diff --git a/Effects/PBREffect.cs b/Effects/PBREffect.cs
index 4472bd7..ba73003 100644
--- a/Effects/PBREffect.cs
+++ b/Effects/PBREffect.cs
@@ -5,48 +5,81 @@ namespace Smuggler
{
public struct PBRLight
{
- public Vector3 direction;
- public Vector3 colour;
+ public Vector3 position;
+ public Vector3 color;
- public PBRLight(Vector3 direction, Vector3 colour)
+ public PBRLight(Vector3 position, Vector3 colour)
{
- this.direction = direction;
- this.colour = colour;
+ this.position = position;
+ this.color = colour;
+ }
+ }
+
+ public class PBRLightCollection
+ {
+ private readonly Vector3[] positions = new Vector3[4];
+ private readonly Vector3[] colors = new Vector3[4];
+
+ readonly EffectParameter lightPositionsParam;
+ readonly EffectParameter lightColorsParam;
+
+ public PBRLightCollection(EffectParameter lightPositionsParam, EffectParameter lightColorsParam)
+ {
+ this.lightPositionsParam = lightPositionsParam;
+ this.lightColorsParam = lightColorsParam;
+ }
+
+ public PBRLight this[int i]
+ {
+ get { return new PBRLight(positions[i], colors[i]); }
+ set
+ {
+ positions[i] = value.position;
+ colors[i] = value.color;
+ lightPositionsParam.SetValue(positions);
+ lightColorsParam.SetValue(colors);
+ }
}
}
public class PBREffect : Effect
{
- readonly EffectParameter modelParam;
- readonly EffectParameter viewParam;
- readonly EffectParameter projectionParam;
- readonly EffectParameter lightDirParam;
- readonly EffectParameter lightColourParam;
- readonly EffectParameter normalScaleParam;
- readonly EffectParameter emissiveFactorParam;
- readonly EffectParameter occlusionStrengthParam;
- readonly EffectParameter metallicRoughnessValuesParam;
- readonly EffectParameter baseColorFactorParam;
- readonly EffectParameter cameraLookParam;
+ EffectParameter worldParam;
+ EffectParameter viewParam;
+ EffectParameter projectionParam;
+ EffectParameter worldViewProjectionParam;
+ EffectParameter worldInverseTransposeParam;
- readonly EffectParameter baseColourTextureParam;
- readonly EffectParameter normalTextureParam;
- readonly EffectParameter emissionTextureParam;
- readonly EffectParameter occlusionTextureParam;
- readonly EffectParameter metallicRoughnessTextureParam;
- readonly EffectParameter envDiffuseTextureParam;
- readonly EffectParameter brdfLutTextureParam;
- readonly EffectParameter envSpecularTextureParam;
+ EffectParameter baseColorTextureParam;
+ EffectParameter normalTextureParam;
+ EffectParameter emissionTextureParam;
+ EffectParameter occlusionTextureParam;
+ EffectParameter metallicRoughnessTextureParam;
+ EffectParameter envDiffuseTextureParam;
+ EffectParameter brdfLutTextureParam;
+ EffectParameter envSpecularTextureParam;
+
+ EffectParameter lightPositionsParam;
+ EffectParameter lightColorsParam;
+
+ EffectParameter albedoParam;
+ EffectParameter metallicParam;
+ EffectParameter roughnessParam;
+ EffectParameter aoParam;
+
+ EffectParameter eyePositionParam;
Matrix world = Matrix.Identity;
Matrix view = Matrix.Identity;
Matrix projection = Matrix.Identity;
- PBRLight light = new PBRLight();
- float normalScale = 1;
- Vector3 emissiveFactor;
- float occlusionStrength;
- Vector2 metallicRoughnessValue;
- Vector4 baseColorFactor;
+ PBRLightCollection pbrLightCollection;
+
+ Vector3 albedo;
+ float metallic;
+ float roughness;
+ float ao;
+
+ // FIXME: lazily set properties for performance
public Matrix World
{
@@ -54,7 +87,9 @@ namespace Smuggler
set
{
world = value;
- modelParam.SetValue(world);
+ worldParam.SetValue(world);
+ worldViewProjectionParam.SetValue(world * view * projection);
+ worldInverseTransposeParam.SetValue(Matrix.Transpose(Matrix.Invert(world)));
}
}
@@ -65,11 +100,8 @@ namespace Smuggler
{
view = value;
viewParam.SetValue(view);
- cameraLookParam.SetValue(-new Vector3(
- view.M13,
- view.M23,
- view.M33
- ));
+ worldViewProjectionParam.SetValue(world * view * projection);
+ eyePositionParam.SetValue(Matrix.Invert(view).Translation);
}
}
@@ -79,75 +111,61 @@ namespace Smuggler
set
{
projection = value;
- projectionParam.SetValue(value);
+ projectionParam.SetValue(projection);
+ worldViewProjectionParam.SetValue(world * view * projection);
}
}
- public PBRLight Light
+ public PBRLightCollection Lights
{
- get { return light; }
- set
- {
- light = value;
- lightDirParam.SetValue(light.direction);
- lightColourParam.SetValue(light.colour);
- }
+ get { return pbrLightCollection; }
+ internal set { pbrLightCollection = value; }
}
- public float NormalScale
+ public Vector3 Albedo
{
- get { return normalScale; }
+ get { return albedo; }
set
{
- normalScale = value;
- normalScaleParam.SetValue(normalScale);
+ albedo = value;
+ albedoParam.SetValue(albedo);
}
}
- public Vector3 EmissiveFactor
+ public float Metallic
{
- get { return emissiveFactor; }
- set
- {
- emissiveFactor = value;
- emissiveFactorParam.SetValue(emissiveFactor);
- }
- }
-
- public float OcclusionStrength
- {
- get { return occlusionStrength; }
+ get { return metallic; }
set
{
- occlusionStrength = value;
- occlusionStrengthParam.SetValue(occlusionStrength);
+ metallic = value;
+ metallicParam.SetValue(metallic);
}
}
- public Vector2 MetallicRoughnessValue
+ public float Roughness
{
- get { return metallicRoughnessValue; }
+ get { return roughness; }
set
{
- metallicRoughnessValue = value;
- metallicRoughnessValuesParam.SetValue(metallicRoughnessValue);
+ roughness = value;
+ roughnessParam.SetValue(roughness);
}
}
- public Vector4 BaseColorFactor
+ public float AO
{
- get { return baseColorFactor; }
+ get { return ao; }
set
{
- baseColorFactor = value;
- baseColorFactorParam.SetValue(baseColorFactor);
+ ao = value;
+ aoParam.SetValue(ao);
}
}
public Texture2D BaseColourTexture
{
- get { return baseColourTextureParam.GetValueTexture2D(); }
- set { baseColourTextureParam.SetValue(value); }
+ get { return baseColorTextureParam.GetValueTexture2D(); }
+ set { baseColorTextureParam.SetValue(value); }
}
public Texture2D NormalTexture
@@ -194,66 +212,31 @@ namespace Smuggler
public PBREffect(GraphicsDevice graphicsDevice) : base(graphicsDevice, Resources.PBREffect)
{
- modelParam = Parameters["model"];
- viewParam = Parameters["view"];
- projectionParam = Parameters["projection"];
+ CacheEffectParameters(null);
- lightDirParam = Parameters["lightDir"];
- lightColourParam = Parameters["lightColour"];
