atdunbg
9269afaa18
- pre-filter：GGX 重要性采样（Hammersley + van der Corput 位反转）， 128²×5 mip 分级 roughness，采样数 32<<mip 上限 256；UploadCube 泛化 支持 mip 链（[mip: 6面] 紧凑排布逐 mip 逐面拷贝） - BRDF LUT：128² R16G16Sfloat 积分表（(NdotV,roughness)→F 缩放/偏置）， 纯数学与环境无关，中性兜底同样生成；专用 clamp-to-edge 采样器 （共享 border 白采样器在 uv=1.0 混入白色导致高 roughness 偏大） - shader：specular = prefiltered(R, roughness×4) × (F·A+B)， ambient = (diffuse + specular) × ambientColor - Hammersley 分母修正为当次积分采样数（低 mip 偏差 bug） - Debug 构建预积分 26s→14s（采样预算收敛 + pow 改乘法链； env 1024² 重采样为大头，compute 迁移后归零）
196 lines
7.6 KiB
GLSL
196 lines
7.6 KiB
GLSL
#version 450
|
||
|
||
const int MAX_LIGHTS = 4;
|
||
const float PI = 3.14159265359;
|
||
|
||
struct Light {
|
||
vec4 color; // rgb = 颜色，a = 强度
|
||
vec4 direction; // 方向光：xyz = 方向（已归一）
|
||
vec4 position; // 点光：xyz = 世界位置
|
||
vec4 params; // x = 类型(0=方向,1=点)，y = 衰减半径
|
||
};
|
||
|
||
layout(location = 0) in vec2 fragUV;
|
||
layout(location = 1) in vec3 fragNormal;
|
||
layout(location = 2) in vec3 fragWorldPos;
|
||
layout(location = 3) in float fragViewDepth;
|
||
layout(location = 4) in vec2 fragVelocity;
|
||
layout(location = 5) in vec3 fragTangent;
|
||
|
||
layout(location = 0) out vec4 outColor;
|
||
layout(location = 1) out vec2 outVelocity; // TAA velocity 附件
|
||
|
||
layout(set = 0, binding = 0) uniform UniformBufferObject {
|
||
mat4 view;
|
||
mat4 proj;
|
||
mat4 lightSpace[3]; // CSM 各级联光空间 VP
|
||
vec4 cascadeSplits; // xyz = 级联 0..2 远边界（视图深度）
|
||
vec4 ambientColor;
|
||
Light lights[MAX_LIGHTS];
|
||
mat4 projNoJitter;
|
||
mat4 prevView;
|
||
mat4 prevProj;
|
||
vec4 cameraPos;
|
||
} ubo;
|
||
|
||
// 材质纹理槽（binding = Material::Slot）
|
||
layout(set = 1, binding = 0) uniform sampler2D albedoMap;
|
||
layout(set = 1, binding = 1) uniform sampler2D normalMap;
|
||
layout(set = 1, binding = 2) uniform sampler2D metallicRoughnessMap; // G=粗糙度 B=金属度
|
||
layout(set = 1, binding = 3) uniform sampler2D emissiveMap;
|
||
layout(set = 1, binding = 4) uniform MaterialParams {
|
||
vec4 factors; // x = metallic 因子，y = roughness 因子
|
||
} matParams;
|
||
|
||
layout(set = 2, binding = 0) uniform sampler2D shadowMap0; // CSM 级联 0（最近）
|
||
layout(set = 2, binding = 1) uniform sampler2D shadowMap1; // 级联 1
|
||
layout(set = 2, binding = 2) uniform sampler2D shadowMap2; // 级联 2（最远）
|
||
layout(set = 2, binding = 3) uniform samplerCube irradianceMap; // 漫反射环境光（IBL 阶段②）
|
||
layout(set = 2, binding = 4) uniform samplerCube prefilteredMap; // 镜面环境（mip 分 roughness，阶段③）
|
||
layout(set = 2, binding = 5) uniform sampler2D brdfLut; // BRDF 积分表 (NdotV, roughness) → (scale, bias)
