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Calculate tangents. #11

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Calculate tangents. #11

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1 change: 1 addition & 0 deletions .gitignore
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Original file line number Diff line number Diff line change
Expand Up @@ -47,6 +47,7 @@ ExportedObj/
*.pidb.meta
*.pdb.meta
*.mdb.meta
*.meta

# Unity3D generated file on crash reports
sysinfo.txt
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8 changes: 5 additions & 3 deletions Runtime/Scripts/Fragment/FragmentData.cs
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Original file line number Diff line number Diff line change
Expand Up @@ -101,6 +101,7 @@ public FragmentData(Mesh mesh)
{
var positions = mesh.vertices;
var normals = mesh.normals;
var tangents = mesh.tangents;
var uv = mesh.uv;

this.Vertices = new List<MeshVertex>(mesh.vertexCount);
Expand All @@ -111,7 +112,7 @@ public FragmentData(Mesh mesh)
// Add mesh vertices
for (int i = 0; i < positions.Length; i++)
{
this.Vertices.Add(new MeshVertex(positions[i], normals[i], uv[i]));
this.Vertices.Add(new MeshVertex(positions[i], normals[i], tangents[i], uv[i]));
}

// Only meshes with one submesh are currently supported
Expand All @@ -137,9 +138,9 @@ public FragmentData(Mesh mesh)
/// <param name="normal">The vertex normal</param>
/// <param name="uv">The vertex UV coordinates</param>
/// <returns>Returns the index of the vertex in the cutVertices array</returns>
public void AddCutFaceVertex(Vector3 position, Vector3 normal, Vector2 uv)
public void AddCutFaceVertex(Vector3 position, Vector3 normal, Vector4 tangent, Vector2 uv)
{
var vertex = new MeshVertex(position, normal, uv);
var vertex = new MeshVertex(position, normal, tangent, uv);

// Add the vertex to both the normal mesh vertex data and the cut face vertex data
// The vertex on the cut face will have different normal/uv coordinates which are
Expand Down Expand Up @@ -290,6 +291,7 @@ public Mesh ToMesh()
{
new VertexAttributeDescriptor(VertexAttribute.Position, VertexAttributeFormat.Float32, 3),
new VertexAttributeDescriptor(VertexAttribute.Normal, VertexAttributeFormat.Float32, 3),
new VertexAttributeDescriptor(VertexAttribute.Tangent, VertexAttributeFormat.Float32, 4),
new VertexAttributeDescriptor(VertexAttribute.TexCoord0, VertexAttributeFormat.Float32, 2),
};

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13 changes: 9 additions & 4 deletions Runtime/Scripts/Fragment/MeshSlicer.cs
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Expand Up @@ -275,11 +275,16 @@ private static void SplitTriangle(int v1_idx,
var uv13 = v1.uv + s13 * (v3.uv - v1.uv);
var uv23 = v2.uv + s23 * (v3.uv - v2.uv);

var tang13 = Vector4.Lerp(v2.tangent, v3.tangent, s13).normalized;
tang13.w = Mathf.Lerp(v2.tangent.w, v3.tangent.w, s13);
var tang23 = Vector4.Lerp(v2.tangent, v3.tangent, s23).normalized;
tang23.w = Mathf.Lerp(v2.tangent.w, v3.tangent.w, s23);
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not sure if this is correct, I was inspired by http://answers.unity.com/comments/485110/view.html


// Add vertices/normals/uv for the intersection points to each mesh
topSlice.AddCutFaceVertex(v13, norm13, uv13);
topSlice.AddCutFaceVertex(v23, norm23, uv23);
bottomSlice.AddCutFaceVertex(v13, norm13, uv13);
bottomSlice.AddCutFaceVertex(v23, norm23, uv23);
topSlice.AddCutFaceVertex(v13, norm13, tang13, uv13);
topSlice.AddCutFaceVertex(v23, norm23, tang13, uv23);
bottomSlice.AddCutFaceVertex(v13, norm13, tang23, uv13);
bottomSlice.AddCutFaceVertex(v23, norm23, tang23, uv23);

// Indices for the intersection vertices (for the original mesh data)
int index13_A = topSlice.Vertices.Count - 2;
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11 changes: 11 additions & 0 deletions Runtime/Scripts/Fragment/MeshVertex.cs
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Expand Up @@ -8,19 +8,30 @@ public struct MeshVertex
{
public Vector3 position;
public Vector3 normal;
public Vector4 tangent;
public Vector2 uv;

public MeshVertex(Vector3 position)
{
this.position = position;
this.normal = Vector3.zero;
this.tangent = Vector4.zero;
this.uv = Vector2.zero;
}

public MeshVertex(Vector3 position, Vector3 normal, Vector2 uv)
{
this.position = position;
this.normal = normal;
this.tangent = Vector4.zero;
this.uv = uv;
}

public MeshVertex(Vector3 position, Vector3 normal, Vector4 tangents, Vector2 uv)
{
this.position = position;
this.normal = normal;
this.tangent = tangents;
this.uv = uv;
}

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