Mesh.SetVertexBufferData

Parameters

Description

Sets the data of the vertex buffer of the Mesh.

Simple usage of Mesh scripting API involves using functions like vertices, normals to setup vertex data.

For advanced use cases that require maximum performance, you can use the advanced API, which has functions like SetSubMesh, SetIndexBufferParams, SetIndexBufferData, and SetVertexBufferParams. This advanced API gives access to the underlying mesh data structures that primarily work on raw index buffers, vertex buffers and mesh subset data.

You can use SetVertexBufferData to set vertex data directly, without using format conversions for each vertex attribute. The supplied data layout has to match the vertex data layout of the mesh (see SetVertexBufferParams, GetVertexAttributes). Partial updates of the data are also possible, via dataStart, meshBufferStart, count parameters.

using UnityEngine;
using UnityEngine.Rendering;
using Unity.Collections;

public class Example : MonoBehaviour
{
    // Vertex with FP32 position, FP16 2D normal and a 4-byte tangent.
    // In some cases StructLayout attribute needs
    // to be used, to get the data layout match exactly what it needs to be.
    [System.Runtime.InteropServices.StructLayout(System.Runtime.InteropServices.LayoutKind.Sequential)]
    struct ExampleVertex
    {
        public Vector3 pos;
        public ushort normalX, normalY;
        public Color32 tangent;
    }

    void Start()
    {
        var mesh = new Mesh();
        // specify vertex count and layout
        var layout = new[]
        {
            new VertexAttributeDescriptor(VertexAttribute.Position, VertexAttributeFormat.Float32, 3),
            new VertexAttributeDescriptor(VertexAttribute.Normal, VertexAttributeFormat.Float16, 2),
            new VertexAttributeDescriptor(VertexAttribute.Tangent, VertexAttributeFormat.UNorm8, 4),
        };
        var vertexCount = 10;
        mesh.SetVertexBufferParams(vertexCount, layout);

        // set vertex data
        var verts = new NativeArray<ExampleVertex>(vertexCount, Allocator.Temp);

        // ... fill in vertex array data here...

        mesh.SetVertexBufferData(verts, 0, 0, vertexCount);
    }
}

Additional resources: SetVertexBufferParams, SetIndexBufferParams, SetIndexBufferData, SetSubMesh, MeshUpdateFlags, AcquireReadOnlyMeshData.