| import { |
| PlaneGeometry, |
| ShaderMaterial, |
| Uniform, |
| Mesh, |
| PerspectiveCamera, |
| Scene, |
| WebGLRenderer, |
| CanvasTexture, |
| SRGBColorSpace |
| } from 'three'; |
|
|
| let _renderer; |
| let fullscreenQuadGeometry; |
| let fullscreenQuadMaterial; |
| let fullscreenQuad; |
|
|
| export function decompress( texture, maxTextureSize = Infinity, renderer = null ) { |
|
|
| if ( ! fullscreenQuadGeometry ) fullscreenQuadGeometry = new PlaneGeometry( 2, 2, 1, 1 ); |
| if ( ! fullscreenQuadMaterial ) fullscreenQuadMaterial = new ShaderMaterial( { |
| uniforms: { blitTexture: new Uniform( texture ) }, |
| vertexShader: ` |
| varying vec2 vUv; |
| void main(){ |
| vUv = uv; |
| gl_Position = vec4(position.xy * 1.0,0.,.999999); |
| }`, |
| fragmentShader: ` |
| uniform sampler2D blitTexture; |
| varying vec2 vUv; |
| |
| void main(){ |
| gl_FragColor = vec4(vUv.xy, 0, 1); |
| |
| #ifdef IS_SRGB |
| gl_FragColor = LinearTosRGB( texture2D( blitTexture, vUv) ); |
| #else |
| gl_FragColor = texture2D( blitTexture, vUv); |
| #endif |
| }` |
| } ); |
|
|
| fullscreenQuadMaterial.uniforms.blitTexture.value = texture; |
| fullscreenQuadMaterial.defines.IS_SRGB = texture.colorSpace == SRGBColorSpace; |
| fullscreenQuadMaterial.needsUpdate = true; |
|
|
| if ( ! fullscreenQuad ) { |
|
|
| fullscreenQuad = new Mesh( fullscreenQuadGeometry, fullscreenQuadMaterial ); |
| fullscreenQuad.frustrumCulled = false; |
|
|
| } |
|
|
| const _camera = new PerspectiveCamera(); |
| const _scene = new Scene(); |
| _scene.add( fullscreenQuad ); |
|
|
| if ( renderer === null ) { |
|
|
| renderer = _renderer = new WebGLRenderer( { antialias: false } ); |
|
|
| } |
|
|
| const width = Math.min( texture.image.width, maxTextureSize ); |
| const height = Math.min( texture.image.height, maxTextureSize ); |
|
|
| renderer.setSize( width, height ); |
| renderer.clear(); |
| renderer.render( _scene, _camera ); |
|
|
| const canvas = document.createElement( 'canvas' ); |
| const context = canvas.getContext( '2d' ); |
|
|
| canvas.width = width; |
| canvas.height = height; |
|
|
| context.drawImage( renderer.domElement, 0, 0, width, height ); |
|
|
| const readableTexture = new CanvasTexture( canvas ); |
|
|
| readableTexture.minFilter = texture.minFilter; |
| readableTexture.magFilter = texture.magFilter; |
| readableTexture.wrapS = texture.wrapS; |
| readableTexture.wrapT = texture.wrapT; |
| readableTexture.name = texture.name; |
|
|
| if ( _renderer ) { |
|
|
| _renderer.forceContextLoss(); |
| _renderer.dispose(); |
| _renderer = null; |
|
|
| } |
|
|
| return readableTexture; |
|
|
| } |
|
|
