static void SmoothGaussianAdhesion(IvyRoot root)
{
//evolve a gaussian filter over the adhesion vectors, but only if it's not growing anymore
var e = Vector3.zero;
var tmpAdhesion = Vector3.zero;
for (int g = 0; g < 3; ++g)
{
smoothedAdhesionList.Clear(); // reuse allocation in smoothPoints
for (int n = 0; n < root.nodes.Count; n++)
{
e = Vector3.zero;
for (int i = -5; i <= 5; ++i)
{
tmpAdhesion = root.nodes[Mathf.Clamp(n + 1, 0, root.nodes.Count - 1)].c;
e += tmpAdhesion * gaussianFilter[i + 5];
}
smoothedAdhesionList.Add(e / 56.0f);
}
for (int i = 0; i < root.nodes.Count; i++)
{
root.nodes[i].c = smoothedAdhesionList[i];
}
}
}
public static void ForceIvyGrowth(IvyGraph graph, IvyProfile ivyProfile, Vector3 newPos, Vector3 newNormal)
{
newPos -= graph.seedPos; // convert to local space
var closestRoot = graph.roots[0];
var lastNode = closestRoot.nodes[closestRoot.nodes.Count - 1];
var growVector = newPos - lastNode.p;
var newNode = new IvyNode();
newNode.p = newPos;
newNode.g = (0.5f * lastNode.g + 0.5f * growVector.normalized).normalized;
newNode.c = -newNormal;
newNode.s = lastNode.s + growVector.magnitude;
newNode.cS = lastNode.cS + growVector.magnitude;
newNode.fS = 0f;
newNode.cl = true;
closestRoot.nodes.Add(newNode);
closestRoot.useCachedBranchData = false;
closestRoot.useCachedLeafData = false;
var cache = IvyRoot.GetMeshCacheFor(closestRoot);
cache.debugLineSegmentsList.Add(lastNode.p + graph.seedPos);
cache.debugLineSegmentsList.Add(newPos + graph.seedPos);
cache.debugLineSegmentsArray = cache.debugLineSegmentsList.ToArray();
if (graph.generateMeshDuringGrowth)
{
IvyMesh.GenerateMesh(graph, ivyProfile);
}
}
/** initialize a new ivy root */
public void seed(Vector3 seedPos)
{
reset();
roots.Clear();
IvyNode tmpNode = new IvyNode();
tmpNode.pos = seedPos;
tmpNode.primaryDir = new Vector3(0.0f, 1.0f, 0.0f);
tmpNode.adhesionVector = new Vector3(0.0f, 0.0f, 0.0f);
tmpNode.length = 0.0f;
tmpNode.floatingLength = 0.0f;
tmpNode.climb = true;
IvyRoot tmpRoot = new IvyRoot();
tmpRoot.nodes.Add(tmpNode);
tmpRoot.alive = true;
tmpRoot.parents = 0;
roots.Add(tmpRoot);
}
static Dictionary <Vector3, int> GetAllSamplePosAlongRoot(IvyRoot root, float leafSize)
{
leafList.Clear();
float rootEndLength = root.nodes[root.nodes.Count - 1].s + Mathf.Epsilon;
for (float pointer = leafSize; pointer <= rootEndLength; pointer += leafSize)
{
AddLeafPosAlongRoot(root, pointer);
}
return(leafList);
}
public static void RegenerateDebugLines(Vector3 seedPos, IvyRoot root)
{
root.debugLineSegmentsArray = new Vector3[(root.nodes.Count - 1) * 2];
var cache = IvyRoot.GetMeshCacheFor(root);
int nodeCounter = 0;
for (int i = 0; i < cache.debugLineSegmentsArray.Length; i += 2)
{
cache.debugLineSegmentsArray[i] = root.nodes[nodeCounter].p + seedPos;
cache.debugLineSegmentsArray[i + 1] = root.nodes[nodeCounter + 1].p + seedPos;
nodeCounter++;
}
}
static bool TryGrowIvyBranch(IvyGraph graph, IvyProfile ivyProfile, IvyRoot root, IvyNode fromNode, float forceMinLength = -1f)
{
//weight depending on ratio of node length to total length
