main.cpp

Quake中的MD2模型导入

{
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);	// Clear The Screen And The Depth Buffer
	glLoadIdentity();									// Reset The matrix

//////////// *** NEW *** ////////// *** NEW *** ///////////// *** NEW *** ////////////////////

	// Give OpenGL our position,	then view,		then up vector
	gluLookAt(		0, 1.5f, 90,		0, 0.5f, 0,			0, 1, 0);
	
	// We want the model to rotate around the axis so we give it a rotation
	// value, then increase/decrease it. You can rotate right of left with the arrow keys.

	glRotatef(g_RotateX, 0, 1.0f, 0);						// Rotate the object around the Y-Axis
	g_RotateX += g_RotationSpeed;							// Increase the speed of rotation

	// Make sure we have valid objects just in case. (size() is in the vector class)
	if(g_3DModel.pObject.size() <= 0) return;

	// Get the current object that we are displaying
	t3DObject *pObject = &g_3DModel.pObject[0];

	// Render lines or normal triangles mode, depending on the global variable
	glBegin(g_ViewMode);

		// Go through all of the faces (polygons) of the object and draw them
		for(int j = 0; j < pObject->numOfFaces; j++)
		{
			// Go through each corner of the triangle and draw it.
			for(int whichVertex = 0; whichVertex < 3; whichVertex++)
			{
				// Get the index for each point in the face
				int index = pObject->pFaces[j].vertIndex[whichVertex];

				// Get the index for each texture coord in the face
				int index2 = pObject->pFaces[j].coordIndex[whichVertex];
			
				// Give OpenGL the normal for this vertex.  Notice that we put a 
				// - sign in front.  It appears that because of the ordering of Quake2's
				// polygons, we need to invert the normal
				glNormal3f(-pObject->pNormals[ index ].x, -pObject->pNormals[ index ].y, -pObject->pNormals[ index ].z);
					
				// Make sure there was a UVW map applied to the object or else it won't have tex coords.
				if(pObject->pTexVerts) 
				{
					glTexCoord2f(pObject->pTexVerts[ index2 ].x, pObject->pTexVerts[ index2 ].y);
				}
				
				// Pass in the current vertex of the object (Corner of current face)
				glVertex3f(pObject->pVerts[ index ].x, pObject->pVerts[ index ].y, pObject->pVerts[ index ].z);
			}
		}

	glEnd();

//////////// *** NEW *** ////////// *** NEW *** ///////////// *** NEW *** ////////////////////

	SwapBuffers(g_hDC);									// Swap the backbuffers to the foreground
}

///////////////////////////////// WIN PROC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*
/////
/////	This function handles the window messages.
/////
///////////////////////////////// WIN PROC \\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\*

LRESULT CALLBACK WinProc(HWND hWnd,UINT uMsg, WPARAM wParam, LPARAM lParam)
{
    LONG    lRet = 0; 
    PAINTSTRUCT    ps;

    switch (uMsg)
	{ 
    case WM_SIZE:										// If the window is resized
		if(!g_bFullScreen)								// Do this only if we are NOT in full screen
		{
			SizeOpenGLScreen(LOWORD(lParam),HIWORD(lParam));// LoWord=Width, HiWord=Height
			GetClientRect(hWnd, &g_rRect);				// Get the window rectangle
		}
        break; 
 
	case WM_PAINT:										// If we need to repaint the scene
		BeginPaint(hWnd, &ps);							// Init the paint struct		
		EndPaint(hWnd, &ps);							// EndPaint, Clean up
		break;

//////////// *** NEW *** ////////// *** NEW *** ///////////// *** NEW *** ////////////////////

	// Below we define our controls for this simple tutorial.
	// The controls are: 

