Genius usage of C macro

Let's see how foreigners use macros. This example is taken from expert C programming. A small bitwise pattern is used to map an icon or graph (glyph) to an image generated on the screen. One digit represents a pixel in the image. If a single bit is set, the pixel it represents is "bright. If a single bit is cleared, the pixels it represents are "dark. Therefore, a series of integer values can be used for image encoding. Tools like iconedit are used for plotting. They output an ASCII file containing a series of integer numbers, which can be used by a window. Program . The problem is that the icon in the program is only a string of hexadecimal numbers. In C, a typical 16x16 black/white image may be as follows: static unsigned short stopwatch [] = {
0x07c6,
0x1ff7,
0x383b,
0x600c,
0x600c,
0xc006,
0xc006,
0xdf06,
0xc106,
0xc106,
0x610c,
0x610c,
0x3838,
0x1ff0,
0x07c0,
Zero x 0000
};

As we can see, these C-language constants do not provide any clue about the actual image. Here is an amazing # define-defined elegant set that allows programs to create constants to make them look like images on the screen. # Define x) * 2 + 1
# DEFINE _) * 2
# Define s (0/* for building glyphs 16 bits wide */

After they are defined, the program will automatically create their hexadecimal mode as long as they draw the required icons or graphics. Using these macro definitions, the self-describing capability of the program is greatly enhanced. The above example can be changed to: static unsigned short stopwatch [] =
{
S _ x _,
S _ x,
S _ x,
S _ x __,
S _ x __,
S x _,
S x _,
S x _,
S x _,
S x _,
S _ x __,
S _ x __,
S _ x ___,
S _ x ____,
S _ x ______,
S ________________
};

ObviouslyCodeIn contrast, it means more obvious. The standard C language has octal, decimal, and hexadecimal constants, but there is no binary constant. Otherwise, it is a simpler method for drawing the image mode.

If you capture the top-right corner of the book and see this page oblique, you may guess that this is a small stopwatch image named "cursor busy" for the popular window system. I learned this technique from Usenet Comp. Lang. C News group a few years ago.

Do not forget to clear these macro definitions after the drawing is complete. Otherwise, this may cause unpredictable consequences for your subsequent code.