Added mesh generation of normals and tangents

Former-commit-id: 42b29acf5701b19156d6966b402baf11c87f3476

include/Nazara/Utility/Mesh.hpp

@@ -55,6 +55,10 @@ class NAZARA_API NzMesh : public NzResource, NzResourceListener
 		bool CreateStatic();
 		void Destroy();
 
+		void GenerateNormals();
+		void GenerateNormalsAndTangents();
+		void GenerateTangents();
+
 		const NzAxisAlignedBox& GetAABB() const;
 		NzString GetAnimation() const;
 		nzAnimationType GetAnimationType() const;

src/Nazara/Utility/Mesh.cpp

@@ -11,6 +11,8 @@
 #include <Nazara/Utility/SkeletalMesh.hpp>
 #include <Nazara/Utility/Skeleton.hpp>
 #include <Nazara/Utility/SubMesh.hpp>
+#include <Nazara/Utility/TriangleIterator.hpp>
+#include <Nazara/Utility/VertexMapper.hpp>
 #include <cstring>
 #include <deque>
 #include <map>
@@ -262,6 +264,159 @@ void NzMesh::Destroy()
 	}
 }
 
+void NzMesh::GenerateNormals()
+{
+	#if NAZARA_UTILITY_SAFE
+	if (!m_impl)
+	{
+		NazaraError("Mesh not created");
+		return;
+	}
+	#endif
+
+	for (NzSubMesh* subMesh : m_impl->subMeshes)
+	{
+		NzVertexMapper mapper1(subMesh);
+		unsigned int vertexCount = mapper1.GetVertexCount();
+		for (unsigned int i = 0; i < vertexCount; ++i)
+			mapper1.SetNormal(i, NzVector3f::Zero());
+
+		mapper1.Unmap();
+
+		NzTriangleIterator iterator(subMesh);
+		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(subMesh);
+		for (unsigned int i = 0; i < vertexCount; ++i)
+			mapper2.SetNormal(i, NzVector3f::Normalize(mapper2.GetNormal(i)));
+	}
+}
+
+void NzMesh::GenerateNormalsAndTangents()
+{
+	#if NAZARA_UTILITY_SAFE
+	if (!m_impl)
+	{
+		NazaraError("Mesh not created");
+		return;
+	}
+	#endif
+
+	for (NzSubMesh* subMesh : m_impl->subMeshes)
+	{
+		NzVertexMapper mapper1(subMesh);
+		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(subMesh);
+		do
+		{
+			NzVector3f pos0 = iterator.GetPosition(0);
+			NzVector2f uv0 = iterator.GetTexCoords(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.GetTexCoords(1) - uv0;
+			duv[1] = iterator.GetTexCoords(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(subMesh);
+		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 NzMesh::GenerateTangents()
+{
+	#if NAZARA_UTILITY_SAFE
+	if (!m_impl)
+	{
+		NazaraError("Mesh not created");
+		return;
+	}
+	#endif
+
+	for (NzSubMesh* subMesh : m_impl->subMeshes)
+	{
+		NzTriangleIterator iterator(subMesh);
+		do
+		{
+			NzVector3f pos0 = iterator.GetPosition(0);
+			NzVector2f uv0 = iterator.GetTexCoords(0);
+
+			NzVector3f dv[2];
+			dv[0] = iterator.GetPosition(1) - pos0;
+			dv[1] = iterator.GetPosition(2) - pos0;
+
+			NzVector2f duv[2];
+			duv[0] = iterator.GetTexCoords(1) - uv0;
+			duv[1] = iterator.GetTexCoords(2) - uv0;
+
+			float ds[2];
+			ds[0] = iterator.GetTexCoords(1).x - uv0.x;
+			ds[1] = iterator.GetTexCoords(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 NzAxisAlignedBox& NzMesh::GetAABB() const
 {
 	#if NAZARA_UTILITY_SAFE