(() => { const fileInput = document.getElementById('file-input'); const dropZone = document.getElementById('drop-zone'); const dropCard = document.getElementById('drop-card'); const editorCard = document.getElementById('editor-card'); const canvas = document.getElementById('canvas'); const ctx = canvas.getContext('2d'); const aspectRow = document.getElementById('aspect-row'); const rotateLeftBtn = document.getElementById('rotate-left-btn'); const rotateRightBtn = document.getElementById('rotate-right-btn'); const presetRow = document.getElementById('preset-row'); const grainSlider = document.getElementById('grain'); const grainSizeSlider = document.getElementById('grain-size'); const grainColorToggle = document.getElementById('grain-color-toggle'); const vignetteSlider = document.getElementById('vignette'); const halationSlider = document.getElementById('halation'); const aberrationSlider = document.getElementById('aberration'); const dustSlider = document.getElementById('dust'); const rerollDustBtn = document.getElementById('reroll-dust'); const leakSlider = document.getElementById('leak'); const leakShapeRow = document.getElementById('leak-shape-row'); const rerollLeakBtn = document.getElementById('reroll-leak'); const addExposureBtn = document.getElementById('add-exposure-btn'); const removeExposureBtn = document.getElementById('remove-exposure-btn'); const exposureInput = document.getElementById('exposure-input'); const exposureControls = document.getElementById('exposure-controls'); const exposureBlend = document.getElementById('exposure-blend'); const exposureOpacity = document.getElementById('exposure-opacity'); const resetBtn = document.getElementById('reset-btn'); const newPhotoBtn = document.getElementById('new-photo-btn'); const downloadBtn = document.getElementById('download-btn'); const shareBtn = document.getElementById('share-btn'); const developBtn = document.getElementById('develop-btn'); const resultPanel = document.getElementById('result-panel'); // Offscreen canvases reused across renders so we're not allocating per frame. const source = document.createElement('canvas'); // original, rotated, uncropped const sourceCtx = source.getContext('2d'); const work = document.createElement('canvas'); const workCtx = work.getContext('2d'); const bloom = document.createElement('canvas'); const bloomCtx = bloom.getContext('2d'); const noiseCanvas = document.createElement('canvas'); const noiseCtx = noiseCanvas.getContext('2d'); const channelCanvas = document.createElement('canvas'); const channelCtx = channelCanvas.getContext('2d'); let originalImg = null; let exposureImg = null; const PRESETS = { none: { filter: 'none' }, // "Pick a vibe" presets rather than raw white-balance sliders, per // PROPOSAL.md — expressed as CSS filter strings applied at draw time. warm: { filter: 'sepia(0.6) saturate(1.8) hue-rotate(-15deg) contrast(1.1) brightness(1.05)' }, cool: { filter: 'saturate(1.9) hue-rotate(165deg) contrast(1.2) brightness(0.9)' }, faded: { filter: 'sepia(0.2) saturate(0.35) contrast(0.7) brightness(1.15)' }, polaroid: { filter: 'contrast(1.25) brightness(0.92) saturate(0.85) hue-rotate(6deg) sepia(0.18)' }, infrared: { filter: 'hue-rotate(275deg) saturate(2.2) contrast(1.3) brightness(1.1)' }, bw: { filter: 'grayscale(1) contrast(1.15) brightness(1.05)' }, }; const ASPECTS = { original: null, square: 1, portrait: 4 / 5, landscape: 16 / 9, }; const params = { rotation: 0, cropAspect: 'original', preset: 'none', grain: 0, grainSize: 40, grainColor: 'mono', vignette: 