Unity3d 镜面反射 vertex and frag Shader源代码

Unity3d 镜面反射

网上能找到的基本上是固定管道或表面渲染的shader。

特此翻译为顶点、片段渲染的Shader，

本源代码仅仅涉及shader与cs部分。

Editor部分使用NGUI绘制的，

请自行下载NGUI

unity3d 版本号:v4.3.1

ReflectionMirror.cs

using UnityEngine;
using System.Collections;
using System;

/// <summary>
/// 反射效果
/// </summary>
[AddComponentMenu("GameCore/SpecialEffect/Reflection Mirror")]
[ExecuteInEditMode]
public class ReflectionMirror : MonoBehaviour
{
    public bool DisablePixelLights = true;
    public int TextureSize = 512;
    public float ClipPlaneOffset = 0;
    public LayerMask ReflectLayers = -1;

    private Hashtable m_ReflectionCameras = new Hashtable(); // Camera -> Camera table
    private RenderTexture m_ReflectionTexture = null;
    private int m_OldReflectionTextureSize = 0;

    private static bool s_InsideRendering = false;

    // This is called when it's known that the object will be rendered by some
    // camera. We render reflections and do other updates here.
    // Because the script executes in edit mode, reflections for the scene view
    // camera will just work!
    public void OnWillRenderObject()
    {
        if (!enabled || !renderer || !renderer.sharedMaterial || !renderer.enabled)
            return;

        Camera cam = Camera.current;
        if (!cam)
            return;

        // Safeguard from recursive reflections.
        if (s_InsideRendering)
            return;
        s_InsideRendering = true;

        Camera reflectionCamera;
        CreateMirrorObjects(cam, out reflectionCamera);

        // find out the reflection plane: position and normal in world space
        Vector3 pos = transform.position;
        Vector3 normal = transform.up;
        // Optionally disable pixel lights for reflection
        int oldPixelLightCount = QualitySettings.pixelLightCount;
        if (DisablePixelLights)
            QualitySettings.pixelLightCount = 0;

        CoreTool.CloneCameraModes(cam, reflectionCamera);

        // Render reflection
        // Reflect camera around reflection plane
        float d = -Vector3.Dot(normal, pos) - ClipPlaneOffset;
        Vector4 reflectionPlane = new Vector4(normal.x, normal.y, normal.z, d);

        Matrix4x4 reflection = CoreTool.CalculateReflectionMatrix(Matrix4x4.zero, reflectionPlane);

        Vector3 oldpos = cam.transform.position;
        Vector3 newpos = reflection.MultiplyPoint(oldpos);
        reflectionCamera.worldToCameraMatrix = cam.worldToCameraMatrix * reflection;

        // Setup oblique projection matrix so that near plane is our reflection
        // plane. This way we clip everything below/above it for free.
        Vector4 clipPlane = CoreTool.CameraSpacePlane(reflectionCamera, pos, normal, 1.0f, ClipPlaneOffset);

        Matrix4x4 projection = cam.projectionMatrix;

        projection = CoreTool.CalculateObliqueMatrix(projection, clipPlane);

        reflectionCamera.projectionMatrix = projection;

        reflectionCamera.cullingMask = ~(1 << 4) & ReflectLayers.value; // never render water layer
        reflectionCamera.targetTexture = m_ReflectionTexture;

        GL.SetRevertBackfacing(true);
        reflectionCamera.transform.position = newpos;
        Vector3 euler = cam.transform.eulerAngles;
        reflectionCamera.transform.eulerAngles = new Vector3(0, euler.y, euler.z);
        reflectionCamera.Render();
        reflectionCamera.transform.position = oldpos;
        GL.SetRevertBackfacing(false);
        Material[] materials = renderer.sharedMaterials;
        foreach (Material mat in materials)
        {
            if (mat.HasProperty("_ReflectionTex"))
                mat.SetTexture("_ReflectionTex", m_ReflectionTexture);
        }

