SierpinskiGasket.HLSL

https://gyazo.com/9aa3f8f059c9af592706feeee83cd4eb

code:SielpinskiGasket.HLSL

float2 mod(float2 x, float y) {

return x - floor(x/y)*y;

}

float sdBox(float2 p, float2 s) {

float2 q = abs(p) - s;

float2 d = max(q, float2(.0));

return length(d) + min(max(q.x, q.y), 0.);

}

float sdCross(float2 p) {

p = abs(p);

return min(p.x, p.y) - 1.0;

}

float sierpinski(float2 p)

{

float d = sdBox(p, float2(1,1));

float s = 1.0;

for (int i = 0; i < 4; i++) {

float2 a = mod(p * s, 2.0) - 1.0;

float2 r = 1.0 - 3.0 * abs(a);

s *= 3.0;

float c = sdCross(r) / s;

d = max(d, c);

}

return d;

}

fixed4 frag (v2f i) : SV_Target

{

float2 p = 2*i.uv-1;

float d = sierpinski(p);

fixed4 col = (1).xxxx;

return col * d;

}