tutorial_31.htm

如果你相信它就好好学学吧,同样这里也只是个入门

    <td valign="top" width="100%">这里我们使用与OpenGL中相对的材质。 <p>下面的代码用来载入模型，我们通过重载loadModelData函数来实现它。</p>
      我们创建了一个新类MilkshapeModel,它是从Model继承而来的。</td>
    <td background="Tutorial_31_files/r.png"><img src="Tutorial_31_files/r.png"></td></tr></tbody></table><table border="0" cellpadding="0" cellspacing="0" width="100%"><tbody><tr><td><img src="Tutorial_31_files/bl.png" height="28" width="28"></td><td width="100%"><img src="Tutorial_31_files/bc.png" height="28" width="100%"></td><td><img src="Tutorial_31_files/br.png" height="28" width="28"></td></tr></tbody></table><font color="#aaffaa" size="3">
<pre>bool MilkshapeModel::loadModelData( const char *filename )
{
	ifstream inputFile( filename, ios::in | ios::binary | ios::nocreate );
	if ( inputFile.fail())
		return false;	<font color="#ffffaa">// 不能打开文件，返回失败</font>
</pre>
</font><table border="0" cellpadding="0" cellspacing="0" width="100%"><tbody><tr><td><img src="Tutorial_31_files/tl.png" height="28" width="28"></td><td width="100%"><img src="Tutorial_31_files/tc.png" height="28" width="100%"></td><td><img src="Tutorial_31_files/tr.png" height="28" width="28"></td></tr></tbody></table><table border="0" cellpadding="0" cellspacing="0" width="100%"><tbody><tr><td background="Tutorial_31_files/l.png"><img src="Tutorial_31_files/l.png"></td>
    <td valign="top" width="100%">以二进制的方式打开文件，如果失败则返回</td>
    <td background="Tutorial_31_files/r.png"><img src="Tutorial_31_files/r.png"></td></tr></tbody></table><table border="0" cellpadding="0" cellspacing="0" width="100%"><tbody><tr><td><img src="Tutorial_31_files/bl.png" height="28" width="28"></td><td width="100%"><img src="Tutorial_31_files/bc.png" height="28" width="100%"></td><td><img src="Tutorial_31_files/br.png" height="28" width="28"></td></tr></tbody></table><font color="#aaffaa" size="3"><pre>	inputFile.seekg( 0, ios::end );
	long fileSize = inputFile.tellg();
	inputFile.seekg( 0, ios::beg );
</pre></font><table border="0" cellpadding="0" cellspacing="0" width="100%"><tbody><tr><td><img src="Tutorial_31_files/tl.png" height="28" width="28"></td><td width="100%"><img src="Tutorial_31_files/tc.png" height="28" width="100%"></td><td><img src="Tutorial_31_files/tr.png" height="28" width="28"></td></tr></tbody></table><table border="0" cellpadding="0" cellspacing="0" width="100%"><tbody><tr><td background="Tutorial_31_files/l.png"><img src="Tutorial_31_files/l.png"></td>
    <td valign="top" width="100%">返回文件大小</td>
    <td background="Tutorial_31_files/r.png"><img src="Tutorial_31_files/r.png"></td></tr></tbody></table><table border="0" cellpadding="0" cellspacing="0" width="100%"><tbody><tr><td><img src="Tutorial_31_files/bl.png" height="28" width="28"></td><td width="100%"><img src="Tutorial_31_files/bc.png" height="28" width="100%"></td><td><img src="Tutorial_31_files/br.png" height="28" width="28"></td></tr></tbody></table><font color="#aaffaa" size="3"><pre>	byte *pBuffer = new byte[fileSize];
	inputFile.read( pBuffer, fileSize );
	inputFile.close();
</pre></font><table border="0" cellpadding="0" cellspacing="0" width="100%"><tbody><tr><td><img src="Tutorial_31_files/tl.png" height="28" width="28"></td><td width="100%"><img src="Tutorial_31_files/tc.png" height="28" width="100%"></td><td><img src="Tutorial_31_files/tr.png" height="28" width="28"></td></tr></tbody></table><table border="0" cellpadding="0" cellspacing="0" width="100%"><tbody><tr><td background="Tutorial_31_files/l.png"><img src="Tutorial_31_files/l.png"></td>
    <td valign="top" width="100%">分配一个内存，载入文件，并关闭文件</td>
    <td background="Tutorial_31_files/r.png"><img src="Tutorial_31_files/r.png"></td></tr></tbody></table><table border="0" cellpadding="0" cellspacing="0" width="100%"><tbody><tr><td><img src="Tutorial_31_files/bl.png" height="28" width="28"></td><td width="100%"><img src="Tutorial_31_files/bc.png" height="28" width="100%"></td><td><img src="Tutorial_31_files/br.png" height="28" width="28"></td></tr></tbody></table><font color="#aaffaa" size="3">
</font><pre><font color="#aaffaa" size="3">	const byte *pPtr = pBuffer;
	MS3DHeader *pHeader = ( MS3DHeader* )pPtr;
	pPtr += sizeof( MS3DHeader );

