|
| 1 | +function readFileAsDataURL(file) { |
| 2 | + return new Promise((resolve, reject) => { |
| 3 | + const reader = new FileReader(); |
| 4 | + |
| 5 | + reader.onload = () => { |
| 6 | + resolve(reader.result); |
| 7 | + }; |
| 8 | + |
| 9 | + reader.onerror = reject; |
| 10 | + |
| 11 | + reader.readAsDataURL(file); |
| 12 | + }); |
| 13 | +} |
| 14 | + |
| 15 | +function createImageFromAsDataURL(dataURL) { |
| 16 | + return new Promise((resolve, reject) => { |
| 17 | + const image = new Image(); |
| 18 | + |
| 19 | + image.onload = () => { |
| 20 | + resolve(image); |
| 21 | + }; |
| 22 | + |
| 23 | + image.onerror = reject; |
| 24 | + |
| 25 | + image.src = dataURL; |
| 26 | + }); |
| 27 | +} |
| 28 | + |
| 29 | +function drawImage({ image, canvas }) { |
| 30 | + const context = canvas.getContext('2d'); |
| 31 | + context.drawImage(image, 0, 0); |
| 32 | +} |
| 33 | + |
| 34 | +function getImageData(canvas) { |
| 35 | + const context = canvas.getContext('2d'); |
| 36 | + return context.getImageData(0, 0, canvas.width, canvas.height); |
| 37 | +} |
| 38 | + |
| 39 | +const vertexShader = ` |
| 40 | + varying vec2 vCoord; |
| 41 | +
|
| 42 | + void main() { |
| 43 | + vCoord = uv; |
| 44 | + gl_Position = projectionMatrix * modelViewMatrix * vec4(position, 1.0); |
| 45 | + } |
| 46 | +`; |
| 47 | + |
| 48 | +const fragmentShader = ` |
| 49 | + uniform sampler2D uImage; |
| 50 | + uniform sampler2D uFilter; |
| 51 | + varying vec2 vCoord; |
| 52 | +
|
| 53 | + vec4 filterColor(vec4 color) { |
| 54 | + float r = floor(color.r * 255.0); |
| 55 | + float g = floor(color.g * 255.0); |
| 56 | + float b = floor(color.b * 255.0); |
| 57 | +
|
| 58 | + float x = r + mod(b, 16.0) * 256.0 + 0.5; |
| 59 | + float y = g + floor(b / 16.0) * 256.0 + 0.5; |
| 60 | +
|
| 61 | + vec2 coord = vec2(x / 4096.0, 1.0 - (y / 4096.0)); |
| 62 | +
|
| 63 | + return texture2D(uFilter, coord); |
| 64 | + } |
| 65 | +
|
| 66 | + void main() { |
| 67 | + vec4 color = texture2D(uImage, vCoord); |
| 68 | + if (vCoord.x > 0.0) { |
| 69 | + color = filterColor(color); |
| 70 | + } |
| 71 | + gl_FragColor = color; |
| 72 | + } |
| 73 | +`; |
| 74 | + |
| 75 | +function createTexture(imageData) { |
| 76 | + const texture = new THREE.Texture(imageData); |
| 77 | + texture.minFilter = THREE.NearestFilter; |
| 78 | + texture.magFilter = THREE.NearestFilter; |
| 79 | + texture.generateMipmaps = false; |
| 80 | + texture.needsUpdate = true; |
| 81 | + return texture; |
| 82 | +} |
| 83 | + |
| 84 | +function drawImageData({ imageData, filterData, canvas }) { |
| 85 | + const { width, height } = imageData; |
| 86 | + const halfWidth = width / 2; |
| 87 | + const halfHeight = height / 2; |
| 88 | + |
| 89 | + const renderer = new THREE.WebGLRenderer({ |
| 90 | + canvas, |
| 91 | + antialias: false, |
| 92 | + alpha: false, |
| 93 | + }); |
| 94 | + |
| 95 | + const scene = new THREE.Scene(); |
| 96 | + const camera = new THREE.OrthographicCamera( |
| 97 | + -halfWidth, halfWidth, halfHeight, -halfHeight, 1, 1000 |
| 98 | + ); |
| 99 | + camera.position.z = 10; |
| 100 | + scene.add(camera); |
| 101 | + |
| 102 | + const geometry = new THREE.PlaneGeometry(width, height); |
| 103 | + const material = new THREE.ShaderMaterial({ |
| 104 | + uniforms: { |
| 105 | + uImage: { value: createTexture(imageData) }, |
| 106 | + uFilter: { value: createTexture(filterData) }, |
| 107 | + }, |
| 108 | + vertexShader, |
| 109 | + fragmentShader, |
| 110 | + }); |
| 111 | + |
| 112 | + const mesh = new THREE.Mesh(geometry, material); |
| 113 | + scene.add(mesh); |
| 114 | + |
| 115 | + renderer.render(scene, camera); |
| 116 | +} |
| 117 | + |
| 118 | +function calculateIndex(r, g, b) { |
| 119 | + const x = r + (b % 16) * 256; |
| 120 | + const y = g + Math.floor(b / 16) * 256; |
| 121 | + return y * 256 * 16 + x; |
| 122 | +} |
| 123 | + |
| 124 | +class Application { |
| 125 | + filterData = null; |
| 126 | + |
| 127 | + async selectFilter(event) { |
| 128 | + const file = event.target.files[0]; |
| 129 | + if (!file) { |
| 130 | + return; |
| 131 | + } |
| 132 | + |
| 133 | + const dataURL = await readFileAsDataURL(file); |
| 134 | + const image = await createImageFromAsDataURL(dataURL); |
| 135 | + |
| 136 | + const filterCanvas = this.$refs.filterCanvas; |
| 137 | + filterCanvas.width = image.width; |
| 138 | + filterCanvas.height = image.height; |
| 139 | + |
| 140 | + drawImage({ image, canvas: filterCanvas }); |
| 141 | + |
| 142 | + this.filterData = getImageData(filterCanvas); |
| 143 | + } |
| 144 | + |
| 145 | + async selectImage(event) { |
| 146 | + if (!this.filterData) { |
| 147 | + alert('Please select a filter first.'); |
| 148 | + return; |
| 149 | + } |
| 150 | + |
| 151 | + const file = event.target.files[0]; |
| 152 | + if (!file) { |
| 153 | + return; |
| 154 | + } |
| 155 | + |
| 156 | + const dataURL = await readFileAsDataURL(file); |
| 157 | + const image = await createImageFromAsDataURL(dataURL); |
| 158 | + |
| 159 | + const sourceCanvas = this.$refs.sourceCanvas; |
| 160 | + sourceCanvas.width = image.width; |
| 161 | + sourceCanvas.height = image.height; |
| 162 | + |
| 163 | + const targetCanvas = this.$refs.targetCanvas; |
| 164 | + targetCanvas.width = image.width; |
| 165 | + targetCanvas.height = image.height; |
| 166 | + |
| 167 | + drawImage({ image, canvas: sourceCanvas }); |
| 168 | + |
| 169 | + const imageData = getImageData(sourceCanvas); |
| 170 | + |
| 171 | + drawImageData({ |
| 172 | + imageData, |
| 173 | + filterData: this.filterData, |
| 174 | + canvas: targetCanvas, |
| 175 | + }); |
| 176 | + } |
| 177 | +} |
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