https://github.com/WWBN/AVideo/issues/8713

node_modules/three/examples/js/shaders/NormalMapShader.js

@@ -0,0 +1,51 @@
+/**
+ * Normal map shader
+ * - compute normals from heightmap
+ */
+
+THREE.NormalMapShader = {
+
+	uniforms: {
+
+		'heightMap': { value: null },
+		'resolution': { value: new THREE.Vector2( 512, 512 ) },
+		'scale': { value: new THREE.Vector2( 1, 1 ) },
+		'height': { value: 0.05 }
+
+	},
+
+	vertexShader: [
+
+		'varying vec2 vUv;',
+
+		'void main() {',
+
+		'	vUv = uv;',
+		'	gl_Position = projectionMatrix * modelViewMatrix * vec4( position, 1.0 );',
+
+		'}'
+
+	].join( '\n' ),
+
+	fragmentShader: [
+
+		'uniform float height;',
+		'uniform vec2 resolution;',
+		'uniform sampler2D heightMap;',
+
+		'varying vec2 vUv;',
+
+		'void main() {',
+
+		'	float val = texture2D( heightMap, vUv ).x;',
+
+		'	float valU = texture2D( heightMap, vUv + vec2( 1.0 / resolution.x, 0.0 ) ).x;',
+		'	float valV = texture2D( heightMap, vUv + vec2( 0.0, 1.0 / resolution.y ) ).x;',
+
+		'	gl_FragColor = vec4( ( 0.5 * normalize( vec3( val - valU, val - valV, height  ) ) + 0.5 ), 1.0 );',
+
+		'}'
+
+	].join( '\n' )
+
+};