	if ( strncmp( pHeader-&gt;m_ID, "MS3D000000", 10 ) != 0 )
		return false;	<font color="#ffffaa">// 如果不是一个有效的MS3D文件则返回</font>

	if ( pHeader-&gt;m_version &lt; 3 || pHeader-&gt;m_version &gt; 4 )
		return false;	<font color="#ffffaa">// 如果不能支持这种版本的文件，则返回失败</font></font></pre>
<table border="0" cellpadding="0" cellspacing="0" width="100%"><tbody><tr><td><img src="Tutorial_31_files/tl.png" height="28" width="28"></td><td width="100%"><img src="Tutorial_31_files/tc.png" height="28" width="100%"></td><td><img src="Tutorial_31_files/tr.png" height="28" width="28"></td></tr></tbody></table><table border="0" cellpadding="0" cellspacing="0" width="100%"><tbody><tr><td background="Tutorial_31_files/l.png"><img src="Tutorial_31_files/l.png"></td>
    <td valign="top" width="100%">上面的文件读取文件头</td>
    <td background="Tutorial_31_files/r.png"><img src="Tutorial_31_files/r.png"></td></tr></tbody></table><table border="0" cellpadding="0" cellspacing="0" width="100%"><tbody><tr><td><img src="Tutorial_31_files/bl.png" height="28" width="28"></td><td width="100%"><img src="Tutorial_31_files/bc.png" height="28" width="100%"></td><td><img src="Tutorial_31_files/br.png" height="28" width="28"></td></tr></tbody></table><font color="#aaffaa" size="3"><pre>	int nVertices = *( word* )pPtr;
	m_numVertices = nVertices;
	m_pVertices = new Vertex[nVertices];
	pPtr += sizeof( word );

	int i;
	for ( i = 0; i &lt; nVertices; i++ )
	{
		MS3DVertex *pVertex = ( MS3DVertex* )pPtr;
		m_pVertices[i].m_boneID = pVertex-&gt;m_boneID;
		memcpy( m_pVertices[i].m_location, pVertex-&gt;m_vertex, sizeof( float )*3 );
		pPtr += sizeof( MS3DVertex );
	}
</pre></font><table border="0" cellpadding="0" cellspacing="0" width="100%"><tbody><tr><td><img src="Tutorial_31_files/tl.png" height="28" width="28"></td><td width="100%"><img src="Tutorial_31_files/tc.png" height="28" width="100%"></td><td><img src="Tutorial_31_files/tr.png" height="28" width="28"></td></tr></tbody></table><table border="0" cellpadding="0" cellspacing="0" width="100%"><tbody><tr><td background="Tutorial_31_files/l.png"><img src="Tutorial_31_files/l.png"></td>
    <td valign="top" width="100%">上面的代码读取顶点数据</td>
    <td background="Tutorial_31_files/r.png"><img src="Tutorial_31_files/r.png"></td></tr></tbody></table><table border="0" cellpadding="0" cellspacing="0" width="100%"><tbody><tr><td><img src="Tutorial_31_files/bl.png" height="28" width="28"></td><td width="100%"><img src="Tutorial_31_files/bc.png" height="28" width="100%"></td><td><img src="Tutorial_31_files/br.png" height="28" width="28"></td></tr></tbody></table><font color="#aaffaa" size="3"><pre>	int nTriangles = *( word* )pPtr;
	m_numTriangles = nTriangles;
	m_pTriangles = new Triangle[nTriangles];
	pPtr += sizeof( word );

