Unity Shader实现图形绘制（蓝天白云大海）

unity shader学习：2d图形绘制(蓝天白云大海)，供大家参考，具体内容如下

基本是一些数学上的算法

shader部分:

shader "unlit/2d-ocean"
{
 properties
 {
 _maintex ("texture", 2d) = "white" {}
 _suncolor("suncolor",color) = (1,1,1,1)
 _sunroundcolor("sunroundcolor",color) = (1,0,0,1)
 _wavecolor1("wavecolor1",color) = (1,1,1,1)
 _wavecolor2("wavecolor2",color) = (1,1,1,1)
 _wavecolor3("wavecolor3",color) = (1,1,1,1)
 _wavecolor4("wavecolor4",color) = (1,1,1,1)
 _wavecolor5("wavecolor5",color) = (1,1,1,1)
 _skycolor("skycolor",color)=(0,1,0,1)
  _cloudpos1("cloudpos1",vector)=(0,0,0,0)
 _cloudpos2("cloudpos2",vector) = (0,0,0,0)
 _cloudpos3("cloudpos3",vector) = (0,0,0,0)
 _cloudpos4("cloudpos4",vector) = (0,0,0,0)
 _cloudpos5("cloudpos5",vector) = (0,0,0,0)
 _wavefactor1("wavefactor1",vector)=(0,0,0,0)
 _wavefactor2("wavefactor2",vector) = (0,0,0,0)
 _wavefactor3("wavefactor3",vector) = (0,0,0,0)
 _wavefactor4("wavefactor4",vector) = (0,0,0,0)
 _wavefactor5("wavefactor5",vector) = (0,0,0,0)
 _sunpos("sunpos",vector)=(0,0,0,0)
 _sunroundfactor("sunroundfactor",range(0.0,2.0)) = 0.1
 _sunsize("sunsize",range(0.0,1.0)) = 1.0
 }
 subshader
 {
 tags { "rendertype"="transparent" }
 lod 100

 blend srcalpha oneminussrcalpha
 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;
 float4 _cloudpos1;
 float4 _cloudpos2;
 float4 _cloudpos3;
 float4 _cloudpos4;
 float4 _cloudpos5;
 float4 _wavecolor1;
 float4 _wavecolor2;
 float4 _wavecolor3;
 float4 _wavecolor4;
 float4 _wavecolor5;
 float4 _wavefactor1;
 float4 _wavefactor2;
 float4 _wavefactor3;
 float4 _wavefactor4;
 float4 _wavefactor5;
 float4 _suncolor;
 float4 _sunroundcolor;
 float4 _sunpos;
 float _sunroundfactor;
 float _sunsize;
 float4 _skycolor;
 
 //画单个圆(uv,位置，大小，抗锯齿)
 float4 circle(float2 uv, float2 center, float size, float blur) {
 uv = uv - center;
 uv = uv / size;
 float len = length(uv);
 //长度大于一个半径单位透明度为0，小于透明度为1
 float val = smoothstep(1.0,1.0-blur, len);
 return float4(1, 1, 1, val);
 }

 //画单个云
 float4 drawcloud(float2 uv, float2 center, float size) {
 uv = uv - center;
 uv = uv / size;
 float4 col = circle(uv, float2(0.0, 0.0), 0.2, 1);
 //将圆中不想要的部分剪切掉
 col = col * smoothstep(-0.1, -0.1 + 0.01, uv.y);
 //圆摆放不同位置组成云
 col += circle(uv, float2(0.15, -0.05), 0.1, 1);
 col += circle(uv, float2(0.0, -0.1), 0.11, 1);
 col += circle(uv, float2(-0.15, -0.1), 0.1, 1);
 col += circle(uv, float2(-0.3, -0.08), 0.1, 1);
 col += circle(uv, float2(-0.2, 0.0), 0.15, 1);
 return col;
 }

 //画复数云
 float4 drawclouds(float2 uv) {
 uv.x += 0.03*_time.y;
 //使得左右连续
 uv.x = frac(uv.x + 0.5) - 0.5;
 float4 col = drawcloud(uv, _cloudpos1.xy, 0.1);
 col += drawcloud(uv, _cloudpos2.xy, 0.12);
 col += drawcloud(uv, _cloudpos3.xy, 0.14);
 col += drawcloud(uv, _cloudpos4.xy, 0.16);
 col += drawcloud(uv, _cloudpos5.xy, 0.18);
 return col;
 }

