//http://www.klayge.org/?p=3006
public static Vector3[] GetRandomDirs_BlinnPhong_Importance(Vector3 faceNormal, Vector3 reflectDir, float smoothness, int num)
{
Vector3[] rlt = new Vector3[num];
float reflectAngle = Mathf.Acos(Vector3.Dot(reflectDir, faceNormal)); //镜面反射线与法线夹角
float mainAngle = reflectAngle * smoothness; //粗糙反射线平均方向与法线夹角
Vector3 axisTemp = Mathf.Abs(Vector3.Dot(faceNormal, Vector3.up)) > 0.9f ? Vector3.left : Vector3.up;
Vector3 axis0 = Vector3.Cross(faceNormal, axisTemp);//任意垂直于faceNormal的方向
Vector3 axis2 = -Vector3.Cross(reflectDir, faceNormal);
if (axis2.sqrMagnitude == 0)
{
axis2 = axis0;
}
float shininess = Mathf.Pow(8192, smoothness);
Quaternion finalRot = Quaternion.AngleAxis(UnityEngine.Random.Range(0f, 360f), faceNormal);
for (int i = 0; i < num; i++)
{
float angle0 = Mathf.Acos(Mathf.Pow(1 - HaltonTool.Halton2(i, 0f, 1f) * (shininess + 1) / (shininess + 2), 1 / (shininess + 1)));
angle0 *= Mathf.PI * 0.5f;//看起来上面公式的结果范围是0～1，所以加上这个修正一下，不知道原因
Vector3 dir0 = Quaternion.AngleAxis(angle0 * Mathf.Rad2Deg, axis0) * faceNormal;
Vector3 dir1 = Quaternion.AngleAxis(HaltonTool.Halton3(i, 0f, 360f), faceNormal) * dir0;
Vector3 dir2 = Quaternion.AngleAxis(mainAngle * Mathf.Rad2Deg, axis2) * dir1;
rlt[i] = dir2;
//Debug.DrawLine(dir2 + Vector3.up * 5, dir2 + Vector3.up * 5 + dir2 * 0.02f, Color.red, 10000);
}
return(rlt);
}
//尝试瞎凑的公式
public static Vector3[] GetRandomDirs_BRDF(Vector3 faceNormal, Vector3 reflectDir, float smoothness, int num)
{
Vector3[] rlt = new Vector3[num];
//Vector3 mainOutDir = Vector3.Lerp(faceNormal, reflectDir, smoothness).normalized;
float reflectAngle = Mathf.Acos(Vector3.Dot(reflectDir, faceNormal)); //镜面反射线与法线夹角
float mainAngle = reflectAngle * smoothness; //粗糙反射线平均方向与法线夹角
float distributionAngle = (Mathf.PI * 0.5f * (1 - smoothness));
Vector3 axisTemp = Mathf.Abs(Vector3.Dot(faceNormal, Vector3.up)) > 0.9f ? Vector3.left : Vector3.up;
Vector3 axis0 = Vector3.Cross(faceNormal, axisTemp);//任意垂直于faceNormal的方向
Vector3 axis2 = -Vector3.Cross(reflectDir, faceNormal);
if (axis2.sqrMagnitude == 0)
{
axis2 = axis0;
}
Quaternion finalRot = Quaternion.AngleAxis(UnityEngine.Random.Range(0f, 360f), faceNormal);
for (int i = 0; i < num; i++)
{
float angle0 = Mathf.Asin(Mathf.Sqrt(HaltonTool.Halton2(i, 0f, 1f))) * distributionAngle / (Mathf.PI / 2);
Vector3 dir0 = Quaternion.AngleAxis(angle0 * Mathf.Rad2Deg, axis0) * faceNormal;
Vector3 dir1 = Quaternion.AngleAxis(HaltonTool.Halton3(i, 0f, 360f), faceNormal) * dir0;
Vector3 dir2 = Quaternion.AngleAxis(mainAngle * Mathf.Rad2Deg, axis2) * dir1;
rlt[i] = dir2;
//Debug.DrawLine(dir2 + Vector3.up * 5, dir2 + Vector3.up * 5 + dir2 * 0.02f, Color.red, 10000);
}
return(rlt);
}
public static Vector3[] GetRandomDirs(Vector3 faceNormal, int num)
