C语言实现贪吃蛇之图形界面篇

这已经是贪吃蛇系列的第五篇了，讲真一直写这个也挺无聊的，所以这一篇博文将是系列的最后一篇。虽然已经介绍了贪吃蛇的几种写法，但说到底我们的游戏还只是在一个黑框框里移动的星号。和我们平时玩的贪吃蛇游戏有不少差距。游戏嘛，画面也是很重要的一环。接下来就是让之前的贪吃蛇游戏脱胎换骨的时候了。话不多说，这就开干吧。

　　首先，为了摆脱无趣的黑框（控制台），我们这次新建一个win32项目，直接点击完成。初次接触win32项目的同学可能会感到一股扑面而来的伤害，满屏都是意义不明的字符，这TM还是C语言吗！先不要沮丧，直接运行一下看，看到那优美的窗口，是不是又有了学习的动力。所谓万丈高楼平地起，我们先把原来的代码都给删了。然后复制粘贴上这段简短的代码：

#include <windows.h>

LRESULT CALLBACK WindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam);

int WINAPI wWinMain(HINSTANCE hInstance, HINSTANCE, PWSTR pCmdLine, int nCmdShow)
{
const wchar_t CLASS_NAME[] = L"Game Window Class";

WNDCLASS wc = {};

wc.lpfnWndProc = WindowProc;
wc.hInstance = hInstance;
wc.lpszClassName = CLASS_NAME;

RegisterClass(&wc);

HWND hwnd = CreateWindowEx(
0,
CLASS_NAME,
L"Greedy Snake",
WS_OVERLAPPEDWINDOW,
CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT,
NULL,
NULL,
hInstance,
NULL
);

if (hwnd == NULL)
{
return 0;
}

ShowWindow(hwnd, nCmdShow);

MSG msg = {};
while (GetMessage(&msg, NULL, 0, 0))
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}

return 0;
}

LRESULT CALLBACK WindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
switch (uMsg)
{
case WM_DESTROY:
PostQuitMessage(0);
return 0;

case WM_PAINT:
{
PAINTSTRUCT ps;
HDC hdc = BeginPaint(hwnd, &ps);

FillRect(hdc, &ps.rcPaint, (HBRUSH)(COLOR_WINDOW + 1));

EndPaint(hwnd, &ps);
}
return 0;

}
return DefWindowProc(hwnd, uMsg, wParam, lParam);
}

其实这段代码也是我从MSDN复制过来的，虽然我也很乐意为新手仔细介绍上面一段代码，但解释起来就不是一篇博客的事了。

这里给出MSDN的链接吧：https://msdn.microsoft.com/en-us/library/windows/desktop/ff381409(v=vs.85).aspx

想要入门win32编程的话，这算是非常好的入门教程了，当时我也是看的这个入的门（虽然现在也只是入门水平）。

上面的代码已经能够为我们创造出一个windows窗口了，接下来对这段代码加工一下就能够得到我们最终的贪吃蛇游戏了。

由于贪吃蛇游戏各种功能的实现方法前面已经介绍过了，下面我就直接贴代码了：

#include <windows.h>
#include <time.h>
#include <stdio.h>

#define BEFORE 1
#define PLAYING 2
#define AFTER 3
#define UNIT 20　　//绘图的最小单元

typedef struct node {
COORD cor;
struct node *next;
}node;

COORD food;
node *head;
char len = 1;
COORD snake[100];
FILE *mem;
errno_t err;

int state = BEFORE;
int option = 1;
int old_dir = VK_RIGHT;
int cur_dir = VK_RIGHT;

RECT Client = { 200,100,1000,600 };　　//用户区大小
HBITMAP bg;
HDC hdc, hMemdc;
HFONT hFont;

void draw_options();
void choose(int,HWND);
int no_reverse();
void draw_game(void);
void move_snake();
void init_game();
int cor_cmp(COORD pt1, COORD pt2);
COORD generate_food(void);
int isalive(void);
void save();
void load();
void free_node(node *h);

LRESULT CALLBACK WindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam);

int WINAPI wWinMain(HINSTANCE hInstance, HINSTANCE, PWSTR pCmdLine, int nCmdShow)
{
const wchar_t CLASS_NAME[] = L"Game Window Class";

