如何在Android Canvas中使用“倒置”的绘画?
我在画布上画了一些东西,我想画一个倒转的圆圈:
canvas.drawCircle(zx, zy, 8f, myPaint);
  如何配置myPaint使圆像素处于底层像素的反转颜色? 
谢谢
尝试这个
float mx [] = {
             -1.0f,  0.0f,  0.0f,  1.0f,  0.0f,
             0.0f,  -1.0f,  0.0f,  1.0f,  0.0f,
             0.0f,  0.0f,  -1.0f,  1.0f,  0.0f,
             1.0f,  1.0f,  1.0f,  1.0f,  0.0f 
    };
ColorMatrix cm = new ColorMatrix(mx);
p.setColorFilter(new ColorMatrixColorFilter(cm));
canvas.drawCircle(zx, zy, 8f, p);
我会说反转的颜色矩阵应该是这样的:
float mx [] = {
         -1.0f,  0.0f,  0.0f,  0.0f,  255.0f,
         0.0f,  -1.0f,  0.0f,  0.0f,  255.0f,
         0.0f,  0.0f,  -1.0f,  0.0f,  255.0f,
         0.0f,  0.0f,  0.0f,  1.0f,  0.0f 
};
以下是矩阵的更多信息:
myPaint.setColor(Integer.MAX_VALUE - color);
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