Rename decay to falloff in GlassHighlight.Dynamic, update docs

liquid-glass/src/main/java/com/kyant/liquidglass/dispersion/Dispersion.kt

@@ -3,15 +3,30 @@ package com.kyant.liquidglass.dispersion
 import androidx.annotation.FloatRange
 import androidx.compose.runtime.Immutable
 
+/**
+ * The dispersion effect applied to the liquid glass.
+ */
 @Immutable
 sealed interface Dispersion {
 
+    /**
+     * No dispersion effect.
+     */
     @Immutable
     data object None : Dispersion
 
+    /**
+     * Automatic dispersion effect, which adapts to the inner refraction options.
+     */
     @Immutable
     data object Automatic : Dispersion
 
+    /**
+     * A fractional dispersion effect, which disperses the glass by a fraction of its inner refraction options.
+     *
+     * @param fraction
+     * The fraction of the inner refraction options to disperse the glass by.
+     */
     @Immutable
     data class Fractional(
         @param:FloatRange(from = 0.0, to = 1.0) val fraction: Float

liquid-glass/src/main/java/com/kyant/liquidglass/highlight/GlassHighlight.kt

@@ -35,7 +35,7 @@ sealed interface GlassHighlight {
     }
 
     /**
-     * A no-op highlight effect.
+     * No highlight effect.
      */
     @Immutable
     data object None : GlassHighlight {
@@ -48,7 +48,7 @@ sealed interface GlassHighlight {
     }
 
     /**
-     * A solid highlight effect.
+     * Solid highlight effect.
      *
      * @param width
      * The width of the highlight.
@@ -67,7 +67,7 @@ sealed interface GlassHighlight {
     ) : GlassHighlight
 
     /**
-     * A dynamic highlight effect that creates a shimmering effect.
+     * Dynamic highlight effect with shimmering effect.
      *
      * @param width
      * The width of the highlight.
@@ -81,8 +81,8 @@ sealed interface GlassHighlight {
      * @param angle
      * The angle of the highlight in degrees.
      *
-     * @param decay
-     * The decay factor for the highlight, controlling how quickly it fades out.
+     * @param falloff
+     * The falloff of the highlight. Higher value results in a sharper highlight.
      */
     @Immutable
     data class Dynamic(
@@ -90,7 +90,7 @@ sealed interface GlassHighlight {
         override val color: Color = Color.White.copy(alpha = 0.4f),
         override val blendMode: BlendMode = BlendMode.Plus,
         val angle: Float = 45f,
-        @param:FloatRange(from = 0.0) val decay: Float = 1.5f
+        @param:FloatRange(from = 0.0) val falloff: Float = 1.5f
     ) : GlassHighlight {
 
         private var highlightShaderCache: RuntimeShader? = null
@@ -114,8 +114,8 @@ sealed interface GlassHighlight {
                         highlightShader.apply {
                             setFloatUniform("size", size.width, size.height)
                             setFloatUniform("cornerRadius", cornerRadius)
-                            setFloatUniform("angle", angle * PI.toFloat() / 180f)
-                            setFloatUniform("decay", decay)
+                            setFloatUniform("angle", angle * (PI / 180f).toFloat())
+                            setFloatUniform("falloff", falloff)
                         },
                         "image"
                     )

liquid-glass/src/main/java/com/kyant/liquidglass/utils/GlassShaders.kt

@@ -50,12 +50,11 @@ half4 main(float2 coord) {
     float2 halfSize = size * 0.5;
     float2 centeredCoord = coord - halfSize;
     float sd = sdRoundedRectangle(centeredCoord, halfSize, cornerRadius);
-    
     if (-sd >= refractionHeight) {
         return image.eval(coord);
     }
-    
     sd = min(sd, 0.0);
+    
     float maxGradRadius = max(min(halfSize.x, halfSize.y), cornerRadius);
     float gradRadius = min(cornerRadius * 1.5, maxGradRadius);
     float2 normal = gradSdRoundedRectangle(centeredCoord, halfSize, gradRadius);
@@ -91,16 +90,10 @@ half4 main(float2 coord) {
     float2 halfSize = size * 0.5;
     float2 centeredCoord = coord - halfSize;
     float sd = sdRoundedRectangle(centeredCoord, halfSize, cornerRadius);
-    
     if (-sd >= dispersionHeight) {
         return image.eval(coord);
     }
-    
     sd = min(sd, 0.0);
-    float maxGradRadius = max(min(halfSize.x, halfSize.y), cornerRadius);
-    float gradRadius = min(cornerRadius * 1.5, maxGradRadius);
-    float2 normal = gradSdRoundedRectangle(centeredCoord, halfSize, gradRadius);
-    float2 tangent = normalToTangent(normal);
     
     float dispersionDistance = circleMap(1.0 - -sd / dispersionHeight) * dispersionAmount;
     if (dispersionDistance < 2.0) {
@@ -108,6 +101,11 @@ half4 main(float2 coord) {
         return color;
     }
     
+    float maxGradRadius = max(min(halfSize.x, halfSize.y), cornerRadius);
+    float gradRadius = min(cornerRadius * 1.5, maxGradRadius);
+    float2 normal = gradSdRoundedRectangle(centeredCoord, halfSize, gradRadius);
+    float2 tangent = normalToTangent(normal);
+    
     half4 dispersedColor = half4(0.0);
     half4 weight = half4(0.0);
     float maxI = min(dispersionDistance, 20.0);
@@ -123,6 +121,7 @@ half4 main(float2 coord) {
         weight += mask;
     }
     dispersedColor /= weight;
+    
     dispersedColor.a = image.eval(coord).a;
     return dispersedColor;
 }"""
@@ -134,7 +133,7 @@ uniform shader image;
 uniform float2 size;
 uniform float cornerRadius;
 uniform float angle;
-uniform float decay;
+uniform float falloff;
 
 $sdRectangleShaderUtils
 
@@ -146,7 +145,7 @@ half4 main(float2 coord) {
     float2 topLightNormal = float2(-cos(angle), -sin(angle));
     float topLightFraction = dot(topLightNormal, grad);
     float bottomLightFraction = -topLightFraction;
-    float fraction = pow(max(topLightFraction, bottomLightFraction), decay);
+    float fraction = pow(max(topLightFraction, bottomLightFraction), falloff);
     
     return image.eval(coord) * fraction;
 }"""