Quartz 2D小Demo

UI › 摘。
Quartz 2D

本次小Demo分2块,一个是自己写的小黄人的头部实战使用.确实很挫..里面主要是一些圆,弧,线,的使用.

第二个是找到的关于基础使用比较全的一个Demo.

11111QQ20150714-1@2x

代码1.小黄人:

- (void)drawRect:(CGRect)rect
{
    // 1.获取上下文
    CGContextRef ctx = UIGraphicsGetCurrentContext();

// 2.身体
drawBody(ctx, rect);

// 3.嘴
drawZui(ctx, rect);

// 3.画眼睛
drawEyes(ctx, rect);

}

/**

  • 眼睛
    /
    void drawEyes(CGContextRef ctx, CGRect rect)
    {
    // 0.其他变量
    CGFloat kuangXPading = 5;
    CGFloat eyesBianKuangHight = 15; // 眼睛边框的高度
    // 1.黑色绑带
    CGFloat startX = rect.size.width     0.5 - BMRadius;
    CGFloat startY = BMTopY;
    CGContextMoveToPoint(ctx, startX, startY);
    CGFloat endX = startX + 2 * BMRadius;
    CGFloat endY = startY;
    CGContextAddLineToPoint(ctx, endX, endY);
    CGContextSetLineWidth(ctx, 30); // 绑带线条
    [[UIColor blackColor] set];
    // 绘制线条
    CGContextStrokePath(ctx);

    //画眼镜框边框(左)
    CGFloat EyesBianKuangRadius = BMRadius 0.96;
    CGFloat EyesBianKuangX = rect.size.width     0.5 - EyesBianKuangRadius + kuangXPading;
    CGFloat EyesBianKuangY = BMTopY - eyesBianKuangHight ;
    CGContextMoveToPoint(ctx, EyesBianKuangX, EyesBianKuangY);
    CGFloat endEyesBianKuangX = EyesBianKuangX;
    CGFloat endEyesBianKuangY = BMTopY + eyesBianKuangHight;
    CGContextAddLineToPoint(ctx, endEyesBianKuangX, endEyesBianKuangY);
    CGContextSetLineWidth(ctx, 10); // 绑带线条
    CGContextSetLineCap(ctx, kCGLineCapRound);
    [BMColor(142, 142, 142) set];
    CGContextStrokePath(ctx);

    // 2.最外圈的镜框
    [BMColor(92, 92, 92) set];
    CGFloat kuangRadius = EyesBianKuangRadius 0.5;
    CGFloat kuangY = startY;
    CGFloat kuangX = rect.size.width     0.5 - kuangRadius + kuangXPading;
    CGContextAddArc(ctx, kuangX, kuangY, kuangRadius, 0, M_PI * 2, 0);
    CGContextFillPath(ctx);

    // 3.里面的皮肤框
    [BMColor(252, 198, 0) set];
    CGFloat yellowRadius = kuangRadius * 0.76;
    CGFloat yellowX = kuangX;
    CGFloat yellowY = kuangY;

    CGContextAddArc(ctx, yellowX, yellowY, yellowRadius, 0, M_PI * 2, 0);
    CGContextFillPath(ctx);

    // 3.2里面的白框
    [[UIColor whiteColor] set];
    CGFloat whiteRadius = yellowRadius 0.9; // 眼睛大小
    CGFloat whiteX = kuangX;
    CGFloat whiteY = kuangY;
    CGContextAddArc(ctx, whiteX, whiteY, whiteRadius, 0, M_PI     2 , 0);

    CGContextFillPath(ctx);

    // 4.在里面的眼框
    [BMColor(108, 81, 55) set];
    CGFloat eyeRadius = whiteRadius 0.48;
    CGFloat eyeX = kuangX ;
    CGFloat eyeY = kuangY + 5; // 眼眶下移.
    CGContextAddArc(ctx, eyeX, eyeY, eyeRadius, 0, M_PI     2, 0);
    CGContextFillPath(ctx);

    // 4.1在里面的眼珠
    [[UIColor blackColor] set];
    CGFloat eyeZhuRadius = eyeRadius 0.55;
    CGFloat eyeZHuX = eyeX;
    CGFloat eyeZHUY = eyeY + 5; // 眼珠下移.
    CGContextAddArc(ctx, eyeZHuX, eyeZHUY, eyeZhuRadius, 0, M_PI     2, 0);
    CGContextFillPath(ctx);