        // Set matrix on the shader that transforms UVs from object space into screen
        // space. We want to just project reflection texture on screen.
        Matrix4x4 scaleOffset = Matrix4x4.TRS(
            new Vector3(0.5f, 0.5f, 0.5f), Quaternion.identity, new Vector3(0.5f, 0.5f, 0.5f));
        Vector3 scale = transform.lossyScale;
        Matrix4x4 mtx = transform.localToWorldMatrix * Matrix4x4.Scale(new Vector3(1.0f / scale.x, 1.0f / scale.y, 1.0f / scale.z));
        mtx = scaleOffset * cam.projectionMatrix * cam.worldToCameraMatrix * mtx;
        foreach (Material mat in materials)
        {
            mat.SetMatrix("_ProjMatrix", mtx);
        }
        // Restore pixel light count
        if (DisablePixelLights)
            QualitySettings.pixelLightCount = oldPixelLightCount;
        s_InsideRendering = false;
    }

    // Cleanup all the objects we possibly have created
    void OnDisable()
    {
        if (m_ReflectionTexture)
        {
            DestroyImmediate(m_ReflectionTexture);
            m_ReflectionTexture = null;
        }
        foreach (DictionaryEntry kvp in m_ReflectionCameras)
            DestroyImmediate(((Camera)kvp.Value).gameObject);
        m_ReflectionCameras.Clear();
    }

    // On-demand create any objects we need
    private void CreateMirrorObjects(Camera currentCamera, out Camera reflectionCamera)
    {
        reflectionCamera = null;

        // Reflection render texture
        if (!m_ReflectionTexture || m_OldReflectionTextureSize != TextureSize)
        {
            if (m_ReflectionTexture)
                DestroyImmediate(m_ReflectionTexture);
            m_ReflectionTexture = new RenderTexture(TextureSize, TextureSize,0);
            m_ReflectionTexture.name = "__MirrorReflection" + GetInstanceID();
            m_ReflectionTexture.isPowerOfTwo = true;
            m_ReflectionTexture.hideFlags = HideFlags.DontSave;
            m_ReflectionTexture.antiAliasing = 4;
            m_ReflectionTexture.anisoLevel = 0;
            m_OldReflectionTextureSize = TextureSize;
        }

        // Camera for reflection
        reflectionCamera = m_ReflectionCameras[currentCamera] as Camera;
        if (!reflectionCamera) // catch both not-in-dictionary and in-dictionary-but-deleted-GO
        {
            GameObject go = new GameObject("Mirror Refl Camera id" + GetInstanceID() + " for " + currentCamera.GetInstanceID(), typeof(Camera), typeof(Skybox));
            reflectionCamera = go.camera;
            reflectionCamera.enabled = false;
            reflectionCamera.transform.position = transform.position;
            reflectionCamera.transform.rotation = transform.rotation;
            reflectionCamera.gameObject.AddComponent("FlareLayer");
            go.hideFlags = HideFlags.HideAndDontSave;
            m_ReflectionCameras[currentCamera] = reflectionCamera;
        }
    }
}

