underwater caustics

WickedEngine/shaders/ShaderInterop_Weather.h

@@ -276,9 +276,9 @@ struct ShaderOcean
 {
 	float4 water_color;
 	float water_height;
-	float patch_size;
 	float patch_size_rcp;
 	int texture_displacementmap;
+	int texture_gradientmap;
 };
 
 struct ShaderWeather
@@ -286,12 +286,14 @@ struct ShaderWeather
 	float3 sun_color;
 	float sun_energy;
 	float3 sun_direction;
-	float sky_exposure;
+	uint most_important_light_index;
 	float3 horizon;
-	float cloudiness;
+	float sky_exposure;
 	float3 zenith;
-	float cloud_scale;
+	float cloudiness;
 	float3 ambient;
+	float cloud_scale;
+	float3 padding;
 	float cloud_speed;
 
 	ShaderFog fog;

WickedEngine/shaders/globals.hlsli

@@ -505,6 +505,16 @@ inline float3 reconstruct_position(in float2 uv, in float z)
 	return reconstruct_position(uv, z, GetCamera().inverse_view_projection);
 }
 
+// Caustic pattern from: https://www.shadertoy.com/view/XtKfRG
+inline float caustic_pattern(float2 uv, float time)
+{
+	float3 k = float3(uv, time);
+	float3x3 m = float3x3(-2, -1, 2, 3, -2, 1, 1, 2, 2);
+	float3 a = mul(k, m) * 0.5;
+	float3 b = mul(a, m) * 0.4;
+	float3 c = mul(b, m) * 0.3;
+	return pow(min(min(length(0.5 - frac(a)), length(0.5 - frac(b))), length(0.5 - frac(c))), 7) * 25.;
+}
 
 // Convert texture coordinates on a cubemap face to cubemap sampling coordinates:
 // uv			: UV texture coordinates on cubemap face in range [0, 1]

WickedEngine/shaders/lightingHF.hlsli

@@ -115,7 +115,6 @@ inline float3 shadow_cube(in ShaderEntity light, in float3 L, in float3 Lunnorma
 	return shadow;
 }
 
-
 inline void light_directional(in ShaderEntity light, in Surface surface, inout Lighting lighting, in float shadow_mask = 1)
 {
 	float3 L = light.GetDirection();
@@ -187,6 +186,25 @@ inline void light_directional(in ShaderEntity light, in Surface surface, inout L
 
 			lighting.direct.diffuse = mad(light_color, BRDF_GetDiffuse(surface, surface_to_light), lighting.direct.diffuse);
 			lighting.direct.specular = mad(light_color, BRDF_GetSpecular(surface, surface_to_light), lighting.direct.specular);
+
+#ifndef WATER
+			const ShaderOcean ocean = GetWeather().ocean;
+			if (ocean.texture_displacementmap >= 0)
+			{
+				Texture2D displacementmap = bindless_textures[ocean.texture_displacementmap];
+				float2 ocean_uv = surface.P.xz * ocean.patch_size_rcp;
+				float3 displacement = displacementmap.SampleLevel(sampler_linear_wrap, ocean_uv, 0).xzy;
+				float water_height = ocean.water_height + displacement.y;
+				if (surface.P.y < water_height)
+				{
+					float3 caustic = caustic_pattern(ocean_uv * 20, GetFrame().time);
+					caustic *= sqr(saturate((water_height - surface.P.y) * 0.5)); // fade out at shoreline
+					caustic *= light_color;
+					lighting.indirect.diffuse += caustic;
+				}
+			}
+#endif // WATER
+
 		}
 	}
 }

WickedEngine/shaders/oceanSurfacePS.hlsl

@@ -2,6 +2,7 @@
 #define DISABLE_ENVMAPS
 #define DISABLE_TRANSPARENT_SHADOWMAP
 #define TRANSPARENT
+#define WATER
 #include "globals.hlsli"
 #include "oceanSurfaceHF.hlsli"
 #include "objectHF.hlsli"
@@ -19,6 +20,10 @@ float4 main(PSIn input) : SV_TARGET
 	V /= dist;
 	float emissive = 0;
 
