做出这种古老效果,需要: 颜色发黄, 晕影效果, 灰尘与刮痕的效果。
建立一个c#脚本,将要放在摄像头中
先声明变量
oldFilmShader 所需shader(一会需要编写)
OldFilmEffectAmount 古老的程度(最后做插值的程度值)
sepiaColor 屏幕的颜色(调至黑黄)
vigentteTexture 老电影式基本贴图
vigentteAmount 所占比重
scratchesTexture 刮痕贴图
scratchesYspeed 刮痕y方向移动速度
scratchesXspeed 刮痕x方向移动速度
Texture2D dustTexture; 灰尘贴图
dustYSpeed 灰尘y方向移动速度
dustXSpeed 灰尘x方向移动速度
randomValue 随机值
public Shader oldFilmShader; public float OldFilmEffectAmount = 1.0f; public Color sepiaColor = Color.white; public Texture2D vigentteTexture; public float vigentteAmount = 1.0f; public Texture2D scratchesTexture; public float scratchesYspeed = 10.0f; public float scratchesXspeed = 10.0f; public Texture2D dustTexture; public float dustYSpeed = 10.0f; public float dustXSpeed = 10.0f; private Material curMaterial; private float randomValue;
依旧需要 OnRenderImage()这个函数抓取摄像机的图像
把所需变量传入shader
最后拷贝源纹理到目的渲染纹理
Graphics.Blit()
void OnRenderImage(RenderTexture sourceTex, RenderTexture destTex) { if (oldFilmShader != null) { material.SetColor("_SepiaColor", sepiaColor); material.SetFloat("_VigentteAmount", vigentteAmount); material.SetFloat("_OldFilmEffectAmount", OldFilmEffectAmount); if (vigentteTexture) { material.SetTexture("_VigentteTex", vigentteTexture); } if (scratchesTexture) { material.SetTexture("_ScratchesTex", scratchesTexture); material.SetFloat("_ScratchesYSpeed", scratchesYspeed); material.SetFloat("_ScratchesXSpeed", scratchesXspeed); } if (dustTexture) { material.SetTexture("_DustTex", dustTexture); material.SetFloat("_DustXSpeed", dustXSpeed); material.SetFloat("_DustYSpeed", dustYSpeed); material.SetFloat("_RandomValue", randomValue); } Graphics.Blit(sourceTex, destTex, material); } else { Graphics.Blit(sourceTex, destTex); } }
再看shader
声明变量
distortion 扭曲程度
cubicDistortion 三维扭曲程度
Properties { _MainTex ("Base(RGB)", 2D) = "white" {} _VignetteTex ("VignetteTexture", 2D) = "white"{} _ScratchesTex ("ScartchesTexture", 2D) = "white"{} _DustTex ("DustTexture", 2D) = "white"{} _SepiaColor ("SepiaColor", Color) = (1,1,1,1) _EffectAmount ("OldFilmEffectAmount", Range(0,1)) = 1.0 _VignetteAmount ("Vignette Opacity", Range(0,1)) = 1.0 _ScratchesYSpeed ("ScratchesYSpeed", Float) = 10.0 _ScratchesXSpeed ("ScratchesXSpeed", Float) = 10.0 _dustXSpeed ("DustXSpeed", Float) = 10.0 _dustYSpeed ("DustYSpeed", Float) = 10.0 _RandomValue ("RandomValue", Float) = 1.0 _Contrast ("Contrast", Float) = 3.0 _distortion ("Distortion", Float) = 0.2 _cubicDistortion ("CubicDistortion", Float) = 0.6 _scale ("Scale(Zoom)", Float) = 0.8 }
镜头桶形失真校正算法,产生桶形畸变效果
将矩形物体拍摄成四边向外凸形成桶形的影像,就称镜头具有负畸变,或桶形畸变
一会需要用此对uv进行变换
传入uv值float2 coord
传出扭曲的uv值
float2 barrelDistortion(float2 coord) { // Inspired by SynthEyes lens distortion algorithm // See http://www.ssontech.com/content/lensalg.htm float2 h = coord.xy - float2(0.5, 0.5); float r2 = h.x * h.x + h.y * h.y; float f = 1.0 + r2 * (_distortion + _cubicDistortion * sqrt(r2)); return f * _scale * h + 0.5; }
从v2f_img i中获取图像的颜色和uv值
通过上面的barrelDistortion()函数获得扭曲的uv
刮痕的uv
对刮痕的uv进行变换,使之随时间移动
lum 求图像的饱和度
最终颜色初定义 = 饱和度+所定义颜色(浮动的明暗度(线性插值))
求颜色的对比度次方
不同的层合在一起构成屏幕最终特效
先与老电影式基本贴图做插值混合
然后与刮痕混合,与白色的插值来制造刮痕的闪烁效果
与灰尘相乘混合,与白色的插值来制造灰尘的闪烁效果
最后与图像的本来面貌做插值
得到最终颜色
