Procedural content generation (PCG) makes it possible to build massive environments, dynamic dungeons, and replayable game loops without manually placing every asset. But writing mesh-generation algorithms or noise-based terrain pipelines from scratch often lands you in performance hell—mostly due to CPU bottlenecks and heavy Garbage Collection (GC) spikes. Picking the right procedural asset means balancing engine workflows, spatial partitioning, C# Job System integration, and memory management.
Unity procedural tools generally run in one of two modes: editor-time or runtime. Editor-time tools let level designers pre-bake static geometry right into scenes, keeping runtime overhead virtually at zero. Runtime tools generate terrain, dungeons, or prop placements during loading screens or on the fly as players traverse the world.
Your core gameplay determines which algorithm you should reach for:
If you generate meshes at runtime, avoiding frame spikes comes down to strict memory discipline. Allocating temporary arrays during mesh construction quickly triggers GC pauses. Using Unity's NativeArray<T> alongside the Mesh.SetVertices API lets you stream generated geometry directly to GPU memory without throwing managed allocations onto the heap.
Here is a clean, low-allocation way to generate a procedural grid mesh using unmanaged memory buffers:
using Unity.Collections;
using UnityEngine;
[RequireComponent(typeof(MeshFilter), typeof(MeshRenderer))]
public class ProceduralGridGenerator : MonoBehaviour
{
[SerializeField] private int width = 32;
[SerializeField] private int height = 32;
[SerializeField] private float spacing = 1.0f;
public void GenerateGrid()
{
MeshFilter filter = GetComponent<MeshFilter>();
Mesh mesh = new Mesh { name = "Procedural Grid Mesh" };
int vertexCount = (width + 1) * (height + 1);
int indexCount = width * height * 6;
// Use Allocator.Temp for frame-bound memory allocations
NativeArray<Vector3> vertices = new NativeArray<Vector3>(vertexCount, Allocator.Temp);
NativeArray<Vector2> uvs = new NativeArray<Vector2>(vertexCount, Allocator.Temp);
NativeArray<int> indices = new NativeArray<int>(indexCount, Allocator.Temp);
for (int y = 0, i = 0; y <= height; y++)
{
for (int x = 0; x <= width; x++, i++)
{
vertices[i] = new Vector3(x * spacing, 0, y * spacing);
uvs[i] = new Vector2((float)x / width, (float)y / height);
}
}
for (int ti = 0, vi = 0, y = 0; y < height; y++, vi++)
{
for (int x = 0; x < width; x++, ti += 6, vi++)
{
indices[ti] = vi;
indices[ti + 1] = vi + width + 1;
indices[ti + 2] = vi + 1;
indices[ti + 3] = vi + 1;
indices[ti + 4] = vi + width + 1;
indices[ti + 5] = vi + width + 2;
}
}
mesh.SetVertices(vertices);
mesh.SetUVs(0, uvs);
mesh.SetIndices(indices, MeshTopology.Triangles, 0);
mesh.RecalculateNormals();
// Always dispose unmanaged NativeArrays
vertices.Dispose();
uvs.Dispose();
indices.Dispose();
filter.sharedMesh = mesh;
}
}
Taking procedural systems to production means keeping runtime costs predictably low. Offloading heavy calculations to parallel worker threads prevents the main CPU thread from stuttering during world streaming.
Mesh.CombineMeshes or use GPU instancing (Graphics.RenderMeshInstanced) to keep draw calls down when spawning thousands of props.GC Alloc column during generation runs. Watch out for accidental boxing inside nested loops.All Unity assets and tools featured in this guide are available for evaluation and testing through Ultimate Game Assets. Join our developer membership to access our full asset sandbox and speed up your production pipeline.