iOS-Quartz2D画图

常说温故而知新,时隔这么久再次看这些基础内容仍然很兴奋!把敲的代码分享出来,希望能对读者提供一丁点启发

/**
 *  裁剪圆形图片
 */
-(void)circleicon{
    uiimage *image = [uiimage imagenamed:@"baby"];
    uigraphicsbeginimagecontext(image.size);
    uibezierpath *path = [uibezierpath bezierpathwithovalinrect:cgrectmake(0, 0, image.size.width, image.size.height)];
    [path addclip];
    [image drawatpoint:cgpointzero];
    uiimage *newimage = uigraphicsgetimagefromcurrentimagecontext();
    uigraphicsendimagecontext();
    self.imagev.image = newimage;
}

/**
 *  图片加水印
 */
-(void)watermark{

    uiimage *image= [uiimage imagenamed:@"baby"];

    //开启图片上下文
    uigraphicsbeginimagecontextwithoptions(image.size, no, 0.0);
    //将图片绘制到图片上下文
    [image drawatpoint:cgpointzero];
    //绘制文字
    nsstring *str = @"邱学伟";
    [str drawatpoint:cgpointzero withattributes:@{nsfontattributename:[uifont systemfontofsize:20]}];
    //生成图片
    uiimage *newimage = uigraphicsgetimagefromcurrentimagecontext();
    //手动关闭上下文
    uigraphicsendimagecontext();

    self.imagev.image = newimage;

}



-(void)awakefromnib{
//    [self timer];
}



/**
 *  图形上下文矩阵操作
 */
-(void)drawmatrix{
    //1.开启一个上下文
    cgcontextref ctx = uigraphicsgetcurrentcontext();
    //2.绘制路径
    uibezierpath *path = [uibezierpath bezierpathwithovalinrect:cgrectmake(100, 100, 200, 100)];
    [[uicolor redcolor] set];

    //上下文矩阵操作
    //平移
//    cgcontexttranslatectm(ctx, -50, -50);

    //缩放
    cgcontextscalectm(ctx, 0.5, 0.5);

    //旋转
    cgcontextrotatectm(ctx, m_pi_4);

    //3.将路径添加到图形上下文
    cgcontextaddpath(ctx, path.cgpath);
    //4.把上下水渲染出来
    cgcontextfillpath(ctx);
}


/**
 *  定时器下雪
 */
-(void)timer{
    //定时器方法1-卡顿
//    nstimer *timer = [nstimer scheduledtimerwithtimeinterval:0.02 target:self selector:@selector(updatesnow) userinfo:nil repeats:yes];

    //定时器方法2-在屏幕每次刷新(没秒刷新60次)时调用
    cadisplaylink *link = [cadisplaylink displaylinkwithtarget:self selector:@selector(updatesnow)];
    [link addtorunloop:[nsrunloop mainrunloop] formode:nsdefaultrunloopmode];

}
-(void)updatesnow{
    _y+=10;
    if (_y > self.bounds.size.height) {
        _y = 0;
    }
    [self setneedsdisplay];
}
static int _y = 0;

/**
 *  画图片
 */
-(void)drawimagewith:(cgrect)rect{
    uiimage *image = [uiimage imagenamed:@"snow"];
    //保持图片源尺寸
    [image drawatpoint:cgpointmake(10, _y)];
    //填充整个view
//    [image drawinrect:self.bounds];
    //把image画满整个view
//    [image drawaspatterninrect:self.bounds];
}


/**
 *  画文字
 */
-(void)drawtextwith:(cgrect)rect{
    nsstring *str = @"邱学伟";
    nsmutabledictionary *attri = [nsmutabledictionary dictionary];
    [attri setobject:[uifont systemfontofsize:50] forkey:nsfontattributename];
    [attri setobject:[uicolor whitecolor] forkey:nsforegroundcolorattributename];
    //不会自动换行
    [str drawatpoint:cgpointzero withattributes:attri];
    //会自动换行
    [str drawinrect:rect withattributes:attri];
}

/**
 *  画饼图
 */
-(void)drawprewithrect:(cgrect)rect{
    nsarray *anglearr = @[@25,@25,@50];
    cgpoint center = cgpointmake(rect.size.width*0.5, rect.size.height*0.5);
    cgfloat radius = rect.size.width*0.5-10;
    cgfloat angle = 0;
    cgfloat startangle = 0;
    cgfloat endangle = 0;

    for (nsnumber *num in anglearr) {
        startangle = endangle;
        angle = num.intvalue/100.0*m_pi*2;
        endangle = startangle + angle;
        uibezierpath *path = [uibezierpath bezierpathwitharccenter:center radius:radius startangle:startangle endangle:endangle clockwise:yes];
        [path addlinetopoint:center];
        [[self randomcolor] set];
        [path fill];
    }

