Repository Analysis

libigl/libigl

Simple MPL-2.0-licensed C++ geometry processing library.

10.7 Low AI signal View on GitHub

Analysis Overview

This report presents the forensic synthetic code analysis of libigl/libigl, a C++ project with 5,078 GitHub stars. SynthScan v2.0 examined 170,426 lines of code across 1587 source files, recording 1795 pattern matches distributed across 7 syntactic categories. The overall adjusted score of 10.7 places this repository in the Low AI signal band.

The scanner applied 160+ deterministic lexical heuristics, multi-line block detectors, abstract syntax tree depth profilers, and a cross-file Jaccard similarity matrix to construct a statistically normalised synthetic code estimate. All matches are individually weighted by severity coefficient and contextual multiplier before summation, and the resulting headline score is temporally discounted to account for the repository's development history relative to the commercial emergence of large language model coding tooling (November 2022 onward).

10.7
Adjusted Score
10.7
Raw Score
100%
Time Factor
2026-08-26
Last Push
5.1K
Stars
C++
Language
170.4K
Lines of Code
1.6K
Files
1.8K
Pattern Hits
2026-08-29
Scan Date
0.00
HC Hit Rate

What These Metrics Mean

Adjusted Score
Primary synthetic code indicator. Raw score normalised per 1,000 lines of code and multiplied by the temporal discount factor. This is the definitive comparative metric — use it to rank repositories by AI authorship density.
Raw Score
The unmodified sum of all severity-weighted, context-multiplied pattern match scores before temporal discounting. Reflects the absolute signal strength independent of when the repository was last active.
Time Factor
The temporal discount multiplier (0–100%) applied to the raw score. Repositories last updated before ChatGPT's launch (Nov 2022) receive a 5% factor. Full signal is only assigned to repositories active in the post-adoption era (Jan 2024+).
Pattern Hits
Total count of individual pattern matches across all files and categories. A high hit count with a low score may indicate a very large codebase with isolated AI snippets; a low count with a high score indicates dense, concentrated AI signatures.
HC Hit Rate
High+Critical pattern hits per file, averaged across the repository. This orthogonal signal catches repositories where a few files are densely packed with high-severity AI tells — a strong indicator even when the normalised score appears moderate due to codebase size.
Lines of Code / Files
Total lines and files analysed. The scanner examines 94 file extensions. These denominators are used to normalise the score, enabling fair comparison between repositories of vastly different sizes.

Score History

Longitudinal tracking requires multiple scan runs. Once this repository is re-scanned after new commits land, this chart will visualise how the synthetic code signal evolves over time — enabling you to detect whether AI authorship is growing, stabilising, or being actively corrected by human engineers.

No multi-scan history yet — run the scanner again to build trend data.

Severity Breakdown

Classifies detected patterns by their diagnostic confidence and structural impact. CRITICAL patterns (coefficient 10) represent definitive synthetic signatures — hallucinated imports, explicit LLM attribution metadata — virtually never produced by human authors. HIGH (5) indicates strong structural tells such as cross-file repetition or cross-linguistic idioms. MEDIUM (2) covers recognisable conversational padding and AI-specific vocabulary. LOW (1) captures subtle indicators like tautological comments and generic boilerplate that require density to carry independent signal.

CRITICAL 0HIGH 1MEDIUM 15LOW 1779

Directory Score Breakdown

This horizontal bar chart decomposes the repository's raw synthetic code score by top-level directory, allowing you to pinpoint precisely which modules or components carry the highest AI authorship density. Directories with disproportionately high scores relative to their size warrant targeted manual review: concentrated AI signatures often trace back to mass-generated configuration layers, auto-ported test suites, LLM-scaffolded boilerplate classes, or entire subsystems authored under heavy copilot assistance. Use this view to prioritise your human code-review effort.

