mirror of
https://github.com/antopilo/Nuake.git
synced 2026-01-06 06:09:52 +03:00
317 lines
8.7 KiB
GLSL
317 lines
8.7 KiB
GLSL
#shader vertex
|
|
#version 460 core
|
|
layout(location = 0) in vec3 VertexPosition;
|
|
layout(location = 1) in vec2 UVPosition;
|
|
|
|
out flat vec2 UV;
|
|
out mat4 InvProjection;
|
|
out mat4 InvView;
|
|
|
|
uniform mat4 u_Projection;
|
|
uniform mat4 u_View;
|
|
|
|
void main()
|
|
{
|
|
UV = UVPosition;
|
|
InvProjection = inverse(u_Projection);
|
|
InvView = inverse(u_View);
|
|
|
|
gl_Position = vec4(VertexPosition, 1.0f);
|
|
}
|
|
|
|
#shader fragment
|
|
#version 460 core
|
|
|
|
out vec4 FragColor;
|
|
|
|
in vec2 UV;
|
|
in mat4 InvProjection;
|
|
in mat4 InvView;
|
|
|
|
// Camera
|
|
uniform float u_Exposure;
|
|
uniform vec3 u_EyePosition;
|
|
|
|
// Environmnent
|
|
uniform float u_FogAmount;
|
|
uniform float u_FogStepCount;
|
|
uniform samplerCube u_IrradianceMap;
|
|
uniform samplerCube u_PrefilterMap;
|
|
uniform sampler2D u_BrdfLUT;
|
|
|
|
// GBuffer
|
|
uniform sampler2D m_Depth;
|
|
uniform sampler2D m_Albedo;
|
|
uniform sampler2D m_Material;
|
|
uniform sampler2D m_Normal;
|
|
|
|
// Lights
|
|
const int MaxLight = 29;
|
|
uniform int LightCount = 0;
|
|
|
|
struct Light {
|
|
int Type; // 0 = directional, 1 = point
|
|
vec3 Direction;
|
|
vec3 Color;
|
|
float Strength;
|
|
vec3 Position;
|
|
mat4 LightTransform;
|
|
int ShadowMapsIDs[4];
|
|
float CascadeDepth[4];
|
|
mat4 LightTransforms[4];
|
|
int Volumetric;
|
|
};
|
|
|
|
uniform sampler2D ShadowMaps[4];
|
|
|
|
uniform Light Lights[MaxLight];
|
|
|
|
// Converts depth to World space coords.
|
|
vec3 WorldPosFromDepth(float depth) {
|
|
float z = depth * 2.0 - 1.0;
|
|
|
|
vec4 clipSpacePosition = vec4(UV * 2.0 - 1.0, z, 1.0);
|
|
vec4 viewSpacePosition = InvProjection * clipSpacePosition;
|
|
|
|
// Perspective division
|
|
viewSpacePosition /= viewSpacePosition.w;
|
|
|
|
vec4 worldSpacePosition = InvView * viewSpacePosition;
|
|
|
|
return worldSpacePosition.xyz;
|
|
}
|
|
|
|
const float PI = 3.141592653589793f;
|
|
float height_scale = 0.02f;
|
|
|
|
float DistributionGGX(vec3 N, vec3 H, float a)
|
|
{
|
|
float a2 = a * a;
|
|
float NdotH = max(dot(N, H), 0.0);
|
|
float NdotH2 = NdotH * NdotH;
|
|
|
|
float nom = a2;
|
|
float denom = (NdotH2 * (a2 - 1.0) + 1.0);
|
|
denom = PI * denom * denom;
|
|
|
|
return nom / denom;
|
|
}
|
|
|
|
float GeometrySchlickGGX(float NdotV, float k)
|
|
{
|
|
float nom = NdotV;
|
|
float denom = NdotV * (1.0 - k) + k;
|
|
|
|
return nom / denom;
|
|
}
|
|
|
|
float GeometrySmith(vec3 N, vec3 V, vec3 L, float k)
|
|
{
|
|
float NdotV = max(dot(N, V), 0.0);
|
|
float NdotL = max(dot(N, L), 0.0);
|
|
float ggx1 = GeometrySchlickGGX(NdotV, k);
|
|
float ggx2 = GeometrySchlickGGX(NdotL, k);
|
|
|
|
return ggx1 * ggx2;
|
|
}
|
|
|
|
vec3 fresnelSchlick(float cosTheta, vec3 F0)
|
|
{
|
|
return F0 + (1.0 - F0) * pow(max(1.0 - cosTheta, 0.0), 5.0);
|
|
}
|
|
|
|
vec3 fresnelSchlickRoughness(float cosTheta, vec3 F0, float roughness)
|
|
{
|
|
return F0 + (max(vec3(1.0 - roughness), F0) - F0) * pow(max(1.0 - cosTheta, 0.0), 5.0);
|
|
}
|
|
|
|
|
|
float ShadowCalculation(Light light, vec3 FragPos, vec3 normal)
|
|
{
|
|
// Get Depth
|
|
float depth = length(FragPos - u_EyePosition);
|
|
int shadowmap = 0;
