stuff

2026-11-02 19:35:36 -05:00
parent a6103e453d
commit 7b32ad674e
52 changed files with 3285 additions and 1488 deletions
@@ -12,7 +12,42 @@ struct DirLight {
    float intensity;
 };

-uniform DirLight dirLight;
+struct PointLight {
+    vec3 position;
+    vec3 color;
+    float intensity;
+    float radius;
+    int shadowTile;
+};
+
+struct SpotLight {
+    vec3 position;
+    vec3 direction;
+    vec3 color;
+    float intensity;
+    float radius;
+    float innerCos;
+    float outerCos;
+    int shadowTile;
+};
+
+// The array sizes have to match Light.h
+#define MAX_DIRECTIONAL_LIGHTS 4
+#define MAX_POINT_LIGHTS 16
+#define MAX_SPOT_LIGHTS 8
+#define SHADOW_ATLAS_COLUMNS 6
+#define SHADOW_ATLAS_TILES (SHADOW_ATLAS_COLUMNS * SHADOW_ATLAS_COLUMNS)
+
+uniform DirLight dirLight;   // the sun, the only light with a shadow map
+uniform DirLight directionalLights[MAX_DIRECTIONAL_LIGHTS];
+uniform int directionalLightCount = 0;
+uniform PointLight pointLights[MAX_POINT_LIGHTS];
+uniform int pointLightCount = 0;
+uniform SpotLight spotLights[MAX_SPOT_LIGHTS];
+uniform int spotLightCount = 0;
+uniform sampler2DShadow localShadowMap;
+uniform mat4 shadowTileMatrices[SHADOW_ATLAS_TILES];
+
 uniform vec3 viewPos;

 uniform sampler2DShadow shadowMap;
@@ -23,6 +58,7 @@ uniform int useTexture = 0;
 uniform float metallic = 0.0;
 uniform float roughness = 0.7;
 uniform float ao = 1.0;
+uniform float emissive = 0.0;
 uniform float envIntensity = 0.8;

 const float PI = 3.14159265359;
@@ -72,6 +108,65 @@ vec3 EnvironmentBRDF(vec3 F0, float rough, float NdotV)
    return F0 * AB.x + AB.y;
 }

+// Light from one direction, L points from the surface toward the light
+vec3 ShadeLight(vec3 L, vec3 radiance, vec3 N, vec3 V, vec3 albedo, float metal, float rough, vec3 F0, float NdotV)
+{
+    float NdotL = max(dot(N, L), 0.0);
+    if (NdotL <= 0.0)
+        return vec3(0.0);
+
+    vec3 H = normalize(V + L);
+    vec3 F = FresnelSchlick(max(dot(H, V), 0.0), F0);
+    float NDF = DistributionGGX(N, H, rough);
+    float G = GeometrySmith(N, V, L, rough);
+    vec3 specular = (NDF * G * F) / max(4.0 * NdotV * NdotL, 1e-4);
+    vec3 kD = (vec3(1.0) - F) * (1.0 - metal);
+    return (kD * albedo / PI + specular) * radiance * NdotL;
+}
+
+// Inverse square falloff, windowed so it reaches exactly zero at the radius
+float PointAttenuation(float distanceSquared, float radius)
+{
+    float ratio = distanceSquared / (radius * radius);
+    float window = clamp(1.0 - ratio * ratio, 0.0, 1.0);
+    return window * window / max(distanceSquared, 0.01);
+}
+
+// Which of a point light's 6 atlas tiles covers offset, the order is set in RenderLocalShadows
+int PointShadowFace(vec3 offset)
+{
+    vec3 size = abs(offset);
+    if (size.x >= size.y && size.x >= size.z) return offset.x > 0.0 ? 0 : 1;
+    if (size.y >= size.z) return offset.y > 0.0 ? 2 : 3;
+    return offset.z > 0.0 ? 4 : 5;
+}
+
+// 1 = lit, 0 = shadowed. Stays inside the tile so the filter can't pick up its neighbours.
+float LocalShadow(int tile, vec3 worldPos, vec3 N)
+{
+    vec4 clipPos = shadowTileMatrices[tile] * vec4(worldPos + N * 0.04, 1.0);
+    if (clipPos.w <= 0.0)
+        return 1.0;
+
+    vec3 projCoords = clipPos.xyz / clipPos.w * 0.5 + 0.5;
+    if (any(lessThan(projCoords, vec3(0.0))) || any(greaterThan(projCoords, vec3(1.0))))
+        return 1.0;
+
+    float tileSize = 1.0 / float(SHADOW_ATLAS_COLUMNS);
+    vec2 tileOrigin = vec2(float(tile % SHADOW_ATLAS_COLUMNS), float(tile / SHADOW_ATLAS_COLUMNS)) * tileSize;
+    vec2 texelSize = 1.0 / vec2(textureSize(localShadowMap, 0));
+    vec2 uv = tileOrigin + projCoords.xy * tileSize;
+
+    float shadow = 0.0;
+    for (int x = -1; x <= 1; x++) {
+        for (int y = -1; y <= 1; y++) {
+            vec2 sampleUV = clamp(uv + vec2(x, y) * texelSize, tileOrigin + texelSize, tileOrigin + tileSize - texelSize);
+            shadow += texture(localShadowMap, vec3(sampleUV, projCoords.z - 0.0002));
+        }
+    }
+    return shadow / 9.0;
+}
+
 float ShadowCalculation(vec4 fragPosLightSpace, vec3 N, vec3 L)
 {
    vec3 projCoords = fragPosLightSpace.xyz / fragPosLightSpace.w;
@@ -112,21 +207,63 @@ void main()

