Moved normal/tangents generation to submeshes

Former-commit-id: d043284a1a5810b429cc76d8bc071010985a523b

src/Nazara/Utility/SubMesh.cpp

@@ -7,6 +7,8 @@
 #include <Nazara/Core/String.hpp>
 #include <Nazara/Utility/Config.hpp>
 #include <Nazara/Utility/Mesh.hpp>
+#include <Nazara/Utility/TriangleIterator.hpp>
+#include <Nazara/Utility/VertexMapper.hpp>
 #include <stdexcept>
 #include <Nazara/Utility/Debug.hpp>
 
@@ -19,6 +21,126 @@ m_matIndex(0)
 
 NzSubMesh::~NzSubMesh() = default;
 
+void NzSubMesh::GenerateNormals()
+{
+	NzVertexMapper mapper1(this);
+	unsigned int vertexCount = mapper1.GetVertexCount();
+	for (unsigned int i = 0; i < vertexCount; ++i)
+		mapper1.SetNormal(i, NzVector3f::Zero());
+
+	mapper1.Unmap();
+
+	NzTriangleIterator iterator(this);
+	do
+	{
+		NzVector3f pos0 = iterator.GetPosition(0);
+
+		NzVector3f dv[2];
+		dv[0] = iterator.GetPosition(1) - pos0;
+		dv[1] = iterator.GetPosition(2) - pos0;
+
+		NzVector3f normal = dv[0].CrossProduct(dv[1]);
+
+		for (unsigned int i = 0; i < 3; ++i)
+			iterator.SetNormal(i, iterator.GetNormal(i) + normal);
+	}
+	while (iterator.Advance());
+
+	NzVertexMapper mapper2(this);
+	for (unsigned int i = 0; i < vertexCount; ++i)
+		mapper2.SetNormal(i, NzVector3f::Normalize(mapper2.GetNormal(i)));
+}
+
+void NzSubMesh::GenerateNormalsAndTangents()
+{
+	NzVertexMapper mapper1(this);
+	unsigned int vertexCount = mapper1.GetVertexCount();
+	for (unsigned int i = 0; i < vertexCount; ++i)
+	{
+		mapper1.SetNormal(i, NzVector3f::Zero());
+		mapper1.SetTangent(i, NzVector3f::Zero());
+	}
+
+	mapper1.Unmap();
+
+	NzTriangleIterator iterator(this);
+	do
+	{
+		NzVector3f pos0 = iterator.GetPosition(0);
+		NzVector2f uv0 = iterator.GetTexCoord(0);
+
+		NzVector3f dv[2];
+		dv[0] = iterator.GetPosition(1) - pos0;
+		dv[1] = iterator.GetPosition(2) - pos0;
+
+		NzVector3f normal = dv[0].CrossProduct(dv[1]);
+
+		NzVector2f duv[2];
+		duv[0] = iterator.GetTexCoord(1) - uv0;
+		duv[1] = iterator.GetTexCoord(2) - uv0;
+
+		float coef = 1.f / (duv[0].x*duv[1].y - duv[1].x*duv[0].y);
+
+		NzVector3f tangent;
+		tangent.x = coef * (dv[0].x*duv[1].y + dv[1].x*(-duv[0].y));
+		tangent.y = coef * (dv[0].y*duv[1].y + dv[1].y*(-duv[0].y));
+		tangent.z = coef * (dv[0].z*duv[1].y + dv[1].z*(-duv[0].y));
+
+		for (unsigned int i = 0; i < 3; ++i)
+		{
+			iterator.SetNormal(i, iterator.GetNormal(i) + normal);
+			iterator.SetTangent(i, iterator.GetTangent(i) + tangent);
+		}
+	}
+	while (iterator.Advance());
+
+	NzVertexMapper mapper2(this);
+	for (unsigned int i = 0; i < vertexCount; ++i)
+	{
+		mapper2.SetNormal(i, NzVector3f::Normalize(mapper2.GetNormal(i)));
+		mapper2.SetTangent(i, NzVector3f::Normalize(mapper2.GetTangent(i)));
+	}
+}
+
+void NzSubMesh::GenerateTangents()
+{
+	NzTriangleIterator iterator(this);
+	do
+	{
+		NzVector3f pos0 = iterator.GetPosition(0);
+		NzVector2f uv0 = iterator.GetTexCoord(0);
+
+		NzVector3f dv[2];
+		dv[0] = iterator.GetPosition(1) - pos0;
+		dv[1] = iterator.GetPosition(2) - pos0;
+
+		NzVector2f duv[2];
+		duv[0] = iterator.GetTexCoord(1) - uv0;
+		duv[1] = iterator.GetTexCoord(2) - uv0;
+
+		float ds[2];
+		ds[0] = iterator.GetTexCoord(1).x - uv0.x;
+		ds[1] = iterator.GetTexCoord(2).x - uv0.x;
+
+		NzVector3f ppt;
+		ppt.x = ds[0]*dv[1].x - dv[0].x*ds[1];
+		ppt.y = ds[0]*dv[1].y - dv[0].y*ds[1];
+		ppt.z = ds[0]*dv[1].z - dv[0].z*ds[1];
+		ppt.Normalize();
+
+		for (unsigned int i = 0; i < 3; ++i)
+		{
+			NzVector3f normal = iterator.GetNormal(i);
+			float d = ppt.DotProduct(normal);
+
+			NzVector3f tangent = ppt - (d * normal);
+
+			iterator.SetTangent(i, tangent);
+		}
+	}
+	while (iterator.Advance());
+}
+
 const NzMesh* NzSubMesh::GetParent() const
 {
 	return m_parent;