-
- normalScaleParam = Parameters["normalScale"];
- emissiveFactorParam = Parameters["emissiveFactor"];
- occlusionStrengthParam = Parameters["occlusionStrength"];
- metallicRoughnessValuesParam = Parameters["metallicRoughnessValues"];
- baseColorFactorParam = Parameters["baseColorFactor"];
- cameraLookParam = Parameters["camera"];
-
- baseColourTextureParam = Parameters["baseColourTexture"];
- normalTextureParam = Parameters["normalTexture"];
- emissionTextureParam = Parameters["emissionTexture"];
- occlusionTextureParam = Parameters["occlusionTexture"];
- metallicRoughnessTextureParam = Parameters["metallicRoughnessTexture"];
- envDiffuseTextureParam = Parameters["envDiffuseTexture"];
- brdfLutTextureParam = Parameters["brdfLutTexture"];
- envSpecularTextureParam = Parameters["envSpecularTexture"];
+ pbrLightCollection = new PBRLightCollection(
+ Parameters["LightPositions"],
+ Parameters["LightColors"]
+ );
}
protected PBREffect(PBREffect cloneSource) : base(cloneSource)
{
- modelParam = Parameters["model"];
- viewParam = Parameters["view"];
- projectionParam = Parameters["param"];
-
- lightDirParam = Parameters["lightDir"];
- lightColourParam = Parameters["lightColour"];
-
- normalScaleParam = Parameters["normalScale"];
- emissiveFactorParam = Parameters["emissiveFactor"];
- occlusionStrengthParam = Parameters["occlusionStrength"];
- metallicRoughnessValuesParam = Parameters["metallicRoughnessValues"];
- baseColorFactorParam = Parameters["baseColorFactor"];
- cameraLookParam = Parameters["camera"];
-
- baseColourTextureParam = Parameters["baseColourTexture"];
- normalTextureParam = Parameters["normalTexture"];
- emissionTextureParam = Parameters["emissionTexture"];
- occlusionTextureParam = Parameters["occlusionTexture"];
- metallicRoughnessTextureParam = Parameters["metallicRoughnessTexture"];
- envDiffuseTextureParam = Parameters["envDiffuseTexture"];
- brdfLutTextureParam = Parameters["brdfLutTexture"];
- envSpecularTextureParam = Parameters["envSpecularTexture"];
+ CacheEffectParameters(cloneSource);
World = cloneSource.World;
View = cloneSource.View;
Projection = cloneSource.Projection;
- Light = cloneSource.Light;
+ Lights = new PBRLightCollection(
+ Parameters["LightPositions"],
+ Parameters["LightColors"]
+ );
- NormalScale = cloneSource.normalScale;
- EmissiveFactor = cloneSource.EmissiveFactor;
- OcclusionStrength = cloneSource.OcclusionStrength;
- MetallicRoughnessValue = cloneSource.MetallicRoughnessValue;
- BaseColorFactor = cloneSource.BaseColorFactor;
+ for (int i = 0; i < 4; i++)
+ {
+ Lights[i] = cloneSource.Lights[i];
+ }
BaseColourTexture = cloneSource.BaseColourTexture;
NormalTexture = cloneSource.NormalTexture;
@@ -263,6 +246,11 @@ namespace Smuggler
EnvDiffuseTexture = cloneSource.EnvDiffuseTexture;
BRDFLutTexture = cloneSource.BRDFLutTexture;
EnvSpecularTexture = cloneSource.EnvSpecularTexture;
+
+ Albedo = cloneSource.Albedo;
+ Metallic = cloneSource.Metallic;
+ Roughness = cloneSource.Roughness;
+ AO = cloneSource.AO;
}
public override Effect Clone()
@@ -275,5 +263,33 @@ namespace Smuggler
{
base.OnApply();
}
+
+ void CacheEffectParameters(PBREffect cloneSource)
+ {
+ worldParam = Parameters["World"];
+ viewParam = Parameters["View"];
+ projectionParam = Parameters["Projection"];
+ worldViewProjectionParam = Parameters["WorldViewProjection"];
+ worldInverseTransposeParam = Parameters["WorldInverseTranspose"];
+
+ baseColorTextureParam = Parameters["BaseColorTexture"];
+ normalTextureParam = Parameters["NormalTexture"];
+ emissionTextureParam = Parameters["EmissionTexture"];
+ occlusionTextureParam = Parameters["OcclusionTexture"];
+ metallicRoughnessTextureParam = Parameters["MetallicRoughnessTexture"];
+ envDiffuseTextureParam = Parameters["EnvDiffuseTexture"];
+ brdfLutTextureParam = Parameters["BrdfLutTexture"];
+ envSpecularTextureParam = Parameters["EnvSpecularTexture"];
+
+ lightPositionsParam = Parameters["LightPositions"];
+ lightColorsParam = Parameters["LightColors"];
+
+ albedoParam = Parameters["Albedo"];
+ metallicParam = Parameters["Metallic"];
+ roughnessParam = Parameters["Roughness"];
+ aoParam = Parameters["AO"];
+
+ eyePositionParam = Parameters["EyePosition"];
+ }
}
}
diff --git a/Effects/PBREffect.fx b/Effects/PBREffect.fx
index 9d49a36..e26bd49 100644
--- a/Effects/PBREffect.fx
+++ b/Effects/PBREffect.fx
@@ -1,408 +1,159 @@
+#include "Macros.fxh" //from FNA
-#include "Macros.fxh"
+static const float PI = 3.141592653589793;
-#define NORMALS
-#define UV
+// Transformation Matrices
-// A constant buffer that stores the three basic column-major matrices for composing geometry.
-cbuffer ModelViewProjectionConstantBuffer : register(b0)
-{
- matrix model;
- matrix view;
- matrix projection;
-};
+float4x4 World;
+float4x4 View;
+float4x4 Projection;
+
+float4x4 WorldViewProjection;
+float4x3 WorldInverseTranspose;
+
+// Samplers
+
+DECLARE_TEXTURE(BaseColorTexture, 0);
+DECLARE_TEXTURE(NormalTexture, 1);
+DECLARE_TEXTURE(EmissionTexture, 2);
+DECLARE_TEXTURE(OcclusionTexture, 3);
+DECLARE_TEXTURE(MetallicRoughnessTexture, 4);
+DECLARE_CUBEMAP(EnvDiffuseTexture, 8);
+DECLARE_TEXTURE(BrdfLutTexture, 9);
+DECLARE_CUBEMAP(EnvSpecularTexture, 10);
+
+// Light Info
+float3 LightPositions[4];
+float3 LightColors[4];
+
+// PBR Values
+float3 Albedo;
+float Metallic;
+float Roughness;
+float AO;
+
+float3 EyePosition;
-// Per-vertex data used as input to the vertex shader.
struct VertexShaderInput
{
- float4 position : POSITION;
-#ifdef NORMALS
- float3 normal : NORMAL;
-#endif
-#ifdef UV
- float2 texcoord : TEXCOORD0;
-#endif
+ float4 Position : POSITION;
+ float3 Normal : NORMAL;
+ float2 TexCoord : TEXCOORD0;
};
-// Per-pixel color data passed through the pixel shader.
struct PixelShaderInput
{
- float4 position : SV_POSITION;
- float3 poswithoutw : POSITION1;
-
-#ifdef NORMALS
- float3 normal : NORMAL;
-#endif
-
- float2 texcoord : TEXCOORD0;
+ float4 Position : SV_POSITION;
+ float2 TexCoord : TEXCOORD0;
+ float3 PositionWS : TEXCOORD1;
+ float3 NormalWS : TEXCOORD2;
};
PixelShaderInput main_vs(VertexShaderInput input)
{
PixelShaderInput output;
- // Transform the vertex position into projected space.
- float4 pos = mul(input.position, model);
- output.poswithoutw = float3(pos.xyz) / pos.w;
-
-#ifdef NORMALS
- // If we have normals...
