unity 水冲击效果
时间: 2023-07-11 16:31:38 浏览: 45
在Unity中实现水冲击效果,可以使用Shader和一些计算技巧来实现。下面是一个简单的实现方法:
首先,在Shader中使用一张Noise贴图来控制水波的形状。然后,通过计算物体表面与水波的交点,来确定物体表面的变形程度。最后,使用变形后的表面位置来计算法线和UV坐标,从而实现水波的扭曲效果。
以下是一个简单的Shader代码示例,可以实现水冲击效果:
```
Shader "Custom/WaterImpact" {
Properties {
_MainTex ("Texture", 2D) = "white" {}
_NoiseTex ("Noise Texture", 2D) = "white" {}
_ImpactPosition ("Impact Position", Vector) = (0,0,0,0)
_ImpactRadius ("Impact Radius", Range(0,1)) = 0.5
_WaveHeight ("Wave Height", Range(0,1)) = 0.05
}
SubShader {
Tags {"Queue"="Transparent" "RenderType"="Transparent"}
LOD 200
Pass {
CGPROGRAM
#pragma vertex vert
#pragma fragment frag
#include "UnityCG.cginc"
struct appdata {
float4 vertex : POSITION;
float3 normal : NORMAL;
float2 uv : TEXCOORD0;
};
struct v2f {
float2 uv : TEXCOORD0;
float4 vertex : SV_POSITION;
float3 worldPos : TEXCOORD1;
float3 worldNormal : TEXCOORD2;
};
sampler2D _MainTex;
sampler2D _NoiseTex;
float4 _ImpactPosition;
float _ImpactRadius;
float _WaveHeight;
v2f vert (appdata v) {
v2f o;
// 计算变形后的表面位置
float3 impactPos = mul(unity_ObjectToWorld, _ImpactPosition).xyz;
float dist = length(v.vertex.xyz - impactPos) / _ImpactRadius;
float waveFactor = _WaveHeight * tex2D(_NoiseTex, v.uv * 10 + _Time.y * 0.1).r * smoothstep(1, 0, dist);
float3 deformedPos = v.vertex.xyz + v.normal * waveFactor;
// 计算法线和UV坐标
o.worldNormal = mul(unity_ObjectToWorld, float4(v.normal, 0)).xyz;
o.worldPos = mul(unity_ObjectToWorld, float4(deformedPos, 1)).xyz;
o.vertex = UnityObjectToClipPos(float4(deformedPos, 1));
o.uv = v.uv;
return o;
}
fixed4 frag (v2f i) : SV_Target {
// 使用变形后的法线计算光照
float3 worldNormal = normalize(i.worldNormal);
float3 worldViewDir = normalize(UnityWorldSpaceViewDir(i.worldPos));
float3 worldLightDir = normalize(UnityLightPosition0.xyz - i.worldPos);
half4 texColor = tex2D(_MainTex, i.uv);
half3 ambient = UNITY_LIGHTMODEL_AMBIENT.xyz;
half3 diffuse = texColor.rgb * _LightColor0.rgb * max(0,dot(worldNormal, worldLightDir));
half3 reflection = _LightColor0.rgb * texColor.rgb * pow(max(0, dot(reflect(-worldViewDir, worldNormal), worldLightDir)), 10);
return float4(ambient + diffuse + reflection, texColor.a);
}
ENDCG
}
}
FallBack "Diffuse"
}
```
在使用这个Shader时,需要在Material中设置_ImpactPosition、_ImpactRadius和_WaveHeight参数的值,从而控制冲击的位置、半径和波高。同时,需要准备一张Noise贴图用于控制水波的形状。