0, halation: 0, aberration: 0, dust: 0, dustSeed: Math.random(), leak: 0, leakShape: 'bloom', leakSeed: Math.random(), exposureBlend: 'screen', exposureOpacity: 50, }; // Small seeded PRNG so dust/scratch placement stays fixed across // slider tweaks and only changes on an explicit reroll. function mulberry32(seed) { let a = Math.floor(seed * 0xffffffff); return function () { a |= 0; a = (a + 0x6d2b79f5) | 0; let t = Math.imul(a ^ (a >>> 15), 1 | a); t = (t + Math.imul(t ^ (t >>> 7), 61 | t)) ^ t; return ((t ^ (t >>> 14)) >>> 0) / 4294967296; }; } function loadFile(file) { if (!file || !file.type.startsWith('image/')) return; const url = URL.createObjectURL(file); const img = new Image(); img.onload = () => { originalImg = img; URL.revokeObjectURL(url); dropCard.hidden = true; editorCard.hidden = false; resultPanel.hidden = true; resetParams(); rebuildSource(); render(); }; img.src = url; } function resetParams() { params.rotation = 0; params.cropAspect = 'original'; params.preset = 'none'; params.grain = 0; params.grainSize = 40; params.grainColor = 'mono'; params.vignette = 0; params.halation = 0; params.aberration = 0; params.dust = 0; params.dustSeed = Math.random(); params.leak = 0; params.leakShape = 'bloom'; params.leakSeed = Math.random(); exposureImg = null; params.exposureBlend = 'screen'; params.exposureOpacity = 50; grainSlider.value = 0; grainSizeSlider.value = 40; grainColorToggle.dataset.mode = 'mono'; grainColorToggle.textContent = 'grain: mono'; vignetteSlider.value = 0; halationSlider.value = 0; aberrationSlider.value = 0; dustSlider.value = 0; leakSlider.value = 0; exposureBlend.value = 'screen'; exposureOpacity.value = 50; exposureControls.hidden = true; addExposureBtn.hidden = false; removeExposureBtn.hidden = true; exposureInput.value = ''; updateValueLabels(); [...presetRow.children].forEach(b => b.classList.toggle('active', b.dataset.preset === 'none')); [...aspectRow.children].forEach(b => b.classList.toggle('active', b.dataset.aspect === 'original')); [...leakShapeRow.children].forEach(b => b.classList.toggle('active', b.dataset.shape === 'bloom')); } function updateValueLabels() { document.getElementById('grain-value').textContent = params.grain; document.getElementById('vignette-value').textContent = params.vignette; document.getElementById('halation-value').textContent = params.halation; document.getElementById('aberration-value').textContent = params.aberration; document.getElementById('dust-value').textContent = params.dust; document.getElementById('leak-value').textContent = params.leak; } // Rebuilds `source` (the rotated + cropped, but otherwise unedited, // base image) from originalImg. Only called when rotation, crop, or // the loaded image change — not on every effect-slider tweak — since // it's the one step that can't be recomputed from other canvases. function rebuildSource() { if (!originalImg) return; const rot = params.rotation; const iw = originalImg.naturalWidth; const ih = originalImg.naturalHeight; const swapped = rot === 90 || rot === 270; const rotatedW = swapped ? ih : iw; const rotatedH = swapped ? iw : ih; const rotated = document.createElement('canvas'); rotated.width = rotatedW; rotated.height = rotatedH; const rc = rotated.getContext('2d'); rc.save(); rc.translate(rotatedW / 2, rotatedH / 2); rc.rotate((rot * Math.PI) / 180); rc.drawImage(originalImg, -iw / 2, -ih / 2); rc.restore(); const targetAspect = ASPECTS[params.cropAspect]; let cropW = rotatedW; let cropH = rotatedH; let cropX = 0; let cropY = 0; if (targetAspect) { const currentAspect = rotatedW / rotatedH; if (currentAspect > targetAspect) { cropW = Math.round(rotatedH * targetAspect); cropX = Math.round((rotatedW - cropW) / 2); } else { cropH = Math.round(rotatedW / targetAspect); cropY = Math.round((rotatedH - cropH) / 2); } } // Cap so a raw phone photo doesn't choke canvas ops. const maxDim = 2400; let outW = cropW; let outH = cropH; if (Math.max(outW, outH) > maxDim) { const scale = maxDim / Math.max(outW, outH); outW = Math.round(outW * scale); outH = Math.round(outH * scale); } source.width = outW; source.height = outH; sourceCtx.clearRect(0, 0, outW, outH); sourceCtx.drawImage(rotated, cropX, cropY, cropW, cropH, 0, 0, outW, outH); canvas.width = outW; canvas.height = outH; work.width = outW; work.height = outH; bloom.width = outW; bloom.height = outH; channelCanvas.width = outW; channelCanvas.height = outH; } // Recomputes the full stack from `source` every time — never chains // operations onto already-processed pixels — so dragging any slider // back to 0 reproduces the source exactly. function render() { if (!originalImg) return; const w = canvas.width; const h = canvas.height; workCtx.filter = PRESETS[params.preset].filter; workCtx.globalCompositeOperation = 'source-over'; workCtx.clearRect(0, 0, w, h); workCtx.drawImage(source, 0, 0); workCtx.filter = 'none'; if (exposureImg) applyDoubleExposure(w, h); if (params.halation > 0) applyHalation(w, h); if (params.aberration > 0) applyChromaticAberration(w, h); if (params.vignette > 0) applyVignette(w, h); if (params.leak > 0) applyLightLeak(w, h); if (params.dust > 0) applyDustScratches(w, h); if (params.grain > 0) applyGrain(w, h); ctx.clearRect(0, 0, w, h); ctx.drawImage(work, 0, 0); } // Blends a second uploaded photo in, cover-fit to the canvas — the // literal "double exposure" film trick. function applyDoubleExposure(w, h) { const iw = exposureImg.naturalWidth; const ih = exposureImg.naturalHeight; const scale = Math.max(w / iw, h / ih); const dw = iw * scale; const dh = ih * scale; const dx = (w - dw) / 2; const dy = (h - dh) / 2; workCtx.save(); workCtx.globalCompositeOperation = params.exposureBlend; workCtx.globalAlpha = params.exposureOpacity / 100; workCtx.drawImage(exposureImg, dx, dy, dw, dh); workCtx.restore(); } // Bloom around bright areas: blur a thresholded bright-pass and screen // it back over the original. function applyHalation(w, h) { bloomCtx.clearRect(0, 0, w, h); bloomCtx.filter = 'brightness(180%) contrast(400%) saturate(120%)'; bloomCtx.drawImage(work, 0, 0); bloomCtx.filter = 'none'; const blurPx = Math.max(4, Math.round(Math.min(w, h) * 0.02)); bloomCtx.filter = `blur(${blurPx}px)`; bloomCtx.drawImage(bloom, 0, 0); bloomCtx.filter = 'none'; workCtx.save(); workCtx.globalCompositeOperation = 'screen'; workCtx.globalAlpha = (params.halation / 100) * 0.85; workCtx.drawImage(bloom, 0, 0); workCtx.restore(); } // Isolates a single color channel by multiplying against a solid // pure-channel fill — cheap alternative to a per-pixel channel split. function channelLayer(colorRgb) { channelCtx.clearRect(0, 0, channelCanvas.width, channelCanvas.height); channelCtx.globalCompositeOperation = 'source-over'; channelCtx.drawImage(work, 0, 0); channelCtx.globalCompositeOperation = 'multiply'; channelCtx.fillStyle = colorRgb; channelCtx.fillRect(0, 0, channelCanvas.width, channelCanvas.height); return channelCanvas; } // Cheap "lens fringing" look: shift isolated red/blue channel layers in // opposite directions and screen them back over the full-color