    //4.2 眼白
    [[UIColor whiteColor] set];
    CGFloat eyeBaiRadius = eyeZhuRadius 0.2;
    CGFloat eyeBaiX = eyeZHuX + 6; // 眼白位置控制.
    CGFloat eyeBaiY = eyeZHUY + 0; // 眼白位置控制.
    CGContextAddArc(ctx, eyeBaiX, eyeBaiY, eyeBaiRadius, 0, M_PI     2, 0);
    CGContextFillPath(ctx);

    //眼皮
    [BMColor(252, 198, 0) set];
    CGFloat eyePiRadius = whiteRadius;
    CGFloat eyePiX = kuangX;
    CGFloat eyePiY = kuangY;
    CGContextMoveToPoint(ctx, eyePiX - eyePiRadius, eyePiY);
    CGFloat contrilEyePiX = eyePiX;
    CGFloat contrilEyePiY = eyePiY + 10; // 眼皮大小
    CGContextAddQuadCurveToPoint(ctx, contrilEyePiX, contrilEyePiY, eyePiX + eyePiRadius, eyePiY);
    CGContextAddArc(ctx, eyePiX, eyePiY, eyePiRadius, 0, M_PI , 1);
    CGContextFillPath(ctx);

    //另一侧眼镜框边框(右)

    CGFloat otherEyesBianKuangX = rect.size.width * 0.5 + EyesBianKuangRadius - kuangXPading;
    CGFloat otherEyesBianKuangY = BMTopY - eyesBianKuangHight ;
    CGContextMoveToPoint(ctx, otherEyesBianKuangX, otherEyesBianKuangY);
    CGFloat otherendEyesBianKuangX = otherEyesBianKuangX;
    CGFloat otherendEyesBianKuangY = BMTopY + eyesBianKuangHight;
    CGContextAddLineToPoint(ctx, otherendEyesBianKuangX, otherendEyesBianKuangY);
    CGContextSetLineWidth(ctx, 10); // 绑带线条
    CGContextSetLineCap(ctx, kCGLineCapRound);
    [BMColor(142, 142, 142) set];
    CGContextStrokePath(ctx);

    // 5.另外一边最外圈的镜框
    [BMColor(92, 92, 92) set];
    CGFloat OtherKuangY = kuangY;
    CGFloat OtherKuangX = rect.size.width 0.5 + kuangRadius - kuangXPading;
    CGContextAddArc(ctx, OtherKuangX, OtherKuangY, kuangRadius, 0, M_PI     2, 0);
    CGContextFillPath(ctx);

    // 6.另外一侧里面的皮肤框
    [BMColor(252, 198, 0) set];
    CGFloat otheryellowX = OtherKuangX;
    CGFloat otheryellowY = OtherKuangY;
    CGContextAddArc(ctx, otheryellowX, otheryellowY, yellowRadius, 0, M_PI * 2, 0);
    CGContextFillPath(ctx);

    // 6.2里面的白框
    [[UIColor whiteColor] set];
    CGFloat otherwhiteX = OtherKuangX;
    CGFloat otherwhiteY = OtherKuangY;
    CGContextAddArc(ctx, otherwhiteX, otherwhiteY, whiteRadius, 0, M_PI * 2, 0);
    CGContextFillPath(ctx);

    // 7.在里面的眼框
    [BMColor(108, 81, 55) set];
    CGFloat otherEyeX = OtherKuangX ;
    CGFloat otherEyeY = OtherKuangY + 5; // 眼眶下移
    CGContextAddArc(ctx, otherEyeX, otherEyeY, eyeRadius, 0, M_PI 2, 0);
    CGContextFillPath(ctx);
    // 7.2在里面的眼珠
    [[UIColor blackColor] set];
    CGFloat othereyeZHuX = otherEyeX;
    CGFloat othereyeZHUY = otherEyeY + 5; // 眼珠下移.
    CGContextAddArc(ctx, othereyeZHuX, othereyeZHUY, eyeZhuRadius, 0, M_PI     2, 0);
    CGContextFillPath(ctx);

    //7.3 眼白
    [[UIColor whiteColor] set];
    CGFloat othereyeBaiX = othereyeZHuX - 4;
    CGFloat othereyeBaiY = othereyeZHUY + 0; // 眼白控制.
    CGContextAddArc(ctx, othereyeBaiX, othereyeBaiY, eyeBaiRadius, 0, M_PI * 2, 0);
    CGContextFillPath(ctx);