- output.normal = normalize(mul(float4(input.normal.xyz, 0.0), model));
-#endif
-
-#ifdef UV
- output.texcoord = input.texcoord;
-#else
- output.texcoord = float2(0.0f, 0.0f);
-#endif
-
-#ifdef HAS_NORMALS
-#ifdef HAS_TANGENTS
- vec3 normalW = normalize(vec3(u_ModelMatrix * vec4(a_Normal.xyz, 0.0)));
- vec3 tangentW = normalize(vec3(u_ModelMatrix * vec4(a_Tangent.xyz, 0.0)));
- vec3 bitangentW = cross(normalW, tangentW) * a_Tangent.w;
- v_TBN = mat3(tangentW, bitangentW, normalW);
-#else // HAS_TANGENTS != 1
- v_Normal = normalize(vec3(u_ModelMatrix * vec4(a_Normal.xyz, 0.0)));
-#endif
-#endif
-
- // Transform the vertex position into projected space.
- pos = mul(pos, view);
- pos = mul(pos, projection);
- output.position = pos;
+ output.PositionWS = mul(input.Position, World).xyz;
+ output.TexCoord = input.TexCoord;
+ output.NormalWS = normalize(mul(WorldInverseTranspose, input.Normal));
+ output.Position = mul(input.Position, WorldViewProjection);
return output;
}
-//
-// This fragment shader defines a reference implementation for Physically Based Shading of
-// a microfacet surface material defined by a glTF model.
-//
-// References:
-// [1] Real Shading in Unreal Engine 4
-// http://blog.selfshadow.com/publications/s2013-shading-course/karis/s2013_pbs_epic_notes_v2.pdf
-// [2] Physically Based Shading at Disney
-// http://blog.selfshadow.com/publications/s2012-shading-course/burley/s2012_pbs_disney_brdf_notes_v3.pdf
-// [3] README.md - Environment Maps
-// https://github.com/KhronosGroup/glTF-WebGL-PBR/#environment-maps
-// [4] "An Inexpensive BRDF Model for Physically based Rendering" by Christophe Schlick
-// https://www.cs.virginia.edu/~jdl/bib/appearance/analytic%20models/schlick94b.pdf
-
-#define NORMALS
-#define UV
-#define HAS_NORMALS
-// #define USE_IBL
-#define USE_TEX_LOD
-
-DECLARE_TEXTURE(baseColourTexture, 0);
-DECLARE_TEXTURE(normalTexture, 1);
-DECLARE_TEXTURE(emissionTexture, 2);
-DECLARE_TEXTURE(occlusionTexture, 3);
-DECLARE_TEXTURE(metallicRoughnessTexture, 4);
-DECLARE_CUBEMAP(envDiffuseTexture, 8);
-DECLARE_TEXTURE(brdfLutTexture, 9);
-DECLARE_CUBEMAP(envSpecularTexture, 10);
-
-cbuffer cbPerFrame : register(b0)
+float3 FresnelSchlick(float cosTheta, float3 F0)
{
- float3 lightDir;
- float3 lightColour;
-};
-
-cbuffer cbPerObject : register(b1)
-{
- float normalScale;
- float3 emissiveFactor;
- float occlusionStrength;
- float2 metallicRoughnessValues;
- float4 baseColorFactor;
- float3 camera;
-
- // debugging flags used for shader output of intermediate PBR variables
- float4 scaleDiffBaseMR;
- float4 scaleFGDSpec;
- float4 scaleIBLAmbient;
-};
-
-#ifdef HAS_NORMALS
-#ifdef HAS_TANGENTS
-varying mat3 v_TBN;
-#else
-#endif
-#endif
-
-// Encapsulate the various inputs used by the various functions in the shading equation
-// We store values in this struct to simplify the integration of alternative implementations
-// of the shading terms, outlined in the Readme.MD Appendix.
-struct PBRInfo
-{
- float NdotL; // cos angle between normal and light direction
- float NdotV; // cos angle between normal and view direction
- float NdotH; // cos angle between normal and half vector
- float LdotH; // cos angle between light direction and half vector
- float VdotH; // cos angle between view direction and half vector
- float perceptualRoughness; // roughness value, as authored by the model creator (input to shader)
- float metalness; // metallic value at the surface
- float3 reflectance0; // full reflectance color (normal incidence angle)
- float3 reflectance90; // reflectance color at grazing angle
- float alphaRoughness; // roughness mapped to a more linear change in the roughness (proposed by [2])
- float3 diffuseColor; // color contribution from diffuse lighting
- float3 specularColor; // color contribution from specular lighting
-};
-
-static const float M_PI = 3.141592653589793;
-static const float c_MinRoughness = 0.04;
-
-float4 SRGBtoLINEAR(float4 srgbIn)
-{
-#ifdef MANUAL_SRGB
-#ifdef SRGB_FAST_APPROXIMATION
- float3 linOut = pow(srgbIn.xyz,float3(2.2, 2.2, 2.2));
-#else //SRGB_FAST_APPROXIMATION
- float3 bLess = step(float3(0.04045, 0.04045, 0.04045), srgbIn.xyz);
- float3 linOut = lerp(srgbIn.xyz / float3(12.92, 12.92, 12.92), pow((srgbIn.xyz + float3(0.055, 0.055, 0.055)) / float3(1.055, 1.055, 1.055), float3(2.4, 2.4, 2.4)), bLess);
-#endif //SRGB_FAST_APPROXIMATION
- return float4(linOut,srgbIn.w);;
-#else //MANUAL_SRGB
- return srgbIn;
-#endif //MANUAL_SRGB
+ return F0 + (1.0 - F0) * pow(1.0 - cosTheta, 5.0);
}
-// Find the normal for this fragment, pulling either from a predefined normal map
-// or from the interpolated mesh normal and tangent attributes.
-float3 getNormal(float3 position, float3 normal, float2 uv)
+float DistributionGGX(float3 N, float3 H, float roughness)
{
- // Retrieve the tangent space matrix
-#ifndef HAS_TANGENTS
- float3 pos_dx = ddx(position);
- float3 pos_dy = ddy(position);
- float3 tex_dx = ddx(float3(uv, 0.0));
- float3 tex_dy = ddy(float3(uv, 0.0));
- float3 t = (tex_dy.y * pos_dx - tex_dx.y * pos_dy) / (tex_dx.x * tex_dy.y - tex_dy.x * tex_dx.y);
+ float a = roughness * roughness;
+ float a2 = a * a;
+ float NdotH = max(dot(N, H), 0.0);
+ float NdotH2 = NdotH * NdotH;
-#ifdef HAS_NORMALS
- float3 ng = normalize(normal);
-#else
- float3 ng = cross(pos_dx, pos_dy);
-#endif
+ float num = a2;
+ float denom = (NdotH2 * (a2 - 1.0) + 1.0);
+ denom = PI * denom * denom;
- t = normalize(t - ng * dot(ng, t));
- float3 b = normalize(cross(ng, t));
- row_major float3x3 tbn = float3x3(t, b, ng);
-
-#else // HAS_TANGENTS
- mat3 tbn = v_TBN;
-#endif
-
-#ifdef HAS_NORMALMAP
- float3 n = SAMPLE_TEXTURE(normalTexture, uv).rgb;
-
- // Need to check the multiplication is equivalent..
- n = normalize(mul(((2.0 * n - 1.0) * float3(normalScale, normalScale, 1.0)), tbn));
-#else
- float3 n = tbn[2].xyz;
-#endif
-
- return n;
+ return num / denom;
}
-#ifdef USE_IBL
-// Calculation of the lighting contribution from an optional Image Based Light source.
