About road texturing. I wanted to learn how BIS textured and setup their rvmats for roads, so I went into the roads.pbo and in data/ directory.

There we find road types of:

asf = asphalt (clean)
ces = dirt/gravel
kos = cobblestone
sil = asphalt (with white lane paintings)

First in the roads\asf6.p3d model you have the roads\data\asf_new_ca.tga texture with roads\data\asf.rvmat applied. The asf.rvmat looks like this:

ambient[] = {1.0, 1.0, 1.0, 1.0};
diffuse[] = {1.0, 1.0, 1.0, 1.0};
forcedDiffuse[] = {0.0, 0.0, 0.0, 0.0};
emmisive[] = {0.0, 0.0, 0.0, 1.0};
specular[] = {1.0, 1.0, 1.0, 0.0};
specularPower = 20.0;
renderFlags[] = {"Road"};
nextPass = "ca\roads\data\road-pass2.rvmat";
PixelShaderID = "NormalMapSpecularMap";
VertexShaderID = "NormalMap";
 
class Stage1
{
	texture = "ca\roads\data\asf_new_nohq.paa";
	uvSource = "tex";
 
	class uvTransform
	{
		aside[] = {1.0, 0.0, 0.0};
		up[] = {0.0, 1.0, 0.0};
		dir[] = {0.0, 0.0, 0.0};
		pos[] = {0.0, 0.0, 0.0};
	};
};
 
class Stage2
{
	texture = "ca\roads\data\asf_new_sm.paa";
	uvSource = "tex";
 
	class uvTransform
	{
		aside[] = {1.0, 0.0, 0.0};
		up[] = {0.0, 1.0, 0.0};
		dir[] = {0.0, 0.0, 0.0};
		pos[] = {0.0, 0.0, 0.0};
	};
};

Now in the ces6.p3d model you have roads\data\ces_hned_ca.tga texture and roads\data\ces.rvmat applied. ces.rvmat looks like this:

ambient[] = {1.0, 1.0, 1.0, 1.0};
diffuse[] = {1.0, 1.0, 1.0, 1.0};
forcedDiffuse[] = {0.0, 0.0, 0.0, 0.0};
emmisive[] = {0.0, 0.0, 0.0, 1.0};
specular[] = {1.0, 1.0, 1.0, 0.0};
specularPower = 20.0;
nextPass = "ca\roads\data\road-pass2.rvmat";
PixelShaderID = "NormalMapSpecularMap";
VertexShaderID = "NormalMap";
 
class Stage1
{
	texture = "ca\roads\data\ces_hned_nohq.paa";
	uvSource = "tex";
 
	class uvTransform
	{
		aside[] = {1.0, 0.0, 0.0};
		up[] = {0.0, 1.0, 0.0};
		dir[] = {0.0, 0.0, 0.0};
		pos[] = {0.0, 0.0, 0.0};
	};
};
 
class Stage2
{
	texture = "ca\roads\data\ces_hned_sm.paa";
	uvSource = "tex";
 
	class uvTransform
	{
		aside[] = {1.0, 0.0, 0.0};
		up[] = {0.0, 1.0, 0.0};
		dir[] = {0.0, 0.0, 0.0};
		pos[] = {0.0, 0.0, 0.0};
	};
};

In the kos6.p3d model you have roads\data\sil_kos_ca.tga texture and roads\data\sil_kos.rvmat applied. sil_kos.rvmat looks like this:

ambient[] = {1.0, 1.0, 1.0, 1.0};
diffuse[] = {1.0, 1.0, 1.0, 1.0};
forcedDiffuse[] = {0.0, 0.0, 0.0, 0.0};
emmisive[] = {0.0, 0.0, 0.0, 1.0};
specular[] = {1.0, 1.0, 1.0, 0.0};
specularPower = 20.0;
nextPass = "ca\roads\data\road-pass2.rvmat";
PixelShaderID = "NormalMapSpecularMap";
VertexShaderID = "NormalMap";
 
class Stage1
{
	texture = "ca\roads\data\sil_kos_nohq.paa";
	uvSource = "tex";
 
	class uvTransform
	{
		aside[] = {1.0, 0.0, 0.0};
		up[] = {0.0, 1.0, 0.0};
		dir[] = {0.0, 0.0, 0.0};
		pos[] = {0.0, 0.0, 0.0};
	};
};
 
class Stage2
{
	texture = "ca\roads\data\sil_kos_sm.paa";
	uvSource = "tex";
 
	class uvTransform
	{
		aside[] = {1.0, 0.0, 0.0};
		up[] = {0.0, 1.0, 0.0};
		dir[] = {0.0, 0.0, 0.0};
		pos[] = {0.0, 0.0, 0.0};
	};
};

And finally in the sil6.p3d model you have roads\data\sil_new_ara_ca.tga texture and roads\data\sil_new_ara.rvmat applied. The sil_new_ara.rvmat looks like this:

ambient[] = {1.0, 1.0, 1.0, 1.0};
diffuse[] = {1.0, 1.0, 1.0, 1.0};
forcedDiffuse[] = {0.0, 0.0, 0.0, 0.0};
emmisive[] = {0.0, 0.0, 0.0, 1.0};
specular[] = {1.0, 1.0, 1.0, 0.0};
specularPower = 20.0;
renderFlags[] = {"Road"};
nextPass = "ca\roads\data\road-pass2.rvmat";
PixelShaderID = "NormalMapSpecularMap";
VertexShaderID = "NormalMap";
 
class Stage1
{
	texture = "ca\roads\data\sil_nohq.paa";
	uvSource = "tex";
 
	class uvTransform
	{
		aside[] = {5.0, 0.0, 0.0};
		up[] = {0.0, 5.0, 0.0};
		dir[] = {0.0, 0.0, 0.0};
		pos[] = {0.0, 0.0, 0.0};
	};
};
 
class Stage2
{
	texture = "ca\roads\data\sil_new_ara_sm.paa";
	uvSource = "tex";
 
	class uvTransform
	{
		aside[] = {1.0, 0.0, 0.0};
		up[] = {0.0, 1.0, 0.0};
		dir[] = {0.0, 0.0, 0.0};
		pos[] = {0.0, 0.0, 0.0};
	};
};

All four road types have _NOHQ and _SM textures applied. Roads ces and kos are pretty much identical, they don't have the renderFlags[] = {“Road”}; in the rvmat, for reasons I have no clue about. Also asf class stage1 has this:

		aside[] = {1.0, 0.0, 0.0};
		up[] = {0.0, 1.0, 0.0};

while sil_new_ara has the following values:

		aside[] = {5.0, 0.0, 0.0};
		up[] = {0.0, 5.0, 0.0};

All this means that for our custom roads we should create _NOHQ normal maps and _SM specular maps (right?), then make RVMAT for the asf and sil roads to be pretty much identical with the stage1 difference and for ces and kos roads leave out the renderflags.

I don't claim to have any kind of experience or knowledge about this matter, this was all what I gathered from BIS example models and from the roads.pbo data directory, anyone can feel free to correct me if there is something wrong in these conclusions. Join the discussion in PMC Tactical forum topic.