From 36bc8e1b5c70a5849961a71095709c434f3992c4 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Th=C3=A9ophile=20Bastian?= <contact@tobast.fr>
Date: Tue, 13 Feb 2018 14:47:34 +0100
Subject: [PATCH] Use normals for implicit surfaces

---
 Makefile              |  2 +-
 MarchingCubes.cpp     | 16 +---------------
 render/GlutRender.cpp | 20 ++++++++++++++++++++
 3 files changed, 22 insertions(+), 16 deletions(-)

diff --git a/Makefile b/Makefile
index 7a7570b..21818ce 100644
--- a/Makefile
+++ b/Makefile
@@ -1,5 +1,5 @@
 CXX=g++
-CXXFLAGS=-Wall -Wextra -O2 -std=c++14
+CXXFLAGS=$(ADD_FLAGS) -Wall -Wextra -O2 -std=c++14
 CXXLIBS=-lGL -lGLU -lglut
 
 # In `TARGET`, list the names of the `main_[stuff].cpp` you'd like to compile
diff --git a/MarchingCubes.cpp b/MarchingCubes.cpp
index ea91bc1..3fbd372 100644
--- a/MarchingCubes.cpp
+++ b/MarchingCubes.cpp
@@ -89,22 +89,8 @@ bool MarchingCubes::march_at(double x, double y, double z, Mesh& output) {
 
         size_t vert_ids[3];
         for(int i=0; i < 3; ++i) {
-#ifdef DEBUG_DISPLAY_NORMAL
-            Point locVert = verts[i] + surface.getCenter();
             Point normal = surface.normal_at(verts[i]);
-            Point outwards = locVert + normal;
-            Point inwards = locVert + ((-0.2) * normal);
-            glBegin(GL_LINES);
-                glColor3f(1., 0., 0.);
-                glVertex3f(locVert[0], locVert[1], locVert[2]);
-                glVertex3f(outwards[0], outwards[1], outwards[2]);
-                glColor3f(0., 0., 1.);
-                glVertex3f(locVert[0], locVert[1], locVert[2]);
-                glVertex3f(inwards[0], inwards[1], inwards[2]);
-            glEnd();
-#endif // DEBUG_DISPLAY_NORMAL
-
-            vert_ids[i] = output.add_vertice(verts[i]);
+            vert_ids[i] = output.add_vertice(verts[i], normal);
         }
 
         for(int i=0; i < 3; ++i) {
diff --git a/render/GlutRender.cpp b/render/GlutRender.cpp
index 4e8742c..2310474 100644
--- a/render/GlutRender.cpp
+++ b/render/GlutRender.cpp
@@ -83,6 +83,26 @@ void GlutRender::display_mesh(Mesh& mesh) const {
 
     const std::vector<Point>& points = mesh.get_vertices();
 
+#ifdef DEBUG_DISPLAY_NORMAL
+
+    glBegin(GL_LINES);
+    for(size_t vert_id=0; vert_id < points.size(); ++vert_id) {
+        const Point& pt = points[vert_id];
+        Point normal = mesh.get_normal(vert_id);
+        Point locVert = pt + mesh.get_center();
+        Point outwards = locVert + normal;
+        Point inwards = locVert + ((-0.2) * normal);
+        glColor3f(1., 0., 0.);
+        glVertex3f(locVert[0], locVert[1], locVert[2]);
+        glVertex3f(outwards[0], outwards[1], outwards[2]);
+        glColor3f(0., 0., 1.);
+        glVertex3f(locVert[0], locVert[1], locVert[2]);
+        glVertex3f(inwards[0], inwards[1], inwards[2]);
+    }
+    glEnd();
+#endif // DEBUG_DISPLAY_NORMAL
+
+
     glBegin(GL_TRIANGLES);
     for(const Face& face: mesh.get_faces()) {
         Point p0 = face.pt(0, points) + mesh_center,