From 39150096d8bcf925b14c4304e660e19a6df76fa5 Mon Sep 17 00:00:00 2001
From: Aras Pranckevicius <aras@nesnausk.org>
Date: Mon, 13 May 2024 11:45:20 +0300
Subject: [PATCH] Fix #121720: OBJ does not import some curves properly

If a curve was not using U parameter range of 0..1, the importer
did not properly detect whether the "U endpoint" flag should
be set on it. Fixed that, along with test coverage for the case.
---
 .../importer/obj_import_file_reader.cc        |  5 ++-
 .../importer/obj_import_nurbs.cc              |  9 ++++--
 .../importer/obj_import_objects.hh            |  1 +
 .../wavefront_obj/tests/obj_importer_tests.cc | 32 +++++++++++++++++++
 tests/data                                    |  2 +-
 5 files changed, 43 insertions(+), 6 deletions(-)

diff --git a/source/blender/io/wavefront_obj/importer/obj_import_file_reader.cc b/source/blender/io/wavefront_obj/importer/obj_import_file_reader.cc
index 650e9f37012..a59e2213793 100644
--- a/source/blender/io/wavefront_obj/importer/obj_import_file_reader.cc
+++ b/source/blender/io/wavefront_obj/importer/obj_import_file_reader.cc
@@ -358,9 +358,8 @@ static void geom_add_curve_vertex_indices(Geometry *geom,
                                           const char *end,
                                           const GlobalVertices &global_vertices)
 {
-  /* Curve lines always have "0.0" and "1.0", skip over them. */
-  float dummy[2];
-  p = parse_floats(p, end, 0, dummy, 2);
+  /* Parse curve parameter range. */
+  p = parse_floats(p, end, 0, geom->nurbs_element_.range, 2);
   /* Parse indices. */
   while (p < end) {
     int index;
diff --git a/source/blender/io/wavefront_obj/importer/obj_import_nurbs.cc b/source/blender/io/wavefront_obj/importer/obj_import_nurbs.cc
index 24ada0fbdaf..737bf3e09ff 100644
--- a/source/blender/io/wavefront_obj/importer/obj_import_nurbs.cc
+++ b/source/blender/io/wavefront_obj/importer/obj_import_nurbs.cc
@@ -78,16 +78,21 @@ void CurveFromGeometry::create_nurbs(Curve *curve)
   }
 
   BKE_nurb_knot_calc_u(nurb);
+
+  /* Figure out whether curve should have U endpoint flag set:
+   * the parameters should have at least (degree+1) values on each end,
+   * and their values should match curve range. */
   bool do_endpoints = false;
   int deg1 = nurbs_geometry.degree + 1;
   if (nurbs_geometry.parm.size() >= deg1 * 2) {
     do_endpoints = true;
+    const float2 range = nurbs_geometry.range;
     for (int i = 0; i < deg1; ++i) {
-      if (abs(nurbs_geometry.parm[i]) > 0.0001f) {
+      if (abs(nurbs_geometry.parm[i] - range.x) > 0.0001f) {
         do_endpoints = false;
         break;
       }
-      if (abs(nurbs_geometry.parm[nurbs_geometry.parm.size() - 1 - i] - 1.0f) > 0.0001f) {
+      if (abs(nurbs_geometry.parm[nurbs_geometry.parm.size() - 1 - i] - range.y) > 0.0001f) {
         do_endpoints = false;
         break;
       }
diff --git a/source/blender/io/wavefront_obj/importer/obj_import_objects.hh b/source/blender/io/wavefront_obj/importer/obj_import_objects.hh
index 31a21d3cd58..0a40398b177 100644
--- a/source/blender/io/wavefront_obj/importer/obj_import_objects.hh
+++ b/source/blender/io/wavefront_obj/importer/obj_import_objects.hh
@@ -69,6 +69,7 @@ struct NurbsElement {
    */
   std::string group_;
   int degree = 0;
+  float2 range{0.0f, 1.0f};
   /**
    * Indices into the global list of vertex coordinates. Must be non-negative.
    */
diff --git a/source/blender/io/wavefront_obj/tests/obj_importer_tests.cc b/source/blender/io/wavefront_obj/tests/obj_importer_tests.cc
index c37442edc03..c132c24ad84 100644
--- a/source/blender/io/wavefront_obj/tests/obj_importer_tests.cc
+++ b/source/blender/io/wavefront_obj/tests/obj_importer_tests.cc
@@ -316,6 +316,38 @@ TEST_F(OBJImportTest, import_nurbs_cyclic)
   import_and_check("nurbs_cyclic.obj", expect, std::size(expect), 0);
 }
 
+TEST_F(OBJImportTest, import_nurbs_endpoint)
+{
+  Expectation expect[] = {
+      {"OBCube", OB_MESH, 8, 12, 6, 24, float3(1, 1, -1), float3(-1, 1, 1)},
+      {"OBCurveEndpointRange01",
+       OB_CURVES_LEGACY,
+       15,
+       1,
+       4,
+       0,
+       float3(0.29f, 0, -0.11f),
+       float3(22.17f, 0, -5.31f)},
+      {"OBCurveEndpointRangeNon01",
+       OB_CURVES_LEGACY,
+       15,
+       1,
+       4,
+       0,
+       float3(0.29f, 0, -0.11f),
+       float3(22.17f, 0, -5.31f)},
+      {"OBCurveNoEndpointRange01",
+       OB_CURVES_LEGACY,
+       15,
+       0,
+       4,
+       0,
+       float3(0.29f, 0, -0.11f),
+       float3(22.17f, 0, -5.31f)},
+  };
+  import_and_check("nurbs_endpoint.obj", expect, std::size(expect), 0);
+}
+
 TEST_F(OBJImportTest, import_nurbs_manual)
 {
   Expectation expect[] = {
diff --git a/tests/data b/tests/data
index d8d9c4c5fbc..71e05fc367d 160000
--- a/tests/data
+++ b/tests/data
@@ -1 +1 @@
-Subproject commit d8d9c4c5fbca4e11c72fc7247b50655b8c9c7914
+Subproject commit 71e05fc367d26218dede9a97f4a0577a3b72a8c8