image. // Not a physically accurate simulation, just a stylized fringe. function applyChromaticAberration(w, h) { const amount = params.aberration / 100; const shift = Math.max(1, Math.round(amount * Math.max(w, h) * 0.015)); const redSnapshot = document.createElement('canvas'); redSnapshot.width = w; redSnapshot.height = h; redSnapshot.getContext('2d').drawImage(channelLayer('rgb(255,0,0)'), 0, 0); const blueSnapshot = document.createElement('canvas'); blueSnapshot.width = w; blueSnapshot.height = h; blueSnapshot.getContext('2d').drawImage(channelLayer('rgb(0,0,255)'), 0, 0); workCtx.save(); workCtx.globalCompositeOperation = 'screen'; workCtx.globalAlpha = 0.55; workCtx.drawImage(redSnapshot, -shift, 0); workCtx.drawImage(blueSnapshot, shift, 0); workCtx.restore(); } function applyVignette(w, h) { const amount = params.vignette / 100; const cx = w / 2; const cy = h / 2; const outerR = Math.hypot(cx, cy); const grad = workCtx.createRadialGradient(cx, cy, outerR * 0.35, cx, cy, outerR); grad.addColorStop(0, 'rgba(0,0,0,0)'); grad.addColorStop(1, `rgba(0,0,0,${amount * 0.85})`); workCtx.save(); workCtx.globalCompositeOperation = 'multiply'; workCtx.fillStyle = grad; workCtx.fillRect(0, 0, w, h); workCtx.restore(); } // Three shapes off one seed so repeat use doesn't look identical, and // no pre-baked PNG assets are needed — it's all procedural gradients. function applyLightLeak(w, h) { const seed = params.leakSeed; const alpha = params.leak / 100; const hue = 25 + seed * 30; // warm amber/red range workCtx.save(); workCtx.globalCompositeOperation = 'screen'; if (params.leakShape === 'streak') { const angle = seed * Math.PI * 2; const cx = w * (0.2 + seed * 0.6); const cy = h * (0.2 + (1 - seed) * 0.6); const length = Math.max(w, h) * 1.4; const x0 = cx - Math.cos(angle) * length / 2; const y0 = cy - Math.sin(angle) * length / 2; const x1 = cx + Math.cos(angle) * length / 2; const y1 = cy + Math.sin(angle) * length / 2; const grad = workCtx.createLinearGradient(x0, y0, x1, y1); grad.addColorStop(0, 'hsla(0, 0%, 0%, 0)'); grad.addColorStop(0.5, `hsla(${hue}, 90%, 60%, ${alpha * 0.75})`); grad.addColorStop(1, 'hsla(0, 0%, 0%, 0)'); workCtx.fillStyle = grad; workCtx.fillRect(0, 0, w, h); } else if (params.leakShape === 'corner') { const corners = [[0, 0], [w, 0], [0, h], [w, h]]; const [cx, cy] = corners[Math.floor(seed * 4) % 4]; const radius = Math.max(w, h) * (0.55 + seed * 0.3); const grad = workCtx.createRadialGradient(cx, cy, 0, cx, cy, radius); grad.addColorStop(0, `hsla(${hue}, 90%, 60%, ${alpha * 0.9})`); grad.addColorStop(1, 'hsla(0, 0%, 0%, 0)'); workCtx.fillStyle = grad; workCtx.fillRect(0, 0, w, h); } else { // bloom — a blob placed near a randomized edge point const angle = seed * Math.PI * 2; const edgeX = w / 2 + Math.cos(angle) * w * 0.7; const edgeY = h / 2 + Math.sin(angle) * h * 0.7; const radius = Math.max(w, h) * (0.5 + seed * 0.3); const grad = workCtx.createRadialGradient(edgeX, edgeY, 0, edgeX, edgeY, radius); grad.addColorStop(0, `hsla(${hue}, 90%, 60%, ${alpha * 0.9})`); grad.addColorStop(0.5, `hsla(${hue + 10}, 90%, 55%, ${alpha * 0.35})`); grad.addColorStop(1, 'hsla(0, 0%, 0%, 0)'); workCtx.fillStyle = grad; workCtx.fillRect(0, 0, w, h); } workCtx.restore(); } // Random hairline scratches + specks of dust, regenerated only on // reroll (seeded), not on every slider tweak. function applyDustScratches(w, h) { const amount = params.dust / 100; const rng = mulberry32(params.dustSeed); workCtx.save(); workCtx.globalCompositeOperation = 'screen'; const