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Unity Engine

GetAlphamaps(int, int, int, int)

Returns the alpha map at a position x, y given a width and height.
Read time 1 minuteLast updated 6 days ago

Definition

  • Type: Method
  • Namespace: UnityEngine
  • Assembly: UnityEngine.TerrainModule
public float[,,] GetAlphamaps(int x, int y, int width, int height)

Parameters

x

int
The x offset to read from.

y

int
The y offset to read from.

width

int
The width of the alpha map area to read.

height

int
The height of the alpha map area to read.

Returns

Type

Description

float[,,]A 3D array of floats, where the 3rd dimension represents the mixing weight of each splatmap at each x,y coordinate.

Remarks

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

Examples

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