Hello all.
I am attempting something quite challenging, in fact extremely challenging. I have done hours and hours of research and I am hoping someone here on the Unity forum will be able to help me with building a Procedural Planet generator.
First off, this is what I need to figure out.
Creating a Cube Sphere with 6 individual faces.
I would like to generate a procedural mesh of a cube mapped to a Sphere with 6 individual Child game objects meshes.
TOP surface.
BOTTOM surface.
FRONT surface.
BACK Surface.
LEFT Surface.
RIGHT Surface.
I know how to procedural generate a Cube Sphere from reading CatLike Turorials here:
[RequireComponent(typeof(MeshFilter), typeof(MeshRenderer))]
public class CubeSphere : MonoBehaviour {
public int gridSize;
public float radius = 1f;
private Mesh mesh;
private Vector3[] vertices;
private Vector3[] normals;
private Color32[] cubeUV;
private void Awake () {
Generate();
}
private void Generate () {
GetComponent<MeshFilter>().mesh = mesh = new Mesh();
mesh.name = "Procedural Sphere";
CreateVertices();
CreateTriangles();
CreateColliders();
}
private void CreateVertices () {
int cornerVertices = 8;
int edgeVertices = (gridSize + gridSize + gridSize - 3) * 4;
int faceVertices = (
(gridSize - 1) * (gridSize - 1) +
(gridSize - 1) * (gridSize - 1) +
(gridSize - 1) * (gridSize - 1)) * 2;
vertices = new Vector3[cornerVertices + edgeVertices + faceVertices];
normals = new Vector3[vertices.Length];
cubeUV = new Color32[vertices.Length];
int v = 0;
for (int y = 0; y <= gridSize; y++) {
for (int x = 0; x <= gridSize; x++) {
SetVertex(v++, x, y, 0);
}
for (int z = 1; z <= gridSize; z++) {
SetVertex(v++, gridSize, y, z);
}
for (int x = gridSize - 1; x >= 0; x--) {
SetVertex(v++, x, y, gridSize);
}
for (int z = gridSize - 1; z > 0; z--) {
SetVertex(v++, 0, y, z);
}
}
for (int z = 1; z < gridSize; z++) {
for (int x = 1; x < gridSize; x++) {
SetVertex(v++, x, gridSize, z);
}
}
for (int z = 1; z < gridSize; z++) {
for (int x = 1; x < gridSize; x++) {
SetVertex(v++, x, 0, z);
}
}
mesh.vertices = vertices;
mesh.normals = normals;
mesh.colors32 = cubeUV;
}
private void SetVertex (int i, int x, int y, int z) {
Vector3 v = new Vector3(x, y, z) * 2f / gridSize - Vector3.one;
normals[i] = v.normalized;
vertices[i] = normals[i] * radius;
cubeUV[i] = new Color32((byte)x, (byte)y, (byte)z, 0);
}
private void CreateTriangles () {
int[] trianglesZ = new int[(gridSize * gridSize) * 12];
int[] trianglesX = new int[(gridSize * gridSize) * 12];
int[] trianglesY = new int[(gridSize * gridSize) * 12];
int ring = (gridSize + gridSize) * 2;
int tZ = 0, tX = 0, tY = 0, v = 0;
for (int y = 0; y < gridSize; y++, v++) {
for (int q = 0; q < gridSize; q++, v++) {
tZ = SetQuad(trianglesZ, tZ, v, v + 1, v + ring, v + ring + 1);
}
for (int q = 0; q < gridSize; q++, v++) {
tX = SetQuad(trianglesX, tX, v, v + 1, v + ring, v + ring + 1);
}
for (int q = 0; q < gridSize; q++, v++) {
tZ = SetQuad(trianglesZ, tZ, v, v + 1, v + ring, v + ring + 1);
}
for (int q = 0; q < gridSize - 1; q++, v++) {
tX = SetQuad(trianglesX, tX, v, v + 1, v + ring, v + ring + 1);
}
tX = SetQuad(trianglesX, tX, v, v - ring + 1, v + ring, v + 1);