fixed4 frag(v2f_img i) : COLOR { //Get the colors from the RenderTexture and the uv's //from the v2f_img struct half2 distortedUV = barrelDistortion(i.uv); distortedUV = half2(i.uv.x, i.uv.y + (_RandomValue * _SinTime.z * 0.005)); fixed4 renderTex = tex2D(_MainTex, i.uv); //Get the pixels from the Vignette Texture fixed4 vignetteTex = tex2D(_VignetteTex, i.uv); //Process the Scratches UV and pixels half2 scratchesUV = half2(i.uv.x + (_RandomValue * _SinTime.z * _ScratchesXSpeed), i.uv.y + (_Time.x * _ScratchesYSpeed)); fixed4 scratchesTex = tex2D(_ScratchesTex, scratchesUV); //Process the Dust UV and pixels half2 dustUV = half2(i.uv.x + (_RandomValue * (_SinTime.z * _dustXSpeed)), i.uv.y + (_RandomValue * (_SinTime.z * _dustYSpeed))); fixed4 dustTex = tex2D(_DustTex, dustUV); // get the luminosity values from the render texture using the YIQ values. fixed lum = dot (fixed3(0.299, 0.587, 0.114), renderTex.rgb); //Add the constant color to the lum values fixed4 finalColor = lum + lerp(_SepiaColor, _SepiaColor + fixed4(0.1f,0.1f,0.1f,1.0f), _RandomValue); finalColor = pow(finalColor, _Contrast); //Create a constant white color we can use to adjust opacity of effects fixed3 constantWhite = fixed3(1,1,1); //Composite together the different layers to create finsl Screen Effect finalColor = lerp(finalColor, finalColor * vignetteTex, _VignetteAmount); finalColor.rgb *= lerp(scratchesTex, constantWhite, (_RandomValue)); finalColor.rgb *= lerp(dustTex.rgb, constantWhite, (_RandomValue * _SinTime.z)); finalColor = lerp(renderTex, finalColor, _EffectAmount); return finalColor; }
代码如下
using UnityEngine; using System.Collections; public class ShaderTest : MonoBehaviour { #region Variables public Shader oldFilmShader; public float OldFilmEffectAmount = 1.0f; public Color sepiaColor = Color.white; public Texture2D vigentteTexture; public float vigentteAmount = 1.0f; public Texture2D scratchesTexture; public float scratchesYspeed = 10.0f; public float scratchesXspeed = 10.0f; public Texture2D dustTexture; public float dustYSpeed = 10.0f; public float dustXSpeed = 10.0f; private Material curMaterial; private float randomValue; #endregion #region Properties public Material material { get { if (curMaterial == null) { curMaterial = new Material(oldFilmShader); curMaterial.hideFlags = HideFlags.HideAndDontSave; } return curMaterial; } } #endregion void OnRenderImage(RenderTexture sourceTex, RenderTexture destTex) { if (oldFilmShader != null) { material.SetColor("_SepiaColor", sepiaColor); material.SetFloat("_VigentteAmount", vigentteAmount); material.SetFloat("_OldFilmEffectAmount", OldFilmEffectAmount); if (vigentteTexture) { material.SetTexture("_VigentteTex", vigentteTexture); } if (scratchesTexture) { material.SetTexture("_ScratchesTex", scratchesTexture); material.SetFloat("_ScratchesYSpeed", scratchesYspeed); material.SetFloat("_ScratchesXSpeed", scratchesXspeed); } if (dustTexture) { material.SetTexture("_DustTex", dustTexture); material.SetFloat("_DustXSpeed", dustXSpeed); material.SetFloat("_DustYSpeed", dustYSpeed); material.SetFloat("_RandomValue", randomValue); } Graphics.Blit(sourceTex, destTex, material); } else { Graphics.Blit(sourceTex, destTex); } } // Use this for initialization void Start() { if (SystemInfo.supportsImageEffects == false) { enabled = false; return; } if (oldFilmShader != null && oldFilmShader.isSupported == false) { enabled = false; } } // Update is called once per frame void Update() { vigentteAmount = Mathf.Clamp01(vigentteAmount); OldFilmEffectAmount = Mathf.Clamp(OldFilmEffectAmount, 0f, 1.5f); randomValue = Random.Range(-1f, 1f); } }
