Fix texture orientation. Add AO. Fix fog transition in sky

app/InteriorInstance.tsx

@@ -7,8 +7,8 @@ import {
   getRotation,
   getScale,
 } from "@/src/mission";
-import { memo, Suspense, useEffect, useMemo } from "react";
-import { Material, Mesh, MeshBasicMaterial } from "three";
+import { memo, Suspense, useMemo } from "react";
+import { Mesh } from "three";
 import { setupColor } from "@/src/textureUtils";
 
 const FALLBACK_URL = `${BASE_URL}/black.png`;
@@ -21,23 +21,17 @@ function useInterior(interiorFile: string) {
   return useGLTF(url);
 }
 
-function InteriorTexture({ material }: { material: Material }) {
+function InteriorTexture({ materialName }: { materialName: string }) {
   let url = FALLBACK_URL;
   try {
-    url = interiorTextureToUrl(material.name);
+    url = interiorTextureToUrl(materialName);
   } catch (err) {
     console.error(err);
   }
 
   const texture = useTexture(url, (texture) => setupColor(texture));
 
-  useEffect(() => {
-    const asBasicMaterial = material as MeshBasicMaterial;
-    asBasicMaterial.map = texture;
-    asBasicMaterial.needsUpdate = true;
-  }, [material, texture]);
-
-  return <primitive object={material} attach="material" />;
+  return <meshStandardMaterial map={texture} side={2} />;
 }
 
 function InteriorMesh({ node }: { node: Mesh }) {
@@ -53,10 +47,10 @@ function InteriorMesh({ node }: { node: Mesh }) {
         >
           {Array.isArray(node.material) ? (
             node.material.map((mat, index) => (
-              <InteriorTexture key={index} material={mat} />
+              <InteriorTexture key={index} materialName={mat.name} />
             ))
           ) : (
-            <InteriorTexture material={node.material} />
+            <InteriorTexture materialName={node.material.name} />
           )}
         </Suspense>
       ) : null}

app/Mission.tsx

@@ -16,12 +16,5 @@ export function Mission({ name }: { name: string }) {
     return null;
   }
 
-  return (
-    <>
-      <hemisphereLight
-        args={["rgba(209, 237, 255, 1)", "rgba(186, 200, 181, 1)", 2]}
-      />
-      {mission.objects.map((object, i) => renderObject(object, i))}
-    </>
-  );
+  return <>{mission.objects.map((object, i) => renderObject(object, i))}</>;
 }

app/Sky.tsx

@@ -1,10 +1,10 @@
 import { ConsoleObject, getProperty } from "@/src/mission";
 import { useSettings } from "./SettingsProvider";
-import { Suspense, useMemo } from "react";
+import { Suspense, useMemo, useEffect, useRef } from "react";
 import { BASE_URL, getUrlForPath, loadDetailMapList } from "@/src/loaders";
 import { useQuery } from "@tanstack/react-query";
 import { useCubeTexture } from "@react-three/drei";
-import { Color } from "three";
+import { Color, ShaderMaterial, BackSide } from "three";
 
 const FALLBACK_URL = `${BASE_URL}/black.png`;
 
@@ -18,7 +18,15 @@ function useDetailMapList(name: string) {
   });
 }
 
-export function SkyBox({ materialList }: { materialList: string }) {
+export function SkyBox({
+  materialList,
+  fogColor,
+  fogDistance,
+}: {
+  materialList: string;
+  fogColor?: Color;
+  fogDistance?: number;
+}) {
   const { data: detailMapList } = useDetailMapList(materialList);
 
   const skyBoxFiles = useMemo(
@@ -45,7 +53,83 @@ export function SkyBox({ materialList }: { materialList: string }) {
 
   const skyBox = useCubeTexture(skyBoxFiles, { path: "" });
 
