【操作界面】
将下面的代码直接复制粘贴后，可以在下图中找到打开操作界面的位置。注意要在unity当中将颜色空间改为线性空间。
在下方的操作界面中，可以拖进来对应的纹理，可以在Preview Output中预览当前的合成结果，点击下面的按钮会生成Mask Map贴图。
实现和注释看下文的代码。
【代码原理】
using System.Collections;
using System.Collections.Generic;
using System.IO;
using UnityEditor;
using UnityEngine;
public class MaskMapEditor : EditorWindow//扩展编辑器要继承EditorWindow
{
private Texture2D metallic, occlusion, detailmask, smoothness;//四个纹理字段
private Texture2D _metallic, _occlusion, _detailmask, _smoothness;//这四个字段用于预览的实现
private Material mat;//带有Shader的材质
private bool changed;
[MenuItem("HDRP/CreateMaskMap")]
static void OpenMaskMapEditor()//实现点击菜单栏的按钮弹出窗口
{
MaskMapEditor maskMapEditor = GetWindow<MaskMapEditor>(false, "MaskMap Editor");//创建窗口
maskMapEditor.titleContent.text = "MaskMap Editor";//给窗口命名
maskMapEditor.Init();//初始化
}
private void Init()
{
if (mat == null)
{
mat = new Material(Shader.Find("Hidden/MaskMap"));//根据MaskMap这个Shader创建材质
mat.hideFlags = HideFlags.HideAndDontSave;//材质不保存
}
}
public void OnGUI()
{
GetInput();
Preview();
CreateMask();
}
private void CreateMask()
{
if (GUILayout.Button("Create Mask Map"))
{
GenPicture();
}
}
private void GenPicture()
{
Texture2D output = GetTexture();
string savePath = EditorUtility.SaveFilePanel("Save", Application.dataPath, "texture.png", "png");
File.WriteAllBytes(savePath,output.EncodeToPNG());//将纹理保存为png格式，也可以是jpg、exr等格式
AssetDatabase.Refresh();//更新，要不然在Unity当中不会看到生成的图片（在win的文件管理器中可以看到）
}
private Texture2D GetTexture()
{
if (metallic != null)
{
mat.SetTexture("_Metallic", metallic);//给Shader的属性赋值
}
if (occlusion != null)
{
mat.SetTexture("_Occlusion", occlusion);
}
if (detailmask != null)
{
mat.SetTexture("_DetailMask", detailmask);
}
if (smoothness != null)
{
mat.SetTexture("_Smoothness", smoothness);
}
RenderTexture tempRT = new RenderTexture(2048, 2048, 32, RenderTextureFormat.ARGB32);//生成纹理，分辨率可以自己改为1024的，也可以自己在编辑器上做出多个可供选择的分辨率，容易实现
tempRT.Create();
Texture2D temp2 = new Texture2D(tempRT.width, tempRT.height, TextureFormat.ARGB32, false);
Graphics.Blit(temp2, tempRT, mat);//将temp2纹理的值通过mat赋值到tempRT，核心的代码，可以好好看看对这个方法的解释
RenderTexture prev = RenderTexture.active;
RenderTexture.active = tempRT;//设置当前active的纹理
Texture2D output = new Texture2D(tempRT.width, tempRT.height, TextureFormat.ARGB32, false);//创建一个RGBA格式的纹理
output.ReadPixels(new Rect(0, 0, tempRT.width, tempRT.height), 0, 0);//读取当前active的纹理
output.Apply();//apply将改变写入
RenderTexture.active = prev;
return output;
}
private void GetInput()
{
EditorGUILayout.BeginHorizontal("Box");
GUILayout.Label("Input Textures");
EditorGUILayout.EndHorizontal();
EditorGUILayout.BeginHorizontal("Box");
_metallic = TextureField("metallic", metallic);
if (_metallic != metallic)
{
metallic = _metallic;
changed = true;
}
_occlusion = TextureField("occlusion", occlusion);
if (_occlusion != occlusion)
{
occlusion = _occlusion;
changed = true;
}
_detailmask = TextureField("detailmask", detailmask);
if (_detailmask != detailmask)
{
detailmask = _detailmask;
changed = true;
}
_smoothness = TextureField("smoothness", smoothness);
if (_smoothness != smoothness)
{
smoothness = _smoothness;
changed = true;
}
EditorGUILayout.EndHorizontal();
}
private Texture2D preview = null;
private void Preview()
{
EditorGUILayout.BeginHorizontal("Box");
GUILayout.Label("Preview Output");
EditorGUILayout.EndHorizontal();
EditorGUILayout.BeginHorizontal("Box");
Rect previewRect = new Rect(this.position.width / 2-75, 250, 150, 150);
if (preview == null)
{
preview = Texture2D.blackTexture;
}
if (changed)
{
preview = GetTexture();
changed = false;
}
EditorGUI.DrawPreviewTexture(previewRect, preview);
EditorGUILayout.Space(160);
EditorGUILayout.EndHorizontal();
}
private Texture2D TextureField(string name,Texture2D texture)
{
EditorGUILayout.BeginVertical();
var style = new GUIStyle(GUI.skin.label);
style.alignment = TextAnchor.MiddleCenter;
style.fixedWidth = 150;
GUILayout.Label(name,style);
Texture2D result = EditorGUILayout.ObjectField(texture,typeof(Texture2D),false,GUILayout.Width(150),GUILayout.Height(150)) as Texture2D;
EditorGUILayout.EndHorizontal();
return result;
}
}Shader "Hidden/MaskMap"
{
Properties
{
_MainTex("Texture",2D) = "white"{}
_Metallic("Texture", 2D) = "black"{}
_Occlusion("Texture", 2D) = "black"{}
_DetailMask("Texture",2D) = "black"{}
_Smoothness("Texture",2D) = "black"{}
}
SubShader
{
Tags { "RenderType" = "Transparent" }
LOD 100
Pass
{
CGPROGRAM
#pragma vertex vert
#pragma fragment frag
#include "UnityCG.cginc"
struct appdata
{
float4 vertex : POSITION;
float2 uv : TEXCOORD0;
};
struct v2f
{
float2 uv : TEXCOORD0;
float4 vertex : SV_POSITION;
};
sampler2D _MainTex;
float4 _MainTex_ST;
sampler2D _Metallic;
sampler2D _Occlusion;
sampler2D _DetailMask;
sampler2D _Smoothness;
v2f vert (appdata v)
{
v2f o;
o.vertex = UnityObjectToClipPos(v.vertex);
o.uv = v.uv;
return o;
}
fixed4 frag (v2f i) : SV_Target
{
// sample the texture
fixed4 col = tex2D(_MainTex, i.uv);
col.r = tex2D(_Metallic, i.uv).r;
col.g = tex2D(_Occlusion, i.uv).g;
col.b = tex2D(_DetailMask, i.uv).b;
col.a = tex2D(_Smoothness, i.uv).g;
col.a = pow(col.a, 0.45); //线性空间会对a通道做gamma校正，要自己校正
return col;
}
ENDCG
}
}
}