Pattern Findings

The scanner identified 1795 distinct pattern matches across 7 syntactic categories. Each entry below represents a discrete location in the source code where the engine recorded a statistically significant AI authorship indicator. Expand any category row to inspect the individual file paths, line numbers, code snippets, and the lexical context (CODE, COMMENT, or STRING) in which each match was detected.

Reading the findings table: The Severity column indicates the diagnostic confidence level (CRITICAL / HIGH / MEDIUM / LOW). The Context column identifies whether the match occurred inside executable code, an inline comment, or a string literal — comment-context matches receive a ×1.5 weight because LLMs systematically over-annotate. The ⚡ bolt icon marks clustered matches: three or more patterns within a 10-line window, each receiving an additional ×1.5 density multiplier as dense clusters constitute far stronger evidence of synthetic authorship than isolated hits.

Over-Commented Block1768 hits · 1758 pts
SeverityFileLineSnippetContext
LOW…rial/406_FastAutomaticSkinningTransformations/main.cpp1#include "precomputation.h"COMMENT
LOWtutorial/704_SignedDistance/main.cpp1#include <igl/cat.h>COMMENT
LOWtutorial/707_SweptVolume/main.cpp1#include <igl/read_triangle_mesh.h>COMMENT
LOWtutorial/807_FastWindingNumber/main.cpp1#include <igl/fast_winding_number.h>COMMENT
LOWtutorial/1004_SplineDistance/main.cpp1#include <igl/opengl/glfw/Viewer.h>COMMENT
LOWtutorial/1001_LipschitzOctree/main.cpp1#include <igl/read_triangle_mesh.h>COMMENT
LOWtutorial/804_MarchingTets/main.cpp1#include <igl/opengl/glfw/Viewer.h>COMMENT
LOWtutorial/709_SLIM/param_2d_demo_iter.cpp1#include "param_2d_demo_iter.h"COMMENT
LOWtutorial/709_SLIM/main.cpp1#include "check_mesh_for_issues.h"COMMENT
LOWtutorial/901_VectorFieldSmoothing/main.cpp1#include <igl/read_triangle_mesh.h>COMMENT
LOWtutorial/405_AsRigidAsPossible/main.cpp1#include <igl/colon.h>COMMENT
LOWtutorial/403_BoundedBiharmonicWeights/main.cpp1#include <igl/boundary_conditions.h>COMMENT
LOWtutorial/403_BoundedBiharmonicWeights/main.cpp121 // compute BBW weights matrixCOMMENT
LOWtutorial/203_CurvatureDirections/main.cpp1#include <igl/avg_edge_length.h>COMMENT
LOWtutorial/902_VectorParallelTransport/main.cpp1#include <igl/read_triangle_mesh.h>COMMENT
LOWtutorial/303_LaplaceEquation/main.cpp1#include <igl/boundary_facets.h>COMMENT
LOWtutorial/810_BlueNoise/main.cpp1// This file is part of libigl, a simple c++ geometry processing library.COMMENT
LOWtutorial/703_Decimation/main.cpp1#include <igl/circulation.h>COMMENT
LOWtutorial/910_OrientedBoundingBox/main.cpp1#include <igl/read_triangle_mesh.h>COMMENT
LOWtutorial/504_Planarization/main.cpp1#include <igl/avg_edge_length.h>COMMENT
LOWtutorial/205_Laplacian/main.cpp1#include <igl/barycenter.h>COMMENT
LOWtutorial/407_BiharmonicCoordinates/main.cpp1#include <igl/opengl/gl.h>COMMENT
LOWtutorial/407_BiharmonicCoordinates/main.cpp61 assert(sqrD.minCoeff() < 1e-7 && "low.V should exist in high.V");COMMENT
LOWtutorial/710_SCAF/main.cpp1#include <igl/triangle/scaf.h>COMMENT
