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#include

#include

const char g_szClassName[] = "Example";

const char g_szCaption[] = "Archimedes\' Screw";

const int ID_TIMER1 = 1,

&nbsp&nbsp&nbsp nScreenWidth = GetSystemMetrics(SM_CXSCREEN),

&nbsp&nbsp&nbsp nScreenHeight = GetSystemMetrics(SM_CYSCREEN);

LRESULT CALLBACK WndProc(HWND hWnd, UINT msg, WPARAM wParam, LPARAM lParam)

{

&nbsp&nbsp&nbsp static bool flag = false;

&nbsp&nbsp&nbsp static double max_theta = 0;

&nbsp&nbsp&nbsp static PAINTSTRUCT ps;

&nbsp&nbsp&nbsp static HDC hDC, mDC;

&nbsp&nbsp&nbsp switch (msg)

&nbsp&nbsp&nbsp {

&nbsp&nbsp&nbsp case WM_PAINT:

&nbsp&nbsp&nbsp &nbsp&nbsp&nbsp hDC = BeginPaint(hWnd, &ps);

&nbsp&nbsp&nbsp &nbsp&nbsp&nbsp for (double theta = 0; theta

&nbsp&nbsp&nbsp &nbsp&nbsp&nbsp &nbsp&nbsp&nbsp SetPixel(hDC, nScreenWidth/2+10*cos(theta)*theta, nScreenHeight/2+10*sin(theta)*theta, RGB(255,0,0));

&nbsp&nbsp&nbsp &nbsp&nbsp&nbsp UpdateWindow(hWnd);

&nbsp&nbsp&nbsp &nbsp&nbsp&nbsp EndPaint(hWnd, &ps);

&nbsp&nbsp&nbsp &nbsp&nbsp&nbsp return 0;

&nbsp&nbsp&nbsp case WM_TIMER:

&nbsp&nbsp&nbsp &nbsp&nbsp&nbsp if (!flag)

&nbsp&nbsp&nbsp &nbsp&nbsp&nbsp {

&nbsp&nbsp&nbsp &nbsp&nbsp&nbsp &nbsp&nbsp&nbsp if (max_theta

&nbsp&nbsp&nbsp &nbsp&nbsp&nbsp &nbsp&nbsp&nbsp {

&nbsp&nbsp&nbsp &nbsp&nbsp&nbsp &nbsp&nbsp&nbsp &nbsp&nbsp&nbsp max_theta += 5;

&nbsp&nbsp&nbsp &nbsp&nbsp&nbsp &nbsp&nbsp&nbsp &nbsp&nbsp&nbsp InvalidateRect(hWnd, NULL, TRUE);

&nbsp&nbsp&nbsp &nbsp&nbsp&nbsp &nbsp&nbsp&nbsp }

&nbsp&nbsp&nbsp &nbsp&nbsp&nbsp &nbsp&nbsp&nbsp else flag = true;

&nbsp&nbsp&nbsp &nbsp&nbsp&nbsp }

&nbsp&nbsp&nbsp &nbsp&nbsp&nbsp else if (max_theta > 0)

&nbsp&nbsp&nbsp &nbsp&nbsp&nbsp {

&nbsp&nbsp&nbsp &nbsp&nbsp&nbsp &nbsp&nbsp&nbsp max_theta -= 5;

&nbsp&nbsp&nbsp &nbsp&nbsp&nbsp &nbsp&nbsp&nbsp InvalidateRect(hWnd, NULL, TRUE);

&nbsp&nbsp&nbsp &nbsp&nbsp&nbsp }

&nbsp&nbsp&nbsp &nbsp&nbsp&nbsp else KillTimer(hWnd, ID_TIMER1);

&nbsp&nbsp&nbsp &nbsp&nbsp&nbsp return 0;

&nbsp&nbsp&nbsp case WM_DESTROY:

&nbsp&nbsp&nbsp &nbsp&nbsp&nbsp PostQuitMessage(0);

&nbsp&nbsp&nbsp &nbsp&nbsp&nbsp return 0;

&nbsp&nbsp&nbsp }

&nbsp&nbsp&nbsp return DefWindowProcA(hWnd, msg, wParam, lParam);

}

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow)

{

&nbsp&nbsp&nbsp WNDCLASSA wc;

&nbsp&nbsp&nbsp HWND hWnd;

&nbsp&nbsp&nbsp MSG msg;

&nbsp&nbsp&nbsp wc.style&nbsp &nbsp &nbsp &nbsp  = 0;