C++ Portal::cullDraw方法代码示例

void FunctionalPortal::createEnvironmentMap(const std::vector<Portal *> *portals){
	Portal *destPortal = (*portals)[iDestPortal];
	Vec3 portalPos = destPortal->getPos();
	Vec3 eyePos;
	vecAdd(&destPos_pcoord, &portalPos, &eyePos);

	bool oldHide = isHidden();
	setHide(true);

	GL_CHECK(glMatrixMode(GL_MODELVIEW));
	GL_CHECK(glPushMatrix());
	GL_CHECK(glMatrixMode(GL_PROJECTION));
	GL_CHECK(glPushMatrix());
	GL_CHECK(glPushAttrib(GL_VIEWPORT_BIT));

	//GL_CHECK(glBindTexture(GL_TEXTURE_2D, 0));
	tgr->bind();
	//GL_CHECK(glBindTexture(GL_TEXTURE_2D, dstDepthmap));
	//GL_CHECK(glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, GL_DEPTH_ATTACHMENT_EXT,
	//GL_TEXTURE_2D, dstDepthmap, 0));
	/*GLuint id = renderTgr->genColorTexutre();
	glFramebufferTexture2DEXT(
        GL_FRAMEBUFFER_EXT,
        GL_COLOR_ATTACHMENT0_EXT,
        GL_TEXTURE_2D,
        id,
        0);
		struct MAZErectangle viewport;
	viewport.left = 0;
	viewport.bottom = 0;
	viewport.width = width;
	viewport.height = height;
	struct Vec3 centerPos = vec2vecAdd(&eyePos, 0, 0, -10);
		glMatrixMode(GL_MODELVIEW);
		glLoadIdentity();
		gluLookAt(eyePos.x, eyePos.y, eyePos.z, 
				centerPos.x, centerPos.y, centerPos.z,
				0, 1, 0);
		glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
		struct MAZEmat projviewMat;
		struct MAZEmat viewportMat;

		getWindowProjMat(viewport, projviewMat, viewportMat);

		hash_set<int *> visitedEdgeSet;
		destPortal->cullDraw(&projviewMat, &viewportMat, viewport, 
							portals, visitedEdgeSet);
		
		glBindTexture(GL_TEXTURE_2D, id);
		//debug
	sf::Uint8 *pixelArray = new sf::Uint8[width*height*4];
	glGetTexImage(GL_TEXTURE_2D, 0, GL_RGBA, GL_UNSIGNED_BYTE, pixelArray); // to read from texture instead
	sf::Image temp(width, height, pixelArray);
	std::string filename = "envmap";
	//char a[2] = {'a'+i, '\0'};
	//filename.append(a);
	filename.append(".jpg");
	temp.SaveToFile(filename);
	return;*/

	glMatrixMode(GL_PROJECTION);
	GLfloat aspectRatio = 1.;
    GLfloat nearClip = 0.1f;
    GLfloat farClip = 400.0f;
    GLfloat fieldOfView = 90.0f; // Degrees

    glLoadIdentity();
    gluPerspective(fieldOfView, aspectRatio, nearClip, farClip);
	glViewport(0, 0, width, height);

	float lookVectors[24] = {
		1, 0, 0, 1,
		-1, 0, 0, 1,
		0, 1, 0, 1,
		0, -1, 0, 1,
		0, 0, 1, 1,
		0, 0, -1, 1
	};
	
	float up[24] = {
		0, -1, 0, 1,
		0, -1, 0, 1,
		0, 0, 1, 1,
		0, 0, -1, 1,
		0, -1, 0, 1,
		0, -1, 0, 1
	};

	struct MAZErectangle viewport;
	viewport.left = 0;
	viewport.bottom = 0;
	viewport.width = width;
	viewport.height = height;
	GL_CHECK(glBindTexture(GL_TEXTURE_CUBE_MAP, dstCubemap));
	struct Vec3 centerPos = vec2vecAdd(&eyePos, 
										lookVectors[direction*4], 
										lookVectors[direction*4+1], 
										lookVectors[direction*4+2]);
	glMatrixMode(GL_MODELVIEW);
	glLoadIdentity();
//.........这里部分代码省略.........