-// Precomputed Environment Maps are required uniform inputs and are computed as outlined in [1].
-// See our README.md on Environment Maps [3] for additional discussion.
-float3 getIBLContribution(PBRInfo pbrInputs, float3 n, float3 reflection)
+float GeometrySchlickGGX(float NdotV, float roughness)
{
- float mipCount = 9.0; // resolution of 512x512
- float lod = (pbrInputs.perceptualRoughness * mipCount);
-
- // retrieve a scale and bias to F0. See [1], Figure 3
- float2 val = float2(pbrInputs.NdotV, 1.0 - pbrInputs.perceptualRoughness);
- float3 brdf = SRGBtoLINEAR(SAMPLE_TEXTURE(brdfLutTexture, val)).rgb;
+ float r = (roughness + 1.0);
+ float k = (r * r) / 8.0;
- float3 diffuseLight = SRGBtoLINEAR(SAMPLE_CUBEMAP(envDiffuseTexture, n)).rgb;
+ float num = NdotV;
+ float denom = NdotV * (1.0 - k) + k;
-#ifdef USE_TEX_LOD
- float4 reflectionWithLOD = float4(reflection, 0);
- float3 specularLight = SRGBtoLINEAR(SAMPLE_CUBEMAP_LOD(envSpecularTexture, reflectionWithLOD)).rgb;
-#else
- float3 specularLight = SRGBtoLINEAR(SAMPLE_CUBEMAP(envSpecularTexture, reflection)).rgb;
-#endif
-
- float3 diffuse = diffuseLight * pbrInputs.diffuseColor;
- float3 specular = specularLight * (pbrInputs.specularColor * brdf.x + brdf.y);
-
- // For presentation, this allows us to disable IBL terms
- diffuse *= scaleIBLAmbient.x;
- specular *= scaleIBLAmbient.y;
-
- return diffuse + specular;
-}
-#endif
-
-// Basic Lambertian diffuse
-// Implementation from Lambert's Photometria https://archive.org/details/lambertsphotome00lambgoog
-// See also [1], Equation 1
-float3 diffuse(PBRInfo pbrInputs)
-{
- return pbrInputs.diffuseColor / M_PI;
+ return num / denom;
}
-// The following equation models the Fresnel reflectance term of the spec equation (aka F())
-// Implementation of fresnel from [4], Equation 15
-float3 specularReflection(PBRInfo pbrInputs)
+float GeometrySmith(float3 N, float3 V, float3 L, float roughness)
{
- return pbrInputs.reflectance0 + (pbrInputs.reflectance90 - pbrInputs.reflectance0) * pow(clamp(1.0 - pbrInputs.VdotH, 0.0, 1.0), 5.0);
+ float NdotV = max(dot(N, V), 0.0);
+ float NdotL = max(dot(N, L), 0.0);
+ float ggx2 = GeometrySchlickGGX(NdotV, roughness);
+ float ggx1 = GeometrySchlickGGX(NdotL, roughness);
+
+ return ggx1 * ggx2;
}
-// This calculates the specular geometric attenuation (aka G()),
-// where rougher material will reflect less light back to the viewer.
-// This implementation is based on [1] Equation 4, and we adopt their modifications to
-// alphaRoughness as input as originally proposed in [2].
-float geometricOcclusion(PBRInfo pbrInputs)
+// The case where we have no texture maps for any PBR data
+float4 None(PixelShaderInput input) : SV_TARGET
{
- float NdotL = pbrInputs.NdotL;
- float NdotV = pbrInputs.NdotV;
- float r = pbrInputs.alphaRoughness;
+ float3 N = normalize(input.NormalWS);
+ float3 V = normalize(EyePosition - input.PositionWS);
- float attenuationL = 2.0 * NdotL / (NdotL + sqrt(r * r + (1.0 - r * r) * (NdotL * NdotL)));
- float attenuationV = 2.0 * NdotV / (NdotV + sqrt(r * r + (1.0 - r * r) * (NdotV * NdotV)));
- return attenuationL * attenuationV;
-}
+ float3 Lo = float3(0.0, 0.0, 0.0);
-// The following equation(s) model the distribution of microfacet normals across the area being drawn (aka D())
-// Implementation from "Average Irregularity Representation of a Roughened Surface for Ray Reflection" by T. S. Trowbridge, and K. P. Reitz
-// Follows the distribution function recommended in the SIGGRAPH 2013 course notes from EPIC Games [1], Equation 3.
-float microfacetDistribution(PBRInfo pbrInputs)
-{
- float roughnessSq = pbrInputs.alphaRoughness * pbrInputs.alphaRoughness;
- float f = (pbrInputs.NdotH * roughnessSq - pbrInputs.NdotH) * pbrInputs.NdotH + 1.0;
- return roughnessSq / (M_PI * f * f);
-}
+ for (int i = 0; i < 4; i++)
+ {
+ float3 lightDir = LightPositions[i] - input.PositionWS;
+ float3 L = normalize(lightDir);
+ float3 H = normalize(V + L);
-float4 main_ps(PixelShaderInput input) : SV_TARGET
-{
- // Metallic and Roughness material properties are packed together
- // In glTF, these factors can be specified by fixed scalar values
- // or from a metallic-roughness map
- float perceptualRoughness = metallicRoughnessValues.y;
- float metallic = metallicRoughnessValues.x;
+ float distance = length(lightDir);
+ float attenuation = 1.0 / (distance * distance);
+ float3 radiance = LightColors[i] * attenuation;
-#ifdef HAS_METALROUGHNESSMAP
- // Roughness is stored in the 'g' channel, metallic is stored in the 'b' channel.
- // This layout intentionally reserves the 'r' channel for (optional) occlusion map data
- float4 mrSample = SAMPLE_TEXTURE(metallicRoughnessTexture, input.texcoord);
+ float3 F0 = float3(0.04, 0.04, 0.04);
+ F0 = lerp(F0, Albedo, Metallic);
+ float3 F = FresnelSchlick(max(dot(H, V), 0.0), F0);
- // Had to reverse the order of the channels here - TODO: investigate..
- perceptualRoughness = mrSample.g * perceptualRoughness;
- metallic = mrSample.b * metallic;
-#endif
+ float NDF = DistributionGGX(N, H, Roughness);
+ float G = GeometrySmith(N, V, L, Roughness);
- perceptualRoughness = clamp(perceptualRoughness, c_MinRoughness, 1.0);
- metallic = clamp(metallic, 0.0, 1.0);
+ float3 numerator = NDF * G * F;
+ float denominator = 4.0 * max(dot(N, V), 0.0) * max(dot(N, L), 0.0);
+ float3 specular = numerator / max(denominator, 0.001);
- // Roughness is authored as perceptual roughness; as is convention,
- // convert to material roughness by squaring the perceptual roughness [2].
- float alphaRoughness = perceptualRoughness * perceptualRoughness;
+ float3 kS = F;
+ float3 kD = float3(1.0, 1.0, 1.0) - kS;
- // The albedo may be defined from a base texture or a flat color
+ kD *= 1.0 - Metallic;
-#ifdef HAS_BASECOLORMAP
- float4 baseColor = SRGBtoLINEAR(SAMPLE_TEXTURE(baseColourTexture, input.texcoord)) * baseColorFactor;
-#else
- float4 baseColor = baseColorFactor;
-#endif
+ float NdotL = max(dot(N, L), 0.0);
+ Lo += (kD * Albedo / PI + specular) * radiance * NdotL;
+ }
- float3 f0 = float3(0.04, 0.04, 0.04);
- float3 diffuseColor = baseColor.rgb * (float3(1.0, 1.0, 1.0) - f0);
+ float3 ambient = float3(0.03, 0.03, 0.03) * Albedo * AO;
+ float3 color = ambient + Lo;
- diffuseColor *= 1.0 - metallic;
-
- float3 specularColor = lerp(f0, baseColor.rgb, metallic);
-
- // Compute reflectance.
