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TerrainData.GetAlphamaps

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public function GetAlphamaps(x: int, y: int, width: int, height: int): float[,,];
public float[,,] GetAlphamaps(int x, int y, int width, int height);

Parameters

Description

Returns the alpha map at a position x, y given a width and height.

The returned array is three-dimensional - the first two dimensions represent x and y coordinates on the map, while the third denotes the splatmap texture to which the alphamap is applied.

#pragma strict
// Add some random "noise" to the alphamaps.
function AddAlphaNoise(t: Terrain, noiseScale: float) {
	var maps: var = t.terrainData.GetAlphamaps(0, 0, t.terrainData.alphamapWidth, t.terrainData.alphamapHeight);
	for (var y: var = 0; y < t.terrainData.alphamapHeight; y++) {
		for (var x: var = 0; x < t.terrainData.alphamapWidth; x++) {
			var a0: var = maps[x, y, 0];
			var a1: var = maps[x, y, 1];
			a0 += Random.value * noiseScale;
			a1 += Random.value * noiseScale;
			var total: var = a0 + a1;
			maps[x, y, 0] = a0 / total;
			maps[x, y, 1] = a1 / total;
		}
	}
	t.terrainData.SetAlphamaps(0, 0, maps);
}
using UnityEngine;
using System.Collections;

public class ExampleClass : MonoBehaviour { // Add some random "noise" to the alphamaps. void AddAlphaNoise(Terrain t, float noiseScale) { var maps = t.terrainData.GetAlphamaps(0, 0, t.terrainData.alphamapWidth, t.terrainData.alphamapHeight);

for (var y = 0; y < t.terrainData.alphamapHeight; y++) { for (var x = 0; x < t.terrainData.alphamapWidth; x++) { var a0 = maps[x, y, 0]; var a1 = maps[x, y, 1]; a0 += Random.value * noiseScale; a1 += Random.value * noiseScale; var total = a0 + a1; maps[x, y, 0] = a0 / total; maps[x, y, 1] = a1 / total; } } t.terrainData.SetAlphamaps(0, 0, maps); } }