|
|
|
|
// Get CSM depth
|
|
for (int i = 0; i < 4; i++)
|
|
{
|
|
float CSMDepth = light.CascadeDepth[i];
|
|
|
|
if (depth < CSMDepth + 0.0001)
|
|
{
|
|
shadowmap = i;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (shadowmap == -1)
|
|
return 1.0;
|
|
|
|
vec4 fragPosLightSpace = light.LightTransforms[0] * vec4(FragPos, 1.0f);
|
|
|
|
// perform perspective divide
|
|
vec3 projCoords = fragPosLightSpace.xyz / fragPosLightSpace.w;
|
|
// transform to [0,1] range
|
|
projCoords = projCoords * 0.5 + 0.5;
|
|
// get closest depth value from light's perspective (using [0,1] range fragPosLight as coords)
|
|
// get depth of current fragment from light's perspective
|
|
float currentDepth = projCoords.z;
|
|
// check whether current frag pos is in shadow
|
|
float bias = max(0.005 * (1.0 - dot(normal, light.Direction)), 0.0005);
|
|
|
|
float shadow = 0.0;
|
|
|
|
float pcfDepth = texture(ShadowMaps[0], projCoords.xy).r;
|
|
return currentDepth - bias > pcfDepth ? 1.0 : 0.0;
|
|
}
|
|
|
|
// Mie scaterring approximated with Henyey-Greenstein phase function.
|
|
float ComputeScattering(float lightDotView)
|
|
{
|
|
float result = 1.0f - u_FogAmount * u_FogAmount;
|
|
result /= (4.0f * PI * pow(1.0f + u_FogAmount * u_FogAmount - (2.0f * u_FogAmount) * lightDotView, 1.5f));
|
|
return result;
|
|
}
|
|
|
|
|
|
vec3 ComputeVolumetric(vec3 FragPos, Light light)
|
|
{
|
|
// world space frag position.
|
|
vec3 startPosition = u_EyePosition; // Camera Position
|
|
vec3 rayVector = FragPos - startPosition; // Ray Direction
|
|
|
|
float rayLength = length(rayVector); // Length of the raymarched
|
|
|
|
float stepLength = rayLength / u_FogStepCount; // Step length
|
|
vec3 rayDirection = rayVector / rayLength;
|
|
vec3 step = rayDirection * stepLength; // Normalized to step length direction
|
|
|
|
vec3 currentPosition = startPosition; // First step position
|
|
vec3 accumFog = vec3(0.0f, 0.0f, 0.0f); // accumulative color
|
|
|
|
// Raymarching
|
|
for (int i = 0; i < u_FogStepCount; i++)
|
|
{
|
|
vec4 fragPosLightSpace = light.LightTransforms[0] * vec4(currentPosition, 1.0f);
|
|
// perform perspective divide
|
|
vec3 projCoords = fragPosLightSpace.xyz / fragPosLightSpace.w;
|
|
// transform to [0,1] range
|
|
projCoords = projCoords * 0.5 + 0.5;
|
|
|
|
float currentDepth = projCoords.z;
|
|
|
|
// get closest depth value from light's perspective (using [0,1] range fragPosLight as coords)
|
|
vec2 texelSize = 1.0 / textureSize(ShadowMaps[0], 0);
|
|
|
|
float closestDepth = texture(ShadowMaps[0], projCoords.xy).r;
|
|
|
|
if (closestDepth > currentDepth)
|
|
accumFog += (ComputeScattering(dot(rayDirection, light.Direction)).xxx * light.Color);
|
|
|
|
//float ditherPattern[4][4] = {
|
|
// { 0.0f, 0.5f, 0.125f, 0.625f},
|
|
// { 0.75f, 0.22f, 0.875f, 0.375f},
|
|
// { 0.1875f, 0.6875f, 0.0625f, 0.5625},
|
|
// { 0.9375f, 0.4375f, 0.8125f, 0.3125}
|
|
//};
|
|
|
|
currentPosition += step; //* ditherPattern[int(gl_FragCoord.x) % 4][int(gl_FragCoord.y) % 4];
|
|
}
|
|
accumFog /= u_FogStepCount;
|
|
|
|
return accumFog;
|
|
}
|
|
|
|
void main()
|
|
{
|
|
vec3 worldPos = WorldPosFromDepth(texture(m_Depth, UV).r);
|
|
|
|
if (texture(m_Depth, UV).r == 1)
|
|
{
|
|
FragColor = vec4(0, 0, 0, 0);
|
|
return;
|
|
}
|
|
|
|
// Convert from [0, 1] to [-1, 1].
