Overview
Shape grammar generation treats geometric elements as symbols and applies rules that split, replace, or decorate them.
ExtendedSource checked
Shape Grammar Generation
Generates geometry by repeatedly applying spatial rewrite rules to shapes.
Quick Facts
Compact metadata for implementation and discovery.
- Category
- Procedural Generation
- Difficulty
- Advanced
- Family
- Grammar-Based Generation
- Tier
- Extended
- Status
- Verified
- Review
- Source Checked
- Sources
- 2
- Formulas
- 1
- Relationships
- 3
- Code example
- Ready
- Visualization
- Ready
Core Concepts
shape rulespatial rewritederivation treegeometric constraint
Quick facts
Complexity
Runtime and memory behavior at a glance.
Best
O(output size)
Average
O(output size)
Worst
O(output size)
Space
O(output size)
When to Use
- Use when generating terrain needs shape rule.
- Use when the input matches the assumptions behind grammar-Based Generation.
When Not to Use
- Avoid when the design needs strict authored control over every generated detail.
- Avoid when a simpler algorithm gives the required result with less setup.
What It Does
- Generates geometry by repeatedly applying spatial rewrite rules to shapes
- Uses shape rule and spatial rewrite to guide the work.
- Produces generated map, texture, layout, or pattern.
Use Cases
- Generating terrain
- Creating textures
- Building levels or natural patterns
Inputs
- Seed
- Generation parameters
- Constraint rules
Outputs
- Generated map, texture, layout, or pattern
Key Formulas (1)
Shape rewrite
shape → transformed subshapes
shape -> transformed subshapesExpands one geometric element into a structured arrangement.
Pseudocode
- 1.Prepare the inputs and state needed for Shape Grammar Generation.
- 2.Apply the shape rule step while the stopping condition has not been met.
- 3.Update intermediate state and discard invalid candidates.
- 4.Return generated map, texture, layout, or pattern.
Canonical Example
- Input
- Shape Grammar Generation input with a small representative case
- Output
- Generated map, texture, layout, or pattern
- Explanation
- Shape Grammar Generation applies shape rule to produce generated map, texture, layout, or pattern.
Implementation Notes
- Keep the seed and parameters stored with generated output for reproducibility.
- Keep the shape rule step separate enough to test independently.
Common Pitfalls
- Small parameter changes can create large visual or structural differences.
- Forgetting to check edge cases can make Shape Grammar Generation look correct on only ideal inputs.
Interactive Mechanism Walkthrough
Spatial Primitive & Sweep-Line CanvasShow the generation state evolving from seed values to the final artifact.
Step 1 of 4: Prepare the inputs and state needed for Shape Grammar Generation.
procedural-generation-mechanismNotes
Shape Grammar Generation should be used with the assumptions and tradeoffs of grammar-Based Generation in mind.
Sources (2)
What each reference supports for this entry.
Procedural Content Generation in Games
BookProcedural-generation reference for rule-based spatial grammars and constructive content generation.
Open sourceIntroduction to Shape and Shape Grammars
PaperReference for shape grammar formalisms and recursive spatial rule generation.
Open sourceExplore Next
Good next jumps from the relationship graph, ranked for useful discovery.
Relationships
View full relationship pageConceptual neighborBinary Space Partitioning Dungeon Generation
Both can generate structured spatial layouts.
Variant ofGrammar-Based Generation
Shape grammars specialize grammar rules for spatial structures.
Tags
Procedural GenerationGrammar GenerationGeometryGeneration