Torque3D/Templates/Full/game/shaders/common/lighting.hlsl
2018-11-28 17:51:52 +10:00

237 lines
8.7 KiB
HLSL

//-----------------------------------------------------------------------------
// Copyright (c) 2012 GarageGames, LLC
// Portions Copyright Zefiros
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to
// deal in the Software without restriction, including without limitation the
// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
// sell copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
// IN THE SOFTWARE.
//-----------------------------------------------------------------------------
#include "./torque.hlsl"
#include "./brdf.hlsl"
#include "./shaderModelAutoGen.hlsl"
#ifndef TORQUE_SHADERGEN
// These are the uniforms used by most lighting shaders.
uniform float4 inLightPos[3];
uniform float4 inLightInvRadiusSq;
uniform float4 inLightColor[4];
#ifndef TORQUE_BL_NOSPOTLIGHT
uniform float4 inLightSpotDir[3];
uniform float4 inLightSpotAngle;
uniform float4 inLightSpotFalloff;
#endif
uniform float4 ambient;
uniform float smoothness;
uniform float metalness;
uniform float4 albedo;
#endif // !TORQUE_SHADERGEN
inline float3 getDistanceVectorToPlane( float3 origin, float3 direction, float4 plane )
{
float denum = dot( plane.xyz, direction.xyz );
float num = dot( plane, float4( origin, 1.0 ) );
float t = -num / denum;
return direction.xyz * t;
}
inline float3 getDistanceVectorToPlane( float negFarPlaneDotEye, float3 direction, float4 plane )
{
float denum = dot( plane.xyz, direction.xyz );
float t = negFarPlaneDotEye / denum;
return direction.xyz * t;
}
//TODO fix compute 4 lights
void compute4Lights( float3 wsView,
float3 wsPosition,
float3 wsNormal,
float4 shadowMask,
#ifdef TORQUE_SHADERGEN
float4 inLightPos[3],
float4 inLightInvRadiusSq,
float4 inLightColor[4],
float4 inLightSpotDir[3],
float4 inLightSpotAngle,
float4 inLightSpotFalloff,
float smoothness,
float metalness,
float4 albedo,
#endif // TORQUE_SHADERGEN
out float4 outDiffuse,
out float4 outSpecular )
{
outDiffuse = float4(0,0,0,0);
outSpecular = float4(0,0,0,0);
}
struct Surface
{
float3 P; // world space position
float3 N; // world space normal
float3 V; // world space view vector
float4 baseColor; // base color [0 -> 1] (rgba)
float metalness; // metalness [0:dielectric -> 1:metal]
float roughness; // roughness: [0:smooth -> 1:rough] (linear)
float roughness_brdf; // roughness remapped from linear to BRDF
float depth; // depth: [0:near -> 1:far] (linear)
float ao; // ambient occlusion [0 -> 1]
float matFlag; // material flag - use getFlag to retreive
float NdotV; // cos(angle between normal and view vector)
float3 f0; // fresnel value (rgb)
float3 albedo; // diffuse light absorbtion value (rgb)
float3 R; // reflection vector
float3 F; // fresnel term computed from f0, N and V
inline void Update()
{
NdotV = abs(dot(N, V)) + 1e-5f; // avoid artifact
albedo = baseColor.rgb * (1.0 - metalness);
f0 = lerp(0.04.xxx, baseColor.rgb, metalness);
R = -reflect(V, N);
float f90 = saturate(50.0 * dot(f0, 0.33));
F = F_Schlick(f0, f90, NdotV);
}
};
inline Surface createSurface(float4 gbuffer0, TORQUE_SAMPLER2D(gbufferTex1), TORQUE_SAMPLER2D(gbufferTex2), in float2 uv, in float3 wsEyePos, in float3 wsEyeRay, in float4x4 invView)
{
Surface surface = (Surface)0;
float4 gbuffer1 = TORQUE_TEX2DLOD(gbufferTex1, float4(uv,0,0));
float4 gbuffer2 = TORQUE_TEX2DLOD(gbufferTex2, float4(uv,0,0));
surface.depth = gbuffer0.a;
surface.P = wsEyePos + wsEyeRay * surface.depth;
surface.N = mul(invView, float4(gbuffer0.xyz,0)).xyz; //TODO move t3d to use WS normals
surface.V = normalize(wsEyePos - surface.P);
surface.baseColor = gbuffer1;
const float minRoughness=1e-4;
surface.roughness = clamp(1.0 - gbuffer2.b, minRoughness, 1.0); //t3d uses smoothness, so we convert to roughness.
