Unity里获取Material里所有的Texture

背景：通过Material获取Texture的接口有：Material.mainTexture, Material.GetTexture(string propertyName); 但没有一个接口可以直接获取Material的所有textures.

解决方法一：

利用资源依赖，EditorUtility. CollectDependencies()。

static string [] GetMaterialTexturePaths( Material _mat )
    {
        List<string > results = new List <string>();
        Object[] roots = new Object[] { _mat };
        Object[] dependObjs = EditorUtility. CollectDependencies(roots );
        foreach (Object dependObj in dependObjs )
        {
            if (dependObj .GetType() == typeof(Texture2D ))
            {
                string texpath = AssetDatabase.GetAssetPath (dependObj. GetInstanceID());
                results.Add (texpath);
            }
        }
        return results .ToArray();
    }

解决方法二：

利用序列化，得到Shader的Property,从而得到Shader里Texture相关的PropertyName。 Unity4.1版本以上，ShaderUtil已经提供相应接口。

static string[] GetCertainMaterialTexturePaths(Material _mat)
    {
        List<string > results = new List<string >();

        Shader shader = _mat.shader;
        for (int i = 0; i < ShaderUtil.GetPropertyCount(shader); ++i)
        {
            if (ShaderUtil .GetPropertyType(shader, i) == ShaderUtil.ShaderPropertyType .TexEnv)
            {
                string propertyName = ShaderUtil .GetPropertyName(shader, i);
                Texture tex = _mat.GetTexture(propertyName);
                string texPath = AssetDatabase .GetAssetPath(tex.GetInstanceID());
                results.Add(texPath);
            }
        }

        return results.ToArray();
    }

对于ShaderUtil不提供对外接口的低版本，还有方法，参考http://answers.unity3d.com/questions/179255/a-way-to-iterateenumerate-shader-properties.html

using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using UnityEditor;
using UnityEngine;
using System.IO;
using System.Collections;

public static class ShaderUtilInterface
{
    public static Dictionary<string, MethodInfo> methods = new Dictionary<string, MethodInfo>();

    static ShaderUtilInterface()
    {
        var asm = AppDomain.CurrentDomain.GetAssemblies().FirstOrDefault(a=>a.GetTypes().Any(t=>t.Name == "ShaderUtil"));
        if(asm != null)
        {
            var tp = asm.GetTypes().FirstOrDefault(t=>t.Name == "ShaderUtil");
            foreach(var method in tp.GetMethods(BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Static))
            {
                methods[method.Name] = method;
            }
        }
    }

    public static List<Texture> GetTextures(this Material shader)
    {
        var list = new List<Texture>();
        var count = shader.GetPropertyCount();
        for(var i = 0; i < count; i++)
        {
            if(shader.GetPropertyType(i)==4)
            {
                list.Add((Texture)shader.GetProperty(i));
            }
        }
        return list;
    }

    public static int GetPropertyCount(this Material shader)
    {
        return Call<int>("GetPropertyCount", shader.shader);
    }

    public static int GetPropertyType(this Material shader, int index)
    {
        return Call<int>("GetPropertyType", shader.shader, index);
    }

    public static string GetPropertyName(this Material shader, int index)
    {
        return Call<string>("GetPropertyName", shader.shader, index);
    }

    public static void SetProperty(this Material material, int index, object value)
    {
        var name = material.GetPropertyName(index);
        var type = material.GetPropertyType(index);
        switch(type)
        {
        case 0:
            material.SetColor(name, (Color)value);
            break;
        case 1:
            material.SetVector(name, (Vector4) value);
            break;
        case 2:
            material.SetFloat(name, (float)value);
            break;
        case 3:
            material.SetFloat(name, (float)value);
            break;
        case 4:
            material.SetTexture(name, (Texture) value);
            break;
        }
    }

    public static object GetProperty(this Material material, int index)
    {
        var name = material.GetPropertyName(index);
        var type = material.GetPropertyType(index);
        switch(type)
        {
        case 0:
            return material.GetColor(name);

        case 1:
            return material.GetVector(name);

        case 2:
        case 3:
            return material.GetFloat(name);

        case 4:
            return material.GetTexture(name);

        }
    return null;
    }

    public static T Call<T>(string name, params object[] parameters)
    {
        return (T)methods[name].Invoke(null, parameters);
    }

}