    //另一边眼皮
    [BMColor(252, 198, 0) set];
    CGFloat otherEyePiRadius = whiteRadius;
    CGFloat otherEyePiX = OtherKuangX;
    CGFloat otherEyePiY = OtherKuangY;
    CGContextMoveToPoint(ctx, otherEyePiX - otherEyePiRadius, otherEyePiY);
    CGFloat controlOtherEyePiX = otherEyePiX;
    CGFloat controlOtherEyePiY = otherEyePiY + 10; // 眼皮大小
    CGContextAddQuadCurveToPoint(ctx, controlOtherEyePiX, controlOtherEyePiY, otherEyePiX + otherEyePiRadius, otherEyePiY);
    CGContextAddArc(ctx, otherEyePiX, otherEyePiY, otherEyePiRadius, 0, M_PI , 1);
    CGContextFillPath(ctx);

}

/**

  • 画眼镜框边框
    */
    void drawEyesBianKuang(CGContextRef ctx, CGRect rect)
    {
    CGFloat eyesBianKuangHight = 20; // 眼睛边框的高度

    // 左
    CGFloat startX = rect.size.width 0.5 - BMRadius 0.48;
    CGFloat startY = BMTopY - eyesBianKuangHight - 5;
    CGContextMoveToPoint(ctx, startX, startY);
    CGFloat endX = startX;
    CGFloat endY = BMTopY + eyesBianKuangHight;
    CGContextAddLineToPoint(ctx, endX, endY);
    CGContextSetLineWidth(ctx, 10); // 绑带线条
    CGContextSetLineCap(ctx, kCGLineCapRound);
    [BMColor(234, 234, 234) set];
    // 绘制线条
    CGContextStrokePath(ctx);

    // 右

}
/**

  • 画嘴
    /
    void drawZui(CGContextRef ctx, CGRect rect)
    {
    // 中间的控制点
    CGFloat controlX = rect.size.width     0.5;
    CGFloat controlY = rect.size.height * 0.4;

    // 当前点
    CGFloat marginX = 40;
    CGFloat marginY = - 18;
    CGFloat currentX = controlX - marginX;
    CGFloat currentY = controlY - marginY;
    CGContextMoveToPoint(ctx, currentX, currentY);

    // 结束点
    CGFloat endX = controlX + marginX;
    CGFloat endY = currentY;

    // 贝塞尔曲线
    CGContextAddQuadCurveToPoint(ctx, controlX, controlY, endX, endY);

    // 设置颜色
    [[UIColor blackColor] set];

    // 渲染
    CGContextStrokePath(ctx);
    }

/**

  • 画身体
    /
    void drawBody(CGContextRef ctx, CGRect rect)
    {
    // 上半圆
    CGFloat topX = rect.size.width     0.5;
    CGFloat topY = BMTopY;
    CGFloat topRadius = BMRadius;
    CGContextAddArc(ctx, topX, topY, topRadius, 0, M_PI, 1);

    // 向下延伸
    CGFloat middleX = topX - topRadius;
    CGFloat middleH = 200; // 中间身体的高度
    CGFloat middleY = topY + middleH;
    CGContextAddLineToPoint(ctx, middleX, middleY);

    // 下半圆
    CGFloat bottomX = topX;
    CGFloat bottomY = middleY;
    CGFloat bottomRadius = topRadius;
    CGContextAddArc(ctx, bottomX, bottomY, bottomRadius, M_PI, 0, 1);

    // 合并路径
    CGContextClosePath(ctx);

    // 设置颜色
    [BMColor(252, 218, 0) set];

    // 利用填充方式画出之前的路径
    CGContextFillPath(ctx);
    }

     

代码2.转载示例代码:

#define PI M_PI

#import “allView.h”

#import <QuartzCore/QuartzCore.h>
@implementation allView

  • (void)drawRect:(CGRect)rect {
    //An opaque type that represents a Quartz 2D drawing environment.
    //一个不透明类型的Quartz 2D绘画环境,相当于一个画布,你可以在上面任意绘画
    CGContextRef context = UIGraphicsGetCurrentContext();

