CAD Designer

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\n\n \n \n\n`;\n}\n\nexport default app.fetch;\n","label",[128],"6bea9cea-0507-11f1-805e-42dde27851f2","README.md","6bea9d80-0507-11f1-805e-42dde27851f2",2,["D",1770566485857],"# CAD Designer — Visual Feedback 3D Design Tool\n\n## What This Is\n\nA tool for LLMs (specifically Claude on claude.ai) to design 3D printable models using **OpenSCAD** with a **visual feedback loop**. The key insight: LLMs can't do spatial reasoning blind. They need to render → see → fix → repeat.\n\n## The Visual Feedback Loop (CRITICAL)\n\nThis is the core workflow that makes LLM-driven CAD actually work. Without it, you're guessing and will get geometry wrong every time.\n\n### Prerequisites (Claude's Linux computer)\n\nThese tools are available in Claude's container environment:\n\n```bash\n# Install OpenSCAD (may already be installed)\napt-get update && apt-get install -y openscad xvfb\n\n# Verify\nxvfb-run -a openscad --version\n```\n\n### The Loop\n\n```\n1. WRITE → Create/edit a .scad file\n2. RENDER → xvfb-run -a openscad -o render.png --imgsize=800,600 \\\n --camera=200,200,150,0,0,40 model.scad\n3. VIEW → Use the `view` tool on render.png — YOU CAN SEE THE IMAGE\n4. ASSESS → What's wrong? Too flat? Wrong orientation? Missing features?\n5. FIX → Edit the .scad file\n6. GOTO 2\n```\n\n### Camera Tips\n\nThe `--camera` flag takes: `eyeX,eyeY,eyeZ,centerX,centerY,centerZ`\n\n```bash\n# Isometric (best for first look)\n--camera=200,200,150,0,0,40\n\n# Front view\n--camera=0,250,40,0,0,40\n\n# Top down \n--camera=0,1,300,0,0,30\n\n# Bottom up (to see underside)\n--camera=0,1,-300,0,0,20\n\n# Orthographic projection (engineering drawings)\n--camera=100,0,40,0,0,40 --projection=o\n```\n\nIf the model is too big/small in frame, adjust the eye distance (first 3 numbers).\n\n### Cross-Section Trick\n\nTo see internal geometry (cavities, bores, channels), cut the model in half:\n\n```openscad\ndifference() {\n // Your full model here\n my_model();\n \n // Cut away half (adjust plane as needed)\n translate([0, -200, -10]) cube([400, 400, 200]); // removes Y > 0\n}\n```\n\nThen render from the cut side to see inside.\n\n### Multi-Angle Verification\n\nAlways render at least 3 views:\n- **Isometric** — overall shape check\n- **Front/Side** — proportions, symmetry\n- **Cross-section** — internal geometry verification\n\n```bash\nxvfb-run -a openscad -o iso.png --imgsize=800,600 --camera=200,200,150,0,0,40 model.scad\nxvfb-run -a openscad -o front.png --imgsize=800,600 --camera=0,250,40,0,0,40 model.scad\nxvfb-run -a openscad -o section.png --imgsize=800,600 --camera=200,0,40,0,0,40 section.scad\n```\n\n## Why OpenSCAD (Not JSCAD)\n\n- **CLI rendering**: `openscad -o file.png` works headless with xvfb. JSCAD has no CLI renderer.\n- **Visual feedback**: The whole point is render → view → fix. JSCAD can only output geometry data, not images.\n- **Simpler syntax**: OpenSCAD's declarative style is easier for LLMs than JSCAD's imperative JS.\n- **Cross-sections**: OpenSCAD's `difference()` with a cutting plane lets you see inside models.\n- **Well-documented**: OpenSCAD has extensive docs and examples the LLM already knows.\n\n## OpenSCAD Cheat Sheet\n\n```openscad\n// Primitives\ncube([x, y, z]); // box\ncube([x, y, z], center=true); // centered box\ncylinder(r=10, h=20); // cylinder\ncylinder(r1=10, r2=5, h=20); // cone/taper\nsphere(r=10); // sphere\n\n// Transforms\ntranslate([x, y, z]) child();\nrotate([rx, ry, rz]) child();\nscale([sx, sy, sz]) child();\n\n// Booleans (THE KEY OPERATIONS)\nunion() { a(); b(); } // combine\ndifference() { a(); b(); } // a minus b\nintersection() { a(); b(); } // overlap only\n\n// Hull (convex hull — great for organic shapes)\nhull() { a(); b(); }\n\n// Loops\nfor (i = [0:4]) translate([i*10, 0, 0]) cube(5);\n\n// Modules (reusable parts)\nmodule my_part(size=10) {\n difference() {\n cube(size);\n sphere(r=size*0.6);\n }\n}\n\n// Resolution\n$fn = 64; // smooth curves (put at top of file)\n```\n\n## Common Pitfalls for LLMs\n\n1. **Threads on the outside**: When making internal threads (female), you SUBTRACT rings slightly larger than the bore. The grooves go INTO the wall, not out.\n\n2. **Orientation confusion**: Always define your Z-axis convention upfront. For 3D printing: Z = up, build plate is Z=0.\n\n3. **Forgetting to look**: ALWAYS render and view before declaring something done. You WILL get geometry wrong on the first try.