private static Vector3[] ExtractBuffer3(vts.Mesh m, int attributeIndex)
{
var a = m.attributes[attributeIndex];
if (!a.enable)
{
return(null);
}
Debug.Assert(a.components == 3);
uint typeSize = Util.GpuTypeSize(a.type);
Vector3[] r = new Vector3[m.verticesCount];
int stride = (int)(a.stride == 0 ? typeSize * a.components : a.stride);
int start = (int)a.offset;
for (int i = 0; i < m.verticesCount; i++)
{
r[i] = new Vector3(
ExtractFloat(m, start + i * stride + 0 * (int)typeSize, a.type, a.normalized),
ExtractFloat(m, start + i * stride + 1 * (int)typeSize, a.type, a.normalized),
ExtractFloat(m, start + i * stride + 2 * (int)typeSize, a.type, a.normalized)
);
}
return(r);
}
private void LoadLinesIndices(vts.Mesh m)
{
topology = MeshTopology.Lines;
if (m.indices != null)
{
indices = Array.ConvertAll(m.indices, Convert.ToInt32);
}
else
{
indices = new int[m.verticesCount];
for (int i = 0; i < m.verticesCount; i++)
{
indices[i] = i;
}
}
}
private static float ExtractFloat(vts.Mesh m, int byteOffset, GpuType type, bool normalized)
{
switch (type)
{
case GpuType.Float:
Debug.Assert(!normalized);
return(BitConverter.ToSingle(m.vertices, byteOffset));
case GpuType.UnsignedShort:
Debug.Assert(normalized);
return(BitConverter.ToUInt16(m.vertices, byteOffset) / 65535.0f);
default:
throw new VtsException(-17, "Unsupported gpu type");
}
}
private void LoadTrianglesIndices(vts.Mesh m)
{
topology = MeshTopology.Triangles;
if (m.indices != null)
{
indices = Array.ConvertAll(m.indices, Convert.ToInt32);
}
else
{
indices = new int[m.verticesCount];
for (int i = 0; i < m.verticesCount; i += 3)
{
indices[i + 0] = i + 0;
indices[i + 1] = i + 1;
indices[i + 2] = i + 2;
}
}
}
public VtsMesh(vts.Mesh m)
{
// assume that attribute 0 is vertex positions
vertices = ExtractBuffer3(m, 0);
// assume that attribute 1 is internal texture coordinates (used with textures that are packed with the mesh)
uv0 = ExtractBuffer2(m, 1);
// assume that attribute 2 is external texture coordinates (used with textures that come from bound layers)
uv1 = ExtractBuffer2(m, 2);
// indices
switch (m.faceMode)
{
case FaceMode.Triangles:
LoadTrianglesIndices(m);
break;
case FaceMode.Lines:
LoadLinesIndices(m);
break;
default:
throw new VtsException(-19, "Unsupported mesh face mode");
}
}
public static System.Object LoadMesh(vts.Mesh m)
{
return(new VtsMesh(m));
}