float weight = 1f; //Mathf.PerlinNoise( fromNode.localPos.x + fromNode.lengthCumulative, fromNode.length + fromNode.localPos.y + fromNode.localPos.z); // - ( Mathf.Cos( fromNode.length / root.nodes[root.nodes.Count-1].length * 2.0f * Mathf.PI) * 0.5f + 0.5f );
var nearbyRootCount = graph.roots.Where(r => (r.nodes[0].p - fromNode.p).sqrMagnitude < ivyProfile.ivyStepDistance * ivyProfile.ivyStepDistance).Count();
if (forceMinLength <= 0f)
{
if (graph.roots.Count >= ivyProfile.maxBranchesTotal ||
nearbyRootCount > ivyProfile.branchingProbability * 2.5f ||
root.childCount > ivyProfile.branchingProbability * 3.5f ||
root.nodes.Count < 3 ||
root.parents > ivyProfile.branchingProbability * 9f ||
ivyProfile.maxLength - fromNode.cS < ivyProfile.minLength ||
Random.value * Mathf.Clamp(weight, 0f, 1f - ivyProfile.branchingProbability) > ivyProfile.branchingProbability
)
{
return(false);
}
}
//new ivy node
IvyNode newRootNode = new IvyNode();
newRootNode.p = fromNode.p;
newRootNode.g = Vector3.Lerp(fromNode.g, Vector3.up, 0.5f).normalized;
newRootNode.c = fromNode.c;
newRootNode.s = 0.0f;
newRootNode.cS = forceMinLength > 0f ? 0f : fromNode.cS;
newRootNode.fS = forceMinLength > 0f ? 0f : fromNode.fS;
newRootNode.cl = true;
//new ivy root
IvyRoot newRoot = new IvyRoot();
newRoot.nodes.Add(newRootNode);
newRoot.isAlive = true;
newRoot.parents = root.parents + 1;
newRoot.forceMinLength = forceMinLength;
graph.roots.Add(newRoot);
root.childCount++;
return(true);
}
public static IvyGraph SeedNewIvyGraph(IvyProfile ivyProfile, Vector3 seedPos, Vector3 primaryGrowDir, Vector3 adhesionVector, Transform root, bool generateMeshPreview = false)
{
var graph = new IvyGraph();
graph.roots.Clear();
graph.seedPos = seedPos;
graph.seedNormal = adhesionVector;
graph.generateMeshDuringGrowth = generateMeshPreview;
graph.rootBehavior = root;
IvyNode tmpNode = new IvyNode();
tmpNode.p = Vector3.zero; //seedPos;
tmpNode.g = primaryGrowDir;
tmpNode.c = adhesionVector;
tmpNode.s = 0.0f;
tmpNode.cS = 0f;
tmpNode.fS = 0.0f;
tmpNode.cl = true;
IvyRoot tmpRoot = new IvyRoot();
tmpRoot.nodes.Add(tmpNode);
tmpRoot.isAlive = true;
graph.isGrowing = true;
tmpRoot.parents = 0;
graph.roots.Add(tmpRoot);
if (graph.generateMeshDuringGrowth)
{
IvyMesh.GenerateMesh(graph, ivyProfile);
#if UNITY_EDITOR
Undo.RegisterCreatedObjectUndo(graph.rootGO, "Hedera > Paint Ivy");
#endif
}
return(graph);
}
static void AddLeafPosAlongRoot(IvyRoot ivyRoot, float distance)
{
int startNodeIndex = 0, endNodeIndex = -1;
for (int i = 0; i < ivyRoot.nodes.Count; i++)
{
if (ivyRoot.nodes[i].s <= distance + Mathf.Epsilon)
{
startNodeIndex = i;
}
if (endNodeIndex < 0 && ivyRoot.nodes[i].s >= distance - Mathf.Epsilon)
{
endNodeIndex = i;
}
}
float t = Mathf.InverseLerp(ivyRoot.nodes[startNodeIndex].s, ivyRoot.nodes[endNodeIndex].s, distance);
leafList.Add(
Vector3.Lerp(ivyRoot.nodes[startNodeIndex].p, ivyRoot.nodes[endNodeIndex].p, t),
startNodeIndex
);
}
static void CheckMeshDataAsset(ref long meshID, IvyDataAsset myAsset, IvyProfile.MeshCompression meshCompress)
{
if (meshID == 0)
{
meshID = IvyRoot.GetRandomLong();
}
