Add LUTPass

examples/jsm/loaders/LUT3dlLoader.js

@@ -3,7 +3,6 @@
 import {
 	Loader,
 	FileLoader,
-	Vector3,
 	DataTexture,
 	DataTexture3D,
 	RGBFormat,

examples/jsm/postprocessing/LUTPass.js

@@ -0,0 +1,159 @@
+import { ShaderPass } from '//unpkg.com/[email protected]/examples/jsm/postprocessing/ShaderPass.js';
+
+const LUTShader = {
+
+	defines: {
+		USE_3DTEXTURE: 1,
+	},
+
+	uniforms: {
+		lut3d: { value: null },
+
+		lut: { value: null },
+		lutSize: { value: 0 },
+
+		tDiffuse: { value: null },
+		intensity: { value: 1.0 },
+	},
+
+	vertexShader: /* glsl */`
+
+		varying vec2 vUv;
+
+		void main() {
+
+			vUv = uv;
+			gl_Position = projectionMatrix * modelViewMatrix * vec4( position, 1.0 );
+
+		}
+
+	`,
+
+
+	fragmentShader: /* glsl */`
+		precision highp sampler3D;
+
+		#if USE_3DTEXTURE
+		uniform sampler3D lut3d;
+		#else
+		uniform sampler2D lut;
+		uniform float lutSize;
+
+		vec3 lutLookup( sampler2D tex, float size, vec3 rgb ) {
+
+			// clamp the sample in by half a pixel to avoid interpolation
+			// artifacts between slices laid out next to each other.
+			float halfPixelWidth = 0.5 / size;
+			rgb.rg = clamp( rgb.rg, halfPixelWidth, 1.0 - halfPixelWidth );
+
+			// green offset into a LUT layer
+			float gOffset = rgb.g / size;
+			vec2 uv1 = vec2( rgb.r, gOffset );
+			vec2 uv2 = vec2( rgb.r, gOffset );
+
+			// adjust b slice offset
+			float bNormalized = size * rgb.b;
+			float bSlice = min( floor( size * rgb.b ), size - 1.0 );
+			float bMix = ( bNormalized - bSlice ) / size;
+
+			// get the first lut slice and then the one to interpolate to
+			float b1 = bSlice / size;
+			float b2 = ( bSlice + 1.0 ) / size;
+
+			uv1.y += b1;
+			uv2.y += b2;
+
+			vec3 sample1 = texture2D( tex, uv1 ).rgb;
+			vec3 sample2 = texture2D( tex, uv2 ).rgb;
+
+			return mix( sample1, sample2, bMix );
+
+		}
+		#endif
+
+		varying vec2 vUv;
+		uniform float intensity;
+		uniform sampler2D tDiffuse;
+		void main() {
+
+			vec4 val = texture2D( tDiffuse, vUv );
+			vec4 lutVal;
+			#if USE_3DTEXTURE
+			lutVal = vec4( texture( lut3d, val.rgb ).rgb, val.a );
+			#else
+			lutVal = vec4( lutLookup( lut, lutSize, val.rgb ), val.a );
+			#endif
+			gl_FragColor = mix( val, lutVal, intensity );
+
+		}
+
+	`,
+
+};
+
+class LUTPass extends ShaderPass {
+
+	set lut( v ) {
+
+		const material = this.material;
+		if ( v !== this.lut ) {
+
+			material.uniforms.lut3d.value = null;
+			material.uniforms.lut.value = null;
+
+			if ( v ) {
+
+				const is3dTextureDefine = v.isDataTexture3D ? 1 : 0;
+				if ( is3dTextureDefine !== material.defines.USE_3DTEXTURE ) {
+
+					material.defines.USE_3DTEXTURE = is3dTextureDefine;
+					material.needsUpdate = true;
+
+				}
+
+				if ( v.isDataTexture3D ) {
+
+					material.uniforms.lut3d.value = v;
+
+				} else {
+
+					material.uniforms.lut.value = v;
+					material.uniforms.lutSize.value = v.image.width;
+
+				}
+
+			}
+
+		}
+
+	}
+
+	get lut() {
+
+		return this.material.uniforms.lut.value || this.material.uniforms.lut3d.value;
+
+	}
+
+	set intensity( v ) {
+
+		this.material.uniforms.intensity.value = v;
+
+	}
+
+	get intensity() {
+
+		return this.material.uniforms.intensity.value;
+
+	}
+
+	constructor( options = {} ) {
+
+		super( LUTShader );
+		this.lut = options.lut || null;
+		this.intensity = 'intensity' in options ? options.intensity : 1;
+
+	}
+
+}
+
+export { LUTPass };