shader:
Shader "Custom/TestShader" { Properties { _MainTex ("Base(RGB)", 2D) = "white" {} _VignetteTex ("VignetteTexture", 2D) = "white"{} _ScratchesTex ("ScartchesTexture", 2D) = "white"{} _DustTex ("DustTexture", 2D) = "white"{} _SepiaColor ("SepiaColor", Color) = (1,1,1,1) _EffectAmount ("OldFilmEffectAmount", Range(0,1)) = 1.0 _VignetteAmount ("Vignette Opacity", Range(0,1)) = 1.0 _ScratchesYSpeed ("ScratchesYSpeed", Float) = 10.0 _ScratchesXSpeed ("ScratchesXSpeed", Float) = 10.0 _dustXSpeed ("DustXSpeed", Float) = 10.0 _dustYSpeed ("DustYSpeed", Float) = 10.0 _RandomValue ("RandomValue", Float) = 1.0 _Contrast ("Contrast", Float) = 3.0 _distortion ("Distortion", Float) = 0.2 _cubicDistortion ("CubicDistortion", Float) = 0.6 _scale ("Scale(Zoom)", Float) = 0.8 } SubShader { Pass { CGPROGRAM #pragma vertex vert_img #pragma fragment frag #pragma fragmentoption ARB_precision_hint_fastest #include "UnityCG.cginc" uniform sampler2D _MainTex; uniform sampler2D _VignetteTex; uniform sampler2D _ScratchesTex; uniform sampler2D _DustTex; fixed4 _SepiaColor; fixed _VignetteAmount; fixed _ScratchesYSpeed; fixed _ScratchesXSpeed; fixed _dustXSpeed; fixed _dustYSpeed; fixed _EffectAmount; fixed _RandomValue; fixed _Contrast; float _distortion; float _cubicDistortion; float _scale; float2 barrelDistortion(float2 coord) { // Inspired by SynthEyes lens distortion algorithm // See http://www.ssontech.com/content/lensalg.htm float2 h = coord.xy - float2(0.5, 0.5); float r2 = h.x * h.x + h.y * h.y; float f = 1.0 + r2 * (_distortion + _cubicDistortion * sqrt(r2)); return f * _scale * h + 0.5; } fixed4 frag(v2f_img i) : COLOR { //Get the colors from the RenderTexture and the uv's //from the v2f_img struct half2 distortedUV = barrelDistortion(i.uv); distortedUV = half2(i.uv.x, i.uv.y + (_RandomValue * _SinTime.z * 0.005)); fixed4 renderTex = tex2D(_MainTex, i.uv); //Get the pixels from the Vignette Texture fixed4 vignetteTex = tex2D(_VignetteTex, i.uv); //Process the Scratches UV and pixels half2 scratchesUV = half2(i.uv.x + (_RandomValue * _SinTime.z * _ScratchesXSpeed), i.uv.y + (_Time.x * _ScratchesYSpeed)); fixed4 scratchesTex = tex2D(_ScratchesTex, scratchesUV); //Process the Dust UV and pixels half2 dustUV = half2(i.uv.x + (_RandomValue * (_SinTime.z * _dustXSpeed)), i.uv.y + (_RandomValue * (_SinTime.z * _dustYSpeed))); fixed4 dustTex = tex2D(_DustTex, dustUV); // get the luminosity values from the render texture using the YIQ values. fixed lum = dot (fixed3(0.299, 0.587, 0.114), renderTex.rgb); //Add the constant color to the lum values fixed4 finalColor = lum + lerp(_SepiaColor, _SepiaColor + fixed4(0.1f,0.1f,0.1f,1.0f), _RandomValue); finalColor = pow(finalColor, _Contrast); //Create a constant white color we can use to adjust opacity of effects fixed3 constantWhite = fixed3(1,1,1); //Composite together the different layers to create finsl Screen Effect finalColor = lerp(finalColor, finalColor * vignetteTex, _VignetteAmount); finalColor.rgb *= lerp(scratchesTex, constantWhite, (_RandomValue)); finalColor.rgb *= lerp(dustTex.rgb, constantWhite, (_RandomValue * _SinTime.z)); finalColor = lerp(renderTex, finalColor, _EffectAmount); return finalColor; } ENDCG } } FallBack off }
图片资源:
vigentteTexture
scratchesTexture
<span style="font-size:14px;color:#FF6600;">dustTexture</span>
--------by wolf96