: this.data.x1 - ((this.data.x2 - this.data.x1) / d) * x,
                    imageTop: this.data.y1 - ((this.data.y2 - this.data.y1) / d) * y,

                })
                this._drawCut(this.data.x1, this.data.y1, this.data.x2, this.data.y2)
            }
            if (this.data.imgMove) {
                var left = this.data.x1 - ((this.data.x2 - this.data.x1) / this.data.cutImg.width) * this.data.cutImg.x
                var top = this.data.y1 - ((this.data.y2 - this.data.y1) / this.data.cutImg.height) * this.data.cutImg.y
                this.setData({
                    imageLeft: left,
                    imageTop: top,
                })
            }
            this.setData({
                originWidthShow: (this.data.cutImg.x + this.data.cutImg.width / 2) / this.data.img.width,
                originHeightShow: (this.data.cutImg.y + this.data.cutImg.height / 2) / this.data.img.height,
                cutMove: false,
                movePoint: '0',
                imgMove: false,
                imgScale: false
            })
        },

        _rotateChange(e) {
            this.setData({
                imgRotate: e.detail.value
            })
        },

        /*  _rotateNinety() {
             var r = this.data.imgRotate + 90 > 180 ? this.data.imgRotate - 270 : this.data.imgRotate + 90
             this.setData({
                 imgRotate: r
             })
         }, */

        /*   _imageMirror() {
              var m = this.data.imgMirror == 180 ? 0 : 180
              this.setData({
                  imgMirror: m,
              })
          }, */

        /*   _imgRestore(){
            this.setData({
              canvas: '',
              ctx: '',
              x1: 0,
              y1: 0,
              x2: 0,
              y2: 0,
              k1: 0,
              m1: 0,
              k2: 0,
              m2: 0,
              cutMove: false,
              endCut: {
                x: 0,
                y: 0
              },
              movePoint: '0',
              imageWidth: 0,
              imageHeight: 0,
              imageLeft: 0,
              imageTop: 0,
              imgRotate: 0,
              imgMirror: 0,
              originWidthShow: 0.5,
              originHeightShow: 0.5,
              imgMove: false,
              imgStart: {
                x: 0,
                y: 0,
                left: 0,
                top: 0,
                distance: 0,
                width: 0,
                height: 0,
                cutx: 0,
                cuty: 0
              },
              imgScale: false,
              cutImg: {
                path: '',
                x: 0,
                y: 0,
                width: 0,
                height: 0
              }
            })
            this.init(this.data.img.path)
          }, */

        _cancelCut() {
            this._restoreData()
            if (fail) {
                fail('cancel')
            }
        },

        _confirmCut() {
            wx.showLoading({
                title: '裁剪中...',
                mask: true
            })
            var that = this
            const query = wx.createSelectorQuery().in(this)
            query.select('#imgCanvas')
                .fields({
                    node: true,
                    size: true
                })
                .exec((res) => {
                    const canvas = res[0].node
                    const ctx = canvas.getContext('2d')
                    canvas.width = that.data.cutImg.width
                    canvas.height = that.data.cutImg.height
                    ctx.translate(canvas.width / 2, canvas.height / 2)
                    ctx.rotate((that.data.imgRotate >= 0 ? that.data.imgRotate : that.data.imgRotate + 360) * Math.PI / 180)
                    if (that.data.imgMirror == 180) {
                        ctx.scale(-1, 1); //左右镜像翻转
                    }
                    const img = canvas.createImage()
                    img.src = that.data.img.path
                    img.onload = () => {
                        ctx.drawImage(img, 0, 0, that.data.img.width, that.data.img.height, -(that.data.cutImg.x + canvas.width / 2), -(that.data.cutImg.y + canvas.height / 2), that.data.img.width, that.data.img.height)
                        wx.canvasToTempFilePath({
                            canvas: canvas,
                            success(img) {
                                success(img.tempFilePath)
                                that._restoreData()
                                wx.hideLoading({
                                    success: (res) => {},
                                })
                            },
                            fail(res) {
                                console.log(res, '裁剪失败');
                                wx.hideLoading({
                                    success: (res) => {
                                        wx.showToast({
                                            title: '裁剪失败',
                                            icon: 'error'
                                        })
                                        if (fail) {
                                            fail('fail')
                                        }
                                    },
                                })
                            }
                        })
                    }
                })

        },

        _restoreData() {
            this.setData({
                canvas: '',
                ctx: '',
                x1: 0,
                y1: 0,
                x2: 0,
                y2: 0,
                k1: 0,
                m1: 0,
                k2: 0,
                m2: 0,
                cutMove: false,
                endCut: {
                    x: 0,
                    y: 0
                },
                movePoint: '0',
                img: {
                    path: '',
                    width: 0,
                    height: 0,
                    type: 1 // 1:横向 2:纵向
                },
                imageWidth: 0,
                imageHeight: 0,
                imageLeft: 0,
                imageTop: 0,
                imgRotate: 0,
                imgMirror: 0,
                originWidthShow: 0.5,
                originHeightShow: 0.5,
                imgMove: false,
                imgStart: {
                    x: 0,
                    y: 0,
                    left: 0,
                    top: 0,
                    distance: 0,
                    width: 0,
                    height: 0,
                    cutx: 0,
                    cuty: 0
                },
                imgScale: false,

                cutImg: {
                    path: '',
                    x: 0,
                    y: 0,
                    width: 0,
                    height: 0
                }
            })
        },
    }
})