Once a 3D mesh and textures have been generated, the SimReady pipeline automatically computes physics properties and generates collision hulls. This stage transforms a visual mesh into a simulation-ready asset with accurate physical behavior.
Collision hulls define the physical boundaries of an object for physics simulation. Rather than using the full visual mesh (which can have millions of polygons), collision hulls are simplified convex shapes that the physics engine uses for collision detection.
Palatial uses the CoACD (Convex Approximate Convex Decomposition) algorithm to automatically decompose complex shapes into sets of convex hulls. The collision_quality parameter controls the trade-off between accuracy and performance.
Collision Quality Levels
| Quality | Description | Best Used For |
|---|---|---|
| low | Fast generation, rough bounding hulls. Fewer convex pieces. Suitable for objects where collision precision is not critical. | Simple objects, performance-critical scenes, rapid prototyping |
| medium | Balanced detail and performance. More convex pieces than low, capturing main shape features. | General-purpose objects, furniture, tools |
| high | Detailed decomposition with many convex pieces. Closely approximates the visual mesh boundaries. | Complex objects requiring accurate physics interactions |
| x_high | Extremely detailed decomposition. Maximum convex hull count for precise collision boundaries on complex geometry. | Highly detailed machinery, organic shapes, precision robotics |
| sdf | Signed Distance Field — most precise collision representation. Uses a volumetric distance field rather than convex hulls. Highest accuracy, higher compute cost. | Showcase assets, soft-body interactions, maximum fidelity requirements |
In addition to collision hulls, Palatial estimates the following physical properties for each asset:
When enable_parts_segmentation is enabled, Palatial uses the X-Part algorithm to automatically segment the mesh into semantic sub-parts. This is useful for multi-component rigid assemblies where different parts have separate physics properties (e.g., a table with a top surface and four legs).