用C語言怎樣寫五角星沿正弦曲線移動,個人基本不會C語言,求高手解答.

#include <Windows.h>

#include <tchar.h>

#include <math.h>

long WINAPI WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam);

UINT SCREEN_WIDTH = 1000;

UINT SCREEN_HEIGHT = 600;

int WINAPI WinMain(HINSTANCE hInstance,

HINSTANCE hPrevInstance,

LPSTR lpCmdLine,

int nCmdShow)

{

TCHAR className[] = _T("serenesunny");

TCHAR windowName[] = _T("五角星");

WNDCLASS wndcls;

wndcls.cbClsExtra = 0;

wndcls.cbWndExtra = 0;

wndcls.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);

wndcls.hCursor = LoadCursor(hInstance, IDC_ARROW);

wndcls.hIcon = LoadIcon(hInstance, IDI_APPLICATION);

wndcls.hInstance = hInstance;

wndcls.lpfnWndProc = WndProc;

wndcls.lpszClassName = className;

wndcls.lpszMenuName = 0;

wndcls.style = CS_HREDRAW | CS_VREDRAW;

RegisterClass(&wndcls);

HWND hWnd = CreateWindow(className, windowName, WS_OVERLAPPEDWINDOW, 0,

0, SCREEN_WIDTH, SCREEN_HEIGHT, 0, 0, hInstance, 0);

ShowWindow(hWnd, SW_SHOWNORMAL);

UpdateWindow(hWnd);

MSG msg;

while (GetMessage(&msg, hWnd, 0, 0))

{

TranslateMessage(&msg);

DispatchMessage(&msg);

}

return msg.wParam;

}

#define Pi 3.1415926

double n = sin(3 * Pi / (double)10) / sin(Pi / (double)10); // 半徑之比

int ti = 0; // 旋轉變量

UINT index = 0;

UINT r[] = { (UINT)(n * 20), 20 };

float theta[] = {(float)(- Pi / 2), (float)(Pi / (float)5 - Pi / 2)};

POINT points[10];

UINT centerx = 100;

UINT centery = SCREEN_HEIGHT / 2;

long WINAPI WndProc(HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam)

{

HDC hdc;

PAINTSTRUCT ps;

HBRUSH hBrush;

// HPEN hPen;

int i;

int index;

switch(message)

{

case WM_CREATE:

case WM_PAINT:

hdc = BeginPaint(hWnd, &ps);

hBrush = CreateSolidBrush(0x00ffff);

SelectObject(hdc, hBrush);

centerx = 100 + ti;

centery = SCREEN_HEIGHT / 2 - (long)(200 * sin(Pi * ti / (double)300));

for (index = 0; index < 5; index++)

{

for (i = 0; i < 2; i++)

{

points[index * 2 + i].x = (long)(centerx + r[i] * cos(theta[i] + index * 2 * Pi / 5));

points[index * 2 + i].y = (long)(centery + r[i] * sin(theta[i] + index * 2 * Pi / 5));

}

}

Polygon(hdc, points, 10); // 把五角星看成壹個10邊形，用多邊形畫法去畫

DeleteObject(hBrush);

ti += 2;

ti = ti % 600;

Sleep(20);

InvalidateRect(hWnd,NULL,1); //重繪窗口區域.

EndPaint(hWnd, &ps);

break;

case WM_CLOSE:

DestroyWindow(hWnd);

break;

case WM_DESTROY:

PostQuitMessage(0);

break;

default:

return DefWindowProc(hWnd, message, wParam, lParam);

}

return 0;

}

如果出現錯誤：

LIBCD.lib(crt0.obj) : error LNK2001: unresolved external symbol _main

解決方法:

控制臺項目要使用windows子系統, 而不是console, 設置:

[Project] --> [Settings] --> 選擇"Link"屬性頁,

在Project Options中將/subsystem:console改成/subsystem:windows.