3D软引擎之深度排序

花了不少时间去实现了这个功能，大多问题都出现在低级错误，看来以后要提醒十二分精神！错误的原因是：

<span style="color: rgb(255, 255, 255); font-family: Arial; font-size: 14px; line-height: 22px;"> </span>void CTriangle2DUtils::DrawSolidGeneralClipZOrder( D3DXVECTOR3 p0,
	D3DXVECTOR3 p1,
	D3DXVECTOR3 p2, int color )
{

	if (p0.y > p1.y)  Math3D::Swap(p0 , p1);
	if (p0.y > p2.y) Math3D::Swap(p0 , p2);
	if (p1.y > p2.y) Math3D::Swap(p2 , p1);

	if (p0.y > BTM_BORDER_SCR ||
		p2.y < TOP_BORDER_SCR ||
		(p0.x < LEFT_BORDER_SCR && p1.x < LEFT_BORDER_SCR && p2.x < LEFT_BORDER_SCR) ||
		(p0.x > RIGHT_BORDER_SCR && p1.x > RIGHT_BORDER_SCR && p2.x > RIGHT_BORDER_SCR) )
		return;//在可显区域外

	//inv z
	p0.z = 1.0f / p0.z;
	p1.z = 1.0f / p1.z;
	p2.z = 1.0f / p2.z;

	if (FCMP( p0.x , p1.x ) && FCMP( p1.x, p2.x ) ||
		FCMP( p0.y , p1.y ) && FCMP( p1.y, p2.y ) )
	{//绘制退化直线
		DrawDeclineClip(p0 , p1,  p2 , color);
	}
	else if (FCMP( p0.y , p1.y ) )
	{
		CTriangle2DUtils::DrawSolidFlatTopClipZOrder(p0 , p1, p2, color);
	}
	else if ( FCMP( p1.y , p2.y ) )
	{
		CTriangle2DUtils::DrawSolidFlatBottomClipZOrder(p0 , p1, p2, color);
	}
	else
	{
		//had inve z
		float dzdy = (p2.z - p0.z ) / (p2.y - p0.y);
		//float newz = dzdy * (p2.y - p0.y) + p0.z;---------------就这里没有改回来导致了z排序错误
		float newz = dzdy * (p1.y - p0.y) + p0.z;//应该改成这样---------------
		//float newzInv = 1.0f / newz;
		D3DXVECTOR3 pc( LINE_X_NOF(p0.x, p0.y, p2.x, p2.y, p1.y) , p1.y , newz);
		CTriangle2DUtils::DrawSolidFlatBottomClipZOrder(p0 , p1, pc, color);
		CTriangle2DUtils::DrawSolidFlatTopClipZOrder(p1 , pc, p2, color);
	}
}