动态改变StandardShader的RenderingMode让模型透明

如何用脚本动态的改变Unity5中标准材质的渲染模式，让模型透明？

先上代码：

SetMaterialRenderingMode.cs

using UnityEngine;using System.Collections;//设置材质的渲染模式public class SetMaterialRenderingMode : MonoBehaviour {    public Material mat;void Start () {        setMaterialRenderingMode(mat, RenderingMode.Fade);}    public enum RenderingMode{        Opaque,        Cutout,        Fade,        Transparent    }    //设置材质的渲染模式    private void setMaterialRenderingMode(Material material, RenderingMode renderingMode){        switch (renderingMode){            case RenderingMode.Opaque:                material.SetInt("_SrcBlend", (int)UnityEngine.Rendering.BlendMode.One);                material.SetInt("_DstBlend", (int)UnityEngine.Rendering.BlendMode.Zero);                material.SetInt("_ZWrite", 1);                material.DisableKeyword("_ALPHATEST_ON");                material.DisableKeyword("_ALPHABLEND_ON");                material.DisableKeyword("_ALPHAPREMULTIPLY_ON");                material.renderQueue = -1;                break;            case RenderingMode.Cutout:                material.SetInt("_SrcBlend", (int)UnityEngine.Rendering.BlendMode.One);                material.SetInt("_DstBlend", (int)UnityEngine.Rendering.BlendMode.Zero);                material.SetInt("_ZWrite", 1);                material.EnableKeyword("_ALPHATEST_ON");                material.DisableKeyword("_ALPHABLEND_ON");                material.DisableKeyword("_ALPHAPREMULTIPLY_ON");                material.renderQueue = 2450;                break;            case RenderingMode.Fade:                material.SetInt("_SrcBlend", (int)UnityEngine.Rendering.BlendMode.SrcAlpha);                material.SetInt("_DstBlend", (int)UnityEngine.Rendering.BlendMode.OneMinusSrcAlpha);                material.SetInt("_ZWrite", 0);                material.DisableKeyword("_ALPHATEST_ON");                material.EnableKeyword("_ALPHABLEND_ON");                material.DisableKeyword("_ALPHAPREMULTIPLY_ON");                material.renderQueue = 3000;                break;            case RenderingMode.Transparent:                material.SetInt("_SrcBlend", (int)UnityEngine.Rendering.BlendMode.One);                material.SetInt("_DstBlend", (int)UnityEngine.Rendering.BlendMode.OneMinusSrcAlpha);                material.SetInt("_ZWrite", 0);                material.DisableKeyword("_ALPHATEST_ON");                material.DisableKeyword("_ALPHABLEND_ON");                material.EnableKeyword("_ALPHAPREMULTIPLY_ON");                material.renderQueue = 3000;                break;        }    }}

最近在做项目的时候遇到了一个需要动态切换模型透明、不透明效果的功能。unity4.x的时候是切换材质的shader，但是现在unity5的标准材质已经可以切换渲染模式了，那么肯定有方法在不更换shader的前提下直接切换材质的透明、不透明效果。自己花了不少时间，尝试设置Material和Shader的属性，发现都没有实现效果，很是挠头啊，肯定是有哪些地方没有弄明白导致失败，因为在编辑模式下，Inspector面板中标准材质已经提供了一个切换渲染模式的功能按钮，Rendering Mode，可以实现透明和不透明之间的切换，而且有4种模式。那么答案肯定就在这个UI的源代码里。在网上查了不少资料，发现标准材质的UI脚本叫做StandardShaderGUI.cs，又经过一番搜索终于在一个外国论坛帖子的回复中找到了外国同行分享的标准材质GUI的源代码，这个源代码已经被外国友人改过了，所以有些地方可能和官方源代码有些出入，不过大部分应该相同，先上代码：