|
||
|
||
// 第 0 盏方向光（KeyLight）的 CSM 阴影因子：0.3 影中 / 1.0 受光。
|
||
// 级联按视图深度选择；采样器均 clamp-to-border 白色：
|
||
// 光视锥外自动 1.0（无阴影），省出界分支。
|
||
float ShadowFactor(vec3 N, float viewDepth) {
|
||
int cascade = 2;
|
||
for (int i = 0; i < 3; ++i) {
|
||
if (viewDepth < ubo.cascadeSplits[i]) { cascade = i; break; }
|
||
}
|
||
|
||
vec4 ls = ubo.lightSpace[cascade] * vec4(fragWorldPos, 1.0);
|
||
vec3 proj = ls.xyz / ls.w;
|
||
vec2 uv = proj.xy * 0.5 + 0.5;
|
||
|
||
float closest;
|
||
if (cascade == 0) closest = texture(shadowMap0, uv).r;
|
||
else if (cascade == 1) closest = texture(shadowMap1, uv).r;
|
||
else closest = texture(shadowMap2, uv).r;
|
||
|
||
vec3 L = normalize(-ubo.lights[0].direction.xyz);
|
||
float bias = max(0.004 * (1.0 - dot(N, L)), 0.0012);
|
||
|
||
return (proj.z - bias > closest) ? 0.3 : 1.0;
|
||
}
|
||
|
||
// 法线贴图 → 世界空间法线（TBN 构建）。
|
||
// 无切线数据（零向量）或平法线贴图时退回几何法线。
|
||
vec3 MappedNormal(vec3 geomN, vec3 T, vec2 uv) {
|
||
if (dot(T, T) < 1e-4) return geomN;
|
||
|
||
vec3 N = geomN;
|
||
vec3 nT = normalize(T - N * dot(N, T)); // 正交化
|
||
vec3 B = cross(N, nT);
|
||
vec3 sampled = texture(normalMap, uv).xyz * 2.0 - 1.0;
|
||
if (dot(sampled, sampled) < 1e-4) return geomN;
|
||
|
||
return normalize(nT * sampled.x + B * sampled.y + N * sampled.z);
|
||
}
|
||
|
||
// ---- Cook-Torrance BRDF 各项 ----
|
||
float DistributionGGX(float NdotH, float roughness) {
|
||
float a = roughness * roughness;
|
||
float a2 = a * a;
|
||
float d = NdotH * NdotH * (a2 - 1.0) + 1.0;
|
||
return a2 / (PI * d * d);
|
||
}
|
||
|
||
float GeometrySmith(float NdotV, float NdotL, float roughness) {
|
||
float r = roughness + 1.0;
|
||
float k = (r * r) / 8.0; // 解析光源用此 k（IBL 才用 IBL 版本）
|
||
float gv = NdotV / (NdotV * (1.0 - k) + k);
|
||
float gl = NdotL / (NdotL * (1.0 - k) + k);
|
||
return gv * gl;
|
||
}
|
||
|
||
vec3 FresnelSchlick(float cosTheta, vec3 F0) {
|
||
return F0 + (1.0 - F0) * pow(clamp(1.0 - cosTheta, 0.0, 1.0), 5.0);
|
||
}
|
||
|
||
// 粗糙度感知的 Fresnel（IBL 用）：粗糙表面掠射边缘的 F 上升更平缓
|
||
vec3 FresnelSchlickRoughness(float cosTheta, vec3 F0, float roughness) {
|
||
vec3 Fmax = max(vec3(1.0 - roughness), F0);
|
||
return F0 + (Fmax - F0) * pow(clamp(1.0 - cosTheta, 0.0, 1.0), 5.0);
|
||
}
|
||
|
||
void main() {
|
||
vec3 albedo = texture(albedoMap, fragUV).rgb;
|
||
vec4 mr = texture(metallicRoughnessMap, fragUV);
|
||
float roughness = clamp(mr.g * matParams.factors.y, 0.045, 1.0);
|
||
float metallic = clamp(mr.b * matParams.factors.x, 0.0, 1.0);
|
||
vec3 emissive = texture(emissiveMap, fragUV).rgb;
|
||
|
||
