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-rw-r--r--shaders/post/glitch.glsl64
-rw-r--r--shaders/post/ripple.glsl52
2 files changed, 0 insertions, 116 deletions
diff --git a/shaders/post/glitch.glsl b/shaders/post/glitch.glsl
deleted file mode 100644
index 8f420d9c..00000000
--- a/shaders/post/glitch.glsl
+++ /dev/null
@@ -1,64 +0,0 @@
-// Glitch: now and then the signal slips. At the default level, every couple
-// of seconds a short
-// burst tears a few horizontal bands sideways and pulls their red and blue
-// apart; the bands are sized in pixels and the burst eases in and out over
-// a fraction of a second, so it reads as one event rather than a flicker,
-// and it looks the same at 60 or 144 Hz because every step is keyed to
-// iTime, not to frames. Between bursts the page is left exactly as it is.
-// A torn band's brightness dips in linear light. It is a Shadertoy file:
-// pardes puts its prefix before it.
-
-// Each at levels 1, 2 and 3 (`Glitch 1`..`Glitch 3`); 2 is the default. A
-// higher level slips more often and harder.
-float period() { return pardesByLevel(4.5, 2.4, 0.55); } // seconds between bursts, on average
-float burst() { return pardesByLevel(0.2, 0.28, 0.5); } // seconds a burst lasts
-float stepHz() { return pardesByLevel(20.0, 24.0, 30.0); } // how often a burst re-tears
-float shiftPx() { return pardesByLevel(8.0, 14.0, 34.0); }
-float splitPx() { return pardesByLevel(1.5, 2.5, 6.0); }
-float dip() { return pardesByLevel(0.08, 0.12, 0.22); }
-float tearFrom() { return pardesByLevel(0.8, 0.72, 0.35); } // how few bands tear
-
-float hash(vec2 p) {
- vec3 q = fract(vec3(p.xyx) * 0.1031);
- q += dot(q, q.yzx + 33.33);
- return fract((q.x + q.y) * q.z);
-}
-
-vec3 toLinear(vec3 c) {
- return mix(pow((c + 0.055) / 1.055, vec3(2.4)), c / 12.92, lessThanEqual(c, vec3(0.04045)));
-}
-
-vec3 toSrgb(vec3 c) {
- c = max(c, vec3(0.0));
- return mix(1.055 * pow(c, vec3(1.0 / 2.4)) - 0.055, c * 12.92, lessThanEqual(c, vec3(0.0031308)));
-}
-
-void mainImage(out vec4 fragColor, in vec2 fragCoord) {
- vec2 size = iResolution.xy;
- vec2 uv = fragCoord / size;
- // Which burst window this is, when in it the burst starts, and how far
- // into the burst we are: 0 outside one.
- float window = floor(iTime / period());
- float start = window * period() + hash(vec2(window, 7.0)) * (period() - burst());
- float t = (iTime - start) / burst();
- float live = step(0.0, t) * step(t, 1.0);
- float envelope = live * sin(3.14159265 * clamp(t, 0.0, 1.0));
- if (envelope <= 0.0) {
- fragColor = texture(iChannel0, uv);
- return;
- }
- // Bands of 6 to 40 px, re-cut at stepHz() during the burst; about one
- // band in four tears.
- float tick = floor(iTime * stepHz());
- float band_px = mix(6.0, 40.0, hash(vec2(tick, 3.0)));
- float band = floor(fragCoord.y / band_px);
- float roll = hash(vec2(band, tick));
- float tear = smoothstep(tearFrom(), tearFrom() + 0.18, roll) * envelope;
- float shift = (hash(vec2(tick, band + 11.0)) - 0.5) * 2.0 * shiftPx() * tear;
- vec2 at = vec2(fragCoord.x + shift, fragCoord.y);
- vec2 split = vec2(splitPx() * tear, 0.0);
- vec4 center = texture(iChannel0, at / size);
- vec3 col = vec3(texture(iChannel0, (at + split) / size).r, center.g, texture(iChannel0, (at - split) / size).b);
- col = toSrgb(toLinear(col) * (1.0 - dip() * tear));
- fragColor = vec4(col, center.a);
-}
diff --git a/shaders/post/ripple.glsl b/shaders/post/ripple.glsl
deleted file mode 100644
index 3236d339..00000000
--- a/shaders/post/ripple.glsl
+++ /dev/null
@@ -1,52 +0,0 @@
-// Ripple: the page as a still pool a slow swell crosses. Rings travel out
-// from the middle of the window at a fixed speed in pixels, so they look
-// the same at any size and frame rate; at the default level the displacement
-// is at most a couple of pixels, so text stays readable, and it eases in over its first half
-// second instead of snapping on. Each ring catches the light a little on its
-// rising side, in linear light, and the result is dithered so the shading
-// never bands. It is a Shadertoy file: pardes puts its prefix before it.
-
-const float TAU = 6.28318530718;
-const float EASE_IN = 0.5; // seconds
-
-// Each at levels 1, 2 and 3 (`Ripple 1`..`Ripple 3`); 2 is the default.
-float wavelengthPx() { return pardesByLevel(170.0, 150.0, 120.0); }
-float speedPx() { return pardesByLevel(40.0, 55.0, 80.0); } // outward, per second
-float amplitudePx() { return pardesByLevel(1.2, 2.2, 5.0); }
-float shade() { return pardesByLevel(0.02, 0.035, 0.09); } // light on a slope, linear
-float reachEnd() { return pardesByLevel(0.85, 0.95, 1.3); } // how far out it dies away
-
-vec3 toLinear(vec3 c) {
- return mix(pow((c + 0.055) / 1.055, vec3(2.4)), c / 12.92, lessThanEqual(c, vec3(0.04045)));
-}
-
-vec3 toSrgb(vec3 c) {
- c = max(c, vec3(0.0));
- return mix(1.055 * pow(c, vec3(1.0 / 2.4)) - 0.055, c * 12.92, lessThanEqual(c, vec3(0.0031308)));
-}
-
-float ign(vec2 p) {
- return fract(52.9829189 * fract(dot(p, vec2(0.06711056, 0.00583715))));
-}
-
-void mainImage(out vec4 fragColor, in vec2 fragCoord) {
- vec2 size = iResolution.xy;
- vec2 center = 0.5 * size;
- vec2 offset = fragCoord - center;
- float radius = length(offset);
- float reach = 0.5 * length(size);
- // Strongest a third of the way out, fading to nothing at the middle
- // and at the edges, so the window's frame never wobbles.
- float envelope = smoothstep(0.0, 0.18, radius / reach) * (1.0 - smoothstep(0.35, reachEnd(), radius / reach));
- float ease = smoothstep(0.0, EASE_IN, iTime);
- float phase = (radius - iTime * speedPx()) * TAU / wavelengthPx();
- float height = sin(phase);
- float slope = cos(phase);
- vec2 dir = offset / max(radius, 1e-3);
- vec2 moved = fragCoord + dir * height * amplitudePx() * envelope * ease;
-
- vec4 s = texture(iChannel0, moved / size);
- vec3 col = toLinear(s.rgb) * (1.0 + shade() * slope * envelope * ease);
- vec3 srgb = toSrgb(col) + (ign(fragCoord + float(iFrame % 64) * 5.588238) - 0.5) / 255.0;
- fragColor = vec4(clamp(srgb, 0.0, 1.0), s.a);
-}