cvr-props/Assets/automata/GoL/gol.shader

75 lines
1.3 KiB
GLSL

Shader "CrispyPin/gol"
{
Properties
{
[NoScaleOffset]
_LastFrame ("Render texture", 2D) = "white" {}
}
SubShader
{
Tags { "RenderType"="Opaque" }
LOD 100
Pass
{
CGPROGRAM
#pragma vertex vert
#pragma fragment frag
#include "UnityCG.cginc"
#define WIDTH 256
struct appdata
{
float4 vertex : POSITION;
float2 uv : TEXCOORD0;
};
struct v2f
{
float2 uv : TEXCOORD0;
float4 vertex : SV_POSITION;
};
texture2D _LastFrame;
v2f vert (appdata v)
{
v2f o;
o.vertex = UnityObjectToClipPos(v.vertex);
o.uv = v.uv;
return o;
}
inline half state(uint2 p, int dx, int dy)
{
const uint x = (p.x + dx) % WIDTH;
const uint y = (p.y + dy) % WIDTH;
return _LastFrame[uint2(x, y)].b > 0;
}
fixed3 frag (v2f i) : SV_Target
{
if(_ProjectionParams.z > 1) discard;
const uint2 p = i.uv * WIDTH;
half count =
state(p, -1, -1) +
state(p, 0, -1) +
state(p, 1, -1) +
state(p, -1, 0) +
state(p, 1, 0) +
state(p, -1, 1) +
state(p, 0, 1) +
state(p, 1, 1);
half prev = _LastFrame[p].b > 0;
half next = count == 3 || ((count == 2) && prev);
return fixed3(i.uv * next, next * (_SinTime.y * 0.4 + 0.6));
}
ENDCG
}
}
}