7.8 KiB
7.8 KiB
BrightnessSaturationAndContrast
给摄像机添加脚本
添加2个Meta，让其可以在编辑器模式下运行，并且只能绑定Camera组件。
[ExecuteInEditMode]
[RequireComponent(typeof(Camera))]
实现基础类
using UnityEngine;
[ExecuteInEditMode]
[RequireComponent(typeof(Camera))]
public class PostEffectsBase : MonoBehaviour
{
protected void CheckResources()
{
bool isSupported = CheckSupport();
if (isSupported == false)
{
NotSupported();
}
}
protected bool CheckSupport()
{
if (SystemInfo.supportsImageEffects == false || SystemInfo.supportsRenderTextures == false)
{
Debug.LogWarning("Not Supported!");
return false;
}
return true;
}
protected void NotSupported()
{
enabled = false;
}
protected Material CheckShaderAndCreateMaterial(Shader shader, Material material)
{
if (shader == null)
return null;
if (shader.isSupported && material && material.shader == shader)
return material;
if (!shader.isSupported)
return null;
else
{
material = new Material(shader);
material.hideFlags = HideFlags.DontSave;
if (material)
return material;
else
return null;
}
}
protected void Start()
{
CheckResources();
}
}
之后根据需求在子类中添加变量：
using UnityEngine;
public class BrightnessSaturationAndContrast : PostEffectsBase
{
[Range(0.0f, 3.0f)]
public float brightness = 1.0f;
[Range(0.0f, 3.0f)]
public float saturation = 1.0f;
[Range(0.0f, 3.0f)]
public float contrast = 1.0f;
public Shader briSatConShader;
private Material briSatConMaterial;
public Material material
{
get
{
briSatConMaterial = CheckShaderAndCreateMaterial(briSatConShader, briSatConMaterial);
return briSatConMaterial;
}
}
private void OnRenderImage(RenderTexture src, RenderTexture dest)
{
if (material != null)
{
material.SetFloat("_Brightness", brightness);
material.SetFloat("_Saturation", saturation);
material.SetFloat("_Contrast", contrast);
Graphics.Blit(src, dest, material);
}
else
{
Graphics.Blit(src, dest);
}
}
}
最后在OnRenderImage中调用Graphics.Blit()进行渲染。
添加后处理Shader
Shader "PostProcess/BrightnessSaturationAndContrast" {
Properties {
_MainTex ("Base", 2D) = "white" {}
_Brightness("Brightness",Float)=1
_Saturation("Saturation",Float)=1
_Contrast("Constrast",Float)=1
}
SubShader {
Pass{
ZTest Always Cull Off ZWrite Off
CGPROGRAM
#pragma vertex vert
#pragma fragment frag
#include "UnityCG.cginc"
sampler2D _MainTex;
half _Brightness;
half _Saturation;
half _Contrast;
struct v2f{
float4 pos : SV_POSITION;
half2 uv : TEXCOORD0;
};
v2f vert(appdata_img v)
{
v2f o;
o.pos = UnityObjectToClipPos(v.vertex);
o.uv=v.texcoord;
return o;
}
fixed4 frag(v2f i) : SV_Target{
fixed4 renderTex=tex2D(_MainTex,i.uv);
fixed3 finalColor=renderTex.rgb * _Brightness;
fixed luminance=0.2125*renderTex.r+0.7154*renderTex.g+0.0721*renderTex.b;
fixed3 luminanceColor=fixed3(luminance,luminance,luminance);
finalColor =lerp(luminanceColor,finalColor,_Saturation);
fixed3 avgColor=fixed3(0.5,0.5,0.5);
finalColor=lerp(avgColor,finalColor,_Contrast);
return fixed4(finalColor,renderTex.a);
}
ENDCG
}
}
Fallback Off
}
高斯模糊