-  return <primitive attach="background" object={skyBox} />;
+  // Create a shader material for the skybox with fog
+  const materialRef = useRef<ShaderMaterial>(null!);
+
+  const hasFog = !!fogColor && !!fogDistance;
+
+  const shaderMaterial = useMemo(() => {
+    if (!hasFog) {
+      return null;
+    }
+
+    return new ShaderMaterial({
+      uniforms: {
+        skybox: { value: skyBox },
+        fogColor: { value: fogColor },
+      },
+      vertexShader: `
+        varying vec3 vDirection;
+
+        void main() {
+          // Use position directly as direction (no world transform needed)
+          vDirection = position;
+
+          // Transform position but ignore translation
+          vec4 pos = projectionMatrix * mat4(mat3(modelViewMatrix)) * vec4(position, 1.0);
+          gl_Position = pos.xyww; // Set depth to far plane
+        }
+      `,
+      fragmentShader: `
+        uniform samplerCube skybox;
+        uniform vec3 fogColor;
+
+        varying vec3 vDirection;
+
+        // Convert linear to sRGB
+        vec3 linearToSRGB(vec3 color) {
+          return pow(color, vec3(1.0 / 2.2));
+        }
+
+        void main() {
+          vec3 direction = normalize(vDirection);
+          direction.x = -direction.x;
+          vec4 skyColor = textureCube(skybox, direction);
+
+          // Calculate fog factor based on vertical direction
+          // direction.y: -1 = straight down, 0 = horizon, 1 = straight up
+          // 100% fog from bottom to horizon, then fade from horizon (0) to 0.4
+          float fogFactor = smoothstep(0.0, 0.4, direction.y);
+
+          // Mix in sRGB space to match Three.js fog rendering
+          vec3 finalColor = mix(fogColor, skyColor.rgb, fogFactor);
+          gl_FragColor = vec4(finalColor, 1.0);
+        }
+      `,
+      side: BackSide,
+      depthWrite: false,
+    });
+  }, [skyBox, fogColor, hasFog]);
+
+  // Update uniforms when fog parameters change
+  useEffect(() => {
+    if (materialRef.current && hasFog && shaderMaterial) {
+      materialRef.current.uniforms.skybox.value = skyBox;
+      materialRef.current.uniforms.fogColor.value = fogColor!;
+    }
+  }, [skyBox, fogColor, hasFog, shaderMaterial]);
+
+  // If fog is disabled, just use the skybox as background
+  if (!hasFog) {
+    return <primitive attach="background" object={skyBox} />;
+  }
+
+  return (
+    <mesh scale={5000}>
+      <sphereGeometry args={[1, 60, 40]} />
+      <primitive ref={materialRef} object={shaderMaterial} attach="material" />
+    </mesh>
+  );
 }
 
 export function Sky({ object }: { object: ConsoleObject }) {
@@ -69,12 +153,15 @@ export function Sky({ object }: { object: ConsoleObject }) {
       // `colorString` might specify an alpha value, but three.js doesn't
       // support opacity on fog or scene backgrounds, so ignore it.
       const [r, g, b] = colorString.split(" ").map((s) => parseFloat(s));
-      return new Color().setRGB(r, g, b);
+      return [
+        new Color().setRGB(r, g, b),
+        new Color().setRGB(r, g, b).convertSRGBToLinear(),
+      ];
     }
   }, [object]);
 
   const backgroundColor = fogColor ? (
-    <color attach="background" args={[fogColor]} />
+    <color attach="background" args={[fogColor[0]]} />
   ) : null;
 
   return (
@@ -83,14 +170,23 @@ export function Sky({ object }: { object: ConsoleObject }) {
         // If there's a skybox, its textures will need to load. Render just the
         // fog color as the background in the meantime.
         <Suspense fallback={backgroundColor}>
-          <SkyBox materialList={materialList} />
+          <SkyBox
+            materialList={materialList}
+            fogColor={fogEnabled ? fogColor[1] : undefined}
+            fogDistance={fogEnabled ? fogDistance : undefined}
+          />
         </Suspense>
       ) : (
         // If there's no skybox, just render the fog color as the background.
         backgroundColor
       )}
       {fogEnabled && fogDistance && fogColor ? (
-        <fog attach="fog" color={fogColor} near={0} far={fogDistance * 2} />
+        <fog
+          attach="fog"
+          color={fogColor[1]}
+          near={fogDistance / 2}
+          far={fogDistance * 2}
+        />
       ) : null}
     </>
   );

