Autoregressive models have proven effective for triangular mesh generation by transforming it into predicting the next face, converting the non-differentiable connectivity prediction into a sequence of token predictions. However, generating quad-only meshes remains challenging because quad faces impose stricter topological constraints than triangles. The model must not only serialize quad faces into a valid token sequence, but also support unambiguous connectivity reconstruction during de-serialization. To address this, we propose Q-MAGIC, a novel autoregressive model for quad mesh generation. We first introduce a tailored serialization scheme for quad meshes, which requires at least two new vertices for the next face and is less flexible than triangles due to strict wiring constraints. To meet these requirements and reduce serialization length, we propose a singularity-aware serialization that prioritizes wiring from singular points, leading to more coherent traversals. Additionally, we propose a circular relative offset tokenization that encodes geometry mainly via local relative offsets. Built upon this representation, an autoregressive Transformer learns the underlying distribution of quad meshes via next-token prediction, enabling effective quad mesh generation. Extensive experiments demonstrate that Q-MAGIC produces more compact sequences while consistently improving geometric fidelity and mesh quality compared to state-of-the-art methods.
Figures & tables
Figure 1: Overview of the Q-MAGIC. We adopt a singularity-aware serialization strategy that prioritizes critical singularities in the sequence. In our token representation, geometric information is mainly encoded by circular relative offsets, and block tokens are inserted only when necessary to re-anchor the spatial location, enabling a compact representation. During inference, Q-MAGIC conditions on point clouds and autoregressively generates quad meshes.
Figure 2: Overview of circular relative offset tokenization. Left: each vertex is represented by a block–offset pair (B,O) . Right: For intra-block moves, we emit only Δon (wrapping to the bounded interval when needed); when crossing a block boundary, we emit the new block index B and then continue with relative offsets. Bottom: the resulting token sequence with BOS/EOS, consisting of block tokens and circular relative offset tokens.
Figure 3: De-serialization in Q-MAGIC. (a) Consecutive records recover the shared vertex from the last vertex of the previous face. (b,c) Directly connecting adjacent tokens for non-consecutive records may generate invalid red dashed quads. We resolve this issue via a novel de-serialization scheme. Quads are reconstructed from the recorded non-center vertices under the face of the current local patch, ensuring consistent local topology.
Method
QGPT
MAV2
EG
DM
BPT
Ours
Avg. Len.
43106
29000
28497
20675
14104
12655
Comp. Ratio
1
0.67
0.66
0.48
0.33
0.29
Table 1: Average sequence length comparison. QGPT, MAV2, EG, and DM denote QuadGPT, MeshAnythingV2, EdgeRunner and DeepMesh. Our serialization yields the lowest token length on the same mesh set.
Figure 4: Visualization results and close-up views of generated quad meshes. Our method can better preserve continuous boundary loops and structured quad layouts in detail-sensitive regions, producing more regular and stable quad meshes.
Model
Point2Quad
TMGPT
QuadGPT
BPT
Ours
SJ ↑−11
0.9726
0.8879
0.9727
0.9762
0.9829
WT ↑01
0.9995
0.8921
0.9836
0.9873
0.9996
MF ↑01
1
0.9989
0.9998
0.9998
0.9999
CD ↓0∞
0.0717
0.1704
0.0854
0.0719
0.0684
HD ↓0∞
0.1069
0.3255
0.1374
0.1299
0.1058
SR ↓01
0.3050
0.8715
0.2164
0.4000
0.2310
Table 2: Quantitative comparison. ↑ba and ↓ba denote that larger and smaller values are better, respectively. Here, a and b represent the upper and lower bounds.SJ, WT, MF, CD, HD, SR and US denote Scaled Jacobian, Watertightness, Manifoldness, Chamfer distance, Hausdorff distance, singularity rate and user study.
Metrics
Random
Singularity-aware
Scaled Jacobian ↑−11
0.8862
0.9829
Watertightness ↑01
0.9429
0.9996
Manifoldness ↑01
0.9986
0.9999
Chamfer distance ↓0∞
0.2202
0.0684
Hausdorff distance ↓0∞
0.3906
0.1058
Table 3: Ablation study on patch serialization policies under circular relative offset tokenization (Random vs. singularity-aware).
Metrics
Block-offset
Circ. relative offset
Scaled Jacobian ↑−11
0.7442
0.9829
Watertightness ↑01
0.6635
0.9996
Manifoldness ↑01
0.9993
0.9999
Chamfer distance ↓0∞
0.3161
0.0684
Hausdorff distance ↓0∞
0.5487
0.1058
Table 4: Ablation study on serialization scheme under the default singularity-aware traversal (Circular relative offset vs. Block-offset).
Figure 5: Qualitative ablation on serialization schemes.
Figure 6: Qualitative ablation on patch traversal order.
The University of Hong Kong, Deemos Technology Co., Ltd. , China · ShanghaiTech University, Deemos Technology Co., Ltd., China · Shandong University, China +3