WNDCLASS wc = {};

wc.lpfnWndProc = WindowProc;
wc.hInstance = hInstance;
wc.lpszClassName = CLASS_NAME;

RegisterClass(&wc);

AdjustWindowRect(&Client, WS_OVERLAPPED, FALSE);　//根据用户区大小生成窗口大小

HWND hwnd = CreateWindowEx(
0,
CLASS_NAME,
L"Greedy Snake",
WS_OVERLAPPEDWINDOW,
Client.left, Client.top, Client.right-Client.left, Client.bottom - Client.top,
NULL,
NULL,
hInstance,
NULL
);

if (hwnd == NULL)
{
return 0;
}

ShowWindow(hwnd, nCmdShow);

MSG msg = {};
while (GetMessage(&msg, NULL, 0, 0))
{
TranslateMessage(&msg);
DispatchMessage(&msg);
}

return 0;
}

LRESULT CALLBACK WindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
switch (uMsg)
{
case WM_CREATE:
hFont = CreateFont(40, 20, 0, 0, FW_BOLD, FALSE, FALSE, FALSE, DEFAULT_CHARSET, OUT_OUTLINE_PRECIS,
CLIP_DEFAULT_PRECIS, CLEARTYPE_QUALITY, VARIABLE_PITCH, TEXT("Impact"));　　//创造字体
return 0;
case WM_DESTROY:
PostQuitMessage(0);
return 0;
case WM_PAINT:
{
PAINTSTRUCT ps;
hdc = BeginPaint(hwnd, &ps);
bg = (HBITMAP)LoadImage(NULL, _T("bg.bmp"), IMAGE_BITMAP, 0, 0, LR_LOADFROMFILE);　　//加载背景图
hMemdc = CreateCompatibleDC(hdc);
SelectObject(hMemdc, bg);
BitBlt(hdc, 0, 0, Client.right, Client.bottom, hMemdc, 0, 0, SRCCOPY);　　//贴背景图
SetBkMode(hdc, TRANSPARENT);　　//使文字透明

if (state == BEFORE)
draw_options();
if (state == PLAYING)
draw_game();

EndPaint(hwnd, &ps);
}
return 0;
case WM_KEYDOWN:
{
if (state == BEFORE)
choose(wParam,hwnd);
if (state == PLAYING) {
if (wParam == VK_ESCAPE) {　　//退出保存
save();
free_node(head);
DestroyWindow(hwnd);
}
if (wParam != VK_RETURN) {　　//这里不判断的话，初始方向会被读为VK_RETURN
old_dir = cur_dir;
cur_dir = wParam;
}
}
}
return 0;
case WM_TIMER:
{
if (wParam == 1) {
move_snake();
InvalidateRect(hwnd, NULL, TRUE);
if (!isalive()) {
free_node(head);
DestroyWindow(hwnd);
}
}
}
return 0;
}
return DefWindowProc(hwnd, uMsg, wParam, lParam);
}

void draw_options()
{
SelectObject(hdc, hFont);
SetTextColor(hdc, RGB(139, 0, 0));
TextOut(hdc, 320, 180, _TEXT("新的游戏"), 4);
TextOut(hdc, 320, 240, _TEXT("继续游戏"), 4);
if (option == 1)
TextOut(hdc, 280, 180, _TEXT("->"), 2);
else
TextOut(hdc, 280, 240, _TEXT("->"), 2);
}

void choose(int key,HWND h)
{
if (key == VK_UP&&option > 1)
option--;
if (key == VK_DOWN&&option < 2)
option++;
if (key == VK_RETURN) {
DeleteObject(hFont);　　//删除创造的字体
state = PLAYING;
if (option == 1)
init_game();
else
load();
SetTimer(h, 1, 100, NULL);
}
InvalidateRect(h, NULL, TRUE);
}