- float reflectance = max(max(specularColor.r, specularColor.g), specularColor.b);
-
- // For typical incident reflectance range (between 4% to 100%) set the grazing reflectance to 100% for typical fresnel effect.
- // For very low reflectance range on highly diffuse objects (below 4%), incrementally reduce grazing reflecance to 0%.
- float reflectance90 = clamp(reflectance * 25.0, 0.0, 1.0);
- float3 specularEnvironmentR0 = specularColor.rgb;
- float3 specularEnvironmentR90 = float3(1.0, 1.0, 1.0) * reflectance90;
-
- float3 n = getNormal(input.poswithoutw, input.normal, input.texcoord); // normal at surface point
- float3 v = normalize(camera - input.poswithoutw); // Vector from surface point to camera
-
- float3 l = normalize(lightDir); // Vector from surface point to light
- float3 h = normalize(l + v); // Half vector between both l and v
- float3 reflection = -normalize(reflect(v, n));
-
- float NdotL = clamp(dot(n, l), 0.001, 1.0);
- float NdotV = abs(dot(n, v)) + 0.001;
- float NdotH = clamp(dot(n, h), 0.0, 1.0);
- float LdotH = clamp(dot(l, h), 0.0, 1.0);
- float VdotH = clamp(dot(v, h), 0.0, 1.0);
-
- PBRInfo pbrInputs;
- pbrInputs.NdotL = NdotL;
- pbrInputs.NdotV = NdotV;
- pbrInputs.NdotH = NdotH;
- pbrInputs.LdotH = LdotH;
- pbrInputs.VdotH = VdotH;
- pbrInputs.perceptualRoughness = perceptualRoughness;
- pbrInputs.metalness = metallic;
- pbrInputs.reflectance0 = specularEnvironmentR0;
- pbrInputs.reflectance90 = specularEnvironmentR90;
- pbrInputs.alphaRoughness = alphaRoughness;
- pbrInputs.diffuseColor = diffuseColor;
- pbrInputs.specularColor = specularColor;
-
- // Calculate the shading terms for the microfacet specular shading model
- float3 F = specularReflection(pbrInputs);
-
- float G = geometricOcclusion(pbrInputs);
- float D = microfacetDistribution(pbrInputs);
-
- // Calculation of analytical lighting contribution
- float3 diffuseContrib = (1.0 - F) * diffuse(pbrInputs);
- float3 specContrib = F * G * D / (4.0 * NdotL * NdotV);
- float3 color = NdotL * lightColour * (diffuseContrib + specContrib);
-
-
- // Calculate lighting contribution from image based lighting source (IBL)
-#ifdef USE_IBL
- color += getIBLContribution(pbrInputs, n, reflection);
-#endif
-
- // Apply optional PBR terms for additional (optional) shading
-#ifdef HAS_OCCLUSIONMAP
- float ao = SAMPLE_TEXTURE(occlusionTexture, input.texcoord).r;
- color = lerp(color, color * ao, occlusionStrength);
-#endif
-
-#ifdef HAS_EMISSIVEMAP
- float3 emissive = SRGBtoLINEAR(SAMPLE_TEXTURE(emissionTexture, input.texcoord)).rgb * emissiveFactor;
- color += emissive;
-#endif
-
- // This section uses lerp to override final color for reference app visualization
- // of various parameters in the lighting equation.
- color = lerp(color, F, scaleFGDSpec.x);
- color = lerp(color, float3(G, G, G), scaleFGDSpec.y);
- color = lerp(color, float3(D, D, D), scaleFGDSpec.z);
- color = lerp(color, specContrib, scaleFGDSpec.w);
- color = lerp(color, diffuseContrib, scaleDiffBaseMR.x);
- color = lerp(color, baseColor.rgb, scaleDiffBaseMR.y);
- color = lerp(color, float3(metallic, metallic, metallic), scaleDiffBaseMR.z);
- color = lerp(color, float3(perceptualRoughness, perceptualRoughness, perceptualRoughness), scaleDiffBaseMR.w);
+ color = color / (color + float3(1.0, 1.0, 1.0));
+ float exposureConstant = 1.0 / 2.2;
+ color = pow(color, float3(exposureConstant, exposureConstant, exposureConstant));
return float4(color, 1.0);
}
Technique PBR
{
- Pass pass1
- {
- VertexShader = compile vs_3_0 main_vs();
- PixelShader = compile ps_3_0 main_ps();
- }
+ Pass Pass1
+ {
+ VertexShader = compile vs_3_0 main_vs();
+ PixelShader = compile ps_3_0 None();
+ }
}
diff --git a/Effects/PBREffect.fxb b/Effects/PBREffect.fxb
index c6d92be..bcc23fa 100644
Binary files a/Effects/PBREffect.fxb and b/Effects/PBREffect.fxb differ
diff --git a/Effects/ReferencePBREffect.fx b/Effects/ReferencePBREffect.fx
new file mode 100644
index 0000000..61609b9
--- /dev/null
+++ b/Effects/ReferencePBREffect.fx
@@ -0,0 +1,410 @@
+
+#include "Macros.fxh"
+
+#define NORMALS
+#define UV
+#define HAS_BASECOLORMAP
+
+// A constant buffer that stores the three basic column-major matrices for composing geometry.
+cbuffer ModelViewProjectionConstantBuffer : register(b0)
+{
+ matrix model;
+ matrix view;
+ matrix projection;
+};
+
+// Per-vertex data used as input to the vertex shader.
+struct VertexShaderInput
+{
+ float4 position : POSITION;
+#ifdef NORMALS
+ float3 normal : NORMAL;
+#endif
+#ifdef UV
+ float2 texcoord : TEXCOORD0;
+#endif
+};
+
+// Per-pixel color data passed through the pixel shader.
+struct PixelShaderInput
+{
+ float4 position : SV_POSITION;
+ float4 positionWS : TEXCOORD1;
+ float3 normalWS : TEXCOORD2;
+
+#ifdef NORMALS
+ float3 normal : NORMAL;
+#endif
+
+ float2 texcoord : TEXCOORD0;
+};
+
+PixelShaderInput main_vs(VertexShaderInput input)
+{
+ PixelShaderInput output;
+
+ // Transform the vertex position into projected space.
+ float4 pos = mul(input.position, model);
+
+#ifdef NORMALS
+ // If we have normals...
+ output.normal = normalize(mul(float4(input.normal.xyz, 0.0), model));
+#endif
+
+#ifdef UV
+ output.texcoord = input.texcoord;
+#else
+ output.texcoord = float2(0.0f, 0.0f);
+#endif
+
+#ifdef HAS_NORMALS
+#ifdef HAS_TANGENTS
+ vec3 normalW = normalize(vec3(u_ModelMatrix * vec4(a_Normal.xyz, 0.0)));
+ vec3 tangentW = normalize(vec3(u_ModelMatrix * vec4(a_Tangent.xyz, 0.0)));
+ vec3 bitangentW = cross(normalW, tangentW) * a_Tangent.w;
+ v_TBN = mat3(tangentW, bitangentW, normalW);
+#else // HAS_TANGENTS != 1
+ v_Normal = normalize(vec3(u_ModelMatrix * vec4(a_Normal.xyz, 0.0)));
+#endif
+#endif
+
+ // Transform the vertex position into projected space.