if (!myAsset.meshList.ContainsKey(meshID) || myAsset.meshList[meshID] == null)
{
var newMesh = new Mesh();
#if UNITY_EDITOR
MeshUtility.SetMeshCompression(newMesh, (ModelImporterMeshCompression)meshCompress);
AssetDatabase.AddObjectToAsset(newMesh, AssetDatabase.GetAssetPath(myAsset));
#endif
if (myAsset.meshList.ContainsKey(meshID) && myAsset.meshList[meshID] == null)
{
myAsset.meshList[meshID] = newMesh;
}
else
{
myAsset.meshList.Add(meshID, newMesh);
}
}
}
static bool GenerateMeshData(IvyGraph ivyGraph, IvyProfile ivyProfile, bool forceGeneration = false)
{
var p = ivyProfile;
//branches
foreach (var root in ivyGraph.roots)
{
var cache = IvyRoot.GetMeshCacheFor(root);
if (root.useCachedBranchData && !forceGeneration)
{
combinedTriangleIndices.Clear();
cache.triangles.ForEach(localIndex => combinedTriangleIndices.Add(localIndex + verticesAll.Count));
trianglesAll.AddRange(combinedTriangleIndices);
verticesAll.AddRange(cache.vertices);
texCoordsAll.AddRange(cache.texCoords);
continue;
}
root.useCachedBranchData = true;
//process only roots with more than one node
if (root.nodes.Count < 2)
{
continue;
}
cache.vertices.Clear();
cache.texCoords.Clear();
cache.triangles.Clear();
//branch diameter depends on number of parents AND branch taper
float local_ivyBranchDiameter = 1.0f / Mathf.Lerp(1f, 1f + root.parents, ivyProfile.branchTaper);
// smooth the line... which increases points a lot
allPoints = root.nodes.Select(node => node.p).ToList();
var useThesePoints = allPoints;
if (ivyProfile.branchSmooth > 1)
{
SmoothLineCatmullRomNonAlloc(allPoints, smoothPoints, ivyProfile.branchSmooth);
useThesePoints = smoothPoints;
}
// generate simplified points for each root, to make it less wavy AND save tris
if (!root.isAlive && ivyProfile.branchOptimize > 0f)
{
newPoints.Clear();
newPoints.AddRange(SimplificationHelpers.Simplify <Vector3>(
useThesePoints,
(vec1, vec2) => vec1 == vec2,
(vec) => vec.x,
(vec) => vec.y,
(vec) => vec.z,
ivyProfile.branchOptimize * ivyProfile.ivyStepDistance * 0.5f,
false
));
useThesePoints = newPoints;
}
// I'm not sure why there's this bug when we use Catmull Rom + line simplify, but let's do this hacky fix
// if ( ivyProfile.branchSmooth > 1 && ivyProfile.branchOptimize > 0f ) {
// useThesePoints.ForEach( delegate(Vector3 point) {
// if ( float.IsInfinity(point.x) ) {point.x = 0f;}
// if ( float.IsInfinity(point.y) ) {point.y = 0f;}
// if ( float.IsInfinity(point.z) ) {point.z = 0f;}
// } );
// }
for (int n = 0; n < useThesePoints.Count; n++)
{
if (verticesAll.Count >= 65531)
{
Debug.LogWarning("Hedera: ending branch generation early, reached ~65536 vertex limit on mesh " + ivyGraph.seedPos + "... but this could technically be solved in Unity 2017.3+ or later with 32-bit index formats for meshes? The exercise is left to the reader.");
break;
}
cache.meshSegments = n + 1;
//weight depending on ratio of node length to total length
float taper = 1f * n / useThesePoints.Count;
taper = Mathf.Lerp(1f, (1f - taper) * taper, ivyProfile.branchTaper);
//create trihedral vertices... TODO: let user specify how many sides?