app/Sun.tsx

@@ -0,0 +1,48 @@
+import { ConsoleObject, getProperty } from "@/src/mission";
+import { useMemo } from "react";
+import { Color } from "three";
+
+export function Sun({ object }: { object: ConsoleObject }) {
+  const direction = useMemo(() => {
+    const directionStr = getProperty(object, "direction")?.value ?? "0 0 -1";
+    const [x, y, z] = directionStr.split(" ").map((s) => parseFloat(s));
+    // Scale the direction vector to position the light far from the scene
+    const scale = 5000;
+    return [x * scale, y * scale, z * scale] as [number, number, number];
+  }, [object]);
+
+  const color = useMemo(() => {
+    const colorStr = getProperty(object, "color")?.value ?? "1 1 1 1";
+    const [r, g, b] = colorStr.split(" ").map((s) => parseFloat(s));
+    return [r, g, b] as [number, number, number];
+  }, [object]);
+
+  const ambient = useMemo(() => {
+    const ambientStr = getProperty(object, "ambient")?.value ?? "0.5 0.5 0.5 1";
+    const [r, g, b] = ambientStr.split(" ").map((s) => parseFloat(s));
+    return [r, g, b] as [number, number, number];
+  }, [object]);
+
+  return (
+    <>
+      {/* Directional light for the sun */}
+      {/* <directionalLight
+        position={[500, 500, 500]}
+        target-position={direction}
+        color={color}
+        intensity={2}
+        castShadow
+        shadow-mapSize={[2048, 2048]}
+        shadow-camera-left={-2000}
+        shadow-camera-right={2000}
+        shadow-camera-top={2000}
+        shadow-camera-bottom={-2000}
+        shadow-camera-near={0.5}
+        shadow-camera-far={5000}
+        shadow-bias={-0.001}
+      /> */}
+      {/* Ambient light component */}
+      <hemisphereLight args={[new Color(...color), new Color(...ambient), 2]} />
+    </>
+  );
+}

app/TerrainBlock.tsx

@@ -209,6 +209,8 @@ export function TerrainBlock({ object }: { object: ConsoleObject }) {
       position={position}
       scale={scale}
       geometry={planeGeometry}
+      receiveShadow
+      castShadow
     >
       {terrain ? (
         <TerrainMaterial

app/page.tsx

@@ -7,6 +7,7 @@ import { ObserverControls } from "./ObserverControls";
 import { InspectorControls } from "./InspectorControls";
 import { SettingsProvider } from "./SettingsProvider";
 import { PerspectiveCamera } from "@react-three/drei";
+import { EffectComposer, N8AO } from "@react-three/postprocessing";
 
 // three.js has its own loaders for textures and models, but we need to load other
 // stuff too, e.g. missions, terrains, and more. This client is used for those.
@@ -20,7 +21,7 @@ export default function HomePage() {
     <SettingsProvider fogEnabled={fogEnabled}>
       <QueryClientProvider client={queryClient}>
         <main>
-          <Canvas>
+          <Canvas shadows>
             <ObserverControls />
             <Mission key={missionName} name={missionName} />
             <PerspectiveCamera
@@ -28,6 +29,9 @@ export default function HomePage() {
               position={[-512, 256, -512]}
               fov={90}
             />
+            <EffectComposer>
+              <N8AO intensity={3} aoRadius={3} quality="performance" />
+            </EffectComposer>
           </Canvas>
           <InspectorControls
             missionName={missionName}

app/renderObject.tsx

@@ -4,6 +4,7 @@ import { WaterBlock } from "./WaterBlock";
 import { SimGroup } from "./SimGroup";
 import { InteriorInstance } from "./InteriorInstance";
 import { Sky } from "./Sky";
+import { Sun } from "./Sun";
 
 const componentMap = {
   SimGroup,
@@ -11,6 +12,7 @@ const componentMap = {
   WaterBlock,
   InteriorInstance,
   Sky,
+  Sun,
 };
 
