醉Mandelbrot实现

Question

我写了一个应该绘制Mandelbrot分形的程序。不幸的是，它似乎醉了。下面是输出：

相关功能：

void drawMandelbrot(float x, float y, float width, float height, float delta) { 
    for (float currentX = -2; currentX < 2; currentX += delta) { 
     for (float currentY = -2; currentY < 2; currentY += delta) { 
      Complex z(0, 0); 
      Complex c(currentX, currentY); 
      int iterations = 0; 

      do { 
       z = z * z + c; 
       ++iterations; 
      } 
      while (z.getAbsoluteValue() <= 2 && iterations < MANDELBROT_ITERATION_LIMIT); 

      ALLEGRO_COLOR pixelColor; 
      float pixelX = (currentX + 2)/4 * width; 
      float pixelY = (currentY + 2)/4 * width; 

      if (z.getAbsoluteValue() <= 2) { 
       pixelColor = blackColor; 
       // Commented because you might not want this much junk in your terminal 
       //std::cout << "Stayed small! " << z.toString() << std::endl; 
      } else { 
       pixelColor = al_color_hsv(iterations/MANDELBROT_ITERATION_LIMIT, 1.0f, 1.0f); 
       // idem 
       //std::cout << "Blew up! " << z.toString() << std::endl; 
      } 
      al_draw_pixel(pixelX, pixelY, pixelColor); 
     } 
    } 
} 

我相信Complex::operator...方法是正确的，我在上面的功能怀疑一个逻辑错误。当检查上面（注释过的）std :: cout语句的输出时，输出中复数的绝对值确实小于2，但图像看起来不像绘制的mandelbrot集。

错在何处？

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编辑历史中包含mcve。

Answer 1

您对复数模量的计算不正确。

float Complex::getAbsoluteValue() const { 
    return sqrt(real * real + imaginary + imaginary); 
} 

你，因为你删除后的这一部分，但它应该说

float Complex::getAbsoluteValue() const { 
    return sqrt(real * real + imaginary * imaginary); 
}