CustomStandardShaderGUI.cs

using System;using UnityEngine; namespace UnityEditor{    internal class CustomStandardShaderGUI : ShaderGUI{    private enum WorkflowMode    {        Specular,        Metallic,        Dielectric    }     public enum BlendMode    {        Opaque,        Cutout,        Fade,        // Old school alpha-blending mode, fresnel does not affect amount of transparency        Transparent // Physically plausible transparency mode, implemented as alpha pre-multiply    }     private static class Styles    {        public static GUIStyle optionsButton = "PaneOptions";        public static GUIContent uvSetLabel = new GUIContent("UV Set");        public static GUIContent[] uvSetOptions = new GUIContent[] { new GUIContent("UV channel 0"), new GUIContent("UV channel 1") };         public static string emptyTootip = "";        public static GUIContent albedoText = new GUIContent("Albedo", "Albedo (RGB) and Transparency (A)");        public static GUIContent alphaCutoffText = new GUIContent("Alpha Cutoff", "Threshold for alpha cutoff");        public static GUIContent specularMapText = new GUIContent("Specular", "Specular (RGB) and Smoothness (A)");        public static GUIContent metallicMapText = new GUIContent("Metallic", "Metallic (R) and Smoothness (A)");        public static GUIContent smoothnessText = new GUIContent("Smoothness", "");        public static GUIContent normalMapText = new GUIContent("Normal Map", "Normal Map");        public static GUIContent heightMapText = new GUIContent("Height Map", "Height Map (G)");        public static GUIContent occlusionText = new GUIContent("Occlusion", "Occlusion (G)");        public static GUIContent emissionText = new GUIContent("Emission", "Emission (RGB)");        public static GUIContent detailMaskText = new GUIContent("Detail Mask", "Mask for Secondary Maps (A)");        public static GUIContent detailAlbedoText = new GUIContent("Detail Albedo x2", "Albedo (RGB) multiplied by 2");        public static GUIContent detailNormalMapText = new GUIContent("Normal Map", "Normal Map");         public static string whiteSpaceString = " ";        public static string primaryMapsText = "Main Maps";        public static string secondaryMapsText = "Secondary Maps";        public static string renderingMode = "Rendering Mode";        public static GUIContent emissiveWarning = new GUIContent ("Emissive value is animated but the material has not been configured to support emissive. Please make sure the material itself has some amount of emissive.");        public static GUIContent emissiveColorWarning = new GUIContent ("Ensure emissive color is non-black for emission to have effect.");        public static readonly string[] blendNames = Enum.GetNames (typeof (BlendMode));    }     MaterialProperty blendMode = null;    MaterialProperty albedoMap = null;    MaterialProperty albedoColor = null;    MaterialProperty alphaCutoff = null;    MaterialProperty specularMap = null;    MaterialProperty specularColor = null;    MaterialProperty metallicMap = null;    MaterialProperty metallic = null;    MaterialProperty smoothness = null;    MaterialProperty bumpScale = null;    MaterialProperty bumpMap = null;    MaterialProperty occlusionStrength = null;    MaterialProperty occlusionMap = null;    MaterialProperty heigtMapScale = null;    MaterialProperty heightMap = null;    MaterialProperty emissionScaleUI = null;    MaterialProperty emissionColorUI = null;    MaterialProperty emissionColorForRendering = null;    MaterialProperty emissionMap = null;    MaterialProperty detailMask = null;    MaterialProperty detailAlbedoMap = null;    MaterialProperty detailNormalMapScale = null;    MaterialProperty detailNormalMap = null;    MaterialProperty uvSetSecondary = null;     MaterialEditor m_MaterialEditor;    WorkflowMode m_WorkflowMode = WorkflowMode.Specular;     bool m_FirstTimeApply = true;     public void FindProperties (MaterialProperty[] props)    {        blendMode = FindProperty ("_Mode", props);        albedoMap = FindProperty ("_MainTex", props);        albedoColor = FindProperty ("_Color", props);        alphaCutoff = FindProperty ("_Cutoff", props);        specularMap = FindProperty ("_SpecGlossMap", props, false);        specularColor = FindProperty ("_SpecColor", props, false);        metallicMap = FindProperty ("_MetallicGlossMap", props, false);        metallic = FindProperty ("_Metallic", props, false);        if (specularMap != null && specularColor != null)            m_WorkflowMode = WorkflowMode.Specular;        else if (metallicMap != null && metallic != null)            m_WorkflowMode = WorkflowMode.Metallic;        