ScrapReCover: An Interactive Optimization System for Freeform Patchwork Layouts

Masahiro Kono, Maria Larsson, I-Chao Shen, Takeo Igarashi
The University of Tokyo
SCF '25: ACM Symposium on Computational Fabrication (Full Conference Paper)
& WISS '25: Workshop on Interactive Systems and Software (Demo Presentation)
Teaser

ScrapReCover is an interactive tool for designing freeform patchwork layouts from fabric scraps. (a) Users begin by loading the scraps they wish to reuse. (b) Using ScrapReCover, they can iteratively refine the layout by combining manual adjustments of individual scraps with automatic placement suggestions guided by intuitive parameters. For automatic suggestions, the system arranges scraps within the target area, following an optimization strategy that minimizes material waste while ensuring complete coverage. (c) Finally, the resulting layout can be fabricated into a unique (collage-like) patchwork product.

Abstract

We present ScrapReCover, an interactive tool for designing freeform patchwork layouts from small leftover fabric scraps. The system enables users to iteratively refine the layout by combining manual adjustments of individual scraps with automatic placement suggestions guided by user-controlled parameters. These parameters can be intuitively adjusted to control the degree of modification from the current layout and to prioritize specific types of scraps. For automatic suggestions, the system generates layouts by arranging arbitrarily shaped scraps within the target area, using an optimization strategy that minimizes material waste while ensuring complete coverage. To achieve this functionality, ScrapReCover employs simulated annealing (SA), a robust metaheuristic and stochastic algorithm known for its effectiveness in packing-like problems, integrated with a rasterized representation of both scraps and pattern shapes. The usability of the system was validated through a user study in which 21 participants interactively generated layouts and fabricated patchworks from their own scraps. Additionally, the optimization method was evaluated by baseline comparisons which demonstrate that our approach outperforms other naive methods.

Demo Video

Proposed System: ScrapReCover

ScrapReCover allows users to iteratively design patchwork layouts through a combination of optimization-based automatic suggestion and manual adjustments.

UI Overview

The UI consists of five main components: Layout Workspace (top left, a-c), where scraps are placed onthe pattern; Available Scraps List (top right, d), which displays the unplaced scraps; Layout Control Panel (bottom left, e-g), a setof global layout controls; Placed Scraps List (bottom center, h), which enumerates the placed scraps; and Scrap Control Panel(bottom right, i–k), a set of controls for individual scraps.

"Hybrid Workflow" to Iteratively Refine The Layout

Auto

Automatic Suggestion via Optimization (SA)
Automatically places scraps to minimize waste while completely covering the target area.

Manual

Manual Adjustments
Drag, rotate, delete, and lock scraps manually.

"User-Controlled Sliders" to Guide The Optimization

Change Rate

Change Rate
Controls the degree of modification from the current layout. (Low: Minor, High: Drastic)

Reg Shape Pref

Regular Shape Preference
Globally prioritizes regular (High) vs. irregular (Low) shapes.

Selection Priority

Selection Priority
Adjusts the selection probability for individual scraps.

Fabricated Results

Some participants in our user study brought their own scraps, designed layouts using ScrapReCover (top) and subsequently fabricated a tote bag in real based on their designs (bottom).

Results

Citation

                
@inproceedings{kono2025scraprecover,
    title={ScrapReCover: An Interactive Optimization System for Freeform Patchwork Layouts},
    author={Kono, Masahiro and Larsson, Maria and Shen, I-Chao and Igarashi, Takeo},
    booktitle={Proceedings of the ACM Symposium on Computational Fabrication},
    pages={1--15},
    year={2025}
}