The new kernel is still far from finished - probably A7 - so the suggested lightmap importer would be the way to go.

Yes, you just need the vertex buffer, and just need to overwite the two floats u2/v2. This is the pseudocode:

Code:

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LPD3DXMESH pMesh = (LPD3DXMESH) ent_mesh(entity);
BYTEPTR pVB;
pMesh->LockVertexBuffer(0,&pVB);
for (int i=0; i<numverts; i++)
{
  VERTEX_TLSHADED *v = ((VERTEX_TLSHADED*)pVB) + i; // see vertex format in "shader" 
  v->u2 = lightmap_u2[i];
  v->v2 = lightmap_v2[i];
}
pMesh->UnlockVertexBuffer();

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