LOWtutorial/907_DynamicAABB/main.cpp1#include <igl/AABB.h>COMMENT
LOWtutorial/604_Triangle/main.cpp21COMMENT
LOWtutorial/404_DualQuaternionSkinning/main.cpp1#include <igl/directed_edge_orientations.h>COMMENT
LOWtutorial/908_IntersectionBlockingDecimation/main.cpp1#include <igl/opengl/glfw/Viewer.h>COMMENT
LOWtutorial/602_Matlab/main.cpp1COMMENT
LOWtutorial/802_DataSmoothing/main.cpp1#include <igl/read_triangle_mesh.h>COMMENT
LOWtutorial/805_MeshImplicitFunction/contours.cpp1#include "contours.h"COMMENT
LOWtutorial/809_ExplodedView/main.cpp1// This file is part of libigl, a simple c++ geometry processing library.COMMENT
LOWtutorial/304_LinearEqualityConstraints/main.cpp1#include <igl/boundary_facets.h>COMMENT
LOWtutorial/808_IterativeClosestPoint/main.cpp1// This file is part of libigl, a simple c++ geometry processing library.COMMENT
LOWtutorial/1002_EytzingerAABB/main.cpp1#include <igl/read_triangle_mesh.h>COMMENT
LOWtutorial/803_ShapeUp/main.cpp1#include <igl/avg_edge_length.h>COMMENT
LOWtutorial/601_Serialization/main.cpp21 this->Add(V , "V");COMMENT
LOWtutorial/601_Serialization/main.cpp41// {COMMENT
LOW…l/Singular_Value_Decomposition_Kernel_Declarations.hpp1//#####################################################################COMMENT
LOW…l/Singular_Value_Decomposition_Kernel_Declarations.hpp21#ifdef PRINT_DEBUGGING_OUTPUTCOMMENT
LOW…l/Singular_Value_Decomposition_Kernel_Declarations.hpp41#ifdef USE_AVX_IMPLEMENTATIONCOMMENT
LOWinclude/igl/NormalType.h1// This file is part of libigl, a simple c++ geometry processing library.COMMENT
LOWinclude/igl/lscm.h1// This file is part of libigl, a simple c++ geometry processing library.COMMENT
LOWinclude/igl/lscm.h21 /// Generation" [Lévy et al. 2002]), though this implementation follows theCOMMENT
LOWinclude/igl/moments.h1// This file is part of libigl, a simple c++ geometry processing library.COMMENT
LOWinclude/igl/loop.cpp1// This file is part of libigl, a simple c++ geometry processing library.COMMENT
LOWinclude/igl/is_dir.h1// This file is part of libigl, a simple c++ geometry processing library.COMMENT
LOWinclude/igl/shapeup.cpp1// This file is part of libigl, a simple c++ geometry processing library.COMMENT
LOWinclude/igl/comb_frame_field.h1// This file is part of libigl, a simple c++ geometry processing library.COMMENT
LOWinclude/igl/MshLoader.h1// based on MSH reader from PyMesh COMMENT
LOWinclude/igl/trackball.h1// This file is part of libigl, a simple c++ geometry processing library.COMMENT
LOWinclude/igl/unzip_corners.h1// This file is part of libigl, a simple c++ geometry processing library.COMMENT
LOWinclude/igl/unzip_corners.h21 ///COMMENT
LOWinclude/igl/cubic_split.h1#ifndef IGL_CUBIC_SPLIT_HCOMMENT
LOWinclude/igl/FileMemoryStream.h1// This file is part of libigl, a simple c++ geometry processing library.COMMENT
LOWinclude/igl/SolverStatus.h1// This file is part of libigl, a simple c++ geometry processing library.COMMENT
LOWinclude/igl/tan_half_angle.h1// This file is part of libigl, a simple c++ geometry processing library.COMMENT
