Grid-based Genetic Operators
for Graphical Layout Generation
Morteza Shiripour, Niraj Ramesh Dayama, Antti Oulasvirta
Aalto University, Finland
EICS 2021
Layout design
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Many-objective optimization problem
𝑀 is the number of objectives
𝑥 is the feasible set of decision variables
Ω is the set of all boundaries and constraints
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How to solve this problem?
● Classical approaches:
○ Weighted-sum and 𝜖-constraint
i. Multiple runs are required
ii. Obtaining the full Pareto front is difficult
iii. Sensitive to the Pareto front’s shape
iv. Linear approximation techniques for some objectives
● Evolutionary approaches:
○ Non-dominated sorting genetic algorithm (NSGA) III
i. Easy to implement
ii. A broad applicability
iii. Robust to dynamic changes
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The proposed
NSGA-III flowchart
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Chromosome representation
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Initial generation
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Original uniform-crossover operator
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Grid-based crossover operator
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Grid-based
crossover steps
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Performance comparison
Inverted generational distance (IGD)
is the minimum distance from
Pareto reference 𝑖 to Pareto solution 𝑞
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Performance comparison
Hypervolume (HV)
𝑆 is an index for the Pareto approximation solutions
𝑅 is a reference point
is the volume of solution 𝑖
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Pareto presentation
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Perceived quality by users
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Conclusion
● All the solutions generated satisfy the no-overlap requirement
● Representing well-formed layouts
● The efficiency of the generated layouts was verified by users
Future work
● Exploring new objectives and their effects on performance
● Emerging work that combines machine learning approaches
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Thank you!
Funding:
Technology Industries of Finland
Academy of Finland
Email:
shiripour.morteza@aalto.fi

Grid-based Genetic Operators for Graphical Layout Generation