与之前不同，这里利用RenderTexture.GetTemporary函数分配了一块与屏幕图像大小相同的缓冲区。这是因为，高斯模糊需要调用两个Pass，我们需要使用一块中间缓存来存储第一个Pass执行完毕后得到的模糊结果。RenderTexture buffer = RenderTexture.GetTemporary(rtW, rtH, 0);我们首先调用Graphics.Blit(src, buffer, material, 0),使用Shader中的第一个pass对src进行处理，并将结果存储在了buffer中。然后在调用Graphics.Blit(src, buffer, material, 1),使用Shader中的第二个Pass对buffer进行处理，返回最终的屏幕图像。最后，我们还需要调用RenderTexture.ReleaseTemporary来释放之前分配的缓存。
private void OnRenderImage(RenderTexture src, RenderTexture dest)
{
if (material != null)
{
int rtW = src.width;
int rtH = src.height;
RenderTexture buffer = RenderTexture.GetTemporary(rtW, rtH, 0);
Graphics.Blit(src, buffer, material, 0);
Graphics.Blit(buffer, dest, material, 1);
RenderTexture.Release(buffer);
}
else
{
Graphics.Blit(src, dest);
}
}
实现降采样：
private void OnRenderImage(RenderTexture src, RenderTexture dest)
{
if (material != null)
{
int rtW = src.width / downSample;
int rtH = src.height / downSample;
RenderTexture buffer = RenderTexture.GetTemporary(rtW, rtH, 0);
buffer.filterMode=FilterMode.Bilinear;
Graphics.Blit(src, buffer, material, 0);
Graphics.Blit(buffer, dest, material, 1);
RenderTexture.Release(buffer);
}
else
{
Graphics.Blit(src, dest);
}
}
CGINCLUDE
使用CGINCLUDE与ENDCG关键字将通用部分引用给其他Pass
Shader "Unity Shaders Book/Chapter 12/Gaussian Blur" {
Properties {
_MainTex ("Base (RGB)", 2D) = "white" {}
_BlurSize ("Blur Size", Float) = 1.0
}
SubShader {
CGINCLUDE
#include "UnityCG.cginc"
sampler2D _MainTex;
half4 _MainTex_TexelSize;
float _BlurSize;
struct v2f {
float4 pos : SV_POSITION;
half2 uv[5]: TEXCOORD0;
};
v2f vertBlurVertical(appdata_img v) {
v2f o;
o.pos = mul(UNITY_MATRIX_MVP, v.vertex);
half2 uv = v.texcoord;
o.uv[0] = uv;
o.uv[1] = uv + float2(0.0, _MainTex_TexelSize.y * 1.0) * _BlurSize;
o.uv[2] = uv - float2(0.0, _MainTex_TexelSize.y * 1.0) * _BlurSize;
o.uv[3] = uv + float2(0.0, _MainTex_TexelSize.y * 2.0) * _BlurSize;
o.uv[4] = uv - float2(0.0, _MainTex_TexelSize.y * 2.0) * _BlurSize;
return o;
}
v2f vertBlurHorizontal(appdata_img v) {
v2f o;
o.pos = mul(UNITY_MATRIX_MVP, v.vertex);
half2 uv = v.texcoord;
o.uv[0] = uv;
o.uv[1] = uv + float2(_MainTex_TexelSize.x * 1.0, 0.0) * _BlurSize;
o.uv[2] = uv - float2(_MainTex_TexelSize.x * 1.0, 0.0) * _BlurSize;
o.uv[3] = uv + float2(_MainTex_TexelSize.x * 2.0, 0.0) * _BlurSize;
o.uv[4] = uv - float2(_MainTex_TexelSize.x * 2.0, 0.0) * _BlurSize;
return o;
}
fixed4 fragBlur(v2f i) : SV_Target {
float weight[3] = {0.4026, 0.2442, 0.0545};
fixed3 sum = tex2D(_MainTex, i.uv[0]).rgb * weight[0];
for (int it = 1; it < 3; it++) {
sum += tex2D(_MainTex, i.uv[it*2-1]).rgb * weight[it];
sum += tex2D(_MainTex, i.uv[it*2]).rgb * weight[it];
}
return fixed4(sum, 1.0);
}
ENDCG
ZTest Always Cull Off ZWrite Off
Pass {
NAME "GAUSSIAN_BLUR_VERTICAL"
CGPROGRAM
#pragma vertex vertBlurVertical
#pragma fragment fragBlur
ENDCG
}
Pass {
NAME "GAUSSIAN_BLUR_HORIZONTAL"
CGPROGRAM
#pragma vertex vertBlurHorizontal
#pragma fragment fragBlur
ENDCG
}
}
FallBack "Diffuse"
}