+ pos = mul(pos, view);
+ pos = mul(pos, projection);
+ output.position = pos;
+
+ return output;
+}
+
+//
+// This fragment shader defines a reference implementation for Physically Based Shading of
+// a microfacet surface material defined by a glTF model.
+//
+// References:
+// [1] Real Shading in Unreal Engine 4
+// http://blog.selfshadow.com/publications/s2013-shading-course/karis/s2013_pbs_epic_notes_v2.pdf
+// [2] Physically Based Shading at Disney
+// http://blog.selfshadow.com/publications/s2012-shading-course/burley/s2012_pbs_disney_brdf_notes_v3.pdf
+// [3] README.md - Environment Maps
+// https://github.com/KhronosGroup/glTF-WebGL-PBR/#environment-maps
+// [4] "An Inexpensive BRDF Model for Physically based Rendering" by Christophe Schlick
+// https://www.cs.virginia.edu/~jdl/bib/appearance/analytic%20models/schlick94b.pdf
+
+#define NORMALS
+#define UV
+#define HAS_NORMALS
+// #define USE_IBL
+#define USE_TEX_LOD
+
+DECLARE_TEXTURE(baseColourTexture, 0);
+DECLARE_TEXTURE(normalTexture, 1);
+DECLARE_TEXTURE(emissionTexture, 2);
+DECLARE_TEXTURE(occlusionTexture, 3);
+DECLARE_TEXTURE(metallicRoughnessTexture, 4);
+DECLARE_CUBEMAP(envDiffuseTexture, 8);
+DECLARE_TEXTURE(brdfLutTexture, 9);
+DECLARE_CUBEMAP(envSpecularTexture, 10);
+
+cbuffer cbPerFrame : register(b0)
+{
+ float3 lightDir;
+ float3 lightColour;
+};
+
+cbuffer cbPerObject : register(b1)
+{
+ float normalScale;
+ float3 emissiveFactor;
+ float occlusionStrength;
+ float2 metallicRoughnessValues;
+ float4 baseColorFactor;
+ float3 camera;
+
+ // debugging flags used for shader output of intermediate PBR variables
+ float4 scaleDiffBaseMR;
+ float4 scaleFGDSpec;
+ float4 scaleIBLAmbient;
+};
+
+#ifdef HAS_NORMALS
+#ifdef HAS_TANGENTS
+varying mat3 v_TBN;
+#else
+#endif
+#endif
+
+// Encapsulate the various inputs used by the various functions in the shading equation
+// We store values in this struct to simplify the integration of alternative implementations
+// of the shading terms, outlined in the Readme.MD Appendix.
+struct PBRInfo
+{
+ float NdotL; // cos angle between normal and light direction
+ float NdotV; // cos angle between normal and view direction
+ float NdotH; // cos angle between normal and half vector
+ float LdotH; // cos angle between light direction and half vector
+ float VdotH; // cos angle between view direction and half vector
+ float perceptualRoughness; // roughness value, as authored by the model creator (input to shader)
+ float metalness; // metallic value at the surface
+ float3 reflectance0; // full reflectance color (normal incidence angle)
+ float3 reflectance90; // reflectance color at grazing angle
+ float alphaRoughness; // roughness mapped to a more linear change in the roughness (proposed by [2])
+ float3 diffuseColor; // color contribution from diffuse lighting
+ float3 specularColor; // color contribution from specular lighting
+};
+
+static const float M_PI = 3.141592653589793;
+static const float c_MinRoughness = 0.04;
+
+float4 SRGBtoLINEAR(float4 srgbIn)
+{
+#ifdef MANUAL_SRGB
+#ifdef SRGB_FAST_APPROXIMATION
+ float3 linOut = pow(srgbIn.xyz,float3(2.2, 2.2, 2.2));
+#else //SRGB_FAST_APPROXIMATION
+ float3 bLess = step(float3(0.04045, 0.04045, 0.04045), srgbIn.xyz);
+ float3 linOut = lerp(srgbIn.xyz / float3(12.92, 12.92, 12.92), pow((srgbIn.xyz + float3(0.055, 0.055, 0.055)) / float3(1.055, 1.055, 1.055), float3(2.4, 2.4, 2.4)), bLess);
+#endif //SRGB_FAST_APPROXIMATION
+ return float4(linOut,srgbIn.w);;
+#else //MANUAL_SRGB
+ return srgbIn;
+#endif //MANUAL_SRGB
+}
+
+// Find the normal for this fragment, pulling either from a predefined normal map
+// or from the interpolated mesh normal and tangent attributes.
+float3 getNormal(float3 position, float3 normal, float2 uv)
+{
+ // Retrieve the tangent space matrix
+#ifndef HAS_TANGENTS
+ float3 pos_dx = ddx(position);
+ float3 pos_dy = ddy(position);
+ float3 tex_dx = ddx(float3(uv, 0.0));
+ float3 tex_dy = ddy(float3(uv, 0.0));
+ float3 t = (tex_dy.y * pos_dx - tex_dx.y * pos_dy) / (tex_dx.x * tex_dy.y - tex_dy.x * tex_dx.y);
+
+#ifdef HAS_NORMALS
+ float3 ng = normalize(normal);
+#else
+ float3 ng = cross(pos_dx, pos_dy);
+#endif
+
+ t = normalize(t - ng * dot(ng, t));
+ float3 b = normalize(cross(ng, t));
+ row_major float3x3 tbn = float3x3(t, b, ng);
+
+#else // HAS_TANGENTS
+ mat3 tbn = v_TBN;
+#endif
+
+#ifdef HAS_NORMALMAP
+ float3 n = SAMPLE_TEXTURE(normalTexture, uv).rgb;
+
+ // Need to check the multiplication is equivalent..
+ n = normalize(mul(((2.0 * n - 1.0) * float3(normalScale, normalScale, 1.0)), tbn));
+#else
+ float3 n = tbn[2].xyz;
+#endif
+
+ return n;
+}
+
+#ifdef USE_IBL
+// Calculation of the lighting contribution from an optional Image Based Light source.
+// Precomputed Environment Maps are required uniform inputs and are computed as outlined in [1].
+// See our README.md on Environment Maps [3] for additional discussion.
+float3 getIBLContribution(PBRInfo pbrInputs, float3 n, float3 reflection)
+{
+ float mipCount = 9.0; // resolution of 512x512
+ float lod = (pbrInputs.perceptualRoughness * mipCount);
+
+ // retrieve a scale and bias to F0. See [1], Figure 3
+ float2 val = float2(pbrInputs.NdotV, 1.0 - pbrInputs.perceptualRoughness);
+ float3 brdf = SRGBtoLINEAR(SAMPLE_TEXTURE(brdfLutTexture, val)).rgb;
+
+ float3 diffuseLight = SRGBtoLINEAR(SAMPLE_CUBEMAP(envDiffuseTexture, n)).rgb;
+
+#ifdef USE_TEX_LOD
+ float4 reflectionWithLOD = float4(reflection, 0);
+ float3 specularLight = SRGBtoLINEAR(SAMPLE_CUBEMAP_LOD(envSpecularTexture, reflectionWithLOD)).rgb;
+#else
+ float3 specularLight = SRGBtoLINEAR(SAMPLE_CUBEMAP(envSpecularTexture, reflection)).rgb;
+#endif
+
+ float3 diffuse = diffuseLight * pbrInputs.diffuseColor;
+ float3 specular = specularLight * (pbrInputs.specularColor * brdf.x + brdf.y);
+
+ // For presentation, this allows us to disable IBL terms
+ diffuse *= scaleIBLAmbient.x;
+ specular *= scaleIBLAmbient.y;
+
+ return diffuse + specular;
+}
+#endif
+
+// Basic Lambertian diffuse
+// Implementation from Lambert's Photometria https://archive.org/details/lambertsphotome00lambgoog
+// See also [1], Equation 1
+float3 diffuse(PBRInfo pbrInputs)
+{
+ return pbrInputs.diffuseColor / M_PI;
+}
+
+// The following equation models the Fresnel reflectance term of the spec equation (aka F())
+// Implementation of fresnel from [4], Equation 15
+float3 specularReflection(PBRInfo pbrInputs)
+{
+ return pbrInputs.reflectance0 + (pbrInputs.reflectance90 - pbrInputs.reflectance0) * pow(clamp(1.0 - pbrInputs.VdotH, 0.0, 1.0), 5.0);
+}
+
+// This calculates the specular geometric attenuation (aka G()),
+// where rougher material will reflect less light back to the viewer.
