From e70b55ff58fe187b3817824e54d7c7d3e632f8eb Mon Sep 17 00:00:00 2001
From: CrispyPin <crispin@tasa.se>
Date: Sun, 12 Feb 2023 16:34:03 +0100
Subject: [PATCH] normal based water reflection

---
 Assets/sunset_box/Sunset Env.mat            |  3 ++-
 Assets/sunset_box/sunset_env_dynamic.shader | 30 +++++++++++----------
 2 files changed, 18 insertions(+), 15 deletions(-)

diff --git a/Assets/sunset_box/Sunset Env.mat b/Assets/sunset_box/Sunset Env.mat
index 8c8f500..541f423 100644
--- a/Assets/sunset_box/Sunset Env.mat	
+++ b/Assets/sunset_box/Sunset Env.mat	
@@ -84,7 +84,7 @@ Material:
     - _SunAngle: 0
     - _SunCutoff: 0.06
     - _SunRadius: 0.06
-    - _Temp: 0.594
+    - _Temp: 0.826
     - _UVSec: 0
     - _ZWrite: 1
     m_Colors:
@@ -93,3 +93,4 @@ Material:
     - _HorizonCol: {r: 0.43, g: 0.27, b: 0.49, a: 1}
     - _SkyCol: {r: 0.22, g: 0.23, b: 0.58, a: 1}
     - _SunCol: {r: 1, g: 0.65, b: 0.05, a: 1}
+    - _WaterCol: {r: 0, g: 0, b: 0, a: 1}
diff --git a/Assets/sunset_box/sunset_env_dynamic.shader b/Assets/sunset_box/sunset_env_dynamic.shader
index 831af73..fee4381 100644
--- a/Assets/sunset_box/sunset_env_dynamic.shader
+++ b/Assets/sunset_box/sunset_env_dynamic.shader
@@ -21,10 +21,11 @@
 		_StarSizeRandom ("Star size randomness", Range(0, 1)) = 0.5
 		_StarTint ("Star tint", Range(0, 1)) = 0.4
 		[Header(Water)]
+		_WaterCol ("Water color", Color) = (0.03, 0.08, 0.12, 1.0)
 		_WaterSurface ("Surface Normal", 2D) = "white" {}
+		_Temp ("Wave scale", Range(0, 1)) = 0
 		[Header(Debug)]
 		_Grid ("Grid visibility", Range(0, 1)) = 0
-		_Temp ("Test", Range(0, 1)) = 0
 
 	}
 	SubShader
@@ -53,12 +54,11 @@
 			struct v2f
 			{
 				float4 vertex : SV_POSITION;
-				float3 camPos : TEXCOORD1;
-				float3 hitPos : TEXCOORD2;
+				float3 cam_pos : TEXCOORD0;
+				float3 hit_pos : TEXCOORD1;
 			};
 
 			sampler2D _MainTex;
-			sampler2D _WaterSurface;
 			fixed4 _SkyCol;
 			fixed4 _HorizonCol;
 
@@ -74,6 +74,9 @@
 			float _SunAngle;
 			float _SunRadius;
 			float _SunCutoff;
+
+			sampler2D _WaterSurface;
+			fixed4 _WaterCol;
 			float _Temp;
 
 			float _Grid;
@@ -82,30 +85,29 @@
 			{
 				v2f o;
 				o.vertex = UnityObjectToClipPos(v.vertex);
-				o.camPos = _WorldSpaceCameraPos;
-				o.hitPos = mul(unity_ObjectToWorld, v.vertex);
+				o.cam_pos = _WorldSpaceCameraPos;
+				o.hit_pos = mul(unity_ObjectToWorld, v.vertex);
 				return o;
 			}
 
 			fixed4 frag (v2f i) : SV_Target
 			{
-				fixed4 water_mod = 1.0;
+				float water_mod = 0.0;
 
-				float3 real_dir = normalize(i.hitPos - i.camPos);
+				float3 real_dir = normalize(i.hit_pos - i.cam_pos);
 				float3 dir = real_dir;
 				float real_y = asin(dir.y);
 				if (real_y < 0.0) { // distort to look like water reflection
-					float3 camera_local_pos = i.camPos + mul(unity_WorldToObject, float4(0, 0, 0, 1));
+					float3 camera_local_pos = i.cam_pos + mul(unity_WorldToObject, float4(0, 0, 0, 1));
 					float3 surface_pos = float3 (
 						camera_local_pos.x - camera_local_pos.y / (real_dir.y / real_dir.x),
 						0.0,
 						camera_local_pos.z - camera_local_pos.y / (real_dir.y / real_dir.z)
 					);
-					float3 water_normal = normalize ((tex2D(_WaterSurface, surface_pos.xz * 0.05) - 0.5).zxy );
-					water_normal = lerp(UP, water_normal, _Temp);
-					dir = reflect(dir, water_normal);
+					float3 water_normal = normalize((tex2D(_WaterSurface, surface_pos.xz * _Temp) - 0.5).zxy);
 
-					// water_mod = fixed4(0.4, 0.7, 0.8, 1.0);
+					dir = reflect(dir, water_normal);
+					water_mod = dot(dir, water_normal);
 				}
 				float y = abs(real_y);
 				dir.y = abs(dir.y);
@@ -162,7 +164,7 @@
 
 				col = lerp(col, _SunCol, sun_amount);
 
-				col *= water_mod;
+				col = lerp(col, _WaterCol, water_mod);
 
 				// debug, this should not be visible
 				if (dir.y < 0) {