【Shader】绘制攻击范围

效果图

实现

void surf (Input IN, inout SurfaceOutput o) {
fixed4 c;
IN.uv_MainTex = IN.uv_MainTex - float2(0.5, 0.5);  //移动圆心到中间【默认情况圆心在左下角】
float dis = sqrt(IN.uv_MainTex.x * IN.uv_MainTex.x + IN.uv_MainTex.y * IN.uv_MainTex.y); //计算半径
if(dis>_Border){
    c = float4(1, 1, 1, 1);
}else if(dis<_Border && dis<_Border-_Width){
 c = float4(1, 1, 1, 1);
}else{
    c = float4(1, 0, 0, 1);
}
o.Albedo = c.rgb;
o.Alpha = 1;
}