Question

跪求！！ Vc 实现画直线的功能？

学的是计算机图形学，老师留了道作业题，用所学的DDA算法实现画直线的功能。仅能使用画点函数
Windows API:setpixel(hdc, x, y, color);

我现在还不知道应该怎样实现接口。

请大家帮帮忙，给个源代码（能运行的）；
能不能给个能编译通过的代码？谢谢了

Answer 1

bool Bresenham(int x1,int y1,int x2,int y2)
{
/*
int nX1 = x1;
int nY1 = y1;
int nX2 = x2;
int nY2 = y2;

int nDx = abs(nX2 - nX1);
int nDy = abs(nY2 - nY1);
bool bYDirection = false;

if (nDx < nDy)
{
// y direction is step direction
SwapInt(nX1, nY1);
SwapInt(nDx, nDy);
SwapInt(nX2, nY2);
bYDirection = true;
}

// calculate the x, y increment
int nIncreX = (nX2 - nX1) > 0 ? 1 : -1;
int nIncreY = (nY2 - nY1) > 0 ? 1 : -1;

int nCurX = nX1;
int nCurY = nY1;
int nTwoDY = 2 * nDy;
int nTwoDyDx = 2 * (nDy - nDx);
int nIniD = 2 * nDy - nDx;

while (nCurX != nX2) // nCurX == nX2 can not use in bitmap
{
if(nIniD < 0)
{
nIniD += nTwoDY;
// y value keep current state
}
else
{
nCurY += nIncreY;
nIniD += nTwoDyDx;
}
if (bYDirection)
{
//pDC->SetPixel(nCurY, nCurX, RGB(0, 0, 255));
}
else
{
//pDC->SetPixel(nCurX, nCurY, RGB(0, 0, 255));
}
nCurX += nIncreX;
}
*/
return true;
}

Answer 2

用MoveTo函数和LineTo函数绘制直线~