From cf5f8c211355c0beb9d47ddb59d4d58da5bafc6f Mon Sep 17 00:00:00 2001
From: Rezmason <jeremysachs@rezmason.net>
Date: Sat, 23 Oct 2021 01:12:31 -0700
Subject: [PATCH] Simplifying rainPass.compute's weirder operations.

---
 TODO.txt                 | 13 +++++--------
 js/config.js             |  2 +-
 shaders/rainPass.compute | 16 ++++++++++------
 3 files changed, 16 insertions(+), 15 deletions(-)

diff --git a/TODO.txt b/TODO.txt
index deb6f28..dc6e6a1 100644
--- a/TODO.txt
+++ b/TODO.txt
@@ -1,13 +1,10 @@
 TODO:
 
-Improve forkability
-  Refactor rainPass.compute's sin(sqrt(5)) stuff, there must be a clearer expression
-
-  Write an explanation of the rain pass (and include images)
-    Compute
-    Volumetric quads
-    Fullscreen quad and spacial mapping
-    MSDFs
+Write an explanation of the rain pass (and include images)
+  Compute
+  Volumetric quads
+  Fullscreen quad and spacial mapping
+  MSDFs
 
 Resurrection
   Modified glyph order?
diff --git a/js/config.js b/js/config.js
index 3e4a571..95b939f 100644
--- a/js/config.js
+++ b/js/config.js
@@ -72,7 +72,7 @@ const versions = {
 		bloomStrength: 0.75,
 		highPassThreshold: 0.0,
 		cycleSpeed: 0.2,
-		cycleFrameSkip: 6,
+		cycleFrameSkip: 8,
 		cycleStyleName: "cycleRandomly",
 		cursorEffectThreshold: 0.64,
 		brightnessOverride: 0.22,
diff --git a/shaders/rainPass.compute b/shaders/rainPass.compute
index 63680c0..51638fc 100644
--- a/shaders/rainPass.compute
+++ b/shaders/rainPass.compute
@@ -40,20 +40,24 @@ vec2 randomVec2( const in vec2 uv ) {
 	return fract(vec2(sin(uv.x * 591.32 + uv.y * 154.077), cos(uv.x * 391.32 + uv.y * 49.077)));
 }
 
+float wobble(float x) {
+	return x + 0.3 * sin(SQRT_2 * x) + 0.2 * sin(SQRT_5 * x);
+}
+
 // Core functions
 
 // Rain time is the shader's key underlying concept.
 // It's why glyphs that share a column are lit simultaneously, and are brighter toward the bottom.
 float getRainTime(float simTime, vec2 glyphPos) {
-	float columnTimeOffset = randomFloat(vec2(glyphPos.x, 0.));
-	float columnSpeedOffset = randomFloat(vec2(glyphPos.x + 0.1, 0.));
+	float columnTimeOffset = randomFloat(vec2(glyphPos.x, 0.)) * 1000.;
+	float columnSpeedOffset = randomFloat(vec2(glyphPos.x + 0.1, 0.)) * 0.5 + 0.5;
 	// columnSpeedOffset = 0.; // TODO: loop
-	float columnTime = (columnTimeOffset * 1000. + simTime * 0.5 * fallSpeed) * (0.5 + columnSpeedOffset * 0.5) + (sin(simTime * fallSpeed * columnSpeedOffset) * 0.2);
+	float columnTime = columnTimeOffset + simTime * fallSpeed * columnSpeedOffset;
 	return (glyphPos.y * 0.01 + columnTime) / raindropLength;
 }
 
 float getBrightness(float rainTime) {
-	float value = 1. - fract((rainTime + 0.3 * sin(SQRT_2 * rainTime) + 0.2 * sin(SQRT_5 * rainTime)));
+	float value = 1. - fract(wobble(rainTime));
 	// value = 1. - fract(rainTime); // TODO: loop
 	return log(value * 1.25) * 3.;
 }
@@ -79,7 +83,7 @@ float applySunShowerBrightness(float brightness, vec2 screenPos) {
 
 float applyThunderBrightness(float brightness, float simTime, vec2 screenPos) {
 	simTime *= 0.5;
-	float thunder = 1. - fract((simTime + 0.3 * sin(SQRT_2 * simTime) + 0.2 * sin(SQRT_5 * simTime)));
+	float thunder = 1. - fract(wobble(simTime));
 	// thunder = 1. - fract(simTime + 0.3); // TODO: loop
 
 	thunder = log(thunder * 1.5) * 4.;
@@ -93,7 +97,7 @@ float applyRippleEffect(float effect, float simTime, vec2 screenPos) {
 		return effect;
 	}
 
-	float rippleTime = (simTime * 0.5 + 0.2 * sin(simTime)) * rippleSpeed + 1.;
+	float rippleTime = (simTime * 0.5 + sin(simTime) * 0.2) * rippleSpeed + 1.; // TODO: clarify
 	// rippleTime = (simTime * 0.5) * rippleSpeed + 1.; // TODO: loop
 
 	vec2 offset = randomVec2(vec2(floor(rippleTime), 0.)) - 0.5;