Snake-C-drawing program based on easyx graphics library (on): basic control function, easyx

Snake-C-drawing program based on easyx graphics library (on): basic control function, easyx

Since I learned the C language, I have always wanted to make a game. Today I am paying for it. The first time I wrote it, I wrote a lot of bugs. Today, I read several greedy snakes on the Internet and re-wrote them once. The effect is good.

 

The following is a detailed construction process. Due to time constraints, this section first posts an important control function implementation and uses it to create a very simple and interesting drawing program.

 

First, you should have a general understanding of the structure of the Snake. A control system should control the movement of the snake up and down, and cannot move in the opposite direction. There should be a food production system, where the food appears randomly; after eating food, the snake will become longer; there will be a death determination system ......

To sum up, it is like this:

 

 

The structure I wrote is a bit messy, but this is basically the case ~

 

The failure of the first attempt tells me that I want to implement a complete greedy snake. It is difficult for me who haven't touched c for a long time. So this time, I am going to start with a small game that can move squares in the window.

Specifically, there is only a "snake" in the control module.

A snake has four moving directions. We can use vectors to represent it.

Because the screen coordinate system is like this

Therefore, the vector and direction correspond to the following:

Left (-1, 0)

Right (1, 0)

Upper (0,-1)

Lower (0, 1)

 

We use "w a s d" as the control key to obtain the control function:

1 void command () // obtain the Keyboard command 2 {3 if (_ kbhit () // if there is a Keyboard Message 4 switch (_ getch ()) /* getchar () */5 {6 case 'A': 7 array. x =-1; 8 array. y = 0; 9 break; 10 case 'D': 11 array. x = 1; 12 array. y = 0; 13 break; 14 case 'W': 15 array. x = 0; 16 array. y =-1; 17 break; 18 case's ': 19 array. x = 0; 20 array. y = 1; 21 break; 22} 23}

For simplicity, we assume that our snake has only one square and can freely move in four directions.

Then our mobile function can be written as follows:

1 void move () // modify the coordinates of the header node to move 2 {3 snake. x + = array. x * 10; // move 10 pix4 snake each time. y + = array. y * 10; 5 6 setcolor (BLUE); // set the snake color 7 // draw the snake 8 rectangle (snake. x-5, snake. y-5, snake. x + 5, snake. y + 5); 9}

Then write a driver. 

1 # include <graphics. h> 
2 # include <conio. h> 
3 4 typedef struct Position // coordinate structure 5 {6 int x; 7 int y; 8} Pos; 9 10 Pos snake; 11 Pos array; 12 13 int main () 14 {15 snake. x = 300; snake. y = 300; 16 array. x = 1; array. y = 0;
Initgraph (640,480); // initialize the graphical interface 17 while (true) 18 {19 command (); 20 move ();
Sleep (100); 21} 22 return 0; 23}

This small program is like a drawing program, and because there is no boundary judgment, he will keep running somewhere we can't see ~~ The effect is as follows: (garbled ~)

 

The complete code is as follows:

1 # include <graphics. h> 2 # include <conio. h> 3 4 typedef struct Position // coordinate structure 5 {6 int x; 7 int y; 8} Pos; 9 10 Pos snake; 11 Pos array; 12 13 void command () // obtain the Keyboard Command 14 {15 if (_ kbhit () // if there is a Keyboard Message 16 switch (_ getch ()/* getchar () cannot be used here () */17 {18 case 'A': 19 array. x =-1; 20 array. y = 0; 21 break; 22 case 'D': 23 array. x = 1; 24 array. y = 0; 25 break; 26 case 'W': 27 array. x = 0; 28 array. y =-1; 29 break; 30 case's ': 31 array. x = 0; 32 array. y = 1; 33 break; 34} 35} 36 37 void move () // modify the coordinates of the header node to move 38 {39 snake. x + = array. x * 10; // move 10 pix40 snake each time. y + = array. y * 10; 41 42 setcolor (BLUE); // set the snake color 43 // draw the snake 44 rectangle (snake. x-5, snake. y-5, snake. x + 5, snake. y + 5); 45} 46 47 int main () 48 {49 snake. x = 300; snake. y = 300; 50 array. x = 1; array. y = 0; 51 initgraph (640,480); // initialize the graphic interface 52 while (true) 53 {54 command (); 55 move (); 56 Sleep (100 ); 57} 58 return 0; 59}Plotting Program

Well, I feel like I have made a pretty fun sandbox game ~~~

Let's get started with it. Let's get there today.

I have attached my DRDs jellyfish to the end ~~