else            m_WorkflowMode = WorkflowMode.Dielectric;        smoothness = FindProperty ("_Glossiness", props);        bumpScale = FindProperty ("_BumpScale", props);        bumpMap = FindProperty ("_BumpMap", props);        heigtMapScale = FindProperty ("_Parallax", props);        heightMap = FindProperty("_ParallaxMap", props);        occlusionStrength = FindProperty ("_OcclusionStrength", props);        occlusionMap = FindProperty ("_OcclusionMap", props);        emissionScaleUI = FindProperty ("_EmissionScaleUI", props);        emissionColorUI = FindProperty ("_EmissionColorUI", props);        emissionColorForRendering = FindProperty ("_EmissionColor", props);        emissionMap = FindProperty ("_EmissionMap", props);        detailMask = FindProperty ("_DetailMask", props);        detailAlbedoMap = FindProperty ("_DetailAlbedoMap", props);        detailNormalMapScale = FindProperty ("_DetailNormalMapScale", props);        detailNormalMap = FindProperty ("_DetailNormalMap", props);        uvSetSecondary = FindProperty ("_UVSec", props);    }     public override void OnGUI (MaterialEditor materialEditor, MaterialProperty[] props)    {        FindProperties (props); // MaterialProperties can be animated so we do not cache them but fetch them every event to ensure animated values are updated correctly        m_MaterialEditor = materialEditor;        Material material = materialEditor.target as Material;         ShaderPropertiesGUI (material);         // Make sure that needed keywords are set up if we're switching some existing        // material to a standard shader.        if (m_FirstTimeApply)        {            SetMaterialKeywords (material, m_WorkflowMode);            m_FirstTimeApply = false;        }    }     public void ShaderPropertiesGUI (Material material)    {        // Use default labelWidth        EditorGUIUtility.labelWidth = 0f;         // Detect any changes to the material        EditorGUI.BeginChangeCheck();        {            BlendModePopup();             // Primary properties            GUILayout.Label (Styles.primaryMapsText, EditorStyles.boldLabel);            DoAlbedoArea(material);            DoSpecularMetallicArea();            m_MaterialEditor.TexturePropertySingleLine(Styles.normalMapText, bumpMap, bumpMap.textureValue != null ? bumpScale : null);            m_MaterialEditor.TexturePropertySingleLine(Styles.heightMapText, heightMap, heightMap.textureValue != null ? heigtMapScale : null);            m_MaterialEditor.TexturePropertySingleLine(Styles.occlusionText, occlusionMap, occlusionMap.textureValue != null ? occlusionStrength : null);            DoEmissionArea(material);            m_MaterialEditor.TexturePropertySingleLine(Styles.detailMaskText, detailMask);            EditorGUI.BeginChangeCheck();            m_MaterialEditor.TextureScaleOffsetProperty(albedoMap);            if (EditorGUI.EndChangeCheck())                emissionMap.textureScaleAndOffset = albedoMap.textureScaleAndOffset; // Apply the main texture scale and offset to the emission texture as well, for Enlighten's sake             EditorGUILayout.Space();             // Secondary properties            GUILayout.Label(Styles.secondaryMapsText, EditorStyles.boldLabel);            m_MaterialEditor.TexturePropertySingleLine(Styles.detailAlbedoText, detailAlbedoMap);            m_MaterialEditor.TexturePropertySingleLine(Styles.detailNormalMapText, detailNormalMap, detailNormalMapScale);            m_MaterialEditor.TextureScaleOffsetProperty(detailAlbedoMap);            m_MaterialEditor.ShaderProperty(uvSetSecondary, Styles.uvSetLabel.text);             EditorGUILayout.Space();         }        if (EditorGUI.EndChangeCheck())        {            foreach (var obj in blendMode.targets)                MaterialChanged((Material)obj, m_WorkflowMode);        }    }     internal void DetermineWorkflow(MaterialProperty[] props)    {        if (FindProperty("_SpecGlossMap", props, false) != null && FindProperty("_SpecColor", props, false) != null)            m_WorkflowMode = WorkflowMode.Specular;        else if (FindProperty("_MetallicGlossMap", props, false) != null && FindProperty("_Metallic", props, false) != null)            m_WorkflowMode = WorkflowMode.Metallic;        else            m_WorkflowMode = WorkflowMode.Dielectric;    }     public override void AssignNewShaderToMaterial (Material material, Shader oldShader, Shader newShader)    {        base.AssignNewShaderToMaterial(material, oldShader, newShader);         if (oldShader == null || !oldShader.name.Contains("Legacy Shaders/"))            return;         BlendMode blendMode = BlendMode.Opaque;        