meshID | The instance ID of the Mesh to bake collision data from. |
convex | A flag to indicate whether to bake convex geometry or not. |
Prepares the Mesh for use with a MeshCollider.
This function runs Mesh baking and saves the result in the Mesh itself. When a MeshCollider referencing this Mesh is instantiated, it reuses the baked data instead of re-baking the Mesh. This is useful when you want to move the expensive baking process from the Scene load time or instantiation time to a different moment in time. BakeMesh is thread-safe, and does computations on the thread it was called from. You can use BakeMesh with the C# job system. Here is an example:
using UnityEngine;
public class MinimalTest : MonoBehaviour { public Mesh mesh;
private MeshCollider collider;
private void OnEnable() { // Bake this Mesh to use later. Physics.BakeMesh(mesh.GetInstanceID(), false); }
public void FixedUpdate() { // If the collider wasn't yet created - create it now. if (collider == null) { // No mesh baking will happen here because the mesh was pre-baked, making instantiation faster. collider = new GameObject().AddComponent<MeshCollider>(); collider.sharedMesh = mesh; } } }
BakeMesh is thread-safe, and does computations on the thread it was called from. You can use BakeMesh with the C# job system. This example shows how to bake meshes across multiple threads so that MeshCollider instantiation takes less time on the main thread.
using Unity.Collections; using Unity.Jobs; using UnityEngine;
public struct BakeJob : IJobParallelFor { private NativeArray<int> meshIds;
public BakeJob(NativeArray<int> meshIds) { this.meshIds = meshIds; }
public void Execute(int index) { Physics.BakeMesh(meshIds[index], false); } }
public class JobifiedBaking : MonoBehaviour { public Mesh[] meshes; public int meshesPerJob = 10;
// Bake all the Meshes off of the main thread, and then instantiate on the main thread. private void OnEnable() { // You cannot access GameObjects and Components from other threads directly. // As such, you need to create a native array of instance IDs that BakeMesh will accept. NativeArray<int> meshIds = new NativeArray<int>(meshes.Length, Allocator.TempJob);
for (int i = 0; i < meshes.Length; ++i) { meshIds[i] = meshes[i].GetInstanceID(); }
// This spreads the expensive operation over all cores. var job = new BakeJob(meshIds); job.Schedule(meshIds.Length, meshesPerJob).Complete();
meshIds.Dispose();
// Now instantiate colliders on the main thread. for (int i = 0; i < meshes.Length; ++i) { new GameObject().AddComponent<MeshCollider>().sharedMesh = meshes[i]; } } }