scratchCount = Math.round(amount * 12); for (let i = 0; i < scratchCount; i++) { workCtx.strokeStyle = `rgba(255,255,255,${0.05 + rng() * 0.15})`; workCtx.lineWidth = 1; const x = rng() * w; workCtx.beginPath(); workCtx.moveTo(x, 0); workCtx.lineTo(x + (rng() - 0.5) * 24, h); workCtx.stroke(); } const dustCount = Math.round(amount * 90); for (let i = 0; i < dustCount; i++) { workCtx.fillStyle = `rgba(255,255,255,${0.2 + rng() * 0.5})`; const x = rng() * w; const y = rng() * h; const r = 0.5 + rng() * 1.5; workCtx.beginPath(); workCtx.arc(x, y, r, 0, Math.PI * 2); workCtx.fill(); } workCtx.restore(); } function applyGrain(w, h) { // Noise is generated at reduced resolution and scaled up — a // per-pixel random overlay at full phone-photo resolution is // needlessly slow and reads no differently once blended in. // grainSize maps a bigger divisor to coarser, more visible grain. const divisor = 1.5 + (params.grainSize / 100) * 8.5; const nw = Math.max(1, Math.round(w / divisor)); const nh = Math.max(1, Math.round(h / divisor)); noiseCanvas.width = nw; noiseCanvas.height = nh; const imgData = noiseCtx.createImageData(nw, nh); const d = imgData.data; if (params.grainColor === 'color') { for (let i = 0; i < d.length; i += 4) { d[i] = Math.random() * 255; d[i + 1] = Math.random() * 255; d[i + 2] = Math.random() * 255; d[i + 3] = 255; } } else { for (let i = 0; i < d.length; i += 4) { const v = Math.random() * 255; d[i] = v; d[i + 1] = v; d[i + 2] = v; d[i + 3] = 255; } } noiseCtx.putImageData(imgData, 0, 0); workCtx.save(); workCtx.globalCompositeOperation = 'overlay'; workCtx.globalAlpha = (params.grain / 100) * 0.6; workCtx.imageSmoothingEnabled = false; workCtx.drawImage(noiseCanvas, 0, 0, w, h); workCtx.restore(); } function showResult(html, isError) { resultPanel.innerHTML = html; resultPanel.classList.toggle('error', !!isError); resultPanel.hidden = false; } function canvasToBlob() { return new Promise(resolve => canvas.toBlob(resolve, 'image/jpeg', 0.92)); } async function upload(delayed) { const btn = delayed ? developBtn : shareBtn; btn.disabled = true; showResult('uploading…'); try { const blob = await canvasToBlob(); const res = await fetch(`/api/upload?delayed=${delayed}`, { method: 'POST', headers: { 'Content-Type': 'image/jpeg' }, body: blob, }); if (!res.ok) { const body = await res.json().catch(() => ({})); throw new Error(body.error || `upload failed (${res.status})`); } const data = await res.json(); const link = `${location.origin}${data.url}`; if (delayed) { showResult( `sent to develop. link: ${link}
` + `ready sometime in the next ${data.developInHours} hours — ` + `same link resolves once it's done.` ); } else { showResult(`share link: ${link}`); } } catch (err) { showResult(err.message || 'something went wrong', true); } finally { btn.disabled = false; } } fileInput.addEventListener('change', () => loadFile(fileInput.files[0])); ['dragover', 'dragenter'].forEach(evt => dropZone.addEventListener(evt, e => { e.preventDefault(); dropZone.classList.add('drag-over'); }) ); ['dragleave', 'dragend', 'drop'].forEach(evt => dropZone.addEventListener(evt, () => dropZone.classList.remove('drag-over')) ); dropZone.addEventListener('drop', e => { e.preventDefault(); loadFile(e.dataTransfer.files[0]); }); [...aspectRow.children].forEach(btn => { btn.addEventListener('click', () => { params.cropAspect = btn.dataset.aspect; [...aspectRow.children].forEach(b => b.classList.toggle('active', b === btn)); rebuildSource(); render(); }); }); rotateLeftBtn.addEventListener('click', () => { params.rotation = (params.rotation + 270) % 360; rebuildSource(); render(); }); rotateRightBtn.addEventListener('click', () => { params.rotation = (params.rotation + 90) % 360; rebuildSource(); render(); }); [...presetRow.children].forEach(btn => { btn.addEventListener('click', () => { params.preset = btn.dataset.preset; [...presetRow.children].forEach(b => b.classList.toggle('active', b === btn)); render(); }); }); [...leakShapeRow.children].forEach(btn => { btn.addEventListener('click', () => { params.leakShape = btn.dataset.shape; [...leakShapeRow.children].forEach(b => b.classList.toggle('active', b === btn)); render(); }); }); grainSlider.addEventListener('input', () => { params.grain = Number(grainSlider.value); updateValueLabels(); render(); }); grainSizeSlider.addEventListener('input', () => { params.grainSize = Number(grainSizeSlider.value); render(); }); grainColorToggle.addEventListener('click', () => { params.grainColor = params.grainColor === 'mono' ? 'color' : 'mono'; grainColorToggle.dataset.mode = params.grainColor; grainColorToggle.textContent = `grain: ${params.grainColor}`; render(); }); vignetteSlider.addEventListener('input', () => { params.vignette = Number(vignetteSlider.value); updateValueLabels(); render(); }); halationSlider.addEventListener('input', () => { params.halation = Number(halationSlider.value); updateValueLabels(); render(); }); aberrationSlider.addEventListener('input', () => { params.aberration = Number(aberrationSlider.value); updateValueLabels(); render(); }); dustSlider.addEventListener('input', () => { params.dust = Number(dustSlider.value); updateValueLabels(); render(); }); rerollDustBtn.addEventListener('click', () => { params.dustSeed = Math.random(); render(); }); leakSlider.addEventListener('input', () => { params.leak = Number(leakSlider.value); updateValueLabels(); render(); }); rerollLeakBtn.addEventListener('click', () => { params.leakSeed = Math.random(); render(); }); addExposureBtn.addEventListener('click', () => exposureInput.click()); exposureInput.addEventListener('change', () => { const file = exposureInput.files[0]; if (!file || !file.type.startsWith('image/')) return; const url = URL.createObjectURL(file); const img = new Image(); img.onload = () => { exposureImg = img; URL.revokeObjectURL(url); addExposureBtn.hidden = true; removeExposureBtn.hidden = false; exposureControls.hidden = false; render(); }; img.src = url; }); removeExposureBtn.addEventListener('click', () => { exposureImg = null; exposureInput.value = ''; addExposureBtn.hidden = false; removeExposureBtn.hidden = true; exposureControls.hidden = true; render(); }); exposureBlend.addEventListener('change', () => { params.exposureBlend = exposureBlend.value; render(); }); exposureOpacity.addEventListener('input', () => { params.exposureOpacity = Number(exposureOpacity.value); render(); }); resetBtn.addEventListener('click', () => { resetParams(); rebuildSource(); render(); }); newPhotoBtn.addEventListener('click', () => { originalImg = null; exposureImg = null; fileInput.value = ''; editorCard.hidden = true; dropCard.hidden = false; resultPanel.hidden = true; }); downloadBtn.addEventListener('click', async () => { const blob = await canvasToBlob(); const url = URL.createObjectURL(blob); const a = document.createElement('a'); a.href = url; a.download = `latent-${Date.now()}.jpg`; a.click(); URL.revokeObjectURL(url); }); shareBtn.addEventListener('click', () => upload(false)); developBtn.addEventListener('click', () => upload(true)); })();