}
tY = CreateTopFace(trianglesY, tY, ring);
tY = CreateBottomFace(trianglesY, tY, ring);
mesh.subMeshCount = 3;
mesh.SetTriangles(trianglesZ, 0);
mesh.SetTriangles(trianglesX, 1);
mesh.SetTriangles(trianglesY, 2);
}
private int CreateTopFace (int[] triangles, int t, int ring) {
int v = ring * gridSize;
for (int x = 0; x < gridSize - 1; x++, v++) {
t = SetQuad(triangles, t, v, v + 1, v + ring - 1, v + ring);
}
t = SetQuad(triangles, t, v, v + 1, v + ring - 1, v + 2);
int vMin = ring * (gridSize + 1) - 1;
int vMid = vMin + 1;
int vMax = v + 2;
for (int z = 1; z < gridSize - 1; z++, vMin--, vMid++, vMax++) {
t = SetQuad(triangles, t, vMin, vMid, vMin - 1, vMid + gridSize - 1);
for (int x = 1; x < gridSize - 1; x++, vMid++) {
t = SetQuad(
triangles, t,
vMid, vMid + 1, vMid + gridSize - 1, vMid + gridSize);
}
t = SetQuad(triangles, t, vMid, vMax, vMid + gridSize - 1, vMax + 1);
}
int vTop = vMin - 2;
t = SetQuad(triangles, t, vMin, vMid, vTop + 1, vTop);
for (int x = 1; x < gridSize - 1; x++, vTop--, vMid++) {
t = SetQuad(triangles, t, vMid, vMid + 1, vTop, vTop - 1);
}
t = SetQuad(triangles, t, vMid, vTop - 2, vTop, vTop - 1);
return t;
}
private int CreateBottomFace (int[] triangles, int t, int ring) {
int v = 1;
int vMid = vertices.Length - (gridSize - 1) * (gridSize - 1);
t = SetQuad(triangles, t, ring - 1, vMid, 0, 1);
for (int x = 1; x < gridSize - 1; x++, v++, vMid++) {
t = SetQuad(triangles, t, vMid, vMid + 1, v, v + 1);
}
t = SetQuad(triangles, t, vMid, v + 2, v, v + 1);
int vMin = ring - 2;
vMid -= gridSize - 2;
int vMax = v + 2;
for (int z = 1; z < gridSize - 1; z++, vMin--, vMid++, vMax++) {
t = SetQuad(triangles, t, vMin, vMid + gridSize - 1, vMin + 1, vMid);
for (int x = 1; x < gridSize - 1; x++, vMid++) {
t = SetQuad(
triangles, t,
vMid + gridSize - 1, vMid + gridSize, vMid, vMid + 1);
}
t = SetQuad(triangles, t, vMid + gridSize - 1, vMax + 1, vMid, vMax);
}
int vTop = vMin - 1;
t = SetQuad(triangles, t, vTop + 1, vTop, vTop + 2, vMid);
for (int x = 1; x < gridSize - 1; x++, vTop--, vMid++) {
t = SetQuad(triangles, t, vTop, vTop - 1, vMid, vMid + 1);
}
t = SetQuad(triangles, t, vTop, vTop - 1, vMid, vTop - 2);
return t;
}
private static int
SetQuad (int[] triangles, int i, int v00, int v10, int v01, int v11) {
triangles[i] = v00;
triangles[i + 1] = triangles[i + 4] = v01;
triangles[i + 2] = triangles[i + 3] = v10;
triangles[i + 5] = v11;
return i + 6;
}
private void CreateColliders () {
gameObject.AddComponent<SphereCollider>();
}
// private void OnDrawGizmos () {
// if (vertices == null) {
// return;
// }
// for (int i = 0; i < vertices.Length; i++) {
// Gizmos.color = Color.black;
// Gizmos.DrawSphere(vertices[i], 0.1f);
// Gizmos.color = Color.yellow;
// Gizmos.DrawRay(vertices[i], normals[i]);
// }
// }
}
So obviously I need to create one script called PlanetGenerator and another script called Surface that generates the 6 individual face meshes together as a Sphere.
The script above has the TopFace and BottomFace. I just need the 4 other faces in order to create 6 individual child game objects.
Would someone be able to help me do this?