+	float ocean_level_at_camera_pos = xOceanWaterHeight;
+	ocean_level_at_camera_pos += texture_ocean_displacementmap.SampleLevel(sampler_linear_wrap, GetCamera().position.xz * xOceanPatchSizeRecip, 0).z; // texture contains xzy!
+	const bool camera_above_water = GetCamera().position.y > ocean_level_at_camera_pos;
+
 	const float gradient_fade = saturate(dist * 0.001);
 	const float4 gradientNear = texture_gradientmap.Sample(sampler_aniso_wrap, input.uv);
 	const float4 gradientFar = texture_gradientmap.Sample(sampler_aniso_wrap, input.uv * 0.125);
@@ -31,7 +36,7 @@ float4 main(PSIn input) : SV_TARGET
 	surface.pixel = input.pos.xy;
 	float depth = input.pos.z;
 	surface.albedo = color.rgb;
-	surface.f0 = 0.02;
+	surface.f0 = camera_above_water ? 0.02 : 0.1;
 	surface.roughness = 0.1;
 	surface.P = input.pos3D;
 	surface.N = normalize(float3(gradient.x, xOceanTexelLength * 2, gradient.y));
@@ -46,6 +51,7 @@ float4 main(PSIn input) : SV_TARGET
 	TiledLighting(surface, lighting);
 
 	float2 ScreenCoord = surface.pixel * GetCamera().internal_resolution_rcp;
+	const float bump_strength = camera_above_water ? 0.04 : 0.1;
 
 	[branch]
 	if (GetCamera().texture_reflection_index >= 0)
@@ -53,21 +59,19 @@ float4 main(PSIn input) : SV_TARGET
 		//REFLECTION
 		float4 reflectionPos = mul(GetCamera().reflection_view_projection, float4(input.pos3D, 1));
 		float2 reflectionUV = clipspace_to_uv(reflectionPos.xy / reflectionPos.w);
-		float4 reflectiveColor = bindless_textures[GetCamera().texture_reflection_index].SampleLevel(sampler_linear_mirror, reflectionUV + surface.N.xz * 0.04f, 0);
+		float4 reflectiveColor = bindless_textures[GetCamera().texture_reflection_index].SampleLevel(sampler_linear_mirror, reflectionUV + surface.N.xz * bump_strength, 0);
 		lighting.indirect.specular = reflectiveColor.rgb * surface.F;
 	}
 
 	[branch]
 	if (GetCamera().texture_refraction_index >= 0)
 	{
-		// WATER REFRACTION 
+		// WATER REFRACTION
 		Texture2D texture_refraction = bindless_textures[GetCamera().texture_refraction_index];
-		float sampled_lineardepth = texture_lineardepth.SampleLevel(sampler_point_clamp, ScreenCoord.xy + surface.N.xz * 0.04f, 0) * GetCamera().z_far;
+		float sampled_lineardepth = texture_lineardepth.SampleLevel(sampler_point_clamp, ScreenCoord.xy + surface.N.xz * bump_strength, 0) * GetCamera().z_far;
 		float depth_difference = sampled_lineardepth - lineardepth;
-		surface.refraction.rgb = texture_refraction.SampleLevel(sampler_linear_mirror, ScreenCoord.xy + surface.N.xz * 0.04f * saturate(0.5 * depth_difference), 0).rgb;
-		float ocean_level_at_camera_pos = xOceanWaterHeight;
-		ocean_level_at_camera_pos += texture_ocean_displacementmap.SampleLevel(sampler_linear_wrap, GetCamera().position.xz * xOceanPatchSizeRecip, 0).z; // texture contains xzy!
-		if (GetCamera().position.y > ocean_level_at_camera_pos)
+		surface.refraction.rgb = texture_refraction.SampleLevel(sampler_linear_mirror, ScreenCoord.xy + surface.N.xz * bump_strength * saturate(0.5 * depth_difference), 0).rgb;
+		if (camera_above_water)
 		{
 			if (depth_difference < 0)
 			{
@@ -85,7 +89,7 @@ float4 main(PSIn input) : SV_TARGET
 	}
 
 	// Blend out at distance:
-	color.a = pow(saturate(1 - saturate(dist / GetCamera().z_far)), 2);
+	color.a = saturate(1 - saturate(dist / GetCamera().z_far - 0.8) * 5.0); // fade will be on edge and inwards 20%
 	color.a = lerp(0, color.a, saturate(pow(lineardepth, 2))); // fade when very close to camera
 
 	ApplyLighting(surface, lighting, color);

WickedEngine/shaders/oceanSurfaceVS.hlsl

@@ -30,6 +30,8 @@ PSIn main(uint vertexID : SV_VertexID)
 	{
 		// Displace surface:
 		float3 displacement = texture_displacementmap.SampleLevel(sampler_linear_wrap, uv, 0).xzy;
+		float dist = length(worldPos - GetCamera().position);
+		displacement *= saturate(1 - saturate(dist / GetCamera().z_far - 0.8) * 5.0); // fade will be on edge and inwards 20%
 		worldPos += displacement;
 	}
 

