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Assets/GameRes/Main/SceneArt/VRScene/Materials/GPUGrass/GrassTest.cs

@@ -0,0 +1,111 @@
+using System.Collections.Generic;
+using UnityEngine;
+using UnityEngine.Rendering;
+
+public class GrassTest : MonoBehaviour
+{
+    public Mesh mesh;
+    public Material material;
+    public Bounds bounds;
+    public float scaleMult;
+    public ShadowCastingMode shadowCastingMode;
+    public bool isReceiveShadow;
+
+    private ComputeBuffer instDataBuffer;
+    private ComputeBuffer argsBuffer;
+
+
+    // Mesh Properties struct to be read from the GPU.
+    // Size() is a convenience funciton which returns the stride of the struct.
+    public Transform root;
+    List<InstData> dataInfors = new List<InstData>();
+
+    private struct InstData
+    {
+        public Vector3 pos;
+        public Vector3 angle;
+        public Vector3 scale;
+
+        //
+        public static int GetNum()
+        {
+            return sizeof(float) * 3 + sizeof(float) * 3 + sizeof(float) * 3;
+        }
+    }
+
+
+
+
+
+
+    private void Start()
+    {
+        GetDataInfors();
+        InitializeBuffers();
+    }
+
+    private void Update()
+    {
+        Graphics.DrawMeshInstancedIndirect(mesh, 0, material, bounds, argsBuffer, 0, null, shadowCastingMode, isReceiveShadow, LayerMask.NameToLayer("Instance"));
+    }
+
+
+
+    void GetDataInfors()
+    {
+        foreach (Transform t in root.GetComponentInChildren<Transform>())
+        {
+            InstData instData = new InstData();
+            instData.pos = t.position;
+            instData.angle = t.eulerAngles;
+            instData.scale = t.localScale * scaleMult;
+            dataInfors.Add(instData);
+
+            //
+            t.gameObject.SetActive(false);
+        }
+    }
+
+
+
+    private void InitializeBuffers()
+    {
+        // Argument buffer used by DrawMeshInstancedIndirect.
+        uint[] args = new uint[5] { 0, 0, 0, 0, 0 };
+        // Arguments for drawing mesh.
+        // 0 == number of triangle indices, 1 == population, others are only relevant if drawing submeshes.
+        args[0] = (uint)mesh.GetIndexCount(0);
+        args[1] = (uint)dataInfors.Count;
+        args[2] = (uint)mesh.GetIndexStart(0);
+        args[3] = (uint)mesh.GetBaseVertex(0);
+        argsBuffer = new ComputeBuffer(1, args.Length * sizeof(uint), ComputeBufferType.IndirectArguments);
+        argsBuffer.SetData(args);
+
+        // Initialize buffer with the given population.
+        instDataBuffer = new ComputeBuffer(dataInfors.Count, InstData.GetNum());
+        instDataBuffer.SetData(dataInfors);
+        material = Instantiate(material);
+        material.SetBuffer("_InstDataBuffer", instDataBuffer);
+    }
+
+
+
+
+
+
+    private void OnDisable()
+    {
+        // Release gracefully.
+        if (instDataBuffer != null)
+        {
+            instDataBuffer.Release();
+        }
+        instDataBuffer = null;
+
+        if (argsBuffer != null)
+        {
+            argsBuffer.Release();
+        }
+        argsBuffer = null;
+    }
+}