void draw_game(void)
{
node *p = NULL;
SelectObject(hdc, (HBRUSH)GetStockObject(GRAY_BRUSH));
for (p = head; p != NULL; p = p->next)
Rectangle(hdc, (p->cor.X)*UNIT, (p->cor.Y)*UNIT, (p->cor.X + 1)*UNIT, (p->cor.Y + 1)*UNIT);
Ellipse(hdc, food.X*UNIT, food.Y*UNIT, (food.X + 1)*UNIT, (food.Y + 1)*UNIT);
}

void init_game()
{
head = (node *)malloc(sizeof(node));
head->cor.X = 3;
head->cor.Y = 8;
head->next = NULL;
food = { 18,12 };
}

void move_snake()
{
no_reverse();
node *p, *t = NULL;
node *newh = NULL;
newh = (node *)malloc(sizeof(node));
newh->cor = head->cor;
newh->next = head;
head = newh;
int grow = 0;
switch (cur_dir) {
case VK_UP:
head->cor.Y--;
break;
case VK_DOWN:
head->cor.Y++;
break;
case VK_LEFT:
head->cor.X--;
break;
case VK_RIGHT:
head->cor.X++;
break;
}
if (cor_cmp(head->cor, food)) {
grow = 1;
food = generate_food();
}
if (grow) {
len++;
}
else {
for (p = head; p->next->next != NULL; p = p->next)
;
t = p->next;
p->next = NULL;
free(t);
}
}

int no_reverse()
{
int state;
state = cur_dir - old_dir;
if ((state == 2 || state == -2)&&len!=1)
cur_dir = old_dir;
return cur_dir;
}

int cor_cmp(COORD pt1, COORD pt2)
{
return (pt1.X == pt2.X&&pt1.Y == pt2.Y);
}

COORD generate_food(void)
{
COORD food_;
node *p = NULL;
int in_snake = 0;
srand((unsigned int)time(NULL));
do {
food_.X = rand() % 40;
food_.Y = rand() % 25;
for (p = head; p != NULL; p = p->next)
if (cor_cmp(food_, p->cor))
in_snake = 1;
} while (food_.X < 0 || food_.X > 38 || food_.Y < 0 || food_.Y > 22 || in_snake);
return food_;
}

int isalive(void)
{
int self_eat = 0;
node *p = NULL;
for (p = head->next; p != NULL; p = p->next)
if (cor_cmp(p->cor, head->cor))
self_eat = 1;
return (head->cor.X < 0 || head->cor.X > 39 || head->cor.Y < 0 || head->cor.Y > 24 || self_eat) ? 0 : 1;
}
void save()
{
node *p = NULL;
if ((err = fopen_s(&mem, "memory.txt", "w+")) == NULL) {
fwrite(&len, sizeof(len), 1, mem);
fwrite(&cur_dir, sizeof(cur_dir), 1, mem);
fwrite(&food, sizeof(food), 1, mem);
for (p = head; p != NULL; p = p->next)
fwrite(&(p->cor), sizeof(p->cor), 1, mem);
fclose(mem);
}
}
void load()
{
node *p, *q;
int i, j;
if ((err = fopen_s(&mem, "memory.txt", "r")) == NULL) {
fread(&len, sizeof(len), 1, mem);
fread(&cur_dir, sizeof(cur_dir), 1, mem);
fread(&food, sizeof(food), 1, mem);
fread(snake, sizeof(COORD), len, mem);
fclose(mem);
}
p = head = (node *)malloc(sizeof(node));
p->cor = snake[0];
for (i = 1; i < len; i++) {
q = (node *)malloc(sizeof(node));
q->cor = snake[i];
p->next = q;
p = q;
}
p->next = NULL;
}

void free_node(node *h)
{
node *p, *q;
for (p = h; p != NULL; p = q) {
q = p->next;
free(p);
}
}

这样我们便将贪吃蛇游戏图形界面化，上张游戏截图吧：



虽然可以完善的地方还有不少，但是比起刚开始的黑框框星号蛇已经不知道炫到哪里去了。原谅我这个win32贪吃蛇教程讲解不多。因为讲起来确实要讲不少篇幅，有兴趣或者有疑惑的同学可以自行学习windows编程，虽然win32已经算是过时的技术了，但其中的一些思想还是有了解的益处的，而且学会了win32编程，平时做一些小游戏也不愁没有炫酷的界面了