построить функцию f(x)=|sin(3x)| в win api vusial studio си++. Если правильно, как сделать оси к графику

у меня так получилось................

#include <windows.h>
#include<math.h>
#define COUNT 1000
#define SAVE_AS 101
#define COLOR 201
#define RESET 301
#define ABOUT 401
HINSTANCE hInst;
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
void czCreateMenu(HWND);
void Save_As(HWND);
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR szCmdLine, int iCmdShow)
{
    static LPCWSTR szAppName = L"Graphics";
    HWND hwnd;
    MSG msg;
    WNDCLASSEX wndclass;
    wndclass.cbSize = sizeof(wndclass);
    wndclass.style = CS_HREDRAW | CS_VREDRAW;
    wndclass.lpfnWndProc = WndProc;
    wndclass.cbClsExtra = 0;
    wndclass.cbWndExtra = 0;
    wndclass.hInstance = hInstance;
    wndclass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
    wndclass.hCursor = LoadCursor(NULL, IDC_ARROW);
    wndclass.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
    wndclass.lpszMenuName = NULL;
    wndclass.lpszClassName = szAppName;
    wndclass.hIconSm = LoadIcon(NULL, IDI_APPLICATION);
    RegisterClassEx(&wndclass);
    hwnd = CreateWindow(szAppName, L"Graphics", WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, NULL, NULL, hInstance, NULL);
    ShowWindow(hwnd, iCmdShow);
    UpdateWindow(hwnd);
    SetTimer(hwnd, 1, USER_TIMER_MINIMUM, NULL);
    czCreateMenu(hwnd);
    hInst = hInstance;
    while (GetMessage(&msg, NULL, 0, 0))
    {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }
    return msg.wParam;
}
LRESULT CALLBACK WndProc(HWND hwnd, UINT iMsg, WPARAM wParam, LPARAM lParam)
{
    int wmId;
    static int cxClient, cyClient, Phase = 0;
    HDC hdc;
    PAINTSTRUCT ps;
    CHOOSECOLOR cc;
    static HPEN hPen;
    static COLORREF color = RGB(0, 0, 0), acrCustClr[16];
    unsigned i = 0;
    const static int multiple = 100;
    static POINT pt[COUNT * multiple] = { 0 };
    static bool Move = true;
    switch (iMsg)
    {
    case WM_CREATE:
        for (double x = 0; x < COUNT; x += 0.05)
        {
            double y = 0;
            pt[i].x = (LONG)(x / 5 * multiple);
            double a = abs(sin(3 * x));
            pt[i++].y = (LONG)(a * multiple);
        }
        break;
    case WM_COMMAND:
        wmId = LOWORD(wParam);
        switch (wmId)
        {
        case SAVE_AS:
            Save_As(hwnd);
            break;
        case COLOR:
            cc.lStructSize = sizeof(CHOOSECOLOR);
            cc.hwndOwner = hwnd;
            cc.lpCustColors = (LPDWORD)acrCustClr;
            cc.rgbResult = color;
            cc.Flags = CC_FULLOPEN | CC_RGBINIT;
            ChooseColor(&cc);
            color = cc.rgbResult;
            InvalidateRect(hwnd, NULL, true);
            break;
        case RESET:
            Phase = 0;
            break;
        case ABOUT:
            MessageBox(hwnd, L"GraphicDrawer v.1.0\n© Pashkevich E.A., 2016", L"About", MB_OK | MB_ICONWARNING);
            break;
        }
        break;
    case WM_SIZE:
        cxClient = LOWORD(lParam);
        cyClient = HIWORD(lParam);
        break;
    case WM_PAINT:
        hdc = BeginPaint(hwnd, &ps);
        hPen = CreatePen(0, 1, color);
        SelectObject(hdc, hPen);
        MoveToEx(hdc, pt[0].x, cyClient / 2 - pt[0].y, 0);
