// Static API
// Rewrites data in mesh to ensure that it only contains valid particle quads.
internal static void FilterMesh(Mesh mesh, WarningCallback callback)
{
ParticleMesh src = ParticleMesh.FromMesh(mesh);
ParticleMesh dst = new ParticleMesh();
// ClassifyQuad wants at least 6 indices (2 triangles) to examine
int limit = src.TriangleCount - 6;
int iiVert = 0;
while (iiVert < limit)
{
switch (src.ClassifyQuad(iiVert, callback))
{
case ParticleMesh.QuadType.FullParticle:
dst.AppendQuad(src, iiVert);
iiVert += 6;
break;
case ParticleMesh.QuadType.Degenerate:
iiVert += 6;
break;
case ParticleMesh.QuadType.LatterHalfParticle:
iiVert += 3;
break;
case ParticleMesh.QuadType.Unknown:
default:
iiVert += 1;
break;
}
}
dst.CopyToMesh(mesh);
}
// iiVert is an index to an index to a vert (an index into m_triangles)
// iiVert must be at least 6 verts from the end of the mesh.
internal QuadType ClassifyQuad(int iiVert, WarningCallback callback)
{
if (iiVert + 6 > m_triangles.Count)
{
Debug.Assert(false, "Invalid ClassifyQuad {0}", m_sourceMesh);
return(QuadType.Unknown);
}
int i = iiVert;
int v = m_triangles[i];
// AppendQuad assumes that the first index of the quad is the lowest index.
// All of these "+n" offsets should be positive.
if ((m_triangles[i] == v &&
m_triangles[i + 1] == v + 1 &&
m_triangles[i + 2] == v + 3 &&
m_triangles[i + 3] == v + 0 &&
m_triangles[i + 4] == v + 3 &&
m_triangles[i + 5] == v + 2) ||
(m_triangles[i] == v &&
m_triangles[i + 1] == v + 1 &&
m_triangles[i + 2] == v + 2 &&
m_triangles[i + 3] == v + 0 &&
m_triangles[i + 4] == v + 2 &&
m_triangles[i + 5] == v + 3))
{
if (m_lastMod == null || (v % 4) != m_lastMod.Value)
{
// if (m_lastMod != null) {
// Debug.LogFormat(
// "At {0}: changing mod to {1}\n{2} {3} {4} {5} {6} {7}",
// iiVert, v % 4,
// m_triangles[i ], m_triangles[i+1], m_triangles[i+2],
// m_triangles[i+3], m_triangles[i+4], m_triangles[i+5]);
// }
m_lastMod = (v % 4);
}
return(QuadType.FullParticle);
}
else if (m_triangles[i] == v &&
m_triangles[i + 1] == v &&
m_triangles[i + 2] == v &&
m_triangles[i + 3] == v &&
m_triangles[i + 4] == v &&
m_triangles[i + 5] == v)
{
// Seems to be produced by either TB or FBX export
// Debug.LogFormat("At {0}: degenerate quad", iiVert);
return(QuadType.Degenerate);
}
else if ((m_triangles[i] == v &&
m_triangles[i + 1] == v + 3 &&
m_triangles[i + 2] == v + 2) ||
(m_triangles[i] == v &&
m_triangles[i + 1] == v + 2 &&
m_triangles[i + 2] == v + 3))
{
// Will be produced by Unity splitting the particle mesh up
// Debug.LogFormat("At {0}: half-particle", iiVert);
return(QuadType.LatterHalfParticle);
}
else
{
if (m_bNoisy)
{
m_bNoisy = false;
if (callback != null)
{
callback(string.Format(
"Found unexpected index sequence @ {0}: {1} {2} {3} {4} {5} {6} {7} {8} {9}",
iiVert,
m_triangles[i], m_triangles[i + 1], m_triangles[i + 2],
m_triangles[i + 3], m_triangles[i + 4], m_triangles[i + 5],
m_triangles[i + 9], m_triangles[i + 10], m_triangles[i + 11]));
}
}
return(QuadType.Unknown);
}
}
