private void BuildOffsetShape(TerrainMeshData meshData, MeshRegion region, GradientWrapper gradient,
Rectangle2d rect, float colorNoiseFreq, float deepLevel)
{
foreach (var contour in region.Contours)
{
var length = contour.Count;
for (int i = 0; i < length; i++)
{
var v2DIndex = i == (length - 1) ? 0 : i + 1;
var p1 = new Vector2d((float)contour[i].X, (float)contour[i].Y);
var p2 = new Vector2d((float)contour[v2DIndex].X, (float)contour[v2DIndex].Y);
// check whether two points are on cell rect
if (rect.IsOnBorder(p1) && rect.IsOnBorder(p2))
{
continue;
}
var ele1 = _elevationProvider.GetElevation(p1);
var ele2 = _elevationProvider.GetElevation(p2);
var firstColor = GradientUtils.GetColor(gradient,
new Vector3((float)p1.X, ele1, (float)p1.Y), colorNoiseFreq);
var secondColor = GradientUtils.GetColor(gradient,
new Vector3((float)p2.X, ele1 - deepLevel, (float)p2.Y), colorNoiseFreq);
meshData.AddTriangle(
new Vector3((float)p1.X, ele1, (float)p1.Y),
new Vector3((float)p2.X, ele2 - deepLevel, (float)p2.Y),
new Vector3((float)p2.X, ele2, (float)p2.Y),
firstColor);
meshData.AddTriangle(
new Vector3((float)p1.X, ele1 - deepLevel, (float)p1.Y),
new Vector3((float)p2.X, ele2 - deepLevel, (float)p2.Y),
new Vector3((float)p1.X, ele1, (float)p1.Y),
secondColor);
}
}
}
private void AddTriangle(Rule rule, TerrainMeshData meshData, Triangle triangle, GradientWrapper gradient,
float eleNoiseFreq, float colorNoiseFreq, float yOffset = 0)
{
var useEleNoise = Math.Abs(eleNoiseFreq) > 0.0001;
var v0 = GetVertex(triangle.GetVertex(0), eleNoiseFreq, useEleNoise, yOffset);
var v1 = GetVertex(triangle.GetVertex(1), eleNoiseFreq, useEleNoise, yOffset);
var v2 = GetVertex(triangle.GetVertex(2), eleNoiseFreq, useEleNoise, yOffset);
var triangleColor = GradientUtils.GetColor(gradient, v0, colorNoiseFreq);
meshData.AddTriangle(v0, v1, v2, triangleColor);
}