Vector3 up = Vector3.down;
Vector3 basis = Vector3.Normalize(n < useThesePoints.Count - 1 ? useThesePoints[n + 1] - useThesePoints[n] : -(useThesePoints[n] - useThesePoints[n - 1]));
// Debug.DrawLine( newPoints[node+1] + ivyGraph.seedPos, newPoints[node] + ivyGraph.seedPos, Color.cyan, 5f, false);
int edges = 3; // TODO: finish this, make it configurable
float texV = (n % 2 == 0 ? 1f : 0.0f); // vertical UV tiling
for (int b = 0; b < edges; b++)
{
// generate vertices
if (b == 0)
{
branchVertBasis[b] = Vector3.Cross(up, basis).normalized *Mathf.Max(0.001f, local_ivyBranchDiameter * p.ivyBranchSize * taper) + useThesePoints[n];
}
else
{
branchVertBasis[b] = RotateAroundAxis(branchVertBasis[0], useThesePoints[n], basis, 6.283f * b / edges);
}
cache.vertices.Add(branchVertBasis[b]);
// generate UVs
cache.texCoords.Add(new Vector2(1f * b / (edges - 1), texV));
// add triangles
// AddTriangle(root, 4, 1, 5);
// AddTriangle(root, 5, 1, 2);
// TODO: finish this
}
if (n == 0) // start cap
{
if (taper > 0f)
{
AddTriangle(cache, 1, 2, 3);
}
continue;
}
AddTriangle(cache, 4, 1, 5);
AddTriangle(cache, 5, 1, 2);
AddTriangle(cache, 5, 2, 6);
AddTriangle(cache, 6, 2, 3);
AddTriangle(cache, 6, 3, 1);
AddTriangle(cache, 6, 1, 4);
if (n == useThesePoints.Count - 1 && taper > 0f) // end cap
{
AddTriangle(cache, 3, 2, 1);
}
}
combinedTriangleIndices.Clear();
cache.triangles.ForEach(localIndex => combinedTriangleIndices.Add(localIndex + verticesAll.Count));
trianglesAll.AddRange(combinedTriangleIndices);
verticesAll.AddRange(cache.vertices);
texCoordsAll.AddRange(cache.texCoords);
}
if (ivyProfile.ivyLeafSize <= 0.001f || ivyProfile.leafProbability <= 0.001f)
{
return(true);
}
//create leafs
allLeafPoints.Clear();
foreach (var root in ivyGraph.roots)
{
// don't bother on small roots
if (root.nodes.Count <= 2)
{
root.useCachedLeafData = false;
continue;
}
var cache = IvyRoot.GetMeshCacheFor(root);
// use cached mesh data for leaves only if (a) we're supposed to, and (b) if not using vertex colors OR vertex colors seem valid
if (root.useCachedLeafData && !forceGeneration && (!ivyProfile.useVertexColors || cache.leafVertices.Count == cache.leafVertexColors.Count))
{
combinedTriangleIndices.Clear();
cache.leafTriangles.ForEach(index => combinedTriangleIndices.Add(index + leafVerticesAll.Count));
leafTrianglesAll.AddRange(combinedTriangleIndices);
allLeafPoints.AddRange(cache.leafPoints);
leafVerticesAll.AddRange(cache.leafVertices);
leafUVsAll.AddRange(cache.leafUVs);
if (ivyProfile.useVertexColors)
{
leafColorsAll.AddRange(cache.leafVertexColors);
}
continue;
}
root.useCachedLeafData = true;
cache.leafPoints.Clear();
cache.leafVertices.Clear();
cache.leafUVs.Clear();
cache.leafTriangles.Clear();
cache.leafVertexColors.Clear();
// simple multiplier, just to make it a more dense
for (int i = 0; i < 1; ++i)
{
var leafPositions = GetAllSamplePosAlongRoot(root, p.ivyLeafSize);
// for(int n=0; n<root.nodes.Count; n++)
foreach (var kvp in leafPositions)