\n\n4. **Camera too close**: Start with eye distances of 200+. If you see a wall of color, zoom out.\n\n5. **Flat chambers**: If you want a cone/pyramid shape, make sure height > base radius. Otherwise it looks like a disc.\n\n6. **Overcomplicating**: Start with the simplest possible shape. A manifold is just cylinders entering a hollow cone. Don't add channels, hulls, and complex merging unless actually needed.\n\n## Val Structure\n\n```\nmain.ts — HTTP server: viewer page + design API\ndesigns/ — OpenSCAD design files \n bottleSplitter.scad — 3-way bottle manifold\nREADME.md — This file (YOU ARE HERE)\n```\n\n## Design API\n\n```\nGET / → viewer page (Three.js + OpenSCAD WASM)\nGET /api/designs → list all designs\nGET /api/designs/:id → get design SCAD code \nPOST /api/designs/:id → save design { name, scad }\n```\n\n## Research Background\n\nThis approach is based on CADCodeVerify (ICLR 2025) which showed that LLMs need visual feedback loops for CAD:\n- Render the model\n- Vision model inspects the render \n- Provides corrective feedback\n- Iterate until correct\n\nOur implementation uses OpenSCAD CLI + xvfb for rendering and Claude's `view` tool for visual inspection. It's the same principle, just using tools already available in the environment.\n\n## For the Next Claude\n\nIf you're picking this up:\n\n1. **Install first**: `apt-get install -y openscad xvfb` (may already be there)\n2. **Test the loop**: Write a cube.scad, render it, view it. Make sure you can see images.\n3. **Read the designs/**: See what exists already\n4. **Iterate visually**: Never commit a design you haven't rendered and viewed from multiple angles\n5. **Cross-section complex parts**: If there's internal geometry, cut it open and look inside\n6. **Keep it simple**: Most printable objects are just cylinders, cubes, and cones with boolean operations\n",[139],"719c43aa-0507-11f1-9bdb-42dde27851f2",["D",1770566495410],[27],"pulls","branches","forks","envVars",{"_155":58,"_157":58},"connections",{"_155":58,"_156":58},"count","unfilledCount","emptyCount",{"_40":145,"_31":27,"_29":30,"_130":-5,"_38":39,"_37":14,"_132":119,"_35":168,"_13":58,"_32":33,"_34":-5,"_23":24,"_136":-5,"_162":169,"_26":170},{"_40":138,"_31":139,"_29":140,"_130":-5,"_38":39,"_37":141,"_132":119,"_35":165,"_13":58,"_32":20,"_34":143,"_23":24,"_136":-5,"_162":166,"_26":167},{"_40":127,"_31":128,"_29":129,"_130":-5,"_38":39,"_37":131,"_132":24,"_35":161,"_13":58,"_32":134,"_34":135,"_23":24,"_136":-5,"_162":163,"_26":164},["D",1770566386787],"children",[],[128],["D",1770566485857],[],[139],["D",1770566495410],[],[27],["D",1770566327207],{"_92":91,"_100":96},{"_92":91,"_93":94,"_95":96,"_18":52,"_97":98,"_99":24},{"_13":81,"_31":82,"_40":39,"_83":41,"_84":-5,"_85":-5,"_86":-5,"_87":-5,"_88":-5,"_89":42,"_90":91},"ctx",{"_74":-5,"_121":208,"_209":210,"_211":212,"_213":24,"_214":24,"_215":24,"_216":119,"_217":-5,"_218":-7,"_219":-7,"_220":58,"_221":24,"_222":24,"_223":-5,"_224":24,"_225":24,"_226":24,"_227":-5},"ENV",{"_179":180,"_181":182,"_183":82,"_184":185,"_186":187,"_188":189,"_190":191,"_192":193,"_194":195,"_196":197,"_198":199,"_200":201,"_202":203,"_204":205,"_206":207},"REACT_APP_SENTRY_DSN","https://586020d86f05489db63a554690acf1e9@o1398359.ingest.sentry.io/6724499","RENDER_GIT_COMMIT","e87eb04e707cf64e7e532c8e8ec395f209e17f15","RENDER_GIT_BRANCH","POSTHOG_API_TOKEN","phc_nmoyuAkStEZuUp69rYlg1DZgrIt19Gx0Y4Hwf8tGgJP","POSTHOG_API_HOST","https://wart.val.town","WEB_API_TEMPLATE","https://{val}.web.val.run","APP_URL","https://www.val.town","MODULE_URL","https://esm.town","VANITY_WEB_API_TEMPLATE","https://{label}.val.run/","DENOLS_URL","https://lsp.val.town","NODE_ENV","production","CLOUDFLARE_TURNSTILE_SITE_KEY","0x4AAAAAACtaIZJH7s9rBMZ6","GOOGLE_CLIENT_ID","875989696899-jtsqkhlbdv5jrlsk8631p7ipjg3c6o62.apps.googleusercontent.com","STRIPE_PUBLISHABLE_KEY","pk_live_51N2zvWEpZTTLipIkVEwXrUG9AT0yeOOEYxszarZT1jpsZV58Ly6wlg3SltZpHN26CUalOBmUSY7adQRQiSkCZz2500qSXNkf8Y","API_URL","https://api.val.town",[],"preferencesKeybindings","default","preferencesTheme","light","preferencesFixers","preferencesCopilot","preferencesSelectionAi","preferencesCloseBrackets","preferencesChatPanelState","preferencesDprint","preferencesDenofmt","notificationCount","flagDenols","isBusinessOrgMember","businessOrgHandle","isBusinessOrgAdmin","isHigherTownieTier","navCollapsed","currentOrgId"]

◆ CAD DESIGNER — OpenSCAD

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