surface.roughness_brdf = surface.roughness * surface.roughness;
surface.metalness = gbuffer2.a;
surface.ao = gbuffer2.g;
surface.matFlag = gbuffer2.r;
surface.Update();
return surface;
}
struct SurfaceToLight
{
float3 L; // surface to light vector
float3 Lu; // un-normalized surface to light vector
float3 H; // half-vector between view vector and light vector
float NdotL; // cos(angle between N and L)
float HdotV; // cos(angle between H and V) = HdotL = cos(angle between H and L)
float NdotH; // cos(angle between N and H)
};
inline SurfaceToLight createSurfaceToLight(in Surface surface, in float3 L)
{
SurfaceToLight surfaceToLight = (SurfaceToLight)0;
surfaceToLight.Lu = L;
surfaceToLight.L = normalize(L);
surfaceToLight.H = normalize(surface.V + surfaceToLight.L);
surfaceToLight.NdotL = saturate(dot(surfaceToLight.L, surface.N));
surfaceToLight.HdotV = saturate(dot(surfaceToLight.H, surface.V));
surfaceToLight.NdotH = saturate(dot(surfaceToLight.H, surface.N));
return surfaceToLight;
}
float3 BRDF_GetSpecular(in Surface surface, in SurfaceToLight surfaceToLight)
{
float f90 = saturate(50.0 * dot(surface.f0, 0.33));
float3 F = F_Schlick(surface.f0, f90, surfaceToLight.HdotV);
float Vis = V_SmithGGXCorrelated(surface.NdotV, surfaceToLight.NdotL, surface.roughness_brdf);
float D = D_GGX(surfaceToLight.NdotH, surface.roughness_brdf);
float3 Fr = D * F * Vis / M_PI_F;
return Fr;
}
float3 BRDF_GetDiffuse(in Surface surface, in SurfaceToLight surfaceToLight)
{
//getting some banding with disney method, using lambert instead - todo futher testing
float Fd = 1.0 / M_PI_F;
//energy conservation - remove this if reverting back to disney method
float3 kD = 1.0.xxx - surface.F;
kD *= 1.0 - surface.metalness;
float3 diffuse = kD * surface.baseColor.rgb * Fd;
return diffuse;
}
//attenuations functions from "moving frostbite to pbr paper"
//https://seblagarde.files.wordpress.com/2015/07/course_notes_moving_frostbite_to_pbr_v32.pdf
float smoothDistanceAtt ( float squaredDistance , float invSqrAttRadius )
{
float factor = squaredDistance * invSqrAttRadius ;
float smoothFactor = saturate (1.0f - factor * factor );
return sqr(smoothFactor);
}
float getDistanceAtt( float3 unormalizedLightVector , float invSqrAttRadius )
{
float sqrDist = dot ( unormalizedLightVector , unormalizedLightVector );
float attenuation = 1.0 / (max ( sqrDist , 0.01*0.01) );
attenuation *= smoothDistanceAtt ( sqrDist , invSqrAttRadius );
return attenuation;
}
float getSpotAngleAtt( float3 normalizedLightVector , float3 lightDir , float2 lightSpotParams )
{
float cd = dot ( lightDir , normalizedLightVector );
float attenuation = saturate ( ( cd - lightSpotParams.x ) / lightSpotParams.y );
// smooth the transition
return sqr(attenuation);
}
inline float3 getDirectionalLight(in Surface surface, in SurfaceToLight surfaceToLight, float3 lightColor, float lightIntensity, float shadow)
{
float3 factor = lightColor * max(surfaceToLight.NdotL, 0) * shadow * lightIntensity;
float3 diffuse = BRDF_GetDiffuse(surface,surfaceToLight) * factor;
float3 spec = BRDF_GetSpecular(surface,surfaceToLight) * factor;
float3 final = max(0.0f, diffuse + spec * surface.ao);
return final;
}
inline float3 getPunctualLight(in Surface surface, in SurfaceToLight surfaceToLight, float3 lightColor, float lightIntensity, float radius, float shadow)
{
float attenuation = getDistanceAtt(surfaceToLight.Lu, radius);
float3 factor = lightColor * max(surfaceToLight.NdotL, 0) * shadow * lightIntensity * attenuation;
float3 diffuse = BRDF_GetDiffuse(surface,surfaceToLight) * factor;
float3 spec = BRDF_GetSpecular(surface,surfaceToLight) * factor;
float3 final = max(0.0f, diffuse + spec * surface.ao * surface.F);
return final;
}