{
Vector3[] rlt = new Vector3[num];
Vector3 axisTemp = Mathf.Abs(Vector3.Dot(faceNormal, Vector3.up)) > 0.9f ? Vector3.left : Vector3.up;
Vector3 axis0 = Vector3.Cross(faceNormal, axisTemp);
for (int i = 0; i < num; i++)
{
float angle0 = Mathf.Acos(HaltonTool.Halton2(i, 0f, 1f)) * Mathf.Rad2Deg;
Vector3 dir = Quaternion.AngleAxis(angle0, axis0) * faceNormal;
Quaternion finalRot = Quaternion.AngleAxis(UnityEngine.Random.Range(0f, 360f), faceNormal);
dir = finalRot * dir;
//Debug.DrawLine(dir + Vector3.up * 5, dir + Vector3.up * 5 + dir * 0.02f, Color.red, 10000);
rlt[i] = dir;
}
return(rlt);
}
public static Vector3[] GetRandomDirs_RoundProj(Vector3 faceNormal, int num)
{
Vector3[] rlt = new Vector3[num];
Vector3 axisTemp = Mathf.Abs(Vector3.Dot(faceNormal, Vector3.up)) > 0.9f ? Vector3.left : Vector3.up;
Vector3 axis0 = Vector3.Cross(faceNormal, axisTemp);
Quaternion finalRot = Quaternion.AngleAxis(UnityEngine.Random.Range(0f, 360f), faceNormal);
for (int i = 0; i < num; i++)
{
float lenght0 = Mathf.Sqrt(HaltonTool.Halton2(i, 0f, 1f));
//float lenght0 = Mathf.Sin(Mathf.PI * 0.5f * Mathf.Sqrt(HaltonTool.Halton2(i, 0f, 1f)));
Vector3 pos0 = axis0 * lenght0;
Vector3 pos1 = Quaternion.AngleAxis(HaltonTool.Halton3(i, 0f, 360f), faceNormal) * pos0;
Vector3 dir = pos1 + faceNormal * (Mathf.Sqrt(1 - lenght0 * lenght0));
//Debug.DrawLine(dir + Vector3.up * 5, dir + Vector3.up * 5 + faceNormal * 0.02f, Color.red, 10000);
dir = finalRot * dir;
rlt[i] = dir;
}
return(rlt);
}
//http://www.klayge.org/?p=3006
public static Vector3[] GetRandomDirs_BlinnPhong_Importance2(Vector3 faceNormal, Vector3 reflectDir, float smoothness, int num)
{
Vector3[] rlt = new Vector3[num];
Vector3 w = Vector3.Lerp(faceNormal, reflectDir, smoothness).normalized;
Vector3 u = Vector3.Cross(new Vector3(w.y, w.z, w.x), w);
Vector3 v = Vector3.Cross(w, u);
float shininess = Mathf.Pow(8192, smoothness);
for (int i = 0; i < num; i++)
{
float a = Mathf.Acos(Mathf.Pow(1 - HaltonTool.Halton2(i, 0f, 1f) * (shininess + 1) / (shininess + 2), 1 / (shininess + 1)));
a *= Mathf.PI * 0.5f;//看起来上面公式的结果范围是0～1，所以加上这个修正一下，不知道原因
float phi = HaltonTool.Halton3(i, 0f, Mathf.PI * 2);
rlt[i] = (u * Mathf.Cos(phi) + v * Mathf.Sin(phi)) * Mathf.Sin(a) + w * Mathf.Cos(a);
//Debug.DrawLine(rlt[i] + Vector3.up * 5, rlt[i] + Vector3.up * 5 + rlt[i] * 0.02f, Color.red, 10000);
}
return(rlt);
}
public void Init()
{
Instance = this;
updateProgress(0);
HaltonTool.InitHaltonSequence();
Debug.Log("Start Time : " + Time.realtimeSinceStartup);
scene = new SimpleScene();
RayTrace.Init();
SimpleMaterial.textures.Clear();
scene.lights = GameObject.FindObjectsOfType <Light>();
Camera cam = GetComponent <Camera>();
if (cam)
{
MeshRenderer[] renderers = GameObject.FindObjectsOfType <MeshRenderer>();
