public MeshAttributes Generate()
{
int numVerts = horizontal * vertical * 6;
MeshAttributes mesh = new MeshAttributes
{
vertices = new Vector3[numVerts],
uv = new Vector2[numVerts],
triangles = Enumerable.Range(0, numVerts).ToArray <int>(),
normals = new Vector3[horizontal + 1],
normalIndex = new int[numVerts],
tangent = new Vector3[] { Vector3.up },
tangentIndex = Enumerable.Repeat <int>(0, numVerts).ToArray <int>()
};
//Generate Normals
GenerateNormals(mesh);
for (int y = 0; y < vertical; ++y)
{
for (int x = 0; x < horizontal; ++x)
{
int index = (y * horizontal + x) * 6;
GenerateQuad(mesh, x, y, index);
GenerateUv(mesh, x, y, index);
GenerateNormalIndex(mesh, x, index);
}
}
return(mesh);
}
private void GenerateQuad(MeshAttributes mesh, int x, int y, int index)
{
//Angle of the leftmost vertex
float angle = x * addTh;
//I could've used a vector3 and added to another y vector3
//These two values are more easily memoizable than the positions.
Vector2 positionXZ = GetXzPosition(angle);
Vector2 nextPositionXZ = GetXzPosition(angle + addTh);
float positionY = bottom + y * addY;
float nextPositionY = bottom + (y + 1) * addY;
Vector3 position = new Vector3(positionXZ.x, positionY, positionXZ.y);
Vector3 nextX = new Vector3(nextPositionXZ.x, positionY, nextPositionXZ.y);
Vector3 nextY = new Vector3(positionXZ.x, nextPositionY, positionXZ.y);
Vector3 nextXY = new Vector3(nextPositionXZ.x, nextPositionY, nextPositionXZ.y);
//Bottom triangle
mesh.vertices[index] = position;
mesh.vertices[index + 1] = nextY;
mesh.vertices[index + 2] = nextX;
//Top triangle
mesh.vertices[index + 3] = nextXY;
mesh.vertices[index + 4] = nextX;
mesh.vertices[index + 5] = nextY;
}
void GenerateNormals(MeshAttributes mesh)
{
for (int i = 0; i <= horizontal; ++i)
{
float t = ((float)i / (float)horizontal);
mesh.normals[i] = normalMultiplier * new Vector3(Mathf.Sin(PI_2 * t), 0.0f, Mathf.Cos(PI_2 * t));
}
}
private void GenerateNormalIndex(MeshAttributes mesh, int x, int index)
{
//Vertices 0,1 and 5 are to the left, and the rest are to the right
for (int i = 0; i < 6; ++i)
{
//More to the right
if (i >= 2 && i <= 4)
{
mesh.normalIndex[index + i] = x + 1;
}
//More to the left
else
{
mesh.normalIndex[index + i] = x;
}
}
}
//copied from PlaneGenerator
private void GenerateUv(MeshAttributes mesh, int x, int y, int index)
{
Vector2 position = new Vector2(addUv.x * x, addUv.y * y);
Vector2 nextU = position + addUv.x * Vector2.right;
Vector2 nextV = position + addUv.y * Vector2.up;
Vector2 nextUV = position + addUv;
//Bottom triangle
mesh.uv[index] = position;
mesh.uv[index + 1] = nextV;
mesh.uv[index + 2] = nextU;
//Top triangle
mesh.uv[index + 3] = nextUV;
mesh.uv[index + 4] = nextU;
mesh.uv[index + 5] = nextV;
}
private void GenerateUv(MeshAttributes mesh, int x, int y, int index)
{
Vector2 texCoord = new Vector2(addUv.x * x, addUv.y * y);
texCoord += textureLowerLeft;
Vector2 nextU = texCoord + addUv.x * Vector2.right;
Vector2 nextV = texCoord + addUv.y * Vector2.up;
Vector2 nextUV = texCoord + addUv;
//Bottom triangle
mesh.uv[index] = texCoord;
mesh.uv[index + 1] = nextV;
mesh.uv[index + 2] = nextU;
//Top triangle
mesh.uv[index + 3] = nextUV;
mesh.uv[index + 4] = nextU;
mesh.uv[index + 5] = nextV;
}
private void GenerateQuad(MeshAttributes mesh, int x, int y, int index)
{
Vector3 position = new Vector3(addPos.x * x, addPos.y * y, 0.0f);
position += lowerLeft;
Vector3 nextX = position + addPos.x * Vector3.right;
Vector3 nextY = position + addPos.y * Vector3.up;
Vector3 nextXY = position + addPos;
//Bottom triangle
mesh.vertices[index] = position;
mesh.vertices[index + 1] = nextY;
mesh.vertices[index + 2] = nextX;
//Top triangle
mesh.vertices[index + 3] = nextXY;
mesh.vertices[index + 4] = nextX;
mesh.vertices[index + 5] = nextY;
}
public Mesh Modulate(MeshAttributes mesh)
{
Mesh result = new Mesh();
int length = mesh.vertices.Length;
uvwAmplitudePos = new Vector3(
uvDisplacement.x * uvDistPos.x,
uvDisplacement.y * uvDistPos.y,
amplitude
);
uvAmplitudeTex = Vector2.Scale(uvDistTex, uvDisplacement);
for (int i = 0; i < length; ++i)
{
Vector3 normal = mesh.normals[mesh.normalIndex[i]];
//AGAIN, TANGENT IS UP BECAUSE THIS ARE LEFT HANDED COORDINATES!!
Vector3 tangent = mesh.tangent[mesh.tangentIndex[i]];
Vector3 bitangent = Vector3.Cross(normal, tangent);
Vector3 noise = CalculateNoise(mesh.vertices[i]);
float t = (mesh.vertices[i].y - vMin) / (vMax - vMin);
float vFactor = Mathf.Sin(Mathf.PI * t);
mesh.vertices[i] = ModulateVertex(mesh.vertices[i], noise, normal, bitangent, tangent, vFactor);
mesh.uv[i] = ModulateUv(mesh.uv[i], noise, vFactor);
}
result.vertices = mesh.vertices;
result.uv = mesh.uv;
result.triangles = mesh.triangles;
result.RecalculateNormals();
result.RecalculateTangents();
result.RecalculateBounds();
return(result);
}
