alternate rendering loop

psychopath · 07-16-2005, 09:50 AM

I have a loop that runs through polygons and verticies to render a model (the basic routine). It works fine, except I need it to loop differently, to work with a collision library.

Code:

		glBegin( GL_TRIANGLES );
		{
			for ( int j = 0; j < objectP->m_pMeshes[i].m_numTriangles; j++ )
			{
				int triangleIndex = objectP->m_pMeshes[i].m_pTriangleIndices[j];
				const Triangle *pTri = &objectP->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( objectP->m_pVertices[index].m_location );
				}
			}
		}
		glEnd();

The bolded code is the main problem. For each triangle, it then loops through 3 verticies. I want it to do 3 verticies at once....

Code:

for(blah blah...<numtris..blah)
{
    glVertex3f(...);
    glVertex3f(...);
    glVertex3f(...);
}

...but i'm not sure how to go about it. Iv'e tried different things, but I just end up with severe poly scattering. I'm not sure if i'm making sense, but if I am, please help!

thanx
-psychopath

no-one · 07-16-2005, 11:20 AM

this should work unless i am missing something?

Code:

glBegin( GL_TRIANGLES );
{
	for ( int j = 0; j < objectP->m_pMeshes[i].m_numTriangles; j++ )
	{
		int triangleIndex = objectP->m_pMeshes[i].m_pTriangleIndices[j];
		const Triangle *pTri = &objectP->m_pTriangles[triangleIndex];
				
		int index = pTri->m_vertexIndices[0];
					
		glNormal3fv( pTri->m_vertexNormals[0] );
		glTexCoord2f( pTri->m_s[0], pTri->m_t[0] );
		glVertex3fv( objectP->m_pVertices[index].m_location );

		int index = pTri->m_vertexIndices[1];
					
		glNormal3fv( pTri->m_vertexNormals[1] );
		glTexCoord2f( pTri->m_s[1], pTri->m_t[1] );
		glVertex3fv( objectP->m_pVertices[index].m_location );

		int index = pTri->m_vertexIndices[2];
					
		glNormal3fv( pTri->m_vertexNormals[2] );
		glTexCoord2f( pTri->m_s[2], pTri->m_t[2] );
		glVertex3fv( objectP->m_pVertices[index].m_location );
	}
}
glEnd();

psychopath · 07-16-2005, 12:30 PM

Naturally, the one thing I didn't try would be the solution :P.
Thanx, It works perfectly. Now all I have to do is work out the bugs in the collision system. *cringes*

-psychopath

07-16-2005, 09:50 AM	#1
psychopath The Right Honourable Join Date: Mar 2004 Location: Where circles begin. Posts: 1,068	alternate rendering loop I have a loop that runs through polygons and verticies to render a model (the basic routine). It works fine, except I need it to loop differently, to work with a collision library. Code: glBegin( GL_TRIANGLES ); { for ( int j = 0; j < objectP->m_pMeshes[i].m_numTriangles; j++ ) { int triangleIndex = objectP->m_pMeshes[i].m_pTriangleIndices[j]; const Triangle *pTri = &objectP->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( objectP->m_pVertices[index].m_location ); } } } glEnd(); The bolded code is the main problem. For each triangle, it then loops through 3 verticies. I want it to do 3 verticies at once.... Code: for(blah blah...<numtris..blah) { glVertex3f(...); glVertex3f(...); glVertex3f(...); } ...but i'm not sure how to go about it. Iv'e tried different things, but I just end up with severe poly scattering. I'm not sure if i'm making sense, but if I am, please help! thanx -psychopath __________________ Memorial University of Newfoundland Computer Science www.daniel-cook.net Mac and OpenGL evangelist.
psychopath is offline

07-16-2005, 12:30 PM	#3
psychopath The Right Honourable Join Date: Mar 2004 Location: Where circles begin. Posts: 1,068	Naturally, the one thing I didn't try would be the solution :P. Thanx, It works perfectly. Now all I have to do is work out the bugs in the collision system. cringes -psychopath __________________ Memorial University of Newfoundland Computer Science www.daniel-cook.net Mac and OpenGL evangelist.
psychopath is offline

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