WickedEngine/shaders/shadowPS_water.hlsl

@@ -25,28 +25,7 @@ float4 main(PixelInput input) : SV_TARGET
 
 	color.rgb = 1; // disable water shadow because it has already fog
 
-	[branch]
-	if (GetMaterial().uvset_normalMap >= 0)
-	{
-		float3 bumpColor;
-
-		float2 bumpColor0 = 0;
-		float2 bumpColor1 = 0;
-		float2 bumpColor2 = 0;
-		const float2 UV_normalMap = GetMaterial().uvset_normalMap == 0 ? input.uvsets.xy : input.uvsets.zw;
-		bumpColor0 = 2.0f * texture_normalmap.Sample(sampler_objectshader, UV_normalMap - GetMaterial().texMulAdd.ww).rg - 1.0f;
-		bumpColor1 = 2.0f * texture_normalmap.Sample(sampler_objectshader, UV_normalMap + GetMaterial().texMulAdd.zw).rg - 1.0f;
-		bumpColor = float3(bumpColor0 + bumpColor1 + bumpColor2, 1)  * GetMaterial().refraction;
-		bumpColor.rg *= GetMaterial().normalMapStrength;
-		bumpColor = normalize(max(bumpColor, float3(0, 0, 0.0001f)));
-
-		float caustic = abs(dot(bumpColor, float3(0, 1, 0)));
-		caustic = saturate(caustic);
-		caustic = pow(caustic, 2);
-		caustic *= 20;
-
-		color.rgb += caustic;
-	}
+	color.rgb += caustic_pattern(input.uvsets.xy * 20, GetFrame().time);
 
 	color.a = input.pos.z; // secondary depth
 

WickedEngine/shaders/underwaterCS.hlsl

@@ -1,6 +1,7 @@
 #include "globals.hlsli"
 #include "ShaderInterop_Postprocess.h"
 #include "oceanSurfaceHF.hlsli"
+#include "lightingHF.hlsli"
 
 PUSHCONSTANT(postprocess, PostProcess);
 
@@ -52,7 +53,7 @@ void main(uint3 DTid : SV_DispatchThreadID)
 		const float ocean_dist = length(ocean_surface_pos - o);
 
 		const float min_dist = min(lineardepth, ocean_dist);
-		float3 modified_color = lerp(color.rgb, ocean.water_color.rgb, saturate(0.5 + min_dist * 0.025));
+		float3 modified_color = lerp(color.rgb, ocean.water_color.rgb, saturate(0.5 + min_dist * 0.025 * ocean.water_color.a));
 		color.rgb = lerp(color.rgb, modified_color, pow(saturate(ocean_pos.y - world_pos.y), 0.25));
 	}
 	output[DTid.xy] = color;

WickedEngine/wiScene.cpp

@@ -1862,6 +1862,7 @@ namespace wi::scene
 		shaderscene.weather.sun_color = weather.sunColor;
 		shaderscene.weather.sun_direction = weather.sunDirection;
 		shaderscene.weather.sun_energy = weather.sunEnergy;
+		shaderscene.weather.most_important_light_index = weather.most_important_light_index;
 		shaderscene.weather.ambient = weather.ambient;
 		shaderscene.weather.cloudiness = weather.cloudiness;
 		shaderscene.weather.cloud_scale = weather.cloudScale;
@@ -1882,9 +1883,9 @@ namespace wi::scene
 		shaderscene.weather.volumetric_clouds = weather.volumetricCloudParameters;
 		shaderscene.weather.ocean.water_color = weather.oceanParameters.waterColor;
 		shaderscene.weather.ocean.water_height = weather.oceanParameters.waterHeight;
-		shaderscene.weather.ocean.patch_size = weather.oceanParameters.patch_length;
 		shaderscene.weather.ocean.patch_size_rcp = 1.0f / weather.oceanParameters.patch_length;
 		shaderscene.weather.ocean.texture_displacementmap = device->GetDescriptorIndex(ocean.getDisplacementMap(), SubresourceType::SRV);
+		shaderscene.weather.ocean.texture_gradientmap = device->GetDescriptorIndex(ocean.getGradientMap(), SubresourceType::SRV);
 
 		shaderscene.ddgi.color_texture = device->GetDescriptorIndex(&ddgiColorTexture[0], SubresourceType::SRV);
 		shaderscene.ddgi.depth_texture = device->GetDescriptorIndex(&ddgiDepthTexture[0], SubresourceType::SRV);

WickedEngine/wiVersion.cpp

@@ -9,7 +9,7 @@ namespace wi::version
 	// minor features, major updates, breaking compatibility changes
 	const int minor = 60;
 	// minor bug fixes, alterations, refactors, updates
-	const int revision = 47;
+	const int revision = 48;
 
 	const std::string version_string = std::to_string(major) + "." + std::to_string(minor) + "." + std::to_string(revision);