Initial project import

node_modules/@react-three/drei/core/useBoxProjectedEnv.js

@@ -0,0 +1,95 @@
+import * as THREE from 'three';
+import * as React from 'react';
+import { applyProps } from '@react-three/fiber';
+
+// credits for the box-projecting shader code go to codercat (https://codercat.tk)
+// and @0beqz https://gist.github.com/0beqz/8d51b4ae16d68021a09fb504af708fca
+
+const worldposReplace = /* glsl */`
+#if defined( USE_ENVMAP ) || defined( DISTANCE ) || defined ( USE_SHADOWMAP )
+  vec4 worldPosition = modelMatrix * vec4( transformed, 1.0 );
+  #ifdef BOX_PROJECTED_ENV_MAP
+    vWorldPosition = worldPosition.xyz;
+  #endif
+#endif
+`;
+const boxProjectDefinitions = /*glsl */`
+#ifdef BOX_PROJECTED_ENV_MAP
+  uniform vec3 envMapSize;
+  uniform vec3 envMapPosition;
+  varying vec3 vWorldPosition;
+    
+  vec3 parallaxCorrectNormal( vec3 v, vec3 cubeSize, vec3 cubePos ) {
+    vec3 nDir = normalize( v );
+    vec3 rbmax = ( .5 * cubeSize + cubePos - vWorldPosition ) / nDir;
+    vec3 rbmin = ( -.5 * cubeSize + cubePos - vWorldPosition ) / nDir;
+    vec3 rbminmax;
+    rbminmax.x = ( nDir.x > 0. ) ? rbmax.x : rbmin.x;
+    rbminmax.y = ( nDir.y > 0. ) ? rbmax.y : rbmin.y;
+    rbminmax.z = ( nDir.z > 0. ) ? rbmax.z : rbmin.z;
+    float correction = min( min( rbminmax.x, rbminmax.y ), rbminmax.z );
+    vec3 boxIntersection = vWorldPosition + nDir * correction;    
+    return boxIntersection - cubePos;
+  }
+#endif
+`;
+
+// will be inserted after "vec3 worldNormal = inverseTransformDirection( normal, viewMatrix );"
+const getIBLIrradiance_patch = /* glsl */`
+#ifdef BOX_PROJECTED_ENV_MAP
+  worldNormal = parallaxCorrectNormal( worldNormal, envMapSize, envMapPosition );
+#endif
+`;
+
+// will be inserted after "reflectVec = inverseTransformDirection( reflectVec, viewMatrix );"
+const getIBLRadiance_patch = /* glsl */`
+#ifdef BOX_PROJECTED_ENV_MAP
+  reflectVec = parallaxCorrectNormal( reflectVec, envMapSize, envMapPosition );
+#endif
+`;
+
+// FIXME Replace with `THREE.WebGLProgramParametersWithUniforms` type when able to target @types/three@0.160.0
+
+function boxProjectedEnvMap(shader, envMapPosition, envMapSize) {
+  // defines
+  shader.defines.BOX_PROJECTED_ENV_MAP = true;
+  // uniforms
+  shader.uniforms.envMapPosition = {
+    value: envMapPosition
+  };
+  shader.uniforms.envMapSize = {
+    value: envMapSize
+  };
+  // vertex shader
+  shader.vertexShader = `
+  varying vec3 vWorldPosition;
+  ${shader.vertexShader.replace('#include <worldpos_vertex>', worldposReplace)}`;
+  // fragment shader
+  shader.fragmentShader = `
+    ${boxProjectDefinitions}
+    ${shader.fragmentShader.replace('#include <envmap_physical_pars_fragment>', THREE.ShaderChunk.envmap_physical_pars_fragment).replace('vec3 worldNormal = inverseTransformDirection( normal, viewMatrix );', `vec3 worldNormal = inverseTransformDirection( normal, viewMatrix );
+         ${getIBLIrradiance_patch}
+         `).replace('reflectVec = inverseTransformDirection( reflectVec, viewMatrix );', `reflectVec = inverseTransformDirection( reflectVec, viewMatrix );
+         ${getIBLRadiance_patch}
+        `)}`;
+}
+function useBoxProjectedEnv(position = new THREE.Vector3(), size = new THREE.Vector3()) {
+  const [config] = React.useState(() => ({
+    position: new THREE.Vector3(),
+    size: new THREE.Vector3()
+  }));
+  applyProps(config, {
+    position,
+    size
+  });
+  const ref = React.useRef(null);
+  const spread = React.useMemo(() => ({
+    ref,
+    onBeforeCompile: shader => boxProjectedEnvMap(shader, config.position, config.size),
+    customProgramCacheKey: () => JSON.stringify(config.position.toArray()) + JSON.stringify(config.size.toArray())
+  }), [...config.position.toArray(), ...config.size.toArray()]);
+  React.useLayoutEffect(() => void (ref.current.needsUpdate = true), [config]);
+  return spread;
+}
+
+export { useBoxProjectedEnv };