    /写文字/
    [@”画圆：” drawInRect:CGRectMake(10, 20, 80, 20) withAttributes:nil];
    [@”画线及孤线：” drawInRect:CGRectMake(10, 80, 100, 20) withAttributes:nil];;
    [@”画矩形：” drawInRect:CGRectMake(10, 120, 80, 20) withAttributes:nil];;
    [@”画扇形和椭圆：” drawInRect:CGRectMake(10, 160, 110, 20) withAttributes:nil];;
    [@”画三角形：” drawInRect:CGRectMake(10, 220, 80, 20) withAttributes:nil];;
    [@”画圆角矩形：” drawInRect:CGRectMake(10, 260, 100, 20) withAttributes:nil];;
    [@”画贝塞尔曲线：” drawInRect:CGRectMake(10, 300, 100, 20) withAttributes:nil];;
    [@”图片：” drawInRect:CGRectMake(10, 340, 80, 20) withAttributes:nil];

    /画圆/
    //边框圆
    CGContextSetRGBStrokeColor(context,1,1,1,1.0);//画笔线的颜色
    CGContextSetLineWidth(context, 1.0);//线的宽度
    //void CGContextAddArc(CGContextRef c,CGFloat x, CGFloat y,CGFloat radius,CGFloat startAngle,CGFloat endAngle, int clockwise)1弧度＝180°/π （≈57.3°） 度＝弧度×180°/π 360°＝360×π/180 ＝2π 弧度
    // x,y为圆点坐标，radius半径，startAngle为开始的弧度，endAngle为 结束的弧度，clockwise 0为顺时针，1为逆时针。
    CGContextAddArc(context, 100, 20, 15, 0, 2*PI , 0); //添加一个圆
    CGContextDrawPath(context, kCGPathStroke); //绘制路径

    //填充圆，无边框
    CGContextAddArc(context, 150, 30, 30, 0, 2*PI, 0); //添加一个圆
    CGContextDrawPath(context, kCGPathFill);//绘制填充

    //画大圆并填充颜
    UIColoraColor = [UIColor colorWithRed:1 green:0.0 blue:0 alpha:1];
    CGContextSetFillColorWithColor(context, aColor.CGColor);//填充颜色
    CGContextSetLineWidth(context, 3.0);//线的宽度
    CGContextAddArc(context, 250, 40, 40, 0, 2    PI, 0); //添加一个圆
    //kCGPathFill填充非零绕数规则,kCGPathEOFill表示用奇偶规则,kCGPathStroke路径,kCGPathFillStroke路径填充,kCGPathEOFillStroke表示描线，不是填充
    CGContextDrawPath(context, kCGPathFillStroke); //绘制路径加填充

    /画线及孤线/
    //画线
    CGPoint aPoints[2];//坐标点
    aPoints[0] =CGPointMake(100, 80);//坐标1
    aPoints[1] =CGPointMake(130, 80);//坐标2
    //CGContextAddLines(CGContextRef c, const CGPoint points[],size_t count)
    //points[]坐标数组，和count大小
    CGContextAddLines(context, aPoints, 2);//添加线
    CGContextDrawPath(context, kCGPathStroke); //根据坐标绘制路径

    //画笑脸弧线
    //左
    CGContextSetRGBStrokeColor(context, 0, 0, 1, 1);//改变画笔颜色
    CGContextMoveToPoint(context, 140, 80);//开始坐标p1
    //CGContextAddArcToPoint(CGContextRef c, CGFloat x1, CGFloat y1,CGFloat x2, CGFloat y2, CGFloat radius)
    //x1,y1跟p1形成一条线的坐标p2，x2,y2结束坐标跟p3形成一条线的p3,radius半径,注意, 需要算好半径的长度,
    CGContextAddArcToPoint(context, 148, 68, 156, 80, 10);
    CGContextStrokePath(context);//绘画路径

    //右
    CGContextMoveToPoint(context, 160, 80);//开始坐标p1
    //CGContextAddArcToPoint(CGContextRef c, CGFloat x1, CGFloat y1,CGFloat x2, CGFloat y2, CGFloat radius)
    //x1,y1跟p1形成一条线的坐标p2，x2,y2结束坐标跟p3形成一条线的p3,radius半径,注意, 需要算好半径的长度,
    CGContextAddArcToPoint(context, 168, 68, 176, 80, 10);
    CGContextStrokePath(context);//绘画路径

