Pixel-Composer/shaders/sh_shape/sh_shape.fsh
2024-05-25 09:51:52 +07:00

216 lines
6.5 KiB
GLSL

// 2D Signed Distance equations by InigoQuilez
varying vec2 v_vTexcoord;
varying vec4 v_vColour;
uniform int shape;
uniform int bg;
uniform int aa;
uniform int sides;
uniform int tile;
uniform int drawDF;
uniform vec2 dfLevel;
uniform float rotation;
uniform float angle;
uniform float inner;
uniform float outer;
uniform float corner;
uniform float stRad;
uniform float edRad;
uniform float parall;
uniform vec2 angle_range;
uniform vec2 dimension;
uniform vec2 center;
uniform vec2 scale;
uniform vec2 trep;
uniform vec4 bgColor;
#define PI 3.14159265359
#define TAU 6.283185307179586
float ndot(vec2 a, vec2 b ) { return a.x*b.x - a.y*b.y; }
float dot2(in vec2 v ) { return dot(v,v); }
float sdRegularPolygon(in vec2 p, in float r, in int n, in float ang ) {
// these 4 lines can be precomputed for a given shape
float an = PI / float(n);
vec2 acs = vec2(cos(an), sin(an));
// reduce to first sector
float bn = mod(atan(p.x, p.y) + PI - ang, 2.0 * an) - an;
p = length(p) * vec2(cos(bn), abs(sin(bn)));
// line sdf
p -= r * acs;
p.y += clamp( -p.y, 0.0, r * acs.y);
return length(p) * sign(p.x);
}
// signed distance to a n-star polygon with external angle en
float sdStar(in vec2 p, in float r, in int n, in float m, in float ang) { //m=[2,n]
// these 4 lines can be precomputed for a given shape
float an = PI / float(n);
float en = PI / m;
vec2 acs = vec2(cos(an), sin(an));
vec2 ecs = vec2(cos(en), sin(en)); // ecs=vec2(0,1) and simplify, for regular polygon,
// reduce to first sector
float bn = mod( atan(p.x, p.y) + PI - ang, 2.0 * an) - an;
p = length(p) * vec2(cos(bn), abs(sin(bn)));
// line sdf
p -= r * acs;
p += ecs * clamp( -dot(p, ecs), 0.0, r * acs.y / ecs.y);
return length(p)*sign(p.x);
}
// sca is the sin/cos of the orientation
// scb is the sin/cos of the aperture
float sdArc( in vec2 p, in vec2 sca, in vec2 scb, in float ra, in float rb ) {
p *= mat2(sca.x, sca.y, -sca.y, sca.x);
p.x = abs(p.x);
float k = (scb.y * p.x > scb.x * p.y) ? dot(p.xy,scb) : length(p);
return sqrt( dot(p, p) + ra * ra - 2.0 * ra * k ) - rb;
}
float sdRoundBox( in vec2 p, in vec2 b, in vec4 r ) {
r.xy = (p.x > 0.0)? r.xy : r.zw;
r.x = (p.y > 0.0)? r.x : r.y;
vec2 q = abs(p) - b + r.x;
return min(max(q.x, q.y), 0.0) + length(max(q, 0.0)) - r.x;
}
float sdBox( in vec2 p, in vec2 b ) {
vec2 d = abs(p) - b;
return length(max(d, 0.0)) + min(max(d.x, d.y), 0.0);
}
float sdTearDrop( vec2 p, float r1, float r2, float h ) {
p.x = abs(p.x);
float b = (r1 - r2) / h;
float a = sqrt(1.0 - b * b);
float k = dot(p, vec2(-b, a));
if( k < 0.0 ) return length(p) - r1;
if( k > a * h ) return length(p - vec2(0.0, h)) - r2;
return dot(p, vec2(a, b) ) - r1;
}
float sdCross( in vec2 p, in vec2 b, float r ) {
p = abs(p);
p = (p.y > p.x) ? p.yx : p.xy;
vec2 q = p - b;
float k = max(q.y, q.x);
vec2 w = (k > 0.0) ? q : vec2(b.y - p.x, -k);
return sign(k) * length(max(w, 0.0)) + r;
}
float sdVesica(vec2 p, float r, float d) {
p = abs(p);
float b = sqrt(r * r - d * d); // can delay this sqrt by rewriting the comparison
