private void Erode(int width, int height, float seaLevel, Overworld.MapData[,] heightMap, int numRains, int rainLength, int numRainSamples, float[,] buffer) { float remaining = 1.0f - Progress.Value - 0.2f; float orig = Progress.Value; for (int x = 0; x < width; x++) { for (int y = 0; y < height; y++) { buffer[x, y] = heightMap[x, y].Height; } } for (int i = 0; i < numRains; i++) { LoadingMessage = "Erosion " + i + "/" + numRains; Progress.Value = orig + remaining * ((float)i / (float)numRains); Vector2 currentPos = new Vector2(0, 0); Vector2 bestPos = currentPos; float bestHeight = 0.0f; for (int k = 0; k < numRainSamples; k++) { int randX = PlayState.Random.Next(1, width - 1); int randY = PlayState.Random.Next(1, height - 1); currentPos = new Vector2(randX, randY); float h = Overworld.GetHeight(buffer, currentPos); if (h > bestHeight) { bestHeight = h; bestPos = currentPos; } } currentPos = bestPos; const float erosionRate = 0.99f; Vector2 velocity = Vector2.Zero; for (int j = 0; j < rainLength; j++) { Vector2 g = Overworld.GetMinNeighbor(buffer, currentPos); float h = Overworld.GetHeight(buffer, currentPos); if (h < seaLevel || g.LengthSquared() < 1e-12) { break; } Overworld.MinBlend(Overworld.Map, currentPos, erosionRate * Overworld.GetValue(Overworld.Map, currentPos, Overworld.ScalarFieldType.Erosion), Overworld.ScalarFieldType.Erosion); velocity = 0.1f * g + 0.7f * velocity + 0.2f * MathFunctions.RandVector2Circle(); currentPos += velocity; } } }