On Ground iCrowd System - User Documentation

Overview

The On Ground System creates natural-looking static crowds scattered across terrain, perfect for park scenes, outdoor events, queues, and social gatherings with both individual agents and social groups.

Distribution Tab

Basic Setup

  • View Mode: Render - Standard visualization
  • Terrain: On Ground Terrain - Input terrain collection for agent placement

Distribution Types

1. Singles

Individual scattered agents - Density: 0.200 - Overall density of individual agents - Min Distance: 1m - Minimum spacing between single agents - Seed: 1 - Randomization pattern - Max Agents: 100,000.000 - Maximum number limit

2. Clusters

Social groups and clusters - Density: 0.060 - Density of cluster centers - Min Distance: 6.39m - Spacing between different clusters - Seed: 0 - Randomization pattern - Max Clusters: 100,000.000 - Maximum cluster count

Distribution Controls

Weight Painting

  • Brush Tool: Paint density variations directly on terrain
  • Vertex Group Mask: Use predefined vertex groups for density control
  • Application: Create natural density variations like pathways vs open areas

Sphere Mask

  • Sphere Object: Use sphere objects to define inclusion/exclusion zones
  • Edit: Modify sphere position and radius for precise area control

Personal Space System

  • Relax Iterations: 12 - Processing passes for collision resolution
  • Min Distance: 0.500m - Minimum personal space between agents
  • Max Distance: 1.000m - Maximum personal space buffer
  • Seed: 0 - Randomization for personal space variation

Cluster Variations

Radius Settings

  • Min Radius: 0.000m - Smallest cluster size
  • Max Radius: 1.000m - Largest cluster size
  • Seed: 6 - Randomization pattern
  • Relax Iterations: 1.329 - Cluster formation quality
  • Noise: 1.000 - Natural variation in cluster shapes

Population Settings

  • Min Count: 5 - Minimum agents per cluster
  • Max Count: 12 - Maximum agents per cluster
  • Seed: 0 - Randomization for cluster sizes

Placement Settings

  • Offset: Random positioning variation within clusters
  • Creates: More organic, natural-looking group formations

Settings Tab

Orientation Control

Rotation Modes

  1. Default
  2. Consistent facing direction across all agents

  3. Uniform crowd appearance

  4. Randomize

  5. Random rotation per agent
  6. Natural-looking varied crowd

  7. Control: Adjust randomization intensity

  8. At Object

  9. All agents face toward target object
  10. Optional: Add randomization for natural variation
  11. Use: Crowds facing a stage, speaker, or point of interest

Scale Variations

  • Size Randomization: Control agent size variations
  • Natural Variation: Avoid uniform, artificial appearance
  • Scale Range: Adjust minimum and maximum size parameters

Agent Configuration

Input Requirements

  • Animated Agents: Collections with idle animations
  • Multiple Collections: Support for varied agent types
  • Probability Control: Balance between different agent collections

Customization

  • Custom Collections: Import additional agent types
  • Clothing Variations: Modify agent appearances within collections
  • Collection Blending: Mix different agent types naturally

Typical Workflow

  1. Terrain Setup
  2. Prepare ground terrain collection

  3. Define areas using weight painting or sphere masks

  4. Singles Distribution

  5. Set density for individual agents
  6. Adjust personal space for natural spacing

  7. Use weight painting for area-specific density

  8. Clusters Setup

  9. Configure cluster density and spacing
  10. Set cluster size variations (radius and population)

  11. Adjust cluster formation parameters

  12. Orientation & Scale

  13. Choose rotation mode based on scene needs
  14. Set scale variations for natural appearance

  15. Fine-tune facing directions

  16. Agent Assignment

  17. Select agent collections
  18. Balance probabilities between collections
  19. Add custom agents if needed

Best Practices

For Realistic Results

  • Use Singles for background crowds and individuals
  • Use Clusters for social groups and gatherings
  • Combine both types for most natural scenes
  • Use weight painting to follow terrain features and paths
  • Apply personal space to prevent agent overlapping

Performance Optimization

  • Start with lower densities and increase gradually
  • Use appropriate relax iterations (higher = better quality but slower)
  • Balance cluster counts with scene complexity
  • Use sphere masks to limit calculations to visible areas

Natural Appearance Tips

  • Use random rotation with moderate variation
  • Apply scale variations for diverse crowd
  • Mix cluster sizes for organic social groups
  • Use noise and offset for irregular cluster shapes

Use Cases

  • Park scenes with people sitting and standing
  • Outdoor events like concerts or festivals
  • Queue simulations for attractions or services
  • Public squares and gathering places
  • Beach scenes with scattered groups
  • Marketplaces and social spaces

The On Ground System creates the most organic and natural-looking static crowds, ideal for environments where people gather informally and social dynamics are important.