Unity教程之-Unity3d纹理贴图移动特效产生岩浆、瀑布效果

 

纹理贴图移动特效产生岩浆、瀑布效果实现原理是改变动态改变纹理坐标uv的值,使之移动

看下最终效果图

首先准备好一张贴图

建立一个shader
变量一览:
_MainTex 主纹理贴图
_MainTint 主要颜色
_ScrollXSpeed x轴移动速度
_ScrollYSpeed  y轴移动速度


Properties {
_MainTex ("Base (RGB)", 2D) = "white" {}
_MainTint ("Diffuse Tint", Color) = (1, 1, 1, 1)
_ScrollXSpeed ("X Scroll Speed", Range(0, 10)) = 2
_ScrollYSpeed ("Y Scroll Speed", Range(0, 10)) = 2
}

主要是在surf函数里进行操作
fixed xScrollValue = _ScrollXSpeed * _Time;
fixed yScrollValue = _ScrollYSpeed * _Time;
x、y偏移量随时间增加


void surf (Input IN, inout SurfaceOutput o) {
fixed2 scrolledUV = IN.uv_MainTex;
fixed xScrollValue = _ScrollXSpeed * _Time;
fixed yScrollValue = _ScrollYSpeed * _Time;
scrolledUV += fixed2(xScrollValue, yScrollValue);
half4 c = tex2D (_MainTex, scrolledUV);
o.Albedo = c.rgb * _MainTint;
o.Alpha = c.a;
}

_Time是 unity shaderlab内置值
float4 _Time : Time (t/20, t, t*2, t*3)
是一个四维向量

scrolledUV += fixed2(xScrollValue, yScrollValue);
uv的x,y值随时间累加偏移量

最后整合uv与主颜色到当前纹理上
产生了这种移动的效果

shader代码如下


Shader "Custom/testShader" {
Properties {
_MainTex ("Base (RGB)", 2D) = "white" {}
_MainTint ("Diffuse Tint", Color) = (1, 1, 1, 1)
_ScrollXSpeed ("X Scroll Speed", Range(0, 10)) = 2
_ScrollYSpeed ("Y Scroll Speed", Range(0, 10)) = 2
}
SubShader {
Tags { "RenderType"="Opaque" }
LOD 200

CGPROGRAM
#pragma surface surf Lambert
fixed4 _MainTint;
fixed _ScrollXSpeed;
fixed _ScrollYSpeed;
sampler2D _MainTex;

struct Input {
float2 uv_MainTex;
};

void surf (Input IN, inout SurfaceOutput o) {
fixed2 scrolledUV = IN.uv_MainTex;
fixed xScrollValue = _ScrollXSpeed * _Time;
fixed yScrollValue = _ScrollYSpeed * _Time;
scrolledUV += fixed2(xScrollValue, yScrollValue);
half4 c = tex2D (_MainTex, scrolledUV);
o.Albedo = c.rgb * _MainTint;
o.Alpha = c.a;
}
ENDCG
}
FallBack "Diffuse"
}

本篇unity教程到此结束