    vec3 N = normalize(normal);
    vec3 V = normalize(viewPos - FragPos);
-    vec3 L = normalize(-dirLight.direction);
-    vec3 H = normalize(V + L);
    float NdotV = max(dot(N, V), 1e-4);
-    float NdotL = max(dot(N, L), 0.0);

    vec3 F0 = mix(vec3(0.04), albedo, metal);
-    vec3 F = FresnelSchlick(max(dot(H, V), 0.0), F0);
-    float NDF = DistributionGGX(N, H, rough);
-    float G = GeometrySmith(N, V, L, rough);
-    vec3 specular = (NDF * G * F) / max(4.0 * NdotV * NdotL, 1e-4);
-    vec3 kD = (vec3(1.0) - F) * (1.0 - metal);
-    vec3 radiance = dirLight.color * dirLight.intensity;
+    vec3 direct = vec3(0.0);

-    float shadow = ShadowCalculation(fragposlightspace, N, L);
-    vec3 direct = (kD * albedo / PI + specular) * radiance * NdotL * shadow;
+    // Facing away from the sun has no direct light, so skip the BRDF and the 9 shadow samples
+    vec3 sunL = normalize(-dirLight.direction);
+    if (dot(N, sunL) > 0.0) {
+        float shadow = ShadowCalculation(fragposlightspace, N, sunL);
+        direct += ShadeLight(sunL, dirLight.color * dirLight.intensity, N, V, albedo, metal, rough, F0, NdotV) * shadow;
+    }
+
+    for (int i = 0; i < directionalLightCount; i++) {
+        vec3 L = normalize(-directionalLights[i].direction);
+        vec3 radiance = directionalLights[i].color * directionalLights[i].intensity;
+        direct += ShadeLight(L, radiance, N, V, albedo, metal, rough, F0, NdotV);
+    }
+
+    for (int i = 0; i < pointLightCount; i++) {
+        vec3 toLight = pointLights[i].position - FragPos;
+        float distanceSquared = dot(toLight, toLight);
+        float radius = pointLights[i].radius;
+        if (distanceSquared >= radius * radius)
+            continue;
+
+        vec3 radiance = pointLights[i].color * pointLights[i].intensity * PointAttenuation(distanceSquared, radius);
+        vec3 L = toLight / sqrt(distanceSquared);
+        if (dot(N, L) <= 0.0)
+            continue;
+
+        vec3 lit = ShadeLight(L, radiance, N, V, albedo, metal, rough, F0, NdotV);
+        if (pointLights[i].shadowTile >= 0)
+            lit *= LocalShadow(pointLights[i].shadowTile + PointShadowFace(-toLight), FragPos, N);
+        direct += lit;
+    }
+
+    for (int i = 0; i < spotLightCount; i++) {
+        vec3 toLight = spotLights[i].position - FragPos;
+        float distanceSquared = dot(toLight, toLight);
+        float radius = spotLights[i].radius;
+        if (distanceSquared >= radius * radius)
+            continue;
+
+        vec3 L = toLight / sqrt(distanceSquared);
+        float cone = smoothstep(spotLights[i].outerCos, spotLights[i].innerCos, dot(-L, spotLights[i].direction));
+        if (cone <= 0.0)
+            continue;
+
+        if (dot(N, L) <= 0.0)
+            continue;
+
+        vec3 radiance = spotLights[i].color * spotLights[i].intensity * PointAttenuation(distanceSquared, radius) * cone;
+        vec3 lit = ShadeLight(L, radiance, N, V, albedo, metal, rough, F0, NdotV);
+        if (spotLights[i].shadowTile >= 0)
+            lit *= LocalShadow(spotLights[i].shadowTile, FragPos, N);
+        direct += lit;
+    }

    vec3 ambientF = FresnelSchlickRoughness(NdotV, F0, rough);
    vec3 ambientKD = (vec3(1.0) - ambientF) * (1.0 - metal);
@@ -136,5 +273,5 @@ void main()
    vec3 specularIBL = prefiltered * EnvironmentBRDF(F0, rough, NdotV);
    vec3 ambient = (ambientKD * irradiance * albedo + specularIBL) * ao;

-    FragColor = vec4(direct + ambient, albedoSample.a);
+    FragColor = vec4(direct + ambient + albedo * emissive * 4.0, albedoSample.a);
 }