2024年水波涟漪的意思

原地址：【Unity教程】可实时交互的涟漪效果_哔哩哔哩 (゜-゜)つロ干杯~-bilibili

思路的简单实现

点击物体的UV,传入shader，获得一张，根据点生生成的小圆球

将图片传入扩散shader，神奇的公式

 float3 offset = float3(_SourceTex_TexelSize.xy,0); float col12 = tex2D(_SourceTex,i.uv + offset.zy ).x; float col10 = tex2D(_SourceTex,i.uv - offset.zy ).x; float col01 = tex2D(_SourceTex,i.uv - offset.xz ).x; float col21 = tex2D(_SourceTex,i.uv + offset.xz ).x; float col11 = tex2D(_PrevTex,i.uv).x; float finel = (col10 + col12 + col01 + col21)*0.5 - col11; finel = finel*0.99; return float4(finel,0,0,1);

将生成的高度场贴图传入

根据高度场生成法线贴图

C#代码

using System.Collections; using System.Collections.Generic; using UnityEngine; public class MeshUVRipple : MonoBehaviour { public Camera camera; public float radius; private Shader _generateRippleHight; private RenderTexture _tempTexture; private RenderTexture _currentTexture; private RenderTexture _prevTexture; private Material _hightRipple; private Material _point_material; private Material material; private void Awake() { if (null == camera) { camera = Camera.main; } _currentTexture = CreatRT(); _tempTexture = CreatRT(); _prevTexture = CreatRT(); _point_material = new Material(Shader.Find("Custom/GenerateRippleHight")); _hightRipple = new Material(Shader.Find("Custom/HightRipple")); material = GetComponent<MeshRenderer>().material; } private RenderTexture CreatRT() { var rt = new RenderTexture(1024, 1024, 0, RenderTextureFormat.RFloat); rt.Create(); return rt; } private Vector2 lastTexCoord; private void Update() { if (Input.GetMouseButton(0)) { RaycastHit hit; if (Physics.Raycast(camera.ScreenPointToRay(Input.mousePosition), out hit)) { if (Vector2.Distance(hit.textureCoord, lastTexCoord) >0.01f) { lastTexCoord = hit.textureCoord; DrawPoint(hit); } } } DrawRipple(); material.SetTexture("_RippleHightTex", _currentTexture); } private void DrawPoint(RaycastHit hit) { _point_material.SetFloat("_Radius", radius); _point_material.SetVector("_HitPos", hit.textureCoord); _point_material.SetTexture("_SourceTex", _currentTexture); Graphics.Blit(null, _tempTexture, _point_material); RenderTexture rt = _currentTexture; _currentTexture = _tempTexture; _tempTexture = rt; } private void DrawRipple() { _hightRipple.SetTexture("_SourceTex", _currentTexture); _hightRipple.SetTexture("_PrevTex", _prevTexture); Graphics.Blit(null, _tempTexture, _hightRipple); Graphics.Blit(_tempTexture, _prevTexture); RenderTexture rt = _prevTexture; _prevTexture = _currentTexture; _currentTexture = rt; } }

初始涟漪生成shader

Shader "Custom/GenerateRippleHight" { Properties { _MainTex ("Texture", 2D) = "white" {} } SubShader { Tags { "RenderType"="Opaque" } 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 pos : SV_POSITION; }; sampler2D _SourceTex; float4 _SourceTex_ST; float2 _HitPos; float _Radius; v2f vert (appdata v) { v2f o; o.pos = UnityObjectToClipPos(v.vertex); o.uv = TRANSFORM_TEX(v.uv, _SourceTex); return o; } fixed4 frag (v2f i) : SV_Target { fixed4 col = tex2D(_SourceTex, i.uv); float factor =max(0,_Radius-length(i.uv-_HitPos)/_Radius); col.r += min( factor,1); return col; } ENDCG } } }

涟漪扩散shader

Shader "Custom/HightRipple" { Properties { _MainTex ("Texture", 2D) = "white" {} } SubShader { Tags { "RenderType"="Opaque" } 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 pos : SV_POSITION; }; sampler2D _SourceTex; sampler2D _PrevTex; float4 _SourceTex_ST; float4 _SourceTex_TexelSize; v2f vert (appdata v) { v2f o; o.pos = UnityObjectToClipPos(v.vertex); o.uv = v.uv; return o; } fixed4 frag (v2f i) : SV_Target { float3 offset = float3(_SourceTex_TexelSize.xy,0); float col12 = tex2D(_SourceTex,i.uv + offset.zy ).x; float col10 = tex2D(_SourceTex,i.uv - offset.zy ).x; float col01 = tex2D(_SourceTex,i.uv - offset.xz ).x; float col21 = tex2D(_SourceTex,i.uv + offset.xz ).x; float col11 = tex2D(_PrevTex,i.uv).x; float finel = (col10 + col12 + col01 + col21)*0.5 - col11; finel = finel*0.99; return float4(finel,0,0,1); } ENDCG } } }

最终应用shader，简单的用了Blinn-Phong光照模型

Shader "Unlit/MeshRipple" { Properties { _MainTex ("Texture", 2D) = "white" {} _Specular ("_Specular", Color) = (1,1,1,1) _Diffuse ("_Diffuse", Color) = (1,1,1,1) _heigth2normalFactor ("_heigth2normalFactor", Range(0.01,100)) = 0.1 } SubShader { Tags { "RenderType" = "Opaque" "Queue" = "Transparent" } LOD 100 Blend SrcAlpha OneMinusSrcAlpha Pass { CGPROGRAM #pragma vertex vert #pragma fragment frag #include "UnityCG.cginc" #include "Lighting.cginc" struct appdata { float4 vertex : POSITION; float2 uv : TEXCOORD0; }; struct v2f { float2 uv : TEXCOORD0; float4 pos : SV_POSITION; float4 worldPos : TEXCOORD1; }; sampler2D _MainTex; float4 _MainTex_ST; sampler2D _RippleHightTex; float4 _RippleHightTex_TexelSize; float4 _Specular; float4 _Diffuse; float _heigth2normalFactor; float3 HigthToNormal(sampler2D heigthTex ,float2 heigth_TexelSize , float2 uv) { float3 offset = float3(heigth_TexelSize.xy,0); float factor = _heigth2normalFactor; float3 S = float3(1,0, (tex2D(heigthTex,uv + offset.xz).x - tex2D(heigthTex,uv - offset.xz).x)*factor); float3 T = float3(0,1, (tex2D(heigthTex,uv + offset.zy).x - tex2D(heigthTex,uv - offset.zy).x)*factor); float3 d = cross(S,T)+float3(0.5,0.5,1); return d; } v2f vert (appdata v) { v2f o; o.pos = UnityObjectToClipPos(v.vertex); o.worldPos = mul(unity_ObjectToWorld,v.vertex); o.uv = TRANSFORM_TEX(v.uv, _MainTex); return o; } float4 frag (v2f i) : SV_Target { float4 col = tex2D(_MainTex, i.uv)*_Diffuse; float3 normal = HigthToNormal(_RippleHightTex,_RippleHightTex_TexelSize.xy, i.uv); normal = normalize(normal); float3 worldLight = normalize(_WorldSpaceLightPos0.xyz); float3 view = normalize(_WorldSpaceCameraPos.xyz - i.worldPos.xyz); float3 halfDir = normalize(worldLight + view); float3 specular = _LightColor0.rgb * _Specular.rgb * pow(max(0,dot(normal, halfDir)), 4); col.rgb += specular; return col; } ENDCG } } }

知秋君

相关推荐