private void GetVertInfo(OBJFile file, int vertexIndex, out Vector3 o_pos, out Vector4 o_colour, out Vector2 o_texCoord, out Vector3?o_normal)
{
var vertex = file.Verts[vertexIndex];
var objPos = file.Positions[vertex.PositionIndex - 1];
o_pos = objPos;
var objColour = file.Colours[vertex.PositionIndex - 1];
o_colour = objColour;
if (vertex.TexCoordIndex > 0)
{
var objTexCoord = file.TexCoords[vertex.TexCoordIndex - 1];
o_texCoord = new Vector2(objTexCoord.X, 1.0f - objTexCoord.Y);
}
else
{
o_texCoord = new Vector2(0.5f, 0.5f);
}
if (vertex.NormalIndex > 0)
{
var objNormal = file.Normals[vertex.NormalIndex - 1];
o_normal = objNormal;
o_normal.Value.Normalize();
}
else
{
o_normal = null;
}
}
private void Load(IFileStore store)
{
// Load
var objFile = new OBJFile();
using (var reader = store.OpenTextFile(m_path))
{
objFile.Parse(reader);
}
// Interpret
var dir = AssetPath.GetDirectoryName(m_path);
m_materialFile = AssetPath.Combine(dir, objFile.MTLLib);
m_groups = new List <Group>();
m_groupLookup = new Dictionary <string, int>();
foreach (var objGroup in objFile.Groups)
{
// Skip empty groups
if (objGroup.Faces.Count == 0)
{
continue;
}
// Load geometry
Geometry geometry = new Geometry(Primitive.Triangles);
for (int i = 0; i < objGroup.Faces.Count; ++i)
{
var objFace = objGroup.Faces[i];
if (objFace.VertexCount >= 3)
{
Vector3 posA, posB, posC;
Vector4 colourA, colourB, colourC;
Vector3?normA, normB, normC;
Vector2 texCoordA, texCoordB, texCoordC;
GetVertInfo(objFile, objFace.FirstVertex, out posA, out colourA, out texCoordA, out normA);
GetVertInfo(objFile, objFace.FirstVertex + 1, out posB, out colourB, out texCoordB, out normB);
GetVertInfo(objFile, objFace.FirstVertex + 2, out posC, out colourC, out texCoordC, out normC);
Vector3 faceNormal, faceTangent;
MathUtils.GenerateNormalAndTangent(
posA, posB, posC,
texCoordA, texCoordB, texCoordC,
out faceNormal, out faceTangent
);
// Add the verts
int firstVertIndex = geometry.VertexCount;
geometry.AddVertex(posA, normA.HasValue ? normA.Value : faceNormal, faceTangent, texCoordA, colourA);
geometry.AddVertex(posB, normB.HasValue ? normB.Value : faceNormal, faceTangent, texCoordB, colourB);
geometry.AddVertex(posC, normC.HasValue ? normC.Value : faceNormal, faceTangent, texCoordC, colourC);
for (int j = 3; j < objFace.VertexCount; ++j)
{
Vector3 posN;
Vector4 colourN;
Vector3?normN;
Vector2 texCoordN;
GetVertInfo(objFile, objFace.FirstVertex + j, out posN, out colourN, out texCoordN, out normN);
geometry.AddVertex(posN, normN.HasValue ? normN.Value : faceNormal, faceTangent, texCoordN, colourN);
}
// Add the indexes
for (int k = 2; k < objFace.VertexCount; ++k)
{
geometry.AddIndex(firstVertIndex);
geometry.AddIndex(firstVertIndex + k - 1);
geometry.AddIndex(firstVertIndex + k);
}
}
}
geometry.Rebuild();
// Build shadow geometry
var shadowGeometry = new Geometry(Primitive.Triangles);
shadowGeometry.AddShadowGeometry(geometry, ref Matrix4.Identity);
shadowGeometry.Rebuild();
// Prepare the group
var group = new Group();
group.Name = objGroup.Name;
group.MaterialName = objGroup.MaterialName;
group.Geometry = geometry;
group.ShadowGeometry = shadowGeometry;
m_groupLookup.Add(group.Name, m_groups.Count);
m_groups.Add(group);
}
}