DX9,遇到一个棘手的蒙版问题

pandahur 2012-04-09 09:42:14

如果一个场景有好几面镜子，都用蒙板来渲染，那么如何防止镜子a的StencilFail像素绘制到了镜子b上面？



HRESULT hr;



	pd3dDevice->SetRenderState(D3DRS_STENCILENABLE,	TRUE);

	pd3dDevice->SetRenderState(D3DRS_STENCILFUNC, D3DCMP_ALWAYS);

	pd3dDevice->SetRenderState(D3DRS_STENCILREF, 0x1);

	pd3dDevice->SetRenderState(D3DRS_STENCILMASK, 0xffffffff);

	pd3dDevice->SetRenderState(D3DRS_STENCILWRITEMASK, 0xffffffff);

	pd3dDevice->SetRenderState(D3DRS_STENCILZFAIL, 	D3DSTENCILOP_KEEP);

	pd3dDevice->SetRenderState(D3DRS_STENCILFAIL, D3DSTENCILOP_KEEP);

	pd3dDevice->SetRenderState(D3DRS_STENCILPASS, D3DSTENCILOP_REPLACE);



	pd3dDevice->SetRenderState(D3DRS_ZWRITEENABLE,		FALSE);

	pd3dDevice->SetRenderState(D3DRS_ALPHABLENDENABLE,	TRUE);

	pd3dDevice->SetRenderState(D3DRS_SRCBLEND,			D3DBLEND_ZERO);

	pd3dDevice->SetRenderState(D3DRS_DESTBLEND,			D3DBLEND_ONE);

	

	vector<CObject3D*> vecMirror;

	for(vector<CObject3D*>::iterator it=m_listOpaque.begin();it!=m_listOpaque.end();it++)

	{

		if((*it)->m_bIsMirror)

		{	

			D3DXVECTOR3 vNormal((*it)->m_plane.a,(*it)->m_plane.b,(*it)->m_plane.c);

			D3DXVECTOR3 vEye = *g_pX3DControl->m_Camera.GetEyePt()-(*it)->m_planeCenter;

			

			FLOAT fRes = D3DXVec3Dot(&vNormal, &vEye);

			if(fRes>=0.0f)

				continue;

			vecMirror.push_back(*it);

			(*it)->RenderOneStage(pd3dDevice, m_pAmbientStage, fTime, fElapsedTime);

		}

	}



	pd3dDevice->SetRenderState(D3DRS_ZWRITEENABLE, TRUE);



	m_bMirrorFlag = true;

	for(vector<CObject3D*>::iterator it=vecMirror.begin();it!=vecMirror.end();it++)

	{

		pd3dDevice->SetRenderState(D3DRS_STENCILFUNC, D3DCMP_EQUAL);

		pd3dDevice->SetRenderState(D3DRS_STENCILPASS, D3DSTENCILOP_KEEP);



		V(pd3dDevice->Clear(0, NULL, D3DCLEAR_ZBUFFER, 0, 1.0f, 0L));

		pd3dDevice->SetRenderState(D3DRS_SRCBLEND,  D3DBLEND_DESTCOLOR);

		pd3dDevice->SetRenderState(D3DRS_DESTBLEND, D3DBLEND_ZERO);



		D3DXMatrixReflect(&m_MatReflect, &(*it)->m_plane);

		StagesPerLight(pd3dDevice,fTime,fElapsedTime,NULL,(*it));

	}

	m_bMirrorFlag = false;



	pd3dDevice->SetRenderState(D3DRS_ALPHABLENDENABLE, FALSE);

	pd3dDevice->SetRenderState(D3DRS_STENCILENABLE,	 FALSE);



	return S_OK;