车展素材利用

镜面反光效果

把shader和MirrorrRerflectionScript脚本剥离出来，可以直接在新建的plane地面上加上shader和脚本（下附），把Texture Size调为1024--2048之间，效果就比较明显了，我们在地面上新建一个cube物体，靠近地面就可以看到反光效果了。

下面是镜面效果的脚本

using UnityEngine;
using System.Collections;

// This is in fact just the Water script from Pro Standard Assets,
// just with refraction stuff removed.

[ExecuteInEditMode] // Make mirror live-update even when not in play mode
public class MirrorReflectionScript : MonoBehaviour
{
public bool m_DisablePixelLights = true;
public int m_TextureSize = 256;
public float m_ClipPlaneOffset = 0.07f;

public LayerMask m_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()
{
    var rend = GetComponent<Renderer>();
    if (!enabled || !rend || !rend.sharedMaterial || !rend.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( m_DisablePixelLights )
        QualitySettings.pixelLightCount = 0;
    
    UpdateCameraModes( cam, reflectionCamera );
    
    // Render reflection
    // Reflect camera around reflection plane
    float d = -Vector3.Dot (normal, pos) - m_ClipPlaneOffset;
    Vector4 reflectionPlane = new Vector4 (normal.x, normal.y, normal.z, d);
    
    Matrix4x4 reflection = Matrix4x4.zero;
    CalculateReflectionMatrix (ref reflection, 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 = CameraSpacePlane( reflectionCamera, pos, normal, 1.0f );
    //Matrix4x4 projection = cam.projectionMatrix;
    Matrix4x4 projection = cam.CalculateObliqueMatrix(clipPlane);
    reflectionCamera.projectionMatrix = projection;
    
    reflectionCamera.cullingMask = ~(1<<4) & m_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 = rend.sharedMaterials;
    foreach( Material mat in materials ) {
        if( mat.HasProperty("_ReflectionTex") )
            mat.SetTexture( "_ReflectionTex", m_ReflectionTexture );
    }
    
    // Restore pixel light count
    if( m_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();
}


private void UpdateCameraModes( Camera src, Camera dest )
{
    if( dest == null )
        return;
    // set camera to clear the same way as current camera
    dest.clearFlags = src.clearFlags;
    dest.backgroundColor = src.backgroundColor;        
    if( src.clearFlags == CameraClearFlags.Skybox )
    {
        Skybox sky = src.GetComponent(typeof(Skybox)) as Skybox;
        Skybox mysky = dest.GetComponent(typeof(Skybox)) as Skybox;
        if( !sky || !sky.material )
        {
            mysky.enabled = false;
        }
        else
        {
            mysky.enabled = true;
            mysky.material = sky.material;
        }
    }
    // update other values to match current camera.
    // even if we are supplying custom camera&projection matrices,
    // some of values are used elsewhere (e.g. skybox uses far plane)
    dest.farClipPlane = src.farClipPlane;
    dest.nearClipPlane = src.nearClipPlane;
    dest.orthographic = src.orthographic;
    dest.fieldOfView = src.fieldOfView;
    dest.aspect = src.aspect;
    dest.orthographicSize = src.orthographicSize;
}

// 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 != m_TextureSize )
    {
        if( m_ReflectionTexture )
            DestroyImmediate( m_ReflectionTexture );
        m_ReflectionTexture = new RenderTexture( m_TextureSize, m_TextureSize, 16 );
        m_ReflectionTexture.name = "__MirrorReflection" + GetInstanceID();
        m_ReflectionTexture.isPowerOfTwo = true;
        m_ReflectionTexture.hideFlags = HideFlags.DontSave;
        m_OldReflectionTextureSize = m_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.GetComponent<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;
    }        
}

// Extended sign: returns -1, 0 or 1 based on sign of a
private static float sgn(float a)
{
    if (a > 0.0f) return 1.0f;
    if (a < 0.0f) return -1.0f;
    return 0.0f;
}

// Given position/normal of the plane, calculates plane in camera space.
private Vector4 CameraSpacePlane (Camera cam, Vector3 pos, Vector3 normal, float sideSign)
{
    Vector3 offsetPos = pos + normal * m_ClipPlaneOffset;
    Matrix4x4 m = cam.worldToCameraMatrix;
    Vector3 cpos = m.MultiplyPoint( offsetPos );
    Vector3 cnormal = m.MultiplyVector( normal ).normalized * sideSign;
    return new Vector4( cnormal.x, cnormal.y, cnormal.z, -Vector3.Dot(cpos,cnormal) );
}

