adds export of normal derivation-colored mesh

src/main.cpp

@@ -1,6 +1,6 @@
 #include "my_mesh.h"
 
-#include <ctgmath>
+#include <cmath>
 #include <iostream>
 #include <fstream>
 
@@ -104,7 +104,19 @@ void stats_n_neighbors(MyMesh &mesh) {
 }
 
 
+#define MAX(a, b) ((a) > (b) ? (a) : (b))
+#define MIN(a, b) ((a) < (b) ? (a) : (b))
+static float f(int n, float h, float s, float v) {
+	float k = fmod(n + h / 60, 6);
+	return v - v * s * MAX(0, MIN(k, MIN(4 - k, 1)));
+}
+
+static OpenMesh::Vec3uc hsv_to_rgb(float h, float s, float v) {
+	return OpenMesh::Vec3uc {f(5, h, s, v) * 255, f(3, h, s, v) * 255, f(1, h, s, v) * 255};
+}
+
 void stats_normal_deviation(MyMesh &mesh) {
+	const float s = 1, v = 1, min_h = 50, max_h = 0;
 	mesh.update_normals();
 	for (const VertexHandle &vh : mesh.vertices()) {
 		MyMesh::Normal normal = mesh.normal(vh);
@@ -114,6 +126,7 @@ void stats_normal_deviation(MyMesh &mesh) {
 			if (angle > max)
 				max = angle;
 		}
+		mesh.set_color(vh, (MyMesh::Color) hsv_to_rgb(fmod(max * 360 / (max_h - min_h) + max_h, 360), s, v));
 		std::cout << max << " ";
 	}
 	std::cout << std::endl;
@@ -156,14 +169,20 @@ int main(int argc, char *argv[]) {
 	cerr << "Aire moyenne : " << area / mesh.n_faces() << endl;
 	if (argc == 3) {
 		string cmd = argv[2];
-		if (cmd == "surface")
+		if (cmd == "surface") {
 			stats_surface_area(mesh);
-		else if (cmd == "valence")
+		}
+		else if (cmd == "valence") {
 			stats_n_neighbors(mesh);
-		else if (cmd == "deviation")
+		}
+		else if (cmd == "deviation") {
 			stats_normal_deviation(mesh);
-		else if (cmd == "dièdre")
+			OpenMesh::IO::write_mesh(mesh, "out.ply",
+									 OpenMesh::IO::Options(OpenMesh::IO::Options::VertexColor));
+		}
+		else if (cmd == "dièdre") {
 			stats_dihedral_angles(mesh);
+		}
 		else {
 			cerr << "Commande inconnue : " << cmd << endl;
 			return 1;

src/my_mesh.h

@@ -10,17 +10,10 @@ using namespace OpenMesh;
 using namespace OpenMesh::Attributes;
 
 struct MyTraits : public OpenMesh::DefaultTraits {
-    // use vertex normals and vertex colors
+    VertexAttributes(OpenMesh::Attributes::Normal | OpenMesh::Attributes::Color);
-    VertexAttributes( OpenMesh::Attributes::Normal | OpenMesh::Attributes::Color );
+    HalfedgeAttributes(OpenMesh::Attributes::PrevHalfedge);
-    // store the previous halfedge
+    FaceAttributes(OpenMesh::Attributes::Normal);
-    HalfedgeAttributes( OpenMesh::Attributes::PrevHalfedge );
+    EdgeAttributes(OpenMesh::Attributes::Color);
-    // use face normals face colors
-    FaceAttributes( OpenMesh::Attributes::Normal | OpenMesh::Attributes::Color );
-    EdgeAttributes( OpenMesh::Attributes::Color );
-    // vertex thickness
-    VertexTraits{float thickness; float value; Color faceShadingColor;};
-    // edge thickness
-    EdgeTraits{float thickness;};
 };
 typedef OpenMesh::PolyMesh_ArrayKernelT<MyTraits> MyMesh;