        for (unsigned j = Phase; j < cxClient + Phase; j++)
            LineTo(hdc, pt[j].x - Phase, cyClient / 2 - pt[j].y);
        EndPaint(hwnd, &ps);
        break;
    case WM_LBUTTONDOWN:
    case WM_RBUTTONDOWN:
        Move = !Move;
        break;
    case WM_TIMER:
        if (Move){
            Phase++;
            InvalidateRect(hwnd, NULL, true);
        }
        break;
    case WM_DESTROY:
        PostQuitMessage(0);
        break;
    }
    return DefWindowProc(hwnd, iMsg, wParam, lParam);
}
void czCreateMenu(HWND hwnd)
{
    HMENU MainMenu = CreateMenu();
    HMENU mFile = CreatePopupMenu();
    HMENU mView = CreatePopupMenu();
    AppendMenu(MainMenu, MF_STRING | MF_POPUP, (UINT)mFile, L"&File");
    {
        AppendMenu(mFile, MF_STRING, SAVE_AS, L"Save as...");
    }
    AppendMenu(MainMenu, MF_STRING | MF_POPUP, (UINT)mView, L"&View");
    {
        AppendMenu(mView, MF_STRING, COLOR, L"Color");
    }
    AppendMenu(MainMenu, MF_STRING, RESET, L"Reset");
    AppendMenu(MainMenu, MF_STRING, ABOUT, L"About");
    SetMenu(hwnd, MainMenu);
}
void Save_As(HWND hwnd)
{
    OPENFILENAME SaveDialog;
    HANDLE SaveFile;
    DWORD Written;
    HDC hdcMem, hdcWindow;
    HBITMAP hBitmap;
    BYTE *ArrOfImg;
    RECT rt;
    int width = 0, height = 0;
    ZeroMemory(&SaveDialog, sizeof(OPENFILENAME));
    SaveDialog.lStructSize = sizeof(OPENFILENAME);
    SaveDialog.hInstance = hInst;
    SaveDialog.Flags = OFN_OVERWRITEPROMPT;
    SaveDialog.lpstrFilter = L"*.bmp\0*.bmp\0\0";
    SaveDialog.lpstrFile = new TCHAR[100];
    SaveDialog.nMaxFile = _MAX_PATH;
    memset(SaveDialog.lpstrFile, 0, 100);
    GetSaveFileName(&SaveDialog);
    if (!SaveDialog.lpstrFile[0]) return;
    SaveFile = CreateFile(SaveDialog.lpstrFile, GENERIC_WRITE, FILE_SHARE_WRITE, NULL, OPEN_ALWAYS, FILE_ATTRIBUTE_NORMAL, NULL);
    hdcWindow = GetDC(hwnd);
    hdcMem = CreateCompatibleDC(hdcWindow);
    GetClientRect(hwnd, &rt);
    hBitmap = CreateCompatibleBitmap(hdcWindow, width = rt.right - rt.left, height = rt.bottom - rt.top);
    SelectObject(hdcMem, hBitmap);
    BitBlt(hdcMem, 0, 0, width, height, hdcWindow, 0, 0, SRCCOPY);
    BITMAPINFO bmi;
    memset(bmi.bmiColors, 0, sizeof(bmi.bmiColors));
    bmi.bmiHeader.biBitCount = 24;
    bmi.bmiHeader.biClrImportant = 0;
    bmi.bmiHeader.biClrUsed = 0;
    bmi.bmiHeader.biCompression = 0;
    bmi.bmiHeader.biHeight = height;
    bmi.bmiHeader.biWidth = width;
    bmi.bmiHeader.biSizeImage = (width * 3 + width % 4) * height;
    bmi.bmiHeader.biSize = 40;
    bmi.bmiHeader.biPlanes = 1;
    bmi.bmiHeader.biXPelsPerMeter = 0;
    bmi.bmiHeader.biYPelsPerMeter = 0;
    BITMAPFILEHEADER bmfh;
    bmfh.bfType = MAKEWORD('B', 'M');
    bmfh.bfOffBits = sizeof(BITMAPFILEHEADER)+sizeof(BITMAPINFOHEADER);
    bmfh.bfSize = bmfh.bfOffBits + bmi.bmiHeader.biSizeImage;
    bmfh.bfReserved1 = 0;
    bmfh.bfReserved2 = 0;
    WriteFile(SaveFile, &bmfh, sizeof(BITMAPFILEHEADER), &Written, 0);
    WriteFile(SaveFile, &bmi.bmiHeader, sizeof(BITMAPINFOHEADER), &Written, 0);
    ArrOfImg = new BYTE[bmi.bmiHeader.biSizeImage];
    GetDIBits(hdcMem, hBitmap, 0, bmi.bmiHeader.biHeight, ArrOfImg, &bmi, DIB_RGB_COLORS);
    WriteFile(SaveFile, ArrOfImg, bmi.bmiHeader.biSizeImage, &Written, 0);
    CloseHandle(SaveFile);
    delete[] ArrOfImg;
}