vec3 N = MappedNormal(normalize(fragNormal), fragTangent, fragUV);
|
||
vec3 V = normalize(ubo.cameraPos.xyz - fragWorldPos);
|
||
float NdotV = max(dot(N, V), 1e-4);
|
||
vec3 F0 = mix(vec3(0.04), albedo, metallic); // 电介质基准反射率 4%
|
||
|
||
vec3 Lo = vec3(0.0);
|
||
|
||
for (int i = 0; i < MAX_LIGHTS; ++i) {
|
||
// 按类型分支：方向光无衰减；点光方向指向光源 + 平方距离衰减
|
||
vec3 L;
|
||
float atten = 1.0;
|
||
if (ubo.lights[i].params.x > 0.5) {
|
||
vec3 toLight = ubo.lights[i].position.xyz - fragWorldPos;
|
||
float d = length(toLight);
|
||
if (d >= ubo.lights[i].params.y) continue;
|
||
L = toLight / d;
|
||
float a = clamp(1.0 - (d * d) /
|
||
(ubo.lights[i].params.y * ubo.lights[i].params.y),
|
||
0.0, 1.0);
|
||
atten = a * a;
|
||
} else {
|
||
L = normalize(-ubo.lights[i].direction.xyz);
|
||
}
|
||
|
||
vec3 radiance = ubo.lights[i].color.rgb * ubo.lights[i].color.a * atten;
|
||
float NdotL = max(dot(N, L), 0.0);
|
||
if (NdotL <= 0.0) continue;
|
||
|
||
// Cook-Torrance 镜面项
|
||
vec3 H = normalize(V + L);
|
||
float NdotH = max(dot(N, H), 0.0);
|
||
float NdotH2 = max(dot(H, V), 0.0);
|
||
float D = DistributionGGX(NdotH, roughness);
|
||
float G = GeometrySmith(NdotV, NdotL, roughness);
|
||
vec3 F = FresnelSchlick(NdotH2, F0);
|
||
|
||
vec3 kS = F;
|
||
vec3 kD = (1.0 - kS) * (1.0 - metallic); // 金属不参与漫反射
|
||
vec3 specular = (D * G * F) /
|
||
max(4.0 * NdotV * NdotL, 1e-4);
|
||
|
||
// 阴影只来自第 0 盏方向光（CSM）
|
||
float shade = (i == 0 && ubo.lights[0].params.x < 0.5)
|
||
? ShadowFactor(N, fragViewDepth) : 1.0;
|
||
|
||
Lo += (kD * albedo / PI + specular) * radiance * NdotL * shade;
|
||
}
|
||
|
||
// 环境光：IBL split-sum（阶段②③）。
|
||
// 漫反射：N 采样 irradiance cube（半球 Lambert 预卷积）
|
||
// 镜面：R 采样 pre-filtered cube（mip = roughness 分级）
|
||
// × BRDF LUT 查表得 F 缩放/偏置
|
||
// ambientColor = 用户可调强度/色调乘子
|
||
vec3 F_amb = FresnelSchlickRoughness(NdotV, F0, roughness);
|
||
vec3 kD_amb = (1.0 - F_amb) * (1.0 - metallic);
|
||
|
||
vec3 irradiance = texture(irradianceMap, N).rgb;
|
||
vec3 diffuse = kD_amb * irradiance * albedo;
|
||
|
||
vec3 R = reflect(-V, N);
|
||
const float kMaxPrefilterMip = 4.0; // 与 Cubemap::kPrefilterMips - 1 同步
|
||
vec3 prefilteredColor = textureLod(prefilteredMap, R,
|
||
roughness * kMaxPrefilterMip).rgb;
|
||
vec2 envBRDF = texture(brdfLut, vec2(NdotV, roughness)).rg;
|
||
vec3 specular = prefilteredColor * (F_amb * envBRDF.x + envBRDF.y);
|
||
|
||
vec3 ambient = (diffuse + specular) * ubo.ambientColor.rgb;
|
||
|
||
vec3 color = ambient + Lo + emissive;
|
||
|
||
outColor = vec4(color, 1.0);
|
||
outVelocity = fragVelocity;
|
||
}
|