C++开发绘制正弦曲线的方法
时间：2020-12-09 20:05:53 | 栏目：C代码 | 点击：次
本文实例为大家分享了C++绘制正弦曲线的具体代码，供大家参考，具体内容如下
通过OnDraw函数绘制图形
过程为先绘制两个坐标轴，再绘制正弦曲线的方法。其中将曲线分解为660个像素点，让其看起来更像“曲线”
void CMFCApplication3View::OnDraw(CDC* pDC)
{
CMFCApplication3Doc* pDoc = GetDocument();
ASSERT_VALID(pDoc);
if (!pDoc)
return;
CPen cpen, pen;
pen.CreatePen(PS_DASH, 4, RGB(0, 0, 0)); //建立画笔
cpen.CreatePen(PS_DASH, 2, RGB(0, 0, 255));
pDC->SelectObject(&cpen);
pDC->SetViewportOrg(200, 345); //指定原点
pDC->SetTextColor(RGB(255, 0, 0));
CString sPITEX[] = { "-1/2π","","1/2π","π","3/2π","2π","5/2π","3π","7/2π","4π","9/2π","5π" };
for (int n = -1, nTmp = 0; nTmp < 660; n++, nTmp += 60) {
pDC->LineTo(60 * n, 0);
pDC->LineTo(60 * n, -5);
pDC->MoveTo(60 * n, 0);
pDC->TextOutA(60 * n - sPITEX[n + 1].GetLength() * 3, 16, sPITEX[n + 1]);
}
pDC->MoveTo(0, 0);
CString sTmp;
for (int n = -4, nTmp = 0; nTmp <= 180; n++, nTmp = 60 * n) {
pDC->LineTo(0, 60 * n);
pDC->LineTo(5, 60 * n);
pDC->MoveTo(0, 60 * n);
sTmp.Format("%d", -n);
pDC->TextOutA(10, 60 * n, sTmp);
}
double y, radian;
pDC->SelectObject(&pen);
for (int x = -60; x < 600; x++) {
radian = x / ((double)60 * 2)*3.1415;
y = sin(radian) * 2 * 60;
pDC->MoveTo((int)x, (int)y);
pDC->LineTo((int)x, (int)y);
}
cpen.DeleteObject();
pen.DeleteObject();
// TODO: 在此处为本机数据添加绘制代码
}