 //画太阳光环
 float4 drawsuncircle(float2 uv,float2 center,float size) {
 uv = uv - center;
 uv = uv / size;
 //atan2返回点(x,y)与x轴的夹角，范围(-π,π]
 //获取极坐标的θ角度
 float degree = atan2(uv.y , uv.x ) + _time.y * -0.1;
 //uv向量离中心点距离
 //获取极坐标的r=x2+y2开方
 float len = length(uv);
 //根据极坐标玫瑰线:r(θ)=a*sin(kθ)
 //求得r;a为扩散幅度，k为花瓣数*0.5
 float r = 0.3*abs(sin(degree*5.0));
 //画花瓣
 //保留r值小于到中心点距离的所有像素
 float sunround= smoothstep(r + 0.1 + _sunroundfactor, r + _sunroundfactor, len);
 return float4(1,1,1,sunround)*_sunroundcolor;
 }

 //画波浪(参数:uv,频率,振幅,整体高度,移动速度)
 float4 drawwave(float2 uv,float wavefrequency,float waveamplitude,float waveheight,float speed) {
 uv.x += speed * _time.y;
 uv.y += sin(_time.y+waveheight)*0.02;
 //uv.y大于sin函数的部分透明度为0，小于的部分透明度为1
 float val = uv.y - sin(uv.x*wavefrequency)*waveamplitude - waveheight;
 val = smoothstep(0.001,0.0, val);
 return float4(1, 1, 1, val);
 }

 //画背景
 float4 drawbackground(float2 uv) {
 float4 val = lerp(float4(1,1,1,1), _skycolor, uv.y);
 return val;
 }

 //混合图层(b为前景,a为背景)
 float4 lerpimages(float4 a, float4 b) {
 return float4(lerp(a, b, b.a).rgb, a.a + b.a);
 }

 v2f vert (appdata v)
 {
 v2f o;
 o.vertex = unityobjecttoclippos(v.vertex);
 o.uv = transform_tex(v.uv, _maintex);
 return o;
 }
 
 float4 frag (v2f i) : sv_target
 { 
 //太阳中心
 float4 suncorecolor = circle(i.uv, _sunpos.xy, _sunsize, 0.05)*_suncolor;
 //太阳光环
 float4 sunaroundcolor = drawsuncircle(i.uv, _sunpos.xy, _sunsize);
 //云
 float4 cloudscolor = drawclouds(i.uv);
 //波浪
 float4 wave1 = drawwave(i.uv, _wavefactor1.x, _wavefactor1.y, _wavefactor1.z, _wavefactor1.w)*_wavecolor1;
 float4 wave2 = drawwave(i.uv, _wavefactor2.x, _wavefactor2.y, _wavefactor2.z, _wavefactor2.w)*_wavecolor2;
 float4 wave3 = drawwave(i.uv, _wavefactor3.x, _wavefactor3.y, _wavefactor3.z, _wavefactor3.w)*_wavecolor3;
 float4 wave4 = drawwave(i.uv, _wavefactor4.x, _wavefactor4.y, _wavefactor4.z, _wavefactor4.w)*_wavecolor4;
 float4 wave5 = drawwave(i.uv, _wavefactor5.x, _wavefactor5.y, _wavefactor5.z, _wavefactor5.w)*_wavecolor5;
 //背景
 float4 backgroundcolor = drawbackground(i.uv);
 //图层叠加
 float4 finalcolor = lerpimages(backgroundcolor, sunaroundcolor);
 finalcolor = lerpimages(finalcolor, suncorecolor);
 finalcolor= lerpimages(finalcolor, wave1);
 finalcolor = lerpimages(finalcolor, wave2);
 finalcolor = lerpimages(finalcolor, wave3);
 finalcolor = lerpimages(finalcolor, wave4);
 finalcolor = lerpimages(finalcolor, wave5);
 finalcolor = lerpimages(finalcolor, cloudscolor);
 return finalcolor;
 }
 endcg
 }
 }
}

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。