if (oldShader.name.Contains("/Transparent/Cutout/"))        {            blendMode = BlendMode.Cutout;        }        else if (oldShader.name.Contains("/Transparent/"))        {            // NOTE: legacy shaders did not provide physically based transparency            // therefore Fade mode            blendMode = BlendMode.Fade;        }        material.SetFloat("_Mode", (float)blendMode);         //DetermineWorkflow( ShaderUtil.GetMaterialProperties(new Material[] { material }) );        MaterialChanged(material, m_WorkflowMode);    }     void BlendModePopup()    {        EditorGUI.showMixedValue = http://blog.csdn.net/zhangyukof/article/details/blendMode.hasMixedValue;        var mode = (BlendMode)blendMode.floatValue;        EditorGUI.BeginChangeCheck();        mode = (BlendMode)EditorGUILayout.Popup(Styles.renderingMode, (int)mode, Styles.blendNames);        if (EditorGUI.EndChangeCheck())        {            m_MaterialEditor.RegisterPropertyChangeUndo("Rendering Mode");            blendMode.floatValue = http://blog.csdn.net/zhangyukof/article/details/(float)mode;        }         EditorGUI.showMixedValue = false;    }     void DoAlbedoArea(Material material)    {        m_MaterialEditor.TexturePropertySingleLine(Styles.albedoText, albedoMap, albedoColor);        if (((BlendMode)material.GetFloat("_Mode") == BlendMode.Cutout))        {            m_MaterialEditor.ShaderProperty(alphaCutoff, Styles.alphaCutoffText.text, MaterialEditor.kMiniTextureFieldLabelIndentLevel+1);        }    }     void DoEmissionArea(Material material)    {        bool showEmissionColorAndGIControls = emissionScaleUI.floatValue > 0f;        bool hadEmissionTexture = emissionMap.textureValue != null;         // Do controls        m_MaterialEditor.TexturePropertySingleLine(Styles.emissionText, emissionMap, showEmissionColorAndGIControls ? emissionColorUI : null, emissionScaleUI);         // Set default emissionScaleUI if texture was assigned        if (emissionMap.textureValue != null && !hadEmissionTexture && emissionScaleUI.floatValue <= 0f)            emissionScaleUI.floatValue = http://blog.csdn.net/zhangyukof/article/details/1.0f;         // Dynamic Lightmapping mode        if (showEmissionColorAndGIControls)        {            bool shouldEmissionBeEnabled = ShouldEmissionBeEnabled(EvalFinalEmissionColor(material));            EditorGUI.BeginDisabledGroup(!shouldEmissionBeEnabled);             m_MaterialEditor.LightmapEmissionProperty (MaterialEditor.kMiniTextureFieldLabelIndentLevel + 1);             EditorGUI.EndDisabledGroup();        }         if (!HasValidEmissiveKeyword(material))        {            EditorGUILayout.HelpBox(Styles.emissiveWarning.text, MessageType.Warning);        }     }     void DoSpecularMetallicArea()    {        if (m_WorkflowMode == WorkflowMode.Specular)        {            if (specularMap.textureValue == null)                m_MaterialEditor.TexturePropertyTwoLines(Styles.specularMapText, specularMap, specularColor, Styles.smoothnessText, smoothness);            else                m_MaterialEditor.TexturePropertySingleLine(Styles.specularMapText, specularMap);         }        else if (m_WorkflowMode == WorkflowMode.Metallic)        {            if (metallicMap.textureValue == null)                m_MaterialEditor.TexturePropertyTwoLines(Styles.metallicMapText, metallicMap, metallic, Styles.smoothnessText, smoothness);            else                m_MaterialEditor.TexturePropertySingleLine(Styles.metallicMapText, metallicMap);        }    }     public static void SetupMaterialWithBlendMode(Material material, BlendMode blendMode)    {        switch (blendMode)        {            case BlendMode.Opaque:                material.SetInt("_SrcBlend", (int)UnityEngine.Rendering.BlendMode.One);                material.SetInt("_DstBlend", (int)UnityEngine.Rendering.BlendMode.Zero);                material.SetInt("_ZWrite", 1);                material.DisableKeyword("_ALPHATEST_ON");                material.DisableKeyword("_ALPHABLEND_ON");                material.DisableKeyword("_ALPHAPREMULTIPLY_ON");                material.renderQueue = -1;                break;            case BlendMode.Cutout:                material.SetInt("_SrcBlend", (int)UnityEngine.Rendering.BlendMode.One);                material.SetInt("_DstBlend", (int)UnityEngine.Rendering.BlendMode.Zero);                material.SetInt("_ZWrite", 1);                material.EnableKeyword("_ALPHATEST_ON");                material.DisableKeyword("_ALPHABLEND_ON");                material.DisableKeyword("_ALPHAPREMULTIPLY_ON");                material.renderQueue = 2450;                