关于OpenGL的实例教程源代码

				/*
					Model.cpp
				
						Abstract base class for a model. The specific extended class will render the given model. 
				
					Author:	Brett Porter
					Email: brettporter@yahoo.com
					Website: http://www.geocities.com/brettporter/
					Copyright (C)2000, Brett Porter. All Rights Reserved.
				
					This file may be used only as long as this copyright notice remains intact.
				*/
				
				#include 		// Header File For Windows
				#include 			// Header File For The OpenGL32 Library
				
				#include "Model.h"
				#include "Lesson31.h"
				
				Model::Model()
				{
					m_numMeshes = 0;
					m_pMeshes = NULL;
					m_numMaterials = 0;
					m_pMaterials = NULL;
					m_numTriangles = 0;
					m_pTriangles = NULL;
					m_numVertices = 0;
					m_pVertices = NULL;
				}
				
				Model::~Model()
				{
					int i;
					for ( i = 0; i < m_numMeshes; i++ )
						delete[] m_pMeshes[i].m_pTriangleIndices;
					for ( i = 0; i < m_numMaterials; i++ )
						delete[] m_pMaterials[i].m_pTextureFilename;
				
					m_numMeshes = 0;
					if ( m_pMeshes != NULL )
					{
						delete[] m_pMeshes;
						m_pMeshes = NULL;
					}
				
					m_numMaterials = 0;
					if ( m_pMaterials != NULL )
					{
						delete[] m_pMaterials;
						m_pMaterials = NULL;
					}
				
					m_numTriangles = 0;
					if ( m_pTriangles != NULL )
					{
						delete[] m_pTriangles;
						m_pTriangles = NULL;
					}
				
					m_numVertices = 0;
					if ( m_pVertices != NULL )
					{
						delete[] m_pVertices;
						m_pVertices = NULL;
					}
				}
				
				void Model::draw() 
				{
					GLboolean texEnabled = glIsEnabled( GL_TEXTURE_2D );
				
					// Draw by group
					for ( int i = 0; i < m_numMeshes; i++ )
					{
						int materialIndex = m_pMeshes[i].m_materialIndex;
						if ( materialIndex >= 0 )
						{
							glMaterialfv( GL_FRONT, GL_AMBIENT, m_pMaterials[materialIndex].m_ambient );
							glMaterialfv( GL_FRONT, GL_DIFFUSE, m_pMaterials[materialIndex].m_diffuse );
							glMaterialfv( GL_FRONT, GL_SPECULAR, m_pMaterials[materialIndex].m_specular );
							glMaterialfv( GL_FRONT, GL_EMISSION, m_pMaterials[materialIndex].m_emissive );
							glMaterialf( GL_FRONT, GL_SHININESS, m_pMaterials[materialIndex].m_shininess );
				
							if ( m_pMaterials[materialIndex].m_texture > 0 )
							{
								glBindTexture( GL_TEXTURE_2D, m_pMaterials[materialIndex].m_texture );
								glEnable( GL_TEXTURE_2D );
							}
							else
								glDisable( GL_TEXTURE_2D );
						}
						else
						{
							// Material properties?
							glDisable( GL_TEXTURE_2D );
						}
				
						glBegin( GL_TRIANGLES );
						{
							for ( int j = 0; j < m_pMeshes[i].m_numTriangles; j++ )
							{
								int triangleIndex = m_pMeshes[i].m_pTriangleIndices[j];
								const Triangle* pTri = &m_pTriangles[triangleIndex];
				
								for ( int k = 0; k < 3; k++ )
								{
									int index = pTri->m_vertexIndices[k];
				
									glNormal3fv( pTri->m_vertexNormals[k] );
									glTexCoord2f( pTri->m_s[k], pTri->m_t[k] );
									glVertex3fv( m_pVertices[index].m_location );
								}
							}
						}
						glEnd();
					}
				
					if ( texEnabled )
						glEnable( GL_TEXTURE_2D );
					else
						glDisable( GL_TEXTURE_2D );
				}
				
				void Model::reloadTextures()
				{
					for ( int i = 0; i < m_numMaterials; i++ )
						if ( strlen( m_pMaterials[i].m_pTextureFilename ) > 0 )
							m_pMaterials[i].m_texture = LoadGLTexture( m_pMaterials[i].m_pTextureFilename );
						else
							m_pMaterials[i].m_texture = 0;
				}