return ((p.y - b) * d > p.x * b) ? length(p - vec2(0.0, b)) * sign(d)
: length(p - vec2(-d, 0.0)) - r;
}
float sdCrescent(vec2 p, float s, float c, float a) {
float o = length(p) - 1.;
float i = length(p - vec2(cos(a) * (1. - s * c), sin(a) * (1. - s * c))) / s - 1.;
return max(o, -i);
}
float sdDonut(vec2 p, float s) {
float o = length(p) - 1.;
float i = length(p) / s - 1.;
return max(o, -i);
}
float sdRhombus( in vec2 p, in vec2 b ) {
p = abs(p);
float h = clamp( ndot(b - 2.0 * p,b) / dot(b, b), -1.0, 1.0 );
float d = length( p - 0.5 * b * vec2(1.0 - h, 1.0 + h) );
return d * sign( p.x * b.y + p.y * b.x - b.x * b.y );
}
float sdSegment( in vec2 p, in vec2 a, in vec2 b ) {
vec2 pa = p - a, ba = b - a;
float h = clamp( dot(pa, ba) / dot(ba, ba), 0.0, 1.0 );
return length( pa - ba * h );
}
float sdTrapezoid( in vec2 p, in float r1, float r2, float he ) {
vec2 k1 = vec2(r2, he);
vec2 k2 = vec2(r2 - r1, 2.0 * he);
p.x = abs(p.x);
vec2 ca = vec2(p.x - min(p.x, (p.y < 0.0)? r1 : r2), abs(p.y) - he);
vec2 cb = p - k1 + k2 * clamp( dot(k1 - p, k2) / dot2(k2), 0.0, 1.0 );
float s = (cb.x < 0.0 && ca.y < 0.0) ? -1.0 : 1.0;
return s * sqrt( min(dot2(ca), dot2(cb)) );
}
float sdParallelogram( in vec2 p, float wi, float he, float sk ) {
vec2 e = vec2(sk, he);
p = (p.y < 0.0)? -p : p;
vec2 w = p - e; w.x -= clamp(w.x, -wi, wi);
vec2 d = vec2(dot(w, w), -w.y);
float s = p.x * e.y - p.y * e.x;
p = (s < 0.0)? -p : p;
vec2 v = p - vec2(wi, 0); v -= e * clamp(dot(v, e) / dot(e, e), -1.0, 1.0);
d = min( d, vec2(dot(v, v), wi * he - abs(s)));
return sqrt(d.x) * sign(-d.y);
}
void main() {
float color = 0.;
vec2 coord = (v_vTexcoord - center) * mat2(cos(rotation), -sin(rotation), sin(rotation), cos(rotation)) / scale;
vec2 ratio = dimension / dimension.y;
float d;
if(tile == 1) coord = mod(coord + 1., 2.) - 1.;
if(shape == 0) {
d = sdBox( (v_vTexcoord - center) * mat2(cos(rotation), -sin(rotation), sin(rotation), cos(rotation)) * ratio, (scale * ratio - corner));
d -= corner;
} else if(shape == 1) {
d = length(coord) - 1.;
} else if(shape == 2) {
d = sdRegularPolygon( coord, 0.9 - corner, sides, angle );
d -= corner;
} else if(shape == 3) {
d = sdStar( coord, 0.9 - corner, sides, 2. + inner * (float(sides) - 2.), angle );
d -= corner;
} else if(shape == 4) d = sdArc( coord, vec2(sin(angle), cos(angle)), angle_range, 0.9 - inner, inner );
else if(shape == 5) d = sdTearDrop( coord + vec2(0., 0.5), stRad, edRad, 1. );
else if(shape == 6) d = sdCross( coord, vec2(1. + corner, outer), corner );
else if(shape == 7) d = sdVesica( coord, inner, outer );
else if(shape == 8) d = sdCrescent( coord, inner, outer, angle );
else if(shape == 9) d = sdDonut( coord, inner );
else if(shape == 10) d = sdRhombus( coord, vec2(1. - corner) ) - corner;
else if(shape == 11) d = sdTrapezoid( coord, trep.x - corner, trep.y - corner, 1. - corner ) - corner;
else if(shape == 12) d = sdParallelogram( coord, 1. - corner - parall, 1. - corner, parall) - corner;
if(drawDF == 1) {
color = -d;
color = (color - dfLevel.x) / (dfLevel.y - dfLevel.x);
} else if(aa == 0)
color = step(d, 0.0);
else
color = smoothstep(0.02, -0.02, d);
gl_FragColor = mix(bgColor, v_vColour, color);
}