C语言中的VGA编程：获取x，y坐标和偏移量

I'm programming the for the 256 color VGA in C. The screen size I have is 320*200 so based on that assumption I made my plot pixel function as follows:

我用C编程为256色VGA。我的屏幕尺寸是320 * 200所以基于这个假设我制作了我的绘图像素功能如下：

void plot_pixel(int x, int y, byte color){
  int offset;
  offset = (y<<8) + (y<<6) + x;
  VGA[offset]=color;
}

I always translate the x, y coordinates of my screen to an offset of video memory. What I'm struggling to achieve is to do the opposite. I would like to send a function the video offset and return to me an array with the 2 integers corresponding to the x and y coordinates:

我总是将屏幕的x，y坐标转换为视频内存的偏移量。我正在努力实现的目标是做相反的事情。我想发送一个函数视频偏移并返回给我一个数组，其中2个整数对应于x和y坐标：

get_xy(int offset){
   ...
}

However, I still cannot find a way to translate a single number into two values.

但是，我仍然找不到将单个数字转换为两个值的方法。

Can anyone help me achieve this?

谁能帮我实现这个目标？

1 个解决方案

#1

Simple reverse the math. Best to use unsigned types.

简单地逆转数学。最好使用无符号类型。

y = offset/((1<<8) + (1<<6)); 
x = offset%((1<<8) + (1<<6));