Scale error in mesh optimizer so it uses absolute scale.

Switch to simplify sloppy for another try.

Update to meshoptimizer e3f53f66e7a35b9b8764bee478589d79e34fa698.

1 files changed, 42 insertions, 4 deletions

diff --git a/editor/import/scene_importer_mesh.cpp b/editor/import/scene_importer_mesh.cpp
index cd7d58c6f6..620437af0e 100644
--- a/editor/import/scene_importer_mesh.cpp
+++ b/editor/import/scene_importer_mesh.cpp
@@ -140,6 +140,12 @@ void EditorSceneImporterMesh::generate_lods() {
 	if (!SurfaceTool::simplify_func) {
 		return;
 	}
+	if (!SurfaceTool::simplify_scale_func) {
+		return;
+	}
+	if (!SurfaceTool::simplify_sloppy_func) {
+		return;
+	}
 
 	for (int i = 0; i < surfaces.size(); i++) {
 		if (surfaces[i].primitive != Mesh::PRIMITIVE_TRIANGLES) {
@@ -157,20 +163,52 @@ void EditorSceneImporterMesh::generate_lods() {
 
 		int min_indices = 10;
 		int index_target = indices.size() / 2;
-		print_line("total: " + itos(indices.size()));
+		print_line("Total indices: " + itos(indices.size()));
+		float mesh_scale = SurfaceTool::simplify_scale_func((const float *)vertices_ptr, vertex_count, sizeof(Vector3));
+		const float target_error = 1e-3f;
+		float abs_target_error = target_error / mesh_scale;
 		while (index_target > min_indices) {
 			float error;
 			Vector<int> new_indices;
 			new_indices.resize(indices.size());
-			size_t new_len = SurfaceTool::simplify_func((unsigned int *)new_indices.ptrw(), (const unsigned int *)indices.ptr(), indices.size(), (const float *)vertices_ptr, vertex_count, sizeof(Vector3), index_target, 1e20, &error);
-			print_line("shoot for " + itos(index_target) + ", got " + itos(new_len) + " distance " + rtos(error));
+			size_t new_len = SurfaceTool::simplify_func((unsigned int *)new_indices.ptrw(), (const unsigned int *)indices.ptr(), indices.size(), (const float *)vertices_ptr, vertex_count, sizeof(Vector3), index_target, abs_target_error, &error);
 			if ((int)new_len > (index_target * 120 / 100)) {
+				// Attribute discontinuities break normals.
+				bool is_sloppy = false;
+				if (is_sloppy) {
+					abs_target_error = target_error / mesh_scale;
+					index_target = new_len;
+					while (index_target > min_indices) {
+						Vector<int> sloppy_new_indices;
+						sloppy_new_indices.resize(indices.size());
+						new_len = SurfaceTool::simplify_sloppy_func((unsigned int *)sloppy_new_indices.ptrw(), (const unsigned int *)indices.ptr(), indices.size(), (const float *)vertices_ptr, vertex_count, sizeof(Vector3), index_target, abs_target_error, &error);
+						if ((int)new_len > (index_target * 120 / 100)) {
+							break; // 20 percent tolerance
+						}
+						sloppy_new_indices.resize(new_len);
+						Surface::LOD lod;
+						lod.distance = error * mesh_scale;
+						abs_target_error = lod.distance;
+						if (Math::is_equal_approx(abs_target_error, 0.0f)) {
+							return;
+						}
+						lod.indices = sloppy_new_indices;
+						print_line("Lod " + itos(surfaces.write[i].lods.size()) + " shoot for " + itos(index_target / 3) + " triangles, got " + itos(new_len / 3) + " triangles. Distance " + rtos(lod.distance) + ". Use simplify sloppy.");
+						surfaces.write[i].lods.push_back(lod);
+						index_target /= 2;
+					}
+				}
 				break; // 20 percent tolerance
 			}
 			new_indices.resize(new_len);
 			Surface::LOD lod;
-			lod.distance = error;
+			lod.distance = error * mesh_scale;
+			abs_target_error = lod.distance;
+			if (Math::is_equal_approx(abs_target_error, 0.0f)) {
+				return;
+			}
 			lod.indices = new_indices;
+			print_line("Lod " + itos(surfaces.write[i].lods.size()) + " shoot for " + itos(index_target / 3) + " triangles, got " + itos(new_len / 3) + " triangles. Distance " + rtos(lod.distance));
 			surfaces.write[i].lods.push_back(lod);
 			index_target /= 2;
 		}