|
|
vec3 albedo = texture(m_Albedo, UV).rgb;
|
|
vec3 normal = texture(m_Normal, UV).rgb * 2.0 - 1.0;
|
|
float metallic = texture(m_Material, UV).r;
|
|
float roughness = texture(m_Material, UV).b;
|
|
float ao = texture(m_Material, UV).g;
|
|
|
|
vec3 N = normal;
|
|
vec3 V = normalize(u_EyePosition - worldPos);
|
|
vec3 R = reflect(-V, N);
|
|
vec3 F0 = vec3(0.04);
|
|
F0 = mix(F0, albedo, metallic);
|
|
|
|
// reflectance equation
|
|
vec3 Lo = vec3(0.0);
|
|
vec3 fog = vec3(0.0);
|
|
float shadow = 0.0f;
|
|
|
|
vec3 eyeDirection = normalize(u_EyePosition - worldPos);
|
|
|
|
for (int i = 0; i < LightCount; i++)
|
|
{
|
|
vec3 L = normalize(Lights[i].Position - worldPos);
|
|
|
|
float distance = length(Lights[i].Position - worldPos);
|
|
float attenuation = 1.0 / (distance * distance);
|
|
|
|
if (Lights[i].Type == 0) {
|
|
L = normalize(Lights[i].Direction);
|
|
attenuation = 1.0f;
|
|
|
|
if (Lights[i].Volumetric == 1)
|
|
fog += ComputeVolumetric(worldPos, Lights[i]);
|
|
|
|
shadow += ShadowCalculation(Lights[i], worldPos, N);
|
|
}
|
|
|
|
vec3 radiance = Lights[i].Color * attenuation ;
|
|
|
|
if (Lights[i].Type == 0) {
|
|
radiance *= 1.0f - shadow;
|
|
}
|
|
|
|
// Cook-Torrance BRDF
|
|
vec3 H = normalize(V + L);
|
|
float NDF = DistributionGGX(N, H, roughness);
|
|
float G = GeometrySmith(N, V, L, roughness);
|
|
vec3 F = fresnelSchlick(max(dot(H, V), 0.0), F0);
|
|
|
|
vec3 nominator = NDF * G * F;
|
|
float denominator = 4 * max(dot(N, V), 0.0) * max(dot(N, L), 0.0) + 0.001; // 0.001 to prevent divide by zero.
|
|
vec3 specular = nominator / denominator;
|
|
|
|
// kS is equal to Fresnel
|
|
vec3 kS = F;
|
|
vec3 kD = vec3(1.0) - kS;
|
|
kD *= 1.0 - metallic;
|
|
|
|
// scale light by NdotL
|
|
float NdotL = max(dot(N, L), 0.0);
|
|
Lo += (kD * albedo / PI + specular) * radiance * NdotL;// note that we already multiplied the BRDF by the Fresnel (kS) so we won't multiply by kS again
|
|
}
|
|
|
|
/// ambient lighting (we now use IBL as the ambient term)
|
|
vec3 F = fresnelSchlickRoughness(max(dot(N, V), 0.0), F0, roughness);
|
|
|
|
vec3 kS = F;
|
|
vec3 kD = 1.0 - kS;
|
|
kD *= 1.0 - metallic;
|
|
|
|
vec3 ambient = (kD * albedo) * ao;
|
|
vec3 color = ambient + Lo;
|
|
color += fog;
|
|
|
|
//color = color / (color + vec3(1.0));
|
|
//const float gamma = 2.2;
|
|
//// HDR tonemapping
|
|
//color = vec3(1.0) - exp(-color * 1.0);
|
|
//// gamma correct
|
|
//color = pow(color, vec3(1.0 / gamma));
|
|
|
|
FragColor = mix(vec4(color, 1.0), vec4(albedo, 1.0), 0);
|
|
} |