Export materials file for gcode toolpaths when exported to obj file

1 files changed, 45 insertions, 2 deletions

diff --git a/src/slic3r/GUI/3DScene.cpp b/src/slic3r/GUI/3DScene.cpp
index 88a7edee6..d29e41d35 100644
--- a/src/slic3r/GUI/3DScene.cpp
+++ b/src/slic3r/GUI/3DScene.cpp
@@ -886,14 +886,51 @@ void GLVolumeCollection::export_toolpaths_to_obj(const char* filename) const
     if (!has_toolpaths_to_export())
         return;
 
-    FILE* fp = boost::nowide::fopen(filename, "w");
+    // collect color information to generate materials
+    std::set<std::array<float, 4>> colors;
+    for (const GLVolume* volume : this->volumes)
+    {
+        if (!can_export_to_obj(*volume))
+            continue;
+
+        std::array<float, 4> color;
+        ::memcpy((void*)color.data(), (const void*)volume->color, 4 * sizeof(float));
+        colors.insert(color);
+    }
+
+    // save materials file
+    boost::filesystem::path mat_filename(filename);
+    mat_filename.replace_extension("mtl");
+    FILE* fp = boost::nowide::fopen(mat_filename.string().c_str(), "w");
+    if (fp == nullptr) {
+        BOOST_LOG_TRIVIAL(error) << "GLVolumeCollection::export_toolpaths_to_obj: Couldn't open " << mat_filename.string().c_str() << " for writing";
+        return;
+    }
+
+    fprintf(fp, "# G-Code Toolpaths Materials\n");
+    fprintf(fp, "# Generated by %s based on Slic3r\n", SLIC3R_BUILD_ID);
+
+    unsigned int colors_count = 1;
+    for (const std::array<float, 4>& color : colors)
+    {        
+        fprintf(fp, "\nnewmtl material_%d\n", colors_count++);
+        fprintf(fp, "Ka 1 1 1\n");
+        fprintf(fp, "Kd %f %f %f\n", color[0], color[1], color[2]);
+        fprintf(fp, "Ks 0 0 0\n");
+    }
+
+    fclose(fp);
+
+    // save geometry file
+    fp = boost::nowide::fopen(filename, "w");
     if (fp == nullptr) {
         BOOST_LOG_TRIVIAL(error) << "GLVolumeCollection::export_toolpaths_to_obj: Couldn't open " << filename << " for writing";
         return;
     }
 
     fprintf(fp, "# G-Code Toolpaths\n");
-    fprintf(fp, "# Generated by %s based on Slic3r\n\n", SLIC3R_BUILD_ID);
+    fprintf(fp, "# Generated by %s based on Slic3r\n", SLIC3R_BUILD_ID);
+    fprintf(fp, "\nmtllib ./%s\n", mat_filename.filename().string().c_str());
 
     unsigned int vertices_count = 0;
     unsigned int volumes_count = 0;
@@ -987,6 +1024,12 @@ void GLVolumeCollection::export_toolpaths_to_obj(const char* filename) const
             fprintf(fp, "vn %f %f %f\n", vertices_and_normals_interleaved[i + 0], vertices_and_normals_interleaved[i + 1], vertices_and_normals_interleaved[i + 2]);
         }
 
+        std::array<float, 4> color;
+        ::memcpy((void*)color.data(), (const void*)volume->color, 4 * sizeof(float));
+        colors.insert(color);
+        fprintf(fp, "\n# material volume %d\n", volumes_count);
+        fprintf(fp, "usemtl material_%lld\n", 1 + std::distance(colors.begin(), colors.find(color)));
+
         fprintf(fp, "\n# triangular facets volume %d\n", volumes_count);
         for (unsigned int i = 0; i < triangle_indices.size(); i += 3)
         {