{
if (leafVerticesAll.Count >= 65530)
{
Debug.LogWarning("Hedera: ending leaf generation early, reached ~65536 vertex limit on mesh " + ivyGraph.seedPos + "... but this could technically be solved in Unity 2017.3+ or later with 32-bit index formats for meshes? The exercise is left to the reader.");
break;
}
int n = kvp.Value;
Vector3 newLeafPos = kvp.Key;
var node = root.nodes[n];
// // do not generate a leaf on the first few nodes
// if ( n <= 1 ) { // || n >= root.nodes.Count
// continue;
// }
// probability of leaves on the ground is increased
float groundedness = Vector3.Dot(Vector3.down, node.c.normalized);
if (groundedness < -0.02f)
{
groundedness -= 0.1f;
groundedness *= 3f;
}
else
{
groundedness = (groundedness - 0.25f) * 0.5f;
}
groundedness *= ivyProfile.leafSunlightBonus * p.leafProbability;
// don't spawn a leaf on top of another leaf
bool badLeafPos = false;
float leafSqrSize = p.ivyLeafSize * p.ivyLeafSize * Mathf.Clamp(1f - p.leafProbability - groundedness, 0.01f, 2f);
for (int f = 0; f < allLeafPoints.Count; f++)
{
if (Vector3.SqrMagnitude(allLeafPoints[f] - newLeafPos) < leafSqrSize)
{
badLeafPos = true;
break;
}
}
if (badLeafPos)
{
continue;
}
IvyNode previousNode = root.nodes[Mathf.Max(0, n - 1)];
float randomSpreadHack = 0.25f;
if (n <= 1 || n == root.nodes.Count - 1)
{
randomSpreadHack = 0f;
}
// randomize leaf probability // guarantee a leaf on the first or last node
if ((Random.value + groundedness > 1f - p.leafProbability) || randomSpreadHack == 0f)
{
cache.leafPoints.Add(node.p);
allLeafPoints.Add(node.p);
//center of leaf quad
Vector3 up = (newLeafPos - previousNode.p).normalized;
Vector3 right = Vector3.Cross(up, node.c);
Vector3 center = newLeafPos - node.c.normalized * 0.05f + (up * Random.Range(-1f, 1f) + right * Random.Range(-1f, 1f)) * randomSpreadHack * p.ivyLeafSize;
//size of leaf
float sizeWeight = 1.5f - (Mathf.Abs(Mathf.Cos(2.0f * Mathf.PI)) * 0.5f + 0.5f);
float leafSize = p.ivyLeafSize * sizeWeight + Random.Range(-p.ivyLeafSize, p.ivyLeafSize) * 0.1f + (p.ivyLeafSize * groundedness);
leafSize = Mathf.Max(0.01f, leafSize);
Quaternion facing = node.c.sqrMagnitude < 0.001f ? Quaternion.identity : Quaternion.LookRotation(Vector3.Lerp(-node.c, Vector3.up, Mathf.Clamp01(0.68f - Mathf.Abs(groundedness)) * ivyProfile.leafSunlightBonus), Random.onUnitSphere);
AddLeafVertex(cache, center, new Vector3(-1f, 1f, 0f), leafSize, facing);
AddLeafVertex(cache, center, new Vector3(1f, 1f, 0f), leafSize, facing);
AddLeafVertex(cache, center, new Vector3(-1f, -1f, 0f), leafSize, facing);
AddLeafVertex(cache, center, new Vector3(1f, -1f, 0f), leafSize, facing);
cache.leafUVs.Add(new Vector2(1.0f, 1.0f));
cache.leafUVs.Add(new Vector2(0.0f, 1.0f));
cache.leafUVs.Add(new Vector2(1.0f, 0.0f));
cache.leafUVs.Add(new Vector2(0.0f, 0.0f));
if (ivyProfile.useVertexColors)
{
var randomColor = ivyProfile.leafVertexColors.Evaluate(Random.value);
cache.leafVertexColors.Add(randomColor);