 export function renderObject(object: ConsoleObject, key: string | number) {

package-lock.json

@@ -11,6 +11,7 @@
       "dependencies": {
         "@react-three/drei": "^10.7.6",
         "@react-three/fiber": "^9.3.0",
+        "@react-three/postprocessing": "^3.0.4",
         "@tanstack/react-query": "^5.90.8",
         "next": "^15.5.2",
         "react": "^19.1.1",
@@ -1217,6 +1218,32 @@
       "integrity": "sha512-xFVuu11jh+xcO7JOAGJNOXld8/TcEHK/4CituBUeUb5hqxJLj9YuemAEuvm9gQ/+pgXYfbQuqAkiYu+u7YEsNA==",
       "license": "MIT"
     },
+    "node_modules/@react-three/postprocessing": {
+      "version": "3.0.4",
+      "resolved": "https://registry.npmjs.org/@react-three/postprocessing/-/postprocessing-3.0.4.tgz",
+      "integrity": "sha512-e4+F5xtudDYvhxx3y0NtWXpZbwvQ0x1zdOXWTbXMK6fFLVDd4qucN90YaaStanZGS4Bd5siQm0lGL/5ogf8iDQ==",
+      "license": "MIT",
+      "dependencies": {
+        "maath": "^0.6.0",
+        "n8ao": "^1.9.4",
+        "postprocessing": "^6.36.6"
+      },
+      "peerDependencies": {
+        "@react-three/fiber": "^9.0.0",
+        "react": "^19.0",
+        "three": ">= 0.156.0"
+      }
+    },
+    "node_modules/@react-three/postprocessing/node_modules/maath": {
+      "version": "0.6.0",
+      "resolved": "https://registry.npmjs.org/maath/-/maath-0.6.0.tgz",
+      "integrity": "sha512-dSb2xQuP7vDnaYqfoKzlApeRcR2xtN8/f7WV/TMAkBC8552TwTLtOO0JTcSygkYMjNDPoo6V01jTw/aPi4JrMw==",
+      "license": "MIT",
+      "peerDependencies": {
+        "@types/three": ">=0.144.0",
+        "three": ">=0.144.0"
+      }
+    },
     "node_modules/@swc/helpers": {
       "version": "0.5.15",
       "resolved": "https://registry.npmjs.org/@swc/helpers/-/helpers-0.5.15.tgz",
@@ -1967,6 +1994,16 @@
         "node": ">=16 || 14 >=14.17"
       }
     },
+    "node_modules/n8ao": {
+      "version": "1.10.1",
+      "resolved": "https://registry.npmjs.org/n8ao/-/n8ao-1.10.1.tgz",
+      "integrity": "sha512-hhI1pC+BfOZBV1KMwynBrVlIm8wqLxj/abAWhF2nZ0qQKyzTSQa1QtLVS2veRiuoBQXojxobcnp0oe+PUoxf/w==",
+      "license": "ISC",
+      "peerDependencies": {
+        "postprocessing": ">=6.30.0",
+        "three": ">=0.137"
+      }
+    },
     "node_modules/nanoid": {
       "version": "3.3.11",
       "resolved": "https://registry.npmjs.org/nanoid/-/nanoid-3.3.11.tgz",
@@ -2128,6 +2165,16 @@
         "node": "^10 || ^12 || >=14"
       }
     },
+    "node_modules/postprocessing": {
+      "version": "6.38.0",
+      "resolved": "https://registry.npmjs.org/postprocessing/-/postprocessing-6.38.0.tgz",
+      "integrity": "sha512-tisx8XN/PWTL3uXz2mt8bjlMS1wiOUSCK3ixi4zjwUCFmP8XW8hNhXwrxwd2zf2VmCyCQ3GUaLm7GLnkkBbDsQ==",
+      "license": "Zlib",
+      "peer": true,
+      "peerDependencies": {
+        "three": ">= 0.157.0 < 0.182.0"
+      }
+    },
     "node_modules/potpack": {
       "version": "1.0.2",
       "resolved": "https://registry.npmjs.org/potpack/-/potpack-1.0.2.tgz",

package.json

@@ -18,6 +18,7 @@
   "dependencies": {
     "@react-three/drei": "^10.7.6",
     "@react-three/fiber": "^9.3.0",
+    "@react-three/postprocessing": "^3.0.4",
     "@tanstack/react-query": "^5.90.8",
     "next": "^15.5.2",
     "react": "^19.1.1",

src/textureUtils.ts

@@ -13,6 +13,7 @@ export function setupColor(tex, repeat = [1, 1]) {
   tex.wrapS = tex.wrapT = RepeatWrapping;
   tex.colorSpace = SRGBColorSpace;
   tex.repeat.set(...repeat);
+  tex.flipY = false; // DDS/DIF textures are already flipped
   tex.anisotropy = 16;
   tex.generateMipmaps = true;
   tex.minFilter = LinearMipmapLinearFilter;