}
//随机颜色
-(uicolor *)randomcolor{
    cgfloat r = arc4random_uniform(256) / 255.0;
    cgfloat g = arc4random_uniform(256) / 255.0;
    cgfloat b = arc4random_uniform(256) / 255.0;
    return [uicolor colorwithred:r green:g blue:b alpha:1];
}


/**
 *  画进度条
 */
-(void)setprogressvalue:(cgfloat)progressvalue{
    if (_progressvalue != progressvalue) {
        _progressvalue = progressvalue;
        [self setneedsdisplay];
    }
}
-(void)drawprogresswithrect:(cgrect)rect{
    cgpoint center = cgpointmake(rect.size.width*0.5, rect.size.height*0.5);
    cgfloat radius = rect.size.width*0.5-10;
    cgfloat startangle = -m_pi_2;
    cgfloat endangle = -m_pi_2 + self.progressvalue*m_pi*2;
    uibezierpath *progresspath = [uibezierpath bezierpathwitharccenter:center radius:radius startangle:startangle endangle:endangle clockwise:yes];
    [progresspath stroke];
}

/**
 *  画圆和圆弧
 */
-(void)drawcirclewithrect:(cgrect)rect{
    //1. radius - 圆角半径
    uibezierpath *circel0 = [uibezierpath bezierpathwithroundedrect:cgrectmake(20, 20, 100, 100) cornerradius:10];
    //    [circel0 stroke];

    uibezierpath *circle1 = [uibezierpath bezierpathwithovalinrect:cgrectmake(20, 20, 100, 100)];
    //    [circle1 fill];

    //画弧
    //center:圆心
    //radius:半径
    //startangle:开始角度 0:圆右侧
    //endangle:结束角度
    //clockwise yes:顺时针  no:逆时针
    cgpoint center = cgpointmake(rect.size.width*0.5, rect.size.height*0.5);
    uibezierpath *path = [uibezierpath bezierpathwitharccenter:cgpointmake(rect.size.width*0.5, rect.size.height*0.5) radius:50 startangle:0 endangle:-m_pi_2 clockwise:no];
    [path addlinetopoint:center];
    //    [path addlinetopoint:cgpointmake(center.x+50, center.y)];
    //上行代码可以使用封闭路径
    [path closepath];
    [path stroke];

}

/**
 *  画矩形
 */
-(void)drawrect{
    cgcontextref contextref = uigraphicsgetcurrentcontext();
    uibezierpath *path = [uibezierpath bezierpathwithrect:cgrectmake(10, 10, 100, 100)];
    cgcontextaddpath(contextref, path.cgpath);
    cgcontextstrokepath(contextref);
}

/**
 *  画圆
 */
-(void)drawquadcurve{
    cgcontextref textref = uigraphicsgetcurrentcontext();
    uibezierpath *path = [uibezierpath bezierpath];
    [path movetopoint:cgpointmake(20, 180)];
    [path addquadcurvetopoint:cgpointmake(200, 180) controlpoint:cgpointmake(110, 10)];
    cgcontextsetlinewidth(textref, 10);
    cgcontextaddpath(textref, path.cgpath);
    cgcontextstrokepath(textref);
}

/**
 *  画线
 */
-(void)drawline{
    //1.取得一个跟view相关的上下文
    cgcontextref contextrex = uigraphicsgetcurrentcontext();
    //2.1 描述路径
    uibezierpath *bezierpath = [uibezierpath bezierpath];
    //2.2 设置起点
    [bezierpath movetopoint:cgpointmake(10, 100)];
    //2.3 设置终点
    [bezierpath addlinetopoint:cgpointmake(100, 20)];
    //2.4再设置一个终点
    [bezierpath addlinetopoint:cgpointmake(100, 100)];

    //*设置路径属性 - 上下文状态
    //宽度
    cgcontextsetlinewidth(contextrex, 10);
    //线的连接样式
    //    kcglinejoinmiter, 默认
    //    kcglinejoinround, 圆弧
    //    kcglinejoinbevel  方形
    cgcontextsetlinejoin(contextrex, kcglinejoinbevel);
    //颜色
    [[uicolor redcolor] setstroke];

    //3.把路径添加到上下文
    cgcontextaddpath(contextrex, bezierpath.cgpath);
    //4.把上下文显示在view上
    cgcontextstrokepath(contextrex);

}