cache.leafVertexColors.Add(randomColor);
cache.leafVertexColors.Add(randomColor);
cache.leafVertexColors.Add(randomColor);
}
// calculate normal of the leaf tri, and make it face outwards
// var normal = GetNormal(
// ivyGraph.leafVertices[ivyGraph.leafVertices.Count - 2],
// ivyGraph.leafVertices[ivyGraph.leafVertices.Count - 4],
// ivyGraph.leafVertices[ivyGraph.leafVertices.Count - 3]
// );
// if ( Vector3.Dot( normal, node.adhesionVector) < 0f) {
// AddLeafTriangle(ivyGraph, 2, 4, 3);
// AddLeafTriangle(ivyGraph, 3, 1, 2);
// } else {
AddLeafTriangle(cache, 1, 3, 4);
AddLeafTriangle(cache, 4, 2, 1);
// }
}
}
combinedTriangleIndices.Clear();
cache.leafTriangles.ForEach(index => combinedTriangleIndices.Add(index + leafVerticesAll.Count));
leafTrianglesAll.AddRange(combinedTriangleIndices);
leafVerticesAll.AddRange(cache.leafVertices);
leafUVsAll.AddRange(cache.leafUVs);
if (ivyProfile.useVertexColors)
{
leafColorsAll.AddRange(cache.leafVertexColors);
}
}
}
return(true);
}
public static void GrowIvyStep(IvyGraph graph, IvyProfile ivyProfile)
{
// if there are no longer any live roots, then we're dead
if (graph.isGrowing)
{
graph.isGrowing = graph.roots.Where(root => root.isAlive).Count() > 0;
}
if (!graph.isGrowing)
{
return;
}
//lets grow
foreach (var root in graph.roots)
{
//process only roots that are alive
if (!root.isAlive)
{
continue;
}
IvyNode lastNode = root.nodes[root.nodes.Count - 1];
//let the ivy die, if the maximum float length is reached
if (lastNode.cS > ivyProfile.maxLength || (lastNode.cS > Mathf.Max(root.forceMinLength, ivyProfile.minLength) && lastNode.fS > ivyProfile.maxFloatLength))
{
// Debug.LogFormat("root death! cum dist: {0:F2}, floatLength {1:F2}", lastNode.lengthCumulative, lastNode.floatingLength);
root.isAlive = false;
SmoothGaussianAdhesion(root);
continue;
}
//grow vectors: primary direction, random influence, and adhesion of scene objectss
//primary vector = weighted sum of previous grow vectors plus a little bit upwards
Vector3 primaryVector = Vector3.Normalize(lastNode.g * 2f + Vector3.up);
//random influence plus a little upright vector
Vector3 exploreVector = lastNode.p - root.nodes[0].p;
if (exploreVector.magnitude > 1f)
{
exploreVector = exploreVector.normalized;
}
exploreVector *= Mathf.PingPong(root.nodes[0].p.sqrMagnitude * root.parents + lastNode.cS * 0.69f, 1f);
Vector3 randomVector = (Random.onUnitSphere * 0.5f + exploreVector).normalized;
//adhesion influence to the nearest triangle = weighted sum of previous adhesion vectors
Vector3 adhesionVector = ComputeAdhesion(lastNode.p + graph.seedPos, ivyProfile);
if (adhesionVector.sqrMagnitude <= 0.01f)
{
adhesionVector = lastNode.c;
}
//compute grow vector
Vector3 growVector = ivyProfile.ivyStepDistance *
Vector3.Normalize(
primaryVector * ivyProfile.primaryWeight
+ randomVector * Mathf.Max(0.01f, ivyProfile.randomWeight)
+ adhesionVector * ivyProfile.adhesionWeight
);
//gravity influence