+// This implementation is based on [1] Equation 4, and we adopt their modifications to
+// alphaRoughness as input as originally proposed in [2].
+float geometricOcclusion(PBRInfo pbrInputs)
+{
+ float NdotL = pbrInputs.NdotL;
+ float NdotV = pbrInputs.NdotV;
+ float r = pbrInputs.alphaRoughness;
+
+ float attenuationL = 2.0 * NdotL / (NdotL + sqrt(r * r + (1.0 - r * r) * (NdotL * NdotL)));
+ float attenuationV = 2.0 * NdotV / (NdotV + sqrt(r * r + (1.0 - r * r) * (NdotV * NdotV)));
+ return attenuationL * attenuationV;
+}
+
+// The following equation(s) model the distribution of microfacet normals across the area being drawn (aka D())
+// Implementation from "Average Irregularity Representation of a Roughened Surface for Ray Reflection" by T. S. Trowbridge, and K. P. Reitz
+// Follows the distribution function recommended in the SIGGRAPH 2013 course notes from EPIC Games [1], Equation 3.
+float microfacetDistribution(PBRInfo pbrInputs)
+{
+ float roughnessSq = pbrInputs.alphaRoughness * pbrInputs.alphaRoughness;
+ float f = (pbrInputs.NdotH * roughnessSq - pbrInputs.NdotH) * pbrInputs.NdotH + 1.0;
+ return roughnessSq / (M_PI * f * f);
+}
+
+float4 main_ps(PixelShaderInput input) : SV_TARGET
+{
+ // Metallic and Roughness material properties are packed together
+ // In glTF, these factors can be specified by fixed scalar values
+ // or from a metallic-roughness map
+ float perceptualRoughness = metallicRoughnessValues.y;
+ float metallic = metallicRoughnessValues.x;
+
+#ifdef HAS_METALROUGHNESSMAP
+ // Roughness is stored in the 'g' channel, metallic is stored in the 'b' channel.
+ // This layout intentionally reserves the 'r' channel for (optional) occlusion map data
+ float4 mrSample = SAMPLE_TEXTURE(metallicRoughnessTexture, input.texcoord);
+
+ // Had to reverse the order of the channels here - TODO: investigate..
+ perceptualRoughness = mrSample.g * perceptualRoughness;
+ metallic = mrSample.b * metallic;
+#endif
+
+ perceptualRoughness = clamp(perceptualRoughness, c_MinRoughness, 1.0);
+ metallic = clamp(metallic, 0.0, 1.0);
+
+ // Roughness is authored as perceptual roughness; as is convention,
+ // convert to material roughness by squaring the perceptual roughness [2].
+ float alphaRoughness = perceptualRoughness * perceptualRoughness;
+
+ // The albedo may be defined from a base texture or a flat color
+
+#ifdef HAS_BASECOLORMAP
+ float4 baseColor = SRGBtoLINEAR(SAMPLE_TEXTURE(baseColourTexture, input.texcoord)) * baseColorFactor;
+#else
+ float4 baseColor = baseColorFactor;
+#endif
+
+ float3 f0 = float3(0.04, 0.04, 0.04);
+ float3 diffuseColor = baseColor.rgb * (float3(1.0, 1.0, 1.0) - f0);
+
+ diffuseColor *= 1.0 - metallic;
+
+ float3 specularColor = lerp(f0, baseColor.rgb, metallic);
+
+ // Compute reflectance.
+ float reflectance = max(max(specularColor.r, specularColor.g), specularColor.b);
+
+ // For typical incident reflectance range (between 4% to 100%) set the grazing reflectance to 100% for typical fresnel effect.
+ // For very low reflectance range on highly diffuse objects (below 4%), incrementally reduce grazing reflecance to 0%.
+ float reflectance90 = clamp(reflectance * 25.0, 0.0, 1.0);
+ float3 specularEnvironmentR0 = specularColor.rgb;
+ float3 specularEnvironmentR90 = float3(1.0, 1.0, 1.0) * reflectance90;
+
+ float3 n = getNormal(input.poswithoutw, input.normal, input.texcoord); // normal at surface point
+ float3 v = normalize(camera - input.poswithoutw); // Vector from surface point to camera
+
+ float3 l = normalize(lightDir); // Vector from surface point to light
+ float3 h = normalize(l + v); // Half vector between both l and v
+ float3 reflection = -normalize(reflect(v, n));
+
+ float NdotL = clamp(dot(n, l), 0.001, 1.0);
+ float NdotV = abs(dot(n, v)) + 0.001;
+ float NdotH = clamp(dot(n, h), 0.0, 1.0);
+ float LdotH = clamp(dot(l, h), 0.0, 1.0);
+ float VdotH = clamp(dot(v, h), 0.0, 1.0);
+
+ PBRInfo pbrInputs;
+ pbrInputs.NdotL = NdotL;
+ pbrInputs.NdotV = NdotV;
+ pbrInputs.NdotH = NdotH;
+ pbrInputs.LdotH = LdotH;
+ pbrInputs.VdotH = VdotH;
+ pbrInputs.perceptualRoughness = perceptualRoughness;
+ pbrInputs.metalness = metallic;
+ pbrInputs.reflectance0 = specularEnvironmentR0;
+ pbrInputs.reflectance90 = specularEnvironmentR90;
+ pbrInputs.alphaRoughness = alphaRoughness;
+ pbrInputs.diffuseColor = diffuseColor;
+ pbrInputs.specularColor = specularColor;
+
+ // Calculate the shading terms for the microfacet specular shading model
+ float3 F = specularReflection(pbrInputs);
+
+ float G = geometricOcclusion(pbrInputs);
+ float D = microfacetDistribution(pbrInputs);
+
+ // Calculation of analytical lighting contribution
+ float3 diffuseContrib = (1.0 - F) * diffuse(pbrInputs);
+ float3 specContrib = F * G * D / (4.0 * NdotL * NdotV);
+ float3 color = NdotL * lightColour * (diffuseContrib + specContrib);
+
+
+ // Calculate lighting contribution from image based lighting source (IBL)
+#ifdef USE_IBL
+ color += getIBLContribution(pbrInputs, n, reflection);
+#endif
+
+ // Apply optional PBR terms for additional (optional) shading
+#ifdef HAS_OCCLUSIONMAP
+ float ao = SAMPLE_TEXTURE(occlusionTexture, input.texcoord).r;
+ color = lerp(color, color * ao, occlusionStrength);
+#endif
+
+#ifdef HAS_EMISSIVEMAP
+ float3 emissive = SRGBtoLINEAR(SAMPLE_TEXTURE(emissionTexture, input.texcoord)).rgb * emissiveFactor;
+ color += emissive;
+#endif
+
+ // This section uses lerp to override final color for reference app visualization
+ // of various parameters in the lighting equation.