	for ( i = 0; i &lt; nTriangles; i++ )
	{
		MS3DTriangle *pTriangle = ( MS3DTriangle* )pPtr;
		int vertexIndices[3] = { pTriangle-&gt;m_vertexIndices[0], pTriangle-&gt;m_vertexIndices[1], pTriangle-&gt;m_vertexIndices[2] };
		float t[3] = { 1.0f-pTriangle-&gt;m_t[0], 1.0f-pTriangle-&gt;m_t[1], 1.0f-pTriangle-&gt;m_t[2] };
		memcpy( m_pTriangles[i].m_vertexNormals, pTriangle-&gt;m_vertexNormals, sizeof( float )*3*3 );
		memcpy( m_pTriangles[i].m_s, pTriangle-&gt;m_s, sizeof( float )*3 );
		memcpy( m_pTriangles[i].m_t, t, sizeof( float )*3 );
		memcpy( m_pTriangles[i].m_vertexIndices, vertexIndices, sizeof( int )*3 );
		pPtr += sizeof( MS3DTriangle );
	}
</pre></font><table border="0" cellpadding="0" cellspacing="0" width="100%"><tbody><tr><td><img src="Tutorial_31_files/tl.png" height="28" width="28"></td><td width="100%"><img src="Tutorial_31_files/tc.png" height="28" width="100%"></td><td><img src="Tutorial_31_files/tr.png" height="28" width="28"></td></tr></tbody></table><table border="0" cellpadding="0" cellspacing="0" width="100%"><tbody><tr><td background="Tutorial_31_files/l.png"><img src="Tutorial_31_files/l.png"></td>
    <td valign="top" width="100%">上面的代码用来读取三角形信息，因为MS3D使用窗口坐标系而OpenGL使用笛卡儿坐标系，所以需要反转每个顶点Y方向的纹理坐标</td>
    <td background="Tutorial_31_files/r.png"><img src="Tutorial_31_files/r.png"></td></tr></tbody></table><table border="0" cellpadding="0" cellspacing="0" width="100%"><tbody><tr><td><img src="Tutorial_31_files/bl.png" height="28" width="28"></td><td width="100%"><img src="Tutorial_31_files/bc.png" height="28" width="100%"></td><td><img src="Tutorial_31_files/br.png" height="28" width="28"></td></tr></tbody></table><font color="#aaffaa" size="3">
<pre>	int nGroups = *( word* )pPtr;
	m_numMeshes = nGroups;
	m_pMeshes = new Mesh[nGroups];
	pPtr += sizeof( word );
	for ( i = 0; i &lt; nGroups; i++ )
	{
		pPtr += sizeof( byte );	
		pPtr += 32;	

		word nTriangles = *( word* )pPtr;
		pPtr += sizeof( word );
		int *pTriangleIndices = new int[nTriangles];
		for ( int j = 0; j &lt; nTriangles; j++ )
		{
			pTriangleIndices[j] = *( word* )pPtr;
			pPtr += sizeof( word );
		}

		char materialIndex = *( char* )pPtr;
		pPtr += sizeof( char );