	// Left Mouse Button - Changes the Render mode from normal to wireframe.
	// Right Mouse Button - Turns lighting On/Off
	// Left Arrow Key - Spins the model to the left
	// Right Arrow Key - Spins the model to the right
	// Escape - Quits

	case WM_LBUTTONDOWN:								// If the left mouse button was clicked
		
		if(g_ViewMode == GL_TRIANGLES) {				// We our drawing mode is at triangles
			g_ViewMode = GL_LINE_STRIP;					// Go to line stips
		} else {
			g_ViewMode = GL_TRIANGLES;					// Go to triangles
		}
		break;

	case WM_RBUTTONDOWN:								// If the right mouse button was clicked.
		
		g_bLighting = !g_bLighting;						// Turn lighting ON/OFF

		if(g_bLighting) {								// If lighting is ON
			glEnable(GL_LIGHTING);						// Enable OpenGL lighting
		} else {
			glDisable(GL_LIGHTING);						// Disable OpenGL lighting
		}
		break;

	case WM_KEYDOWN:									// If we pressed a key

		switch(wParam) {								// Check if we hit a key
			case VK_ESCAPE:								// If we hit the escape key
				PostQuitMessage(0);						// Send a QUIT message to the window
				break;

			case VK_LEFT:								// If the LEFT arrow key was pressed
				g_RotationSpeed -= 0.05f;				// Decrease the rotation speed (eventually rotates left)
				break;

			case VK_RIGHT:								// If the RIGHT arrow key is pressed
				g_RotationSpeed += 0.05f;				// Increase the rotation speed (rotates right)
				break;
		}
		break;

//////////// *** NEW *** ////////// *** NEW *** ///////////// *** NEW *** ////////////////////


    case WM_CLOSE:										// If the window is being closed
        PostQuitMessage(0);								// Send a QUIT Message to the window
        break; 
     
    default:											// Return by default
        lRet = DefWindowProc (hWnd, uMsg, wParam, lParam); 
        break; 
    } 
 
    return lRet;										// Return by default
}

/////////////////////////////////////////////////////////////////////////////////
//
// * QUICK NOTES * 
//
// This tutorial shows how to load a .Md2 file.  This is a good addition to an engine.
// In the next tutorial we will show you how to handle the key frame animation.
// I think this is the best and easiest 3D file format I have worked with, especially
// for animation.
// 
// * What's An STL (Standard Template Library) Vector? *
// Let me quickly explain the STL vector for those of you who are not familiar with them.
// To use a vector you must include <vector> and use the std namespace: using namespace std;
// A vector is an array based link list.  It allows you to dynamically add and remove nodes.
// This is a template class so it can be a list of ANY type.  To create a vector of type
// "int" you would say:  vector<int> myIntList;
// Now you can add a integer to the dynamic array by saying: myIntList.push_back(10);
// or you can say:  myIntList.push_back(num);.  The more you push back, the larger
// your array gets.  You can index the vector like an array.  myIntList[0] = 0;
// To get rid of a node you use the pop_back() function.  To clear the vector use clear().
// It frees itself so you don't need to worry about it, except if you have data
// structures that need information freed from inside them, like our objects.
//
// Once again I should point out that the coordinate system of OpenGL and .Md2 files are different.
// Since Quake2 Models have the Z-Axis pointing up (strange and ugly I know! :), 
// we need to flip the y values with the z values in our vertices.  That way it
// will be normal, with Y pointing up.  Also, because we swap the Y and Z we need to negate 
// the Z to make it come out correctly.  This is also explained and done in ReadMd2Data().
//
// I would like to thank Daniel E. Schoenblum <[e-mail]> for help
// with explaining the file format.  You can check it out at:  
// 
// http://www.ugrad.cs.jhu.edu/~dansch/md2/#model_magic
//
// Let me know if this helps you out!
// 
// 
// Ben Humphrey (DigiBen)
// Game Programmer
// [e-mail]
// Co-Web Host of www.GameTutorials.com
//
// The Quake2 .Md2 file format is owned by ID Software.  This tutorial is being used 
// as a teaching tool to help understand model loading and animation.  This should
// not be sold or used under any way for commercial use with out written conset
// from ID Software.
//
// Quake and Quake2 are trademarks of id Software.
// All trademarks used are properties of their respective owners. 
//
//