foreach (MeshRenderer r in renderers)
{
bool isLayerVisible = ((1 << r.gameObject.layer) & cam.cullingMask) != 0;
if (r.isVisible && isLayerVisible)
{
MeshFilter filter = r.gameObject.GetComponent <MeshFilter>();
if (filter && filter.sharedMesh)
{
for (int i = 0; i < filter.sharedMesh.subMeshCount; i++)
{
Mesh mesh = filter.sharedMesh;
int[] triangles = filter.sharedMesh.GetTriangles(i);
RayTrace.AddMesh(filter.gameObject.transform, mesh.vertexCount, triangles.Length, mesh.vertices, triangles, 1);
SimpleModel model = new SimpleModel(r.gameObject.transform, filter.sharedMesh, i, r.sharedMaterials[i]);
model.lights = RayTraceTool.GetActivityLights(r, scene);
scene.models.Add(model);
}
}
}
}
Terrain[] terrains = GameObject.FindObjectsOfType <Terrain>();
foreach (Terrain terrain in terrains)
{
bool isLayerVisible = ((1 << terrain.gameObject.layer) & cam.cullingMask) != 0;
if (terrain.gameObject.activeInHierarchy && isLayerVisible)
{
int w = terrain.terrainData.heightmapWidth;
int h = terrain.terrainData.heightmapHeight;
float realWidth = terrain.terrainData.size.x * (1 + 1f / w);
float realHeight = terrain.terrainData.size.z * (1 + 1f / h);
float[,] heights = terrain.terrainData.GetHeights(0, 0, w, h);
Vector3[] vertices = new Vector3[w * h];
Vector2[] uvs = new Vector2[vertices.Length];
Vector3[] normals = new Vector3[vertices.Length];
int[] triangles = new int[(w - 1) * (h - 1) * 2 * 3];
for (int i = 0; i < w; i++)
{
for (int j = 0; j < h; j++)
{
Vector3 pos = new Vector3(i * realWidth / w, heights[j, i] * terrain.terrainData.size.y, j * realHeight / h);
vertices[j * w + i] = pos;
uvs[j * w + i] = new Vector2(i / (float)w, j / (float)h);
normals[j * w + i] = terrain.terrainData.GetInterpolatedNormal(i / (float)w, j / (float)h);
}
}
for (int i = 0; i < w - 1; i++)
{
for (int j = 0; j < h - 1; j++)
{
int index = (j * (w - 1) + i) * 6;
triangles[index + 0] = (i + 0) + (j + 0) * w;
triangles[index + 1] = (i + 1) + (j + 1) * w;
triangles[index + 2] = (i + 1) + (j + 0) * w;
triangles[index + 3] = (i + 0) + (j + 0) * w;
triangles[index + 4] = (i + 0) + (j + 1) * w;
triangles[index + 5] = (i + 1) + (j + 1) * w;
}
}
RayTrace.AddMesh(terrain.transform, vertices.Length, triangles.Length, vertices, triangles, 1);
SimpleModel model = new SimpleModel();
model.mesh = new SimpleMesh(triangles, uvs, vertices, normals);
model.material = new SimpleTerrainMaterial(terrain.terrainData);
model.rst = new RayTrace.RST(terrain.transform.rotation, terrain.transform.lossyScale, terrain.transform.position);
model.lights.AddRange(scene.lights);
scene.models.Add(model);
}
}
}
RayTrace.Commit();
texture = new Texture2D(width, height, TextureFormat.ARGB32, true);
//viewResult.sharedMaterial.mainTexture = texture;
}