ReflectionMirrorEditor.cs

using System.Collections;
using System;
using UnityEditor;
using UnityEngine;
/// <summary>
/// 反射效果
/// </summary>
[CustomEditor(typeof(ReflectionMirror))]
public class ReflectionMirrorEditor : Editor
{
    string[] _renderTextureOptions = new string[8] { "16", "32", "64", "128", "256", "512", "1024", "2048" };
    int _renderTextureWidthDefaultIndex = 5;
    int _renderTextureWidthIndex = 5;
    SerializedProperty _sp;
    public override void OnInspectorGUI()
    {
        EditorGUILayout.HelpBox("This the reflection effect,it has mirror or sphere reflection!",MessageType.Info);
        if (NGUIEditorTools.DrawHeader("Reflection Settings"))
        {
            NGUIEditorTools.BeginContents();
            {
                NGUIEditorTools.DrawProperty("Disable PixelLights", this.serializedObject, "DisablePixelLights");
                NGUIEditorTools.DrawProperty("Reflect Layers", this.serializedObject, "ReflectLayers");
                NGUIEditorTools.DrawProperty("ClipPlane Offset", this.serializedObject, "ClipPlaneOffset");
            }
            NGUIEditorTools.EndContents();
        }
        if (NGUIEditorTools.DrawHeader("Render Texture Settings"))
        {
            NGUIEditorTools.BeginContents();
            {
                _sp = this.serializedObject.FindProperty("TextureSize");
                _renderTextureWidthIndex = GetTextureOptionsIndex(_sp.intValue.ToString());
                EditorGUILayout.BeginHorizontal();
                EditorGUILayout.LabelField("TexSize:", GUILayout.Width(100));
                _renderTextureWidthIndex = EditorGUILayout.Popup(_renderTextureWidthIndex, _renderTextureOptions);
                EditorGUILayout.EndHorizontal();

                if (GUILayout.Button("Make Default Value"))
                {
                    _renderTextureWidthIndex = _renderTextureWidthDefaultIndex;
                }
                _sp.intValue = int.Parse(_renderTextureOptions[_renderTextureWidthIndex]);
            }
            NGUIEditorTools.EndContents();
        }

        this.serializedObject.ApplyModifiedProperties();
    }

    int GetTextureOptionsIndex(string value)
    {
        int index = 0;
        for (int i = 0; i < _renderTextureOptions.Length; i++)
        {
            if (_renderTextureOptions[i].Equals(value, StringComparison.OrdinalIgnoreCase))
            {
                index = i;
            }
        }
        return index;
    }
}

Shader

Shader "GameCore/SpecialEffect/Reflection Mirror"
{
    Properties {
        _ReflectionTex ("Reflection", 2D) = "white" {TexGen ObjectLinear }
		_ReflectionColor("Color",Color) = (1,1,1,1)
	}
	//PC
	SubShader {
        Tags {
            "RenderType"="Opaque"}
		LOD 100
		Pass {
            CGPROGRAM
			#pragma vertex vert
			#pragma fragment frag
			#include "UnityCG.cginc"

			uniform float4x4 _ProjMatrix;
            uniform sampler2D _ReflectionTex;
            float4 _ReflectionColor;
            struct outvertex {
                float4 pos : SV_POSITION;
                float3 uv : TEXCOORD0;
            };
            outvertex vert(appdata_tan v) {
                outvertex o;
                o.pos = mul (UNITY_MATRIX_MVP,v.vertex);
                float3 viewDir = ObjSpaceViewDir(v.vertex);
				o.uv = mul(_ProjMatrix,float4(viewDir,0));
				return o;
            }

			float4 frag(outvertex i) : COLOR {
                half4 reflcol = tex2Dproj(_ReflectionTex,i.uv);
                return reflcol*_ReflectionColor;
            }
			ENDCG
		}
	}
	//Mobile
	SubShader {
        Tags {
            "RenderType"="Opaque"}
		LOD 100
		Pass {
            CGPROGRAM
			#pragma vertex vert
			#pragma fragment frag
			#include "UnityCG.cginc"

			uniform float4x4 _ProjMatrix;
            uniform sampler2D _ReflectionTex;
            float4 _ReflectionColor;
            struct outvertex {
                float4 pos : SV_POSITION;
                float3 uv : TEXCOORD0;
                float4 posProj;
            };
            outvertex vert(appdata_tan v) {
                outvertex o;
                o.pos = mul (UNITY_MATRIX_MVP,v.vertex);
                o.posProj = mul(_ProjMatrix, v.vertex);
				return o;
            }
			float4 frag(outvertex i) : COLOR {
				half4 reflcol = tex2D(_ReflectionTex,float2(i.posProj) / i.posProj.w);
                return reflcol*_ReflectionColor;
            }
			ENDCG
		}
	}
}

来源链接: http://pan.baidu.com/s/1gdyzyNL