LOWinclude/igl/circulation.h1// This file is part of libigl, a simple c++ geometry processing library.COMMENT
LOWinclude/igl/circulation.h21 /// E(e,1))COMMENT
LOWinclude/igl/circulation.h41 /// @param[in] e index into E of edge to circulateCOMMENT
1708 more matches not shown…
AI Slop Vocabulary8 hits · 24 pts
SeverityFileLineSnippetContext
MEDIUMinclude/igl/WindingNumberAABB.h259 //// Perfect matching is **not** robustCOMMENT
MEDIUMinclude/igl/arap.h108 /// a map to the position data, allowing seamless interoperability with user-definedCOMMENT
MEDIUMinclude/igl/tri_tri_intersect.cpp618 // Alec: it's hard to believe this will ever be perfectly robust, but checkingCOMMENT
MEDIUMinclude/igl/harmonic.cpp130 // This is **not** robust for k>2. See KKT system in [Jacobson et al. 2010]COMMENT
MEDIUMinclude/igl/flipped_triangles.cpp24 // https://www.cs.cmu.edu/~quake/robust.htmlCOMMENT
MEDIUMinclude/igl/sort_angles.h15 /// Sort angles in ascending order in a numerically robust way.COMMENT
MEDIUMinclude/igl/seam_edges.cpp43 // Based on: https://www.cs.cmu.edu/~quake/robust.htmlCOMMENT
MEDIUMinclude/igl/copyleft/cgal/outer_facet.h29 /// function is more robust because it does not rely on facet normals.COMMENT
Modern AI Meta-Vocabulary6 hits · 18 pts
SeverityFileLineSnippetContext
MEDIUMinclude/igl/triangle/scaf.h23 /// For a complete implementation and customized UI, please refer to https://github.com/jiangzhongshi/scaffold-mapCOMMENT
MEDIUMinclude/igl/triangle/scaf.h32 /// scaffold + isometricCOMMENT
MEDIUMinclude/igl/triangle/scaf.h47 /// scaffold domain tets: scaffold tetsCOMMENT
MEDIUMinclude/igl/triangle/scaf.h53 /// scaffold area or volumeCOMMENT
MEDIUMinclude/igl/triangle/scaf.h122 /// @param[in] whole: Include scaffold if trueCOMMENT
MEDIUMinclude/igl/triangle/scaf.cpp525 // x_e as the fixed frame, x_u for unknowns (mesh + unknown scaffold)COMMENT
Fake / Example Data10 hits · 14 pts
SeverityFileLineSnippetContext
LOWtests/include/igl/writePLY.cpp24 Vheader1.push_back("dummy_data");CODE
LOWtests/include/igl/writePLY.cpp25 Eigen::VectorXd dummy_data(V1.rows());CODE
LOWtests/include/igl/writePLY.cpp27 dummy_data(i)=(double)i;CODE
LOWtests/include/igl/writePLY.cpp29 VD2<<VD1,dummy_data;CODE
LOWtests/include/igl/writePLY.cpp100 REQUIRE (Vheader[2] == "dummy_data" );CODE
LOWtests/include/igl/writePLY.cpp144 Vheader1.push_back("dummy_data");CODE
LOWtests/include/igl/writePLY.cpp145 Eigen::VectorXf dummy_data(V1.rows());CODE
LOWtests/include/igl/writePLY.cpp147 dummy_data(i)=(double)i;CODE
LOWtests/include/igl/writePLY.cpp149 VD2<<VD1,dummy_data;CODE
LOWtests/include/igl/writePLY.cpp187 REQUIRE (Vheader[2] == "dummy_data" );CODE
AI Response Leakage1 hit · 8 pts
SeverityFileLineSnippetContext
HIGHinclude/igl/raytri.c11// Alec: I've added an include guard, made all functions inline and addedCOMMENT
Slop Phrases1 hit · 3 pts
SeverityFileLineSnippetContext
MEDIUMtutorial/602_Matlab/main.cpp54 // Plot the size of EV (only for demonstration purposes)COMMENT
Example Usage Blocks1 hit · 2 pts
SeverityFileLineSnippetContext
LOWinclude/igl/signed_distance.h262 /// #### Usage:COMMENT