    //右
    CGContextMoveToPoint(context, 150, 90);//开始坐标p1
    //CGContextAddArcToPoint(CGContextRef c, CGFloat x1, CGFloat y1,CGFloat x2, CGFloat y2, CGFloat radius)
    //x1,y1跟p1形成一条线的坐标p2，x2,y2结束坐标跟p3形成一条线的p3,radius半径,注意, 需要算好半径的长度,
    CGContextAddArcToPoint(context, 158, 102, 166, 90, 10);
    CGContextStrokePath(context);//绘画路径
    //注，如果还是没弄明白怎么回事，请参考：http://donbe.blog.163.com/blog/static/138048021201052093633776/

    /画矩形/
    CGContextStrokeRect(context,CGRectMake(100, 120, 10, 10));//画方框
    CGContextFillRect(context,CGRectMake(120, 120, 10, 10));//填充框
    //矩形，并填弃颜色
    CGContextSetLineWidth(context, 2.0);//线的宽度
    aColor = [UIColor blueColor];//blue蓝色
    CGContextSetFillColorWithColor(context, aColor.CGColor);//填充颜色
    aColor = [UIColor yellowColor];
    CGContextSetStrokeColorWithColor(context, aColor.CGColor);//线框颜色
    CGContextAddRect(context,CGRectMake(140, 120, 60, 30));//画方框
    CGContextDrawPath(context, kCGPathFillStroke);//绘画路径

    //矩形，并填弃渐变颜色
    //关于颜色参考http://blog.sina.com.cn/s/blog_6ec3c9ce01015v3c.html
    //http://blog.csdn.net/reylen/article/details/8622932
    //第一种填充方式，第一种方式必须导入类库quartcore并#import <QuartzCore/QuartzCore.h>，这个就不属于在context上画，而是将层插入到view层上面。那么这里就设计到Quartz Core 图层编程了。
    CAGradientLayer *gradient1 = [CAGradientLayer layer];
    gradient1.frame = CGRectMake(240, 120, 60, 30);
    gradient1.colors = [NSArray arrayWithObjects:(id)[UIColor whiteColor].CGColor,

    (id)[UIColor grayColor].CGColor,
(id)[UIColor blackColor].CGColor,
(id)[UIColor yellowColor].CGColor,
(id)[UIColor blueColor].CGColor,
(id)[UIColor redColor].CGColor,
(id)[UIColor greenColor].CGColor,
(id)[UIColor orangeColor].CGColor,
(id)[UIColor brownColor].CGColor,nil];

    [self.layer insertSublayer:gradient1 atIndex:0];
    //第二种填充方式
    CGColorSpaceRef rgb = CGColorSpaceCreateDeviceRGB();
    CGFloat colors[] =
    {

    1,1,1, 1.00,
1,1,0, 1.00,
1,0,0, 1.00,
1,0,1, 1.00,
0,1,1, 1.00,
0,1,0, 1.00,
0,0,1, 1.00,
0,0,0, 1.00,

    };
    CGGradientRef gradient = CGGradientCreateWithColorComponents
    (rgb, colors, NULL, sizeof(colors)/(sizeof(colors[0])4));//形成梯形，渐变的效果
    CGColorSpaceRelease(rgb);
    //画线形成一个矩形
    //CGContextSaveGState与CGContextRestoreGState的作用
    /
    CGContextSaveGState函数的作用是将当前图形状态推入堆栈。之后，您对图形状态所做的修改会影响随后的描画操作，但不影响存储在堆栈中的拷贝。在修改完成后，您可以通过CGContextRestoreGState函数把堆栈顶部的状态弹出，返回到之前的图形状态。这种推入和弹出的方式是回到之前图形状态的快速方法，避免逐个撤消所有的状态修改；这也是将某些状态（比如裁剪路径）恢复到原有设置的唯一方式。
    */
    CGContextSaveGState(context);
    CGContextMoveToPoint(context, 220, 90);
    CGContextAddLineToPoint(context, 240, 90);
    CGContextAddLineToPoint(context, 240, 110);
    CGContextAddLineToPoint(context, 220, 110);
    CGContextClip(context);//context裁剪路径,后续操作的路径
    //CGContextDrawLinearGradient(CGContextRef context,CGGradientRef gradient, CGPoint startPoint, CGPoint endPoint,CGGradientDrawingOptions options)
    //gradient渐变颜色,startPoint开始渐变的起始位置,endPoint结束坐标,options开始坐标之前or开始之后开始渐变
    CGContextDrawLinearGradient(context, gradient,CGPointMake

