public static MeshData GenerateTerrainMesh(float[,] terrainFormattedHeightMapValues, MapConfiguration mapConfiguration, int levelOfDetail)
{
int skipIncrement = (levelOfDetail == 0) ? 1 : levelOfDetail * 2;
int numVertsPerLine = mapConfiguration.numVertsPerLine;
Vector2 topLeft = new Vector2(-1, 1) * mapConfiguration.chunkWorldSize / 2f;
MeshData meshData = new MeshData(numVertsPerLine, skipIncrement);
int[,] vertexIndicesMap = new int[numVertsPerLine, numVertsPerLine];
int meshVertexIndex = 0;
int outOfMeshVertexIndex = -1;
for (int y = 0; y < numVertsPerLine; y++)
{
for (int x = 0; x < numVertsPerLine; x++)
{
bool isOutOfMeshVertex = y == 0 || y == numVertsPerLine - 1 || x == 0 || x == numVertsPerLine - 1;
bool isSkippedVertex = x > 2 && x < numVertsPerLine - 3 && y > 2 && y < numVertsPerLine - 3 && ((x - 2) % skipIncrement != 0 || (y - 2) % skipIncrement != 0);
if (isOutOfMeshVertex)
{
vertexIndicesMap [x, y] = outOfMeshVertexIndex;
outOfMeshVertexIndex--;
}
else if (!isSkippedVertex)
{
vertexIndicesMap [x, y] = meshVertexIndex;
meshVertexIndex++;
}
}
}
for (int y = 0; y < numVertsPerLine; y++)
{
for (int x = 0; x < numVertsPerLine; x++)
{
bool isSkippedVertex = x > 2 && x < numVertsPerLine - 3 && y > 2 && y < numVertsPerLine - 3 && ((x - 2) % skipIncrement != 0 || (y - 2) % skipIncrement != 0);
if (!isSkippedVertex)
{
bool isOutOfMeshVertex = y == 0 || y == numVertsPerLine - 1 || x == 0 || x == numVertsPerLine - 1;
bool isMeshEdgeVertex = (y == 1 || y == numVertsPerLine - 2 || x == 1 || x == numVertsPerLine - 2) && !isOutOfMeshVertex;
bool isMainVertex = (x - 2) % skipIncrement == 0 && (y - 2) % skipIncrement == 0 && !isOutOfMeshVertex && !isMeshEdgeVertex;
bool isEdgeConnectionVertex = (y == 2 || y == numVertsPerLine - 3 || x == 2 || x == numVertsPerLine - 3) && !isOutOfMeshVertex && !isMeshEdgeVertex && !isMainVertex;
int vertexIndex = vertexIndicesMap [x, y];
Vector2 percent = new Vector2(x - 1, y - 1) / (numVertsPerLine - 3);
Vector2 vertexPosition2D = topLeft + new Vector2(percent.x, -percent.y) * mapConfiguration.chunkWorldSize;
float height = terrainFormattedHeightMapValues [x, y];
if (isEdgeConnectionVertex)
{
bool isVertical = x == 2 || x == numVertsPerLine - 3;
int dstToMainVertexA = ((isVertical) ? y - 2 : x - 2) % skipIncrement;
int dstToMainVertexB = skipIncrement - dstToMainVertexA;
float dstPercentFromAToB = dstToMainVertexA / (float)skipIncrement;
Coord coordA = new Coord((isVertical) ? x : x - dstToMainVertexA, (isVertical) ? y - dstToMainVertexA : y);
Coord coordB = new Coord((isVertical) ? x : x + dstToMainVertexB, (isVertical) ? y + dstToMainVertexB : y);
float heightMainVertexA = terrainFormattedHeightMapValues [coordA.x, coordA.y];
float heightMainVertexB = terrainFormattedHeightMapValues [coordB.x, coordB.y];
height = heightMainVertexA * (1 - dstPercentFromAToB) + heightMainVertexB * dstPercentFromAToB;
EdgeConnectionVertexData edgeConnectionVertexData = new EdgeConnectionVertexData(vertexIndex, vertexIndicesMap [coordA.x, coordA.y], vertexIndicesMap [coordB.x, coordB.y], dstPercentFromAToB);
meshData.DeclareEdgeConnectionVertex(edgeConnectionVertexData);
}
meshData.AddVertex(new Vector3(vertexPosition2D.x, height, vertexPosition2D.y), percent, vertexIndex);
bool createTriangle = x < numVertsPerLine - 1 && y < numVertsPerLine - 1 && (!isEdgeConnectionVertex || (x != 2 && y != 2));
if (createTriangle)
{
int currentIncrement = (isMainVertex && x != numVertsPerLine - 3 && y != numVertsPerLine - 3) ? skipIncrement : 1;
int a = vertexIndicesMap [x, y];
int b = vertexIndicesMap [x + currentIncrement, y];
int c = vertexIndicesMap [x, y + currentIncrement];
int d = vertexIndicesMap [x + currentIncrement, y + currentIncrement];
meshData.AddTriangle(a, d, c);
meshData.AddTriangle(d, a, b);
}
}
}
}
meshData.BakeNormals(); // Called now because this code runs in a separate thread, not in the main thread. So the Normals are calculated and stored in the mesh before being used by the main thread.
return(meshData);
}
public void DeclareEdgeConnectionVertex(EdgeConnectionVertexData edgeConnectionVertexData)
{
edgeConnectionVertices [edgeConnectionVertexIndex] = edgeConnectionVertexData;
edgeConnectionVertexIndex++;
}