Vector3 gravityVector = ivyProfile.ivyStepDistance * Vector3.down * ivyProfile.gravityWeight;
//gravity depends on the floating length
gravityVector *= Mathf.Pow(lastNode.fS / ivyProfile.maxFloatLength, 0.7f);
//next possible ivy node
//climbing state of that ivy node, will be set during collision detection
bool climbing = false;
//compute position of next ivy node
Vector3 newPos = lastNode.p + growVector + gravityVector;
//combine alive state with result of the collision detection, e.g. let the ivy die in case of a collision detection problem
Vector3 adhesionFromRaycast = adhesionVector;
// convert newPos to world position, just for the collision calc
newPos += graph.seedPos;
root.isAlive = root.isAlive && ComputeCollision(0.01f, lastNode.p + graph.seedPos, ref newPos, ref climbing, ref adhesionFromRaycast, ivyProfile.collisionMask);
newPos -= graph.seedPos;
//update grow vector due to a changed newPos
growVector = newPos - lastNode.p - gravityVector;
// +graph.seedPos to convert back to world space
var cache = IvyRoot.GetMeshCacheFor(root);
cache.debugLineSegmentsList.Add(lastNode.p + graph.seedPos);
cache.debugLineSegmentsList.Add(newPos + graph.seedPos);
// cache line segments
cache.debugLineSegmentsArray = cache.debugLineSegmentsList.ToArray();
//create next ivy node
IvyNode newNode = new IvyNode();
newNode.p = newPos;
newNode.g = (0.5f * lastNode.g + 0.5f * growVector.normalized).normalized;
newNode.c = adhesionVector; //Vector3.Lerp(adhesionVector, adhesionFromRaycast, 0.5f);
newNode.s = lastNode.s + (newPos - lastNode.p).magnitude;
newNode.cS = lastNode.cS + (newPos - lastNode.p).magnitude;
newNode.fS = climbing ? 0.0f : lastNode.fS + (newPos - lastNode.p).magnitude;
newNode.cl = climbing;
root.nodes.Add(newNode);
root.useCachedBranchData = false;
root.useCachedLeafData = false;
if (!root.isAlive)
{
SmoothGaussianAdhesion(root);
}
var randomNode = root.nodes[Random.Range(0, root.nodes.Count)];
if (TryGrowIvyBranch(graph, ivyProfile, root, randomNode))
{
break;
}
}
}
/** one single grow iteration */
public void grow()
{
//parameters that depend on the scene object bounding sphere
float local_ivySize = IvyManager.SceneObjMesh.boundingSphereRadius * ivySize;
float local_maxFloatLength = IvyManager.SceneObjMesh.boundingSphereRadius * maxFloatLength;
//normalize weights of influence
float sum = primaryWeight + randomWeight + adhesionWeight;
primaryWeight /= sum;
randomWeight /= sum;
adhesionWeight /= sum;
//lets grow
foreach (var root in roots)
{
//process only roots that are alive
if (!root.alive)
{
continue;
}
IvyNode lastnode = root.nodes[root.nodes.Count - 1];
//let the ivy die, if the maximum float length is reached
if (lastnode.floatingLength > local_maxFloatLength)
{
root.alive = false;
}
//grow vectors: primary direction, random influence, and adhesion of scene objectss
//primary vector = weighted sum of previous grow vectors
Vector3 primaryVector = lastnode.primaryDir;
//random influence plus a little upright vector