bool Portal::cullDraw(struct MAZEmat *projviewMat, struct MAZEmat *viewportMat, 
					struct MAZErectangle &rec, const std::vector<Portal *> *portals, set<int *> &visitedEdgeSet){
	MAZEmat finalProjViewMat;
	multMat(projviewMat, &transformation, &finalProjViewMat);

	//TODO: implement BV for objects
	glMatrixMode(GL_MODELVIEW);
	glPushMatrix();
	//glMultMatrixf(transformation.mat);
	if(!portalObj->isHidden())
		portalObj->draw(portals);
	for(int i=0; i<objs.size(); i++)
		if(!objs[i]->isHidden())
			objs[i]->draw(portals);

	glMatrixMode(GL_MODELVIEW);
	glPopMatrix();
	
	//What this portal looks like in its neighbors eye...
	int posMap[4] = {1, 0, 3, 2};

	for(int i=0; i<4; i++){
		if(neighbors[i] < 0)
			continue;

		//Have we visited this undirected edge? 
		//I know the following code seems a little hack
		//but I can't find any better way...
		Portal *port = (*portals)[neighbors[i]];
		if(visitedEdgeSet.count(port->getNeighbors()+posMap[i]) > 0 || 
			visitedEdgeSet.count(neighbors+i))
			continue;
		//int size1 = visitedEdgeSet.size();
		visitedEdgeSet.insert(neighbors+i);
		//int size2 = visitedEdgeSet.size();
		/*if(size2 == size1){
			cout << "not right" << endl;
		}*/
		//assert(visitedEdgeSet.size()<4*(*portals).size());
		//cout<<"visitedEdge " << visitedEdgeSet.size() << endl;
		struct Vec3 p[4];
		float left = MY_FLT_MAX, right = MY_FLT_MIN, top = MY_FLT_MIN, bottom = MY_FLT_MAX;
		float nearC = MY_FLT_MAX, farC = MY_FLT_MIN;
		for(int j=0; j<4; j++){
			struct Vec3 tmp;
			matMultVec3_normalize(&finalProjViewMat, &doorPoints[i][j], &tmp);
			matMultVec3_normalize(viewportMat, &tmp, p+j);
			if(p[j].x < left)
				left = p[j].x;
			if(p[j].x > right)
				right = p[j].x;

			if(p[j].y > top)
				top = p[j].y;
			if(p[j].y < bottom)
				bottom = p[j].y;

			if(p[j].z < nearC)
				nearC = p[j].z;

			if(p[j].z > farC)
				farC = p[j].z;
		}
		if(farC < 0 || nearC > 1)
			continue;

		left = left > rec.left ? left : rec.left;
		right = right < (rec.left+rec.width) ? right : rec.left+rec.width;
		bottom = bottom > rec.bottom ? bottom : rec.bottom;
		top = top < (rec.bottom + rec.height) ? top : rec.bottom+rec.height;
		MAZErectangle neighborRect;
		neighborRect.left = left;
		neighborRect.bottom = bottom;
		neighborRect.height = top-bottom;
		neighborRect.width = right-left;
		//This is necessary for edge condition
		if(neighborRect.height <= -1e-5 || neighborRect.width <= -1e-5)
			continue;
		
		//Door status switched. If it is open from this cell to its
		//neighbor, we might visit that neighbor. When we are visiting
		//the neighbor, we will close the door and would not visit this
		//cell. Is it still possible that we might loop back to visited portal?
		//If the door is open, visit it.
		//NOTE: Theorectically it's possible that a single object in a cell
		//can be rendered several times from different doors. TODO: I might add some
		//mask to handle this problem in the future. But, for this maze game,
		//this scenario seems unlikely. So ignore it for now.
		port->cullDraw(projviewMat, viewportMat, neighborRect, portals, visitedEdgeSet);
	}
	return true;
}