private List <Vector3> GenerateTreePositions(Texture2D treeMap, VertexMultiTextured[] terrainVertices)
{
Color[] treeMapColors = new Color[treeMap.Width * treeMap.Height];
treeMap.GetData(treeMapColors);
int[ , ] noiseData = new int[treeMap.Width, treeMap.Height];
for (int x = 0; x < treeMap.Width; x++)
{
for (int y = 0; y < treeMap.Height; y++)
{
noiseData[x, y] = treeMapColors[y + x * treeMap.Height].R;
}
}
List <Vector3> treeList = new List <Vector3>();
Random random = new Random();
for (int x = 0; x < mTerrain.Width; x++)
{
for (int y = 0; y < mTerrain.Length; y++)
{
float terrainHeight = mTerrain.HeightAt(x, y);
if ((terrainHeight > 8) && (terrainHeight < 14))
{
float flatness = Vector3.Dot(terrainVertices[x + y * mTerrain.Width].Normal, new Vector3(0, 1, 0));
float minFlatness = (float)Math.Cos(MathHelper.ToRadians(15));
if (flatness > minFlatness)
{
float relx = (float)x / (float)mTerrain.Width;
float rely = (float)y / (float)mTerrain.Length;
float noiseValueAtCurrentPosition = noiseData[(int)(relx * treeMap.Width), (int)(rely * treeMap.Height)];
float treeDensity;
if (noiseValueAtCurrentPosition > 200)
{
treeDensity = 5;
}
else if (noiseValueAtCurrentPosition > 150)
{
treeDensity = 4;
}
else if (noiseValueAtCurrentPosition > 100)
{
treeDensity = 3;
}
else
{
treeDensity = 0;
}
for (int currDetail = 0; currDetail < treeDensity; currDetail++)
{
float rand1 = (float)random.Next(1000) / 1000.0f;
float rand2 = (float)random.Next(1000) / 1000.0f;
Vector3 treePos = new Vector3((float)x - rand1, 0, -(float)y - rand2);
treePos.Y = mTerrain.HeightAt(x, y);
treeList.Add(treePos);
}
}
}
}
}
return(treeList);
}