break;            case BlendMode.Fade:                material.SetInt("_SrcBlend", (int)UnityEngine.Rendering.BlendMode.SrcAlpha);                material.SetInt("_DstBlend", (int)UnityEngine.Rendering.BlendMode.OneMinusSrcAlpha);                material.SetInt("_ZWrite", 0);                material.DisableKeyword("_ALPHATEST_ON");                material.EnableKeyword("_ALPHABLEND_ON");                material.DisableKeyword("_ALPHAPREMULTIPLY_ON");                material.renderQueue = 3000;                break;            case BlendMode.Transparent:                material.SetInt("_SrcBlend", (int)UnityEngine.Rendering.BlendMode.One);                material.SetInt("_DstBlend", (int)UnityEngine.Rendering.BlendMode.OneMinusSrcAlpha);                material.SetInt("_ZWrite", 0);                material.DisableKeyword("_ALPHATEST_ON");                material.DisableKeyword("_ALPHABLEND_ON");                material.EnableKeyword("_ALPHAPREMULTIPLY_ON");                material.renderQueue = 3000;                break;        }    }     // Calculate final HDR _EmissionColor (gamma space) from _EmissionColorUI (LDR, gamma) & _EmissionScaleUI (gamma)    static Color EvalFinalEmissionColor(Material material)    {        return material.GetColor("_EmissionColorUI") * material.GetFloat("_EmissionScaleUI");    }     static bool ShouldEmissionBeEnabled (Color color)    {        return color.grayscale > (0.1f / 255.0f);    }     static void SetMaterialKeywords(Material material, WorkflowMode workflowMode)    {        // Note: keywords must be based on Material value not on MaterialProperty due to multi-edit & material animation        // (MaterialProperty value might come from renderer material property block)        SetKeyword (material, "_NORMALMAP", material.GetTexture ("_BumpMap") || material.GetTexture ("_DetailNormalMap"));        if (workflowMode == WorkflowMode.Specular)            SetKeyword (material, "_SPECGLOSSMAP", material.GetTexture ("_SpecGlossMap"));        else if (workflowMode == WorkflowMode.Metallic)            SetKeyword (material, "_METALLICGLOSSMAP", material.GetTexture ("_MetallicGlossMap"));        SetKeyword (material, "_PARALLAXMAP", material.GetTexture ("_ParallaxMap"));        SetKeyword (material, "_DETAIL_MULX2", material.GetTexture ("_DetailAlbedoMap") || material.GetTexture ("_DetailNormalMap"));         bool shouldEmissionBeEnabled = ShouldEmissionBeEnabled (material.GetColor("_EmissionColor"));        SetKeyword (material, "_EMISSION", shouldEmissionBeEnabled);         // Setup lightmap emissive flags        MaterialGlobalIlluminationFlags flags = material.globalIlluminationFlags;        if ((flags & (MaterialGlobalIlluminationFlags.BakedEmissive | MaterialGlobalIlluminationFlags.RealtimeEmissive)) != 0)        {            flags &= ~MaterialGlobalIlluminationFlags.EmissiveIsBlack;            if (!shouldEmissionBeEnabled)                flags |= MaterialGlobalIlluminationFlags.EmissiveIsBlack;             material.globalIlluminationFlags = flags;        }    }     bool HasValidEmissiveKeyword (Material material)    {        // Material animation might be out of sync with the material keyword.        // So if the emission support is disabled on the material, but the property blocks have a value that requires it, then we need to show a warning.        // (note: (Renderer MaterialPropertyBlock applies its values to emissionColorForRendering))        bool hasEmissionKeyword = material.IsKeywordEnabled ("_EMISSION");        if (!hasEmissionKeyword && ShouldEmissionBeEnabled (emissionColorForRendering.colorValue))            return false;        else            return true;    }     static void MaterialChanged(Material material, WorkflowMode workflowMode)    {        // Clamp EmissionScale to always positive        if (material.GetFloat("_EmissionScaleUI") < 0.0f)            material.SetFloat("_EmissionScaleUI", 0.0f);         // Apply combined emission value        Color emissionColorOut = EvalFinalEmissionColor (material);        material.SetColor("_EmissionColor", emissionColorOut);         // Handle Blending modes        SetupMaterialWithBlendMode(material, (BlendMode)material.GetFloat("_Mode"));         SetMaterialKeywords(material, workflowMode);    }     static void SetKeyword(Material m, string keyword, bool state)    {        if (state)            m.EnableKeyword (keyword);        else            m.DisableKeyword (keyword);    }} } // namespace UnityEditor

搜索了一下RenderingMode的相关能容，在代码的283行找到了SetupMaterialWithBlendMode方法，这个方法中的内容就是我们切换渲染模式用到的代码了，整理后代码就是文章最上方的setMaterialRenderingMode方法了，有两个参数，第一个是材质，二个是渲染模式。

OK，问题解决。