From 4ad94bbb924b05317fd0d89b0debce9b8c871563 Mon Sep 17 00:00:00 2001
From: kovacsv <viktorkovacs@gmail.com>
Date: Wed, 27 Dec 2023 07:53:41 +0100
Subject: [PATCH] Export lines to obj.

---
 source/engine/export/exporterobj.js | 32 +++++++++++++++------
 test/tests/exportimport_test.js     | 44 +++++++++++++++++++++++++++++
 2 files changed, 68 insertions(+), 8 deletions(-)

diff --git a/source/engine/export/exporterobj.js b/source/engine/export/exporterobj.js
index ea23f3d..6a27efb 100644
--- a/source/engine/export/exporterobj.js
+++ b/source/engine/export/exporterobj.js
@@ -90,14 +90,6 @@ export class ExporterObj extends ExporterBase
                 let n0 = triangle.n0 + normalOffset + 1;
                 let n1 = triangle.n1 + normalOffset + 1;
                 let n2 = triangle.n2 + normalOffset + 1;
-                if (triangle.mat !== null) {
-                    let material = exporterModel.GetMaterial (triangle.mat);
-                    let materialName = this.GetExportedMaterialName (material.name);
-                    if (materialName !== usedMaterialName) {
-                        objWriter.WriteArrayLine (['usemtl', materialName]);
-                        usedMaterialName = materialName;
-                    }
-                }
                 let u0 = '';
                 let u1 = '';
                 let u2 = '';
@@ -106,8 +98,32 @@ export class ExporterObj extends ExporterBase
                     u1 = triangle.u1 + uvOffset + 1;
                     u2 = triangle.u2 + uvOffset + 1;
                 }
+                if (triangle.mat !== null) {
+                    let material = exporterModel.GetMaterial (triangle.mat);
+                    let materialName = this.GetExportedMaterialName (material.name);
+                    if (materialName !== usedMaterialName) {
+                        objWriter.WriteArrayLine (['usemtl', materialName]);
+                        usedMaterialName = materialName;
+                    }
+                }
                 objWriter.WriteArrayLine (['f', [v0, u0, n0].join ('/'), [v1, u1, n1].join ('/'), [v2, u2, n2].join ('/')]);
             }
+            for (let lineIndex = 0; lineIndex < mesh.LineCount (); lineIndex++) {
+                let line = mesh.GetLine (lineIndex);
+                let vertexIndices = [];
+                for (let vertexIndex = 0; vertexIndex < line.vertices.length; vertexIndex++) {
+                    vertexIndices.push (line.vertices[vertexIndex] + vertexOffset + 1);
+                }
+                if (line.mat !== null) {
+                    let material = exporterModel.GetMaterial (line.mat);
+                    let materialName = this.GetExportedMaterialName (material.name);
+                    if (materialName !== usedMaterialName) {
+                        objWriter.WriteArrayLine (['usemtl', materialName]);
+                        usedMaterialName = materialName;
+                    }
+                }
+                objWriter.WriteArrayLine (['l', vertexIndices.join (' ')]);
+            }
             vertexOffset += mesh.VertexCount ();
             normalOffset += mesh.NormalCount ();
             uvOffset += mesh.TextureUVCount ();
diff --git a/test/tests/exportimport_test.js b/test/tests/exportimport_test.js
index f9bbb08..d20cd05 100644
--- a/test/tests/exportimport_test.js
+++ b/test/tests/exportimport_test.js
@@ -18,6 +18,7 @@ function CreateTestModel ()
 
     let phongMaterial = new OV.PhongMaterial ();
     phongMaterial.name = 'Phong Material';
+    phongMaterial.color = new OV.RGBColor (0, 0, 0);
     phongMaterial.emissive = new OV.RGBColor (1, 1, 1);
     phongMaterial.opacity = 0.1;
     phongMaterial.transparent = true;
@@ -30,6 +31,7 @@ function CreateTestModel ()
 
     let phongMaterialTexture = new OV.PhongMaterial ();
     phongMaterialTexture.name = 'Phong Material With Texture';
+    phongMaterialTexture.color = new OV.RGBColor (0, 0, 0);
     phongMaterialTexture.emissive = new OV.RGBColor (1, 1, 1);
     phongMaterialTexture.opacity = 0.1;
     phongMaterialTexture.transparent = true;
@@ -47,6 +49,7 @@ function CreateTestModel ()
 
     let physicalMaterialTexture = new OV.PhysicalMaterial ();
     physicalMaterialTexture.name = 'Phong Material With Texture';
+    physicalMaterialTexture.color = new OV.RGBColor (0, 0, 0);
     physicalMaterialTexture.emissive = new OV.RGBColor (1, 1, 1);
     physicalMaterialTexture.opacity = 0.1;
     physicalMaterialTexture.transparent = true;
@@ -108,6 +111,39 @@ function CreateTestModel ()
     return model;
 }
 
+function CreateTestModelWithLines ()
+{
+    let model = new OV.Model ();
+
+    let phongMaterial = new OV.PhongMaterial ();
+    phongMaterial.name = 'Material';
+    phongMaterial.color = new OV.RGBColor (0, 0, 0);
+    model.AddMaterial (phongMaterial);
+
+    let meshOnly = new OV.Mesh ();
+    meshOnly.SetName ('Mesh Only');
+    meshOnly.AddVertex (new OV.Coord3D (0.0, 0.0, 0.0));
+    meshOnly.AddVertex (new OV.Coord3D (1.0, 0.0, 0.0));
+    meshOnly.AddVertex (new OV.Coord3D (0.0, 1.0, 0.0));
+    meshOnly.AddTriangle (new OV.Triangle (0, 1, 2).SetMaterial (0));
+    model.AddMeshToRootNode (meshOnly);
+
+    let meshAndLines = new OV.Mesh ();
+    meshAndLines.SetName ('Meshes and Lines');
+    meshAndLines.AddVertex (new OV.Coord3D (0.0, 0.0, 0.0));
+    meshAndLines.AddVertex (new OV.Coord3D (1.0, 0.0, 0.0));
+    meshAndLines.AddVertex (new OV.Coord3D (0.0, 1.0, 0.0));
+    meshAndLines.AddTriangle (new OV.Triangle (0, 1, 2).SetMaterial (0));
+    meshAndLines.AddVertex (new OV.Coord3D (0.0, 0.0, 1.0));
+    meshAndLines.AddVertex (new OV.Coord3D (1.0, 0.0, 1.0));
+    meshAndLines.AddVertex (new OV.Coord3D (0.0, 1.0, 1.0));
+    meshAndLines.AddLine (new OV.Line ([3, 4, 5]).SetMaterial (0));
+    model.AddMeshToRootNode (meshAndLines);
+
+    OV.FinalizeModel (model);
+    return model;
+}
+
 function ExportImport (model, format, extension, onReady)
 {
     let exporter = new OV.Exporter ();
@@ -172,6 +208,14 @@ describe ('Export-Import Test', function () {
         });
     });
 
+    it ('Export-Import Obj with Lines', function (done) {
+        let model = CreateTestModelWithLines ();
+        ExportImport (model, OV.FileFormat.Text, 'obj', (model2) => {
+            CheckModel (model, model2);
+            done ();
+        });
+    });
+
     it ('Export-Import Stl Ascii', function (done) {
         let model = CreateTestModel ();
         ExportImport (model, OV.FileFormat.Text, 'stl', (model2) => {