//////////////////////////////////////////////////////////////////////////// Function: loadTerrain//// Purpose:  Loads terrain from a .X file//////////////////////////////////////////////////////////////////////////MPRESULT CTerrainManager::loadTerrain(char* a_pcTerrainFile){	// Singletons	CLoadscreen* pLodSrn		= CLoadscreen::getInstance();	// Open the file for reading	HANDLE file = CreateFile(a_pcTerrainFile, GENERIC_READ, 0, NULL, OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);	// Now we need to find out how big the actual file is	// We allow one byte for the NULL terminator	DWORD fileSize = GetFileSize(file, NULL) + 1;	// This character array will store the entire file contents	char *fileAsText = new char[fileSize];	// Start with a NULL string so we don't have any garbage to screw things up	memset(fileAsText, 0, fileSize);	// ReadFile needs a DWORD as one of the parameters	DWORD bytesRead;	// Read the file into our string for the amount of bytes taken from GetFileSize	ReadFile(file, fileAsText, fileSize - 1, &bytesRead, NULL);	// If you create a handle, you have to close it as well	CloseHandle(file);		// The will hold the bounding volumes for the mesh as a whole	// These values will be used to set up the quad tree	// We start the at the highest and lowest values they can store so that the	// first position we come across over writes them	float minX, minZ, maxX, maxZ;	minX = minZ = FLT_MAX;	maxX = maxZ = FLT_MIN;	// At this point we have loaded the file and can start parsing it	// We'll start by finding the chunck of data containing the mesh	char* placeHolder = strstr(fileAsText, "Mesh ");	// We then want to skip to the end of that line	placeHolder = strstr(placeHolder, "\n");	// And now their are 4 characters before we get to the data	placeHolder += 4;	// We are now sitting right infront of the number of verts, so lets read them in!	sscanf(placeHolder, "%d;", &vertexCount);	// We then want to skip to the end of that line	placeHolder = strstr(placeHolder, "\n");	// And now their are 4 characters before we get to the next data	placeHolder += 4;	// With all the proper counters set up we can now allocate some memory to 	// store the verts and indicies	verticies	= new CCustomVertexDefault[vertexCount];		// Let start with a clean slate and memset out vertex array	memset(verticies, 0, sizeof(CCustomVertexDefault) * vertexCount);	// Reset the loading screen task	pLodSrn->setNewTask("Loading Terrain Verts");	// Now that we have the vertex count we can loop through and load the vert data	for(int i = 0; i < vertexCount; i++)	{		// The vertex data looks something like this:		// -50.000000;-0.000000;50.000000;,		// Line after line of coordinates, so lets read them in		// Start by creating some temp variables to make reading in the data a little		// easier		float x, y, z;		// Now read into those temp variables		sscanf(placeHolder, "%f;%f;%f;,", &x, &y, &z);		// Now copy that data into the real verticies		verticies.m_vec3Translation.x = x;		verticies.m_vec3Translation.y = y;		verticies.m_vec3Translation.z = z;		verticies.m_vec3Normal.y = 1.0f;		// Lets check if we have extended the bounds at all		if(x < minX)			minX = x;		if(x > maxX)			maxX = x;		if(z < minZ)			minZ = z;		if(z > maxZ)			maxZ = z;		// We then want to skip to the end of that line		placeHolder = strstr(placeHolder, "\n");		// And now their are 4 characters before we get to the next data		placeHolder += 4;	}	// Awesome!  So at this point we have all the verts loaded in an we're even left	// with our place holder point right at the start of the index data!  Lets load it.	// Like the verts, the first thing we need to do is find out how many there are	// In this case though, it is telling us how many primitives their are	sscanf(placeHolder, "%d", &primativeCount);	// With that in mind though, its a simple calculation to get the number of	// indicies	indexCount = primativeCount * 3;	// We then want to skip to the end of that line	placeHolder = strstr(placeHolder, "\n");	// And now their are 6 characters before we get to the data	placeHolder += 6;	// With the number of indicies know to us we can allocate some memory	indicies	= new WORD[indexCount];	// Reset the loading screen task	pLodSrn->setNewTask("Loading Terrain Indicies");	// Now we just fly through the data loading in the indicies	for(i = 0; i < indexCount; )	{		// A line of data for indices looks like this:		//    3;0,1,11;,		// But since we skipped 6 characters this time we are right after the '3;'		// We do this because all the 3 is for is to tell us how many indicies are		// on this line (3 means we are using triangles too).  But since the entire model 		// is the same (in this sense), it says 3 everytime, so lets just skip over it		// Once again lets create some temp variables		int a, b, c;		// And lets read the data into those variables		sscanf(placeHolder, "%d,%d,%d", &a, &b, &c);		// Now we need to cycle through and store these indicies		indicies = a;		i++;		indicies = b;		i++;		indicies = c;		i++;		// We then want to skip to the end of that line		placeHolder = strstr(placeHolder, "\n");		// And now their are 6 characters before we get to the data		placeHolder += 6;	}	// Now we can create our quad tree	boxf bounds;	bounds.min.x = minX;	bounds.min.z = minZ;	bounds.max.x = maxX;	bounds.max.z = MaxZ;	m_pQTree = new quad_tree(bounds);	// Reset the loading screen task	pLodSrn->setNewTask("Populating Quad Tree");		for(i = 0; i < indexCount; i += 3)	{		polygon newPoly;		newPoly.verts[0] = verticies[indicies].m_vec3Translation;		newPoly.verts[1] = verticies[indicies].m_vec3Translation;<br>		newPoly.verts[<span class="cpp-number">2</span>] = verticies[indicies].m_vec3Translation;<br>		m_pQTree-&gt;addPoly(newPoly);<br>	}<br><br>	<span class="cpp-comment">// Finally lets clean up the memory</span><br>	<span class="cpp-keyword">delete</span> [] fileAsText;<br>	<br>	<span class="cpp-comment">// Everything went great</span><br>	<span class="cpp-keyword">return</span> MPERR_OK;<br>}<br><br><br></pre></div><!–ENDSCRIPT–><br><br>If you open up an x file in note pad, you can follow along with all the pointer arithmetic.  It's a little ugly, but quite simple at its core.<br><br>Matt Hughson