+ color = lerp(color, F, scaleFGDSpec.x);
+ color = lerp(color, float3(G, G, G), scaleFGDSpec.y);
+ color = lerp(color, float3(D, D, D), scaleFGDSpec.z);
+ color = lerp(color, specContrib, scaleFGDSpec.w);
+ color = lerp(color, diffuseContrib, scaleDiffBaseMR.x);
+ color = lerp(color, baseColor.rgb, scaleDiffBaseMR.y);
+ color = lerp(color, float3(metallic, metallic, metallic), scaleDiffBaseMR.z);
+ color = lerp(color, float3(perceptualRoughness, perceptualRoughness, perceptualRoughness), scaleDiffBaseMR.w);
+
+ //return float4(baseColor.xyz, 1.0);
+ return float4(color, 1.0);
+}
+
+Technique PBR
+{
+ Pass pass1
+ {
+ VertexShader = compile vs_3_0 main_vs();
+ PixelShader = compile ps_3_0 main_ps();
+ }
+}
diff --git a/Importer.cs b/Importer.cs
index ce4b783..7f1b75c 100644
--- a/Importer.cs
+++ b/Importer.cs
@@ -141,98 +141,113 @@ namespace Smuggler
if (primitive.Material != null)
{
- var normalChannel = primitive.Material.FindChannel("Normal");
- if (normalChannel.HasValue)
+ //var normalChannel = primitive.Material.FindChannel("Normal");
+ //if (normalChannel.HasValue)
+ //{
+ // if (normalChannel.Value.Texture != null)
+ // {
+ // effect.NormalTexture = Texture2D.FromStream(
+ // graphicsDevice,
+ // normalChannel.Value.Texture.PrimaryImage.Content.Open()
+ // );
+ // }
+
+ // effect.NormalScale = normalChannel.Value.Parameter.X;
+ //}
+
+ //var occlusionChannel = primitive.Material.FindChannel("Occlusion");
+ //if (occlusionChannel.HasValue)
+ //{
+ // if (occlusionChannel.Value.Texture != null)
+ // {
+ // effect.OcclusionTexture = Texture2D.FromStream(
+ // graphicsDevice,
+ // occlusionChannel.Value.Texture.PrimaryImage.Content.Open()
+ // );
+ // }
+
+ // effect.OcclusionStrength = occlusionChannel.Value.Parameter.X;
+ //}
+
+ //var emissiveChannel = primitive.Material.FindChannel("Emissive");
+ //if (emissiveChannel.HasValue)
+ //{
+ // if (emissiveChannel.Value.Texture != null)
+ // {
+ // effect.EmissionTexture = Texture2D.FromStream(
+ // graphicsDevice,
+ // emissiveChannel.Value.Texture.PrimaryImage.Content.Open()
+ // );
+ // }
+
+ // var parameter = emissiveChannel.Value.Parameter;
+
+ // effect.EmissiveFactor = new Vector3(
+ // parameter.X,
+ // parameter.Y,
+ // parameter.Z
+ // );
+ //}
+
+ var albedoChannel = primitive.Material.FindChannel("BaseColor");
+ if (albedoChannel.HasValue)
{
- if (normalChannel.Value.Texture != null)
- {
- effect.NormalTexture = Texture2D.FromStream(
- graphicsDevice,
- normalChannel.Value.Texture.PrimaryImage.Content.Open()
- );
- }
+ //if (albedoChannel.Value.Texture != null)
+ //{
+ // effect.BaseColourTexture = Texture2D.FromStream(
+ // graphicsDevice,
+ // albedoChannel.Value.Texture.PrimaryImage.Content.Open()
+ // );
+ //}
- effect.NormalScale = normalChannel.Value.Parameter.X;
- }
+ var parameter = albedoChannel.Value.Parameter;
- var occlusionChannel = primitive.Material.FindChannel("Occlusion");
- if (occlusionChannel.HasValue)
- {
- if (occlusionChannel.Value.Texture != null)
- {
- effect.OcclusionTexture = Texture2D.FromStream(
- graphicsDevice,
- occlusionChannel.Value.Texture.PrimaryImage.Content.Open()
- );
- }
-
- effect.OcclusionStrength = occlusionChannel.Value.Parameter.X;
- }
-
- var emissiveChannel = primitive.Material.FindChannel("Emissive");
- if (emissiveChannel.HasValue)
- {
- if (emissiveChannel.Value.Texture != null)
- {
- effect.EmissionTexture = Texture2D.FromStream(
- graphicsDevice,
- emissiveChannel.Value.Texture.PrimaryImage.Content.Open()
- );
- }
-
- var parameter = emissiveChannel.Value.Parameter;
-
- effect.EmissiveFactor = new Vector3(
+ effect.Albedo = new Vector3(
parameter.X,
parameter.Y,
parameter.Z
);
}
- var baseColorChannel = primitive.Material.FindChannel("BaseColor");
- if (baseColorChannel.HasValue)
- {
- if (baseColorChannel.Value.Texture != null)
- {
- effect.BaseColourTexture = Texture2D.FromStream(
- graphicsDevice,
- baseColorChannel.Value.Texture.PrimaryImage.Content.Open()
- );
- }
-
- var parameter = baseColorChannel.Value.Parameter;
-
- effect.BaseColorFactor = new Vector4(
- parameter.X,
- parameter.Y,
- parameter.Z,
- parameter.W
- );
- }
-
var metallicRoughnessChannel = primitive.Material.FindChannel("MetallicRoughness");
if (metallicRoughnessChannel.HasValue)
{
- if (metallicRoughnessChannel.Value.Texture != null)
- {
- effect.MetallicRoughnessTexture = Texture2D.FromStream(
- graphicsDevice,
- metallicRoughnessChannel.Value.Texture.PrimaryImage.Content.Open()
- );
- }
+ //if (metallicRoughnessChannel.Value.Texture != null)
+ //{
+ // effect.MetallicRoughnessTexture = Texture2D.FromStream(
+ // graphicsDevice,
+ // metallicRoughnessChannel.Value.Texture.PrimaryImage.Content.Open()
+ // );
+ //}
var parameter = metallicRoughnessChannel.Value.Parameter;
- effect.MetallicRoughnessValue = new Vector2(
- parameter.X,
- parameter.Y
- );
+ effect.Metallic = parameter.X;
+ effect.Roughness = parameter.Y;
}
}
- effect.Light = new PBRLight(
- new Vector3(0.5f, 0.5f, -0.5f),
- new Vector3(10f, 10f, 10f)
+ effect.Albedo = new Vector3(0.5f, 0, 0);
+ effect.AO = 1f;
+
+ effect.Lights[0] = new PBRLight(
+ new Vector3(-10f, 10f, 10f),
+ new Vector3(300f, 300f, 300f)
+ );
+
+ effect.Lights[1] = new PBRLight(
+ new Vector3(10f, 10f, 10f),
+ new Vector3(300f, 300f, 300f)
+ );
+
+ effect.Lights[2] = new PBRLight(
+ new Vector3(-10f, -10f, 10f),
+ new Vector3(300f, 300f, 300f)
+ );
+
+ effect.Lights[3] = new PBRLight(
+ new Vector3(10f, -10f, 10f),
+ new Vector3(300f, 300f, 300f)
);
/* FIXME: how to load cube maps from GLTF? */
diff --git a/Smuggler.csproj b/Smuggler.csproj
index 59eef25..e5628ef 100644
--- a/Smuggler.csproj
+++ b/Smuggler.csproj
@@ -8,6 +8,7 @@
Cassandra Lugo and Evan Hemsley 2020
true
Smuggler
+ AnyCPU;x86
@@ -15,7 +16,7 @@
-
+