Vector3 randomVector = (new Vector3(Random.Range(-0.5f, 0.5f), Random.Range(-0.5f, 0.5f), Random.Range(-0.5f, 0.5f)) + new Vector3(0.0f, 0.2f, 0.0f)).normalized;
//adhesion influence to the nearest triangle = weighted sum of previous adhesion vectors
Vector3 adhesionVector = computeAdhesion(lastnode.pos);
//compute grow vector
Vector3 growVector = local_ivySize * (primaryVector * primaryWeight + randomVector * randomWeight + adhesionVector * adhesionWeight);
//gravity influence
//compute gravity vector
Vector3 gravityVector = local_ivySize * new Vector3(0.0f, -1.0f, 0.0f) * gravityWeight;
//gravity depends on the floating length
gravityVector *= Mathf.Pow(lastnode.floatingLength / local_maxFloatLength, 0.7f);
//next possible ivy node
//climbing state of that ivy node, will be set during collision detection
bool climbing = false;
//compute position of next ivy node
Vector3 newPos = lastnode.pos + growVector + gravityVector;
//combine alive state with result of the collision detection, e.g. let the ivy die in case of a collision detection problem
root.alive = root.alive && computeCollision(lastnode.pos, ref newPos, ref climbing);
//update grow vector due to a changed newPos
growVector = newPos - lastnode.pos - gravityVector;
//create next ivy node
IvyNode tmpNode = new IvyNode();
tmpNode.pos = newPos;
tmpNode.primaryDir = (0.5f * lastnode.primaryDir + 0.5f * growVector.normalized).normalized;
tmpNode.adhesionVector = adhesionVector;
tmpNode.length = lastnode.length + (newPos - lastnode.pos).magnitude;
tmpNode.floatingLength = climbing ? 0.0f : lastnode.floatingLength + (newPos - lastnode.pos).magnitude;
tmpNode.climb = climbing;
root.nodes.Add(tmpNode);
}
//lets produce child ivys
foreach (var root in roots)
{
//process only roots that are alive
if (!root.alive)
{
continue;
}
//process only roots up to hierarchy level 3, results in a maximum hierarchy level of 4
if (root.parents > 3)
{
continue;
}
//add child ivys on existing ivy nodes
foreach (var node in root.nodes)
{
//weight depending on ratio of node length to total length
float weight = 1.0f - (Mathf.Cos(node.length / root.nodes[root.nodes.Count - 1].length * 2.0f * Mathf.PI) * 0.5f + 0.5f);
//random influence
float probability = Random.value;
if (probability * weight > branchingProbability)
{
//new ivy node
IvyNode tmpNode = new IvyNode();
tmpNode.pos = node.pos;
tmpNode.primaryDir = new Vector3(0.0f, 1.0f, 0.0f);
tmpNode.adhesionVector = new Vector3(0.0f, 0.0f, 0.0f);
tmpNode.length = 0.0f;
tmpNode.floatingLength = node.floatingLength;
tmpNode.climb = true;
//new ivy root
IvyRoot tmpRoot = new IvyRoot();
tmpRoot.nodes.Add(tmpNode);
tmpRoot.alive = true;
tmpRoot.parents = root.parents + 1;
roots.Add(tmpRoot);
//limit the branching to only one new root per iteration, so return
return;
}
}
}
}
public IvyGraph()
{
branchMeshID = IvyRoot.GetRandomLong();
leafMeshID = IvyRoot.GetRandomLong();
}
public static IvyRootMeshCache GetMeshCacheFor(IvyRoot root)
{
return(Get(root.cacheID));
}