    (220,90) ,CGPointMake(240,110),
kCGGradientDrawsAfterEndLocation);

    CGContextRestoreGState(context);// 恢复到之前的context

    //再写一个看看效果
    CGContextSaveGState(context);
    CGContextMoveToPoint(context, 260, 90);
    CGContextAddLineToPoint(context, 280, 90);
    CGContextAddLineToPoint(context, 280, 100);
    CGContextAddLineToPoint(context, 260, 100);
    CGContextClip(context);//裁剪路径
    //说白了，开始坐标和结束坐标是控制渐变的方向和形状
    CGContextDrawLinearGradient(context, gradient,CGPointMake

    (260, 90) ,CGPointMake(260, 100),
kCGGradientDrawsAfterEndLocation);

    CGContextRestoreGState(context);// 恢复到之前的context

    //下面再看一个颜色渐变的圆
    CGContextDrawRadialGradient(context, gradient, CGPointMake(300, 100), 0.0, CGPointMake(300, 100), 10, kCGGradientDrawsBeforeStartLocation);

    /画扇形和椭圆/
    //画扇形，也就画圆，只不过是设置角度的大小，形成一个扇形
    aColor = [UIColor colorWithRed:0 green:1 blue:1 alpha:1];
    CGContextSetFillColorWithColor(context, aColor.CGColor);//填充颜色
    //以10为半径围绕圆心画指定角度扇形
    CGContextMoveToPoint(context, 160, 180);
    CGContextAddArc(context, 160, 180, 30, -60 PI / 180, -120 PI / 180, 1);
    CGContextClosePath(context);
    CGContextDrawPath(context, kCGPathFillStroke); //绘制路径

    //画椭圆
    CGContextAddEllipseInRect(context, CGRectMake(160, 180, 20, 8)); //椭圆
    CGContextDrawPath(context, kCGPathFillStroke);

    /画三角形/
    //只要三个点就行跟画一条线方式一样，把三点连接起来
    CGPoint sPoints[3];//坐标点
    sPoints[0] =CGPointMake(100, 220);//坐标1
    sPoints[1] =CGPointMake(130, 220);//坐标2
    sPoints[2] =CGPointMake(130, 160);//坐标3
    CGContextAddLines(context, sPoints, 3);//添加线
    CGContextClosePath(context);//封起来
    CGContextDrawPath(context, kCGPathFillStroke); //根据坐标绘制路径

    /画圆角矩形/
    float fw = 180;
    float fh = 280;

    CGContextMoveToPoint(context, fw, fh-20); // 开始坐标右边开始
    CGContextAddArcToPoint(context, fw, fh, fw-20, fh, 10); // 右下角角度
    CGContextAddArcToPoint(context, 120, fh, 120, fh-20, 10); // 左下角角度
    CGContextAddArcToPoint(context, 120, 250, fw-20, 250, 10); // 左上角
    CGContextAddArcToPoint(context, fw, 250, fw, fh-20, 10); // 右上角
    CGContextClosePath(context);
    CGContextDrawPath(context, kCGPathFillStroke); //根据坐标绘制路径

    /画贝塞尔曲线/
    //二次曲线
    CGContextMoveToPoint(context, 120, 300);//设置Path的起点
    CGContextAddQuadCurveToPoint(context,190, 310, 120, 390);//设置贝塞尔曲线的控制点坐标和终点坐标
    CGContextStrokePath(context);
    //三次曲线函数
    CGContextMoveToPoint(context, 200, 300);//设置Path的起点
    CGContextAddCurveToPoint(context,250, 280, 250, 400, 280, 300);//设置贝塞尔曲线的控制点坐标和控制点坐标终点坐标
    CGContextStrokePath(context);

    /图片/
    UIImage *image = [UIImage imageNamed:@”IMG_0291”];
    [image drawInRect:CGRectMake(60, 340, 50, 50)];//在坐标中画出图片
    // [image drawAtPoint:CGPointMake(100, 340)];//保持图片大小在point点开始画图片，可以把注释去掉看看
    CGContextDrawImage(context, CGRectMake(60, 400, 50, 50), image.CGImage);//使用这个使图片上下颠倒了，参考http://blog.csdn.net/koupoo/article/details/8670024

    // CGContextDrawTiledImage(context, CGRectMake(0, 0, 20, 20), image.CGImage);//平铺图
    }
    原文出处:http://blog.csdn.net/rhljiayou/article/details/9919713