// Calculates reflection matrix around the given plane
private static void CalculateReflectionMatrix (ref Matrix4x4 reflectionMat, Vector4 plane)
{
    reflectionMat.m00 = (1F - 2F*plane[0]*plane[0]);
    reflectionMat.m01 = (   - 2F*plane[0]*plane[1]);
    reflectionMat.m02 = (   - 2F*plane[0]*plane[2]);
    reflectionMat.m03 = (   - 2F*plane[3]*plane[0]);
    
    reflectionMat.m10 = (   - 2F*plane[1]*plane[0]);
    reflectionMat.m11 = (1F - 2F*plane[1]*plane[1]);
    reflectionMat.m12 = (   - 2F*plane[1]*plane[2]);
    reflectionMat.m13 = (   - 2F*plane[3]*plane[1]);
    
    reflectionMat.m20 = (   - 2F*plane[2]*plane[0]);
    reflectionMat.m21 = (   - 2F*plane[2]*plane[1]);
    reflectionMat.m22 = (1F - 2F*plane[2]*plane[2]);
    reflectionMat.m23 = (   - 2F*plane[3]*plane[2]);
    
    reflectionMat.m30 = 0F;
    reflectionMat.m31 = 0F;
    reflectionMat.m32 = 0F;
    reflectionMat.m33 = 1F;
}
}

摄像机跟随和旋转

只需要把CameraRotate脚本挂在物体上，运行之后便可以看到一该物体为视角的旋转动画，我们可以在x speed和y speed中调节摄像机旋转的速度值。

下面是摄像机旋转的脚本

using UnityEngine;
using System.Collections;

public class CameraRotate : MonoBehaviour
{
public Transform targetObject;
public Vector3 targetOffset;
public float averageDistance = 5.0f;
public float maxDistance = 20;
public float minDistance = .6f;
public float xSpeed = 200.0f;
public float ySpeed = 200.0f;
public int yMinLimit = -80;
public int yMaxLimit = 80;
public int zoomSpeed = 40;
public float panSpeed = 0.3f;
public float zoomDampening = 5.0f;
public float rotateOnOff = 1;

private float xDeg = 0.0f;
private float yDeg = 0.0f;
private float currentDistance;
private float desiredDistance;
private Quaternion currentRotation;
private Quaternion desiredRotation;
private Quaternion rotation;
private Vector3 position;
private float idleTimer = 0.0f;
private float idleSmooth = 0.0f;

void Start() { Init(); }
void OnEnable() { Init(); }

public void Init()
{
    if (!targetObject)
    {
        GameObject go = new GameObject("Cam Target");
        go.transform.position = transform.position + (transform.forward * averageDistance);
        targetObject = go.transform;
    }

    currentDistance = averageDistance;
    desiredDistance = averageDistance;
    
    position = transform.position;
    rotation = transform.rotation;
    currentRotation = transform.rotation;
    desiredRotation = transform.rotation;
   
    xDeg = Vector3.Angle(Vector3.right, transform.right );
    yDeg = Vector3.Angle(Vector3.up, transform.up );
    position = targetObject.position - (rotation * Vector3.forward * currentDistance + targetOffset);
}

void LateUpdate()
{  
    if (Input.GetMouseButton(2) && Input.GetKey(KeyCode.LeftAlt) && Input.GetKey(KeyCode.LeftControl))
    {
        desiredDistance -= Input.GetAxis("Mouse Y") * 0.02f  * zoomSpeed*0.125f * Mathf.Abs(desiredDistance);
    }
    else if (Input.GetMouseButton(0) )
    {
        xDeg += Input.GetAxis("Mouse X") * xSpeed * 0.02f;
        yDeg -= Input.GetAxis("Mouse Y") * ySpeed * 0.02f;
        yDeg = ClampAngle(yDeg, yMinLimit, yMaxLimit);
        
        desiredRotation = Quaternion.Euler(yDeg, xDeg, 0);
        currentRotation = transform.rotation;
        rotation = Quaternion.Lerp(currentRotation, desiredRotation, 0.02f  * zoomDampening);
        transform.rotation = rotation;
        idleTimer=0;
        idleSmooth=0;
   
    }else{
        idleTimer+=0.02f ;
        if(idleTimer > rotateOnOff && rotateOnOff > 0){
            idleSmooth+=(0.02f +idleSmooth)*0.005f;
            idleSmooth = Mathf.Clamp(idleSmooth, 0, 1);
            xDeg += xSpeed * 0.001f * idleSmooth;
        }

        yDeg = ClampAngle(yDeg, yMinLimit, yMaxLimit);
        desiredRotation = Quaternion.Euler(yDeg, xDeg, 0);
        currentRotation = transform.rotation;
        rotation = Quaternion.Lerp(currentRotation, desiredRotation, 0.02f  * zoomDampening*2);
        transform.rotation = rotation;
    }

    desiredDistance -= Input.GetAxis("Mouse ScrollWheel") * 0.02f  * zoomSpeed * Mathf.Abs(desiredDistance);
    desiredDistance = Mathf.Clamp(desiredDistance, minDistance, maxDistance);
    currentDistance = Mathf.Lerp(currentDistance, desiredDistance, 0.02f  * zoomDampening);
    position = targetObject.position - (rotation * Vector3.forward * currentDistance + targetOffset);
    transform.position = position;
}

private static float ClampAngle(float angle, float min, float max)
{
    if (angle < -360)
        angle += 360;
    if (angle > 360)
        angle -= 360;
    return Mathf.Clamp(angle, min, max);
}
}