		m_pMeshes[i].m_materialIndex = materialIndex;
		m_pMeshes[i].m_numTriangles = nTriangles;
		m_pMeshes[i].m_pTriangleIndices = pTriangleIndices;
	}
</pre>
</font><table border="0" cellpadding="0" cellspacing="0" width="100%"><tbody><tr><td><img src="Tutorial_31_files/tl.png" height="28" width="28"></td><td width="100%"><img src="Tutorial_31_files/tc.png" height="28" width="100%"></td><td><img src="Tutorial_31_files/tr.png" height="28" width="28"></td></tr></tbody></table><table border="0" cellpadding="0" cellspacing="0" width="100%"><tbody><tr><td background="Tutorial_31_files/l.png"><img src="Tutorial_31_files/l.png"></td>
    <td valign="top" width="100%">上面的代码填充网格结构</td>
    <td background="Tutorial_31_files/r.png"><img src="Tutorial_31_files/r.png"></td></tr></tbody></table><table border="0" cellpadding="0" cellspacing="0" width="100%"><tbody><tr><td><img src="Tutorial_31_files/bl.png" height="28" width="28"></td><td width="100%"><img src="Tutorial_31_files/bc.png" height="28" width="100%"></td><td><img src="Tutorial_31_files/br.png" height="28" width="28"></td></tr></tbody></table><font color="#aaffaa" size="3"><pre>	int nMaterials = *( word* )pPtr;
	m_numMaterials = nMaterials;
	m_pMaterials = new Material[nMaterials];
	pPtr += sizeof( word );
	for ( i = 0; i &lt; nMaterials; i++ )
	{
		MS3DMaterial *pMaterial = ( MS3DMaterial* )pPtr;
		memcpy( m_pMaterials[i].m_ambient, pMaterial-&gt;m_ambient, sizeof( float )*4 );
		memcpy( m_pMaterials[i].m_diffuse, pMaterial-&gt;m_diffuse, sizeof( float )*4 );
		memcpy( m_pMaterials[i].m_specular, pMaterial-&gt;m_specular, sizeof( float )*4 );
		memcpy( m_pMaterials[i].m_emissive, pMaterial-&gt;m_emissive, sizeof( float )*4 );
		m_pMaterials[i].m_shininess = pMaterial-&gt;m_shininess;
		m_pMaterials[i].m_pTextureFilename = new char[strlen( pMaterial-&gt;m_texture )+1];
		strcpy( m_pMaterials[i].m_pTextureFilename, pMaterial-&gt;m_texture );
		pPtr += sizeof( MS3DMaterial );
	}

	reloadTextures();
</pre></font><table border="0" cellpadding="0" cellspacing="0" width="100%"><tbody><tr><td><img src="Tutorial_31_files/tl.png" height="28" width="28"></td><td width="100%"><img src="Tutorial_31_files/tc.png" height="28" width="100%"></td><td><img src="Tutorial_31_files/tr.png" height="28" width="28"></td></tr></tbody></table><table border="0" cellpadding="0" cellspacing="0" width="100%"><tbody><tr><td background="Tutorial_31_files/l.png"><img src="Tutorial_31_files/l.png"></td>
    <td valign="top" width="100%">上面的代码加载纹理数据</td>
    <td background="Tutorial_31_files/r.png"><img src="Tutorial_31_files/r.png"></td></tr></tbody></table><table border="0" cellpadding="0" cellspacing="0" width="100%"><tbody><tr><td><img src="Tutorial_31_files/bl.png" height="28" width="28"></td><td width="100%"><img src="Tutorial_31_files/bc.png" height="28" width="100%"></td><td><img src="Tutorial_31_files/br.png" height="28" width="28"></td></tr></tbody></table><font color="#aaffaa" size="3"><pre>	delete[] pBuffer;

	return true;
}
</pre></font><table border="0" cellpadding="0" cellspacing="0" width="100%"><tbody><tr><td><img src="Tutorial_31_files/tl.png" height="28" width="28"></td><td width="100%"><img src="Tutorial_31_files/tc.png" height="28" width="100%"></td><td><img src="Tutorial_31_files/tr.png" height="28" width="28"></td></tr></tbody></table><table border="0" cellpadding="0" cellspacing="0" width="100%"><tbody><tr><td background="Tutorial_31_files/l.png"><img src="Tutorial_31_files/l.png"></td>
    <td valign="top" width="100%">上面的代码设置好了一切参数，但纹理还没有载入内存，下面的代码完成这个功能。</td>
    <td background="Tutorial_31_files/r.png"><img src="Tutorial_31_files/r.png"></td></tr></tbody></table><table border="0" cellpadding="0" cellspacing="0" width="100%"><tbody><tr><td><img src="Tutorial_31_files/bl.png" height="28" width="28"></td><td width="100%"><img src="Tutorial_31_files/bc.png" height="28" width="100%"></td><td><img src="Tutorial_31_files/br.png" height="28" width="28"></td></tr></tbody></table><font color="#aaffaa" size="3"><pre>void Model::reloadTextures()
{
	for ( int i = 0; i &lt; m_numMaterials; i++ )
		if ( strlen( m_pMaterials[i].m_pTextureFilename ) &gt; 0 )
			m_pMaterials[i].m_texture = LoadGLTexture( m_pMaterials[i].m_pTextureFilename );
		else
			m_pMaterials[i].m_texture = 0;
}