ios - 从手指移动画笔

我想在我的 iPad 应用程序中画画，如下图所示

in my app i have placed a image and while moving the finger(touch movement) i am repeating the images, but my image seems to be as follows.

以下是我绘制图像的代码

            CGBlendMode blendMode = kCGBlendModeColorDodge;
            UIGraphicsBeginImageContext(drawImage.frame.size);
            [drawImage.image drawInRect:CGRectMake(0, 0, drawImage.frame.size.width, drawImage.frame.size.height)];
            CGContextSetLineCap(UIGraphicsGetCurrentContext(), kCGLineCapRound);

////            NSString *imagePath = [[NSBundle mainBundle] pathForResource:@"Watercolor-edge-45x45.png" ofType:nil];
            UIImage * textureColor;// = [UIImage imageWithContentsOfFile:imagePath];
            float angle = hypot(deltaX, deltaY);
            angle *= rand() % 180;//(M_PI / 180);
            CGPoint vector = CGPointMake(currentPoint.x - lastPoint.x, currentPoint.y - lastPoint.y);
            CGFloat distance = hypotf(vector.x, vector.y);
            vector.x /= distance;
            vector.y /= distance;
            for (CGFloat i = 0; i < distance; i += 1.0f) {
                textureColor = [UIImage imageWithCGImage:[self CGImageRotatedByAngle:image angle:angle * -1]];
                CGPoint p = CGPointMake(lastPoint.x + i * vector.x, lastPoint.y + i * vector.y);
                [textureColor drawAtPoint:p blendMode:blendMode alpha:0.1f];
            }
            CGContextBeginPath(UIGraphicsGetCurrentContext());
            CGContextStrokePath(UIGraphicsGetCurrentContext());
            UIImage *newimage = UIGraphicsGetImageFromCurrentImageContext();
            UIGraphicsEndImageContext();

如何获取第一张图片中的我的图片

Actually i have an image and fill the selected color to the image and started drawing here i have a image