Product Illustrator

Product Illustrator

Generate product images from CAD source files for marketing, ecommerce listings, instruction manuals, and packaging. Bridges parametric CAD (CadQuery, OpenSCAD) with AI image generation (ComfyUI) for production-quality visual assets.

Operating context

This skill serves product teams producing visual assets for ecommerce storefronts, marketing sites, and instruction manuals. It is designed for workflows where products originate as parametric CAD models (3D-printed goods, manufactured parts, consumer products) and need polished imagery for customer-facing channels.

Typical roles that interact with this pipeline:

Infrastructure

Configure the following environment variables to connect to your rendering services:

ComfyUI endpoint: http://${COMFYUI_HOST}:${COMFYUI_PORT}

If CadQuery requires additional shared libraries, set LD_LIBRARY_PATH before running:

export LD_LIBRARY_PATH="${CAD_LIB_PATH}:$LD_LIBRARY_PATH"

CAD tools

Pipeline overview

CAD Source                  Rendering                    Enhancement
+----------------+         +------------------+         +------------------+
| CadQuery (.py) |  STL    | CadQuery render  |  PNG    | ComfyUI          |
| OpenSCAD (.scad)| -----> | or               | -----> | (style transfer,  |
| STL files      |         | Blender headless |         |  background,      |
+----------------+         +------------------+         |  enhancement)     |
                                                        +------------------+
                                                               |
                                                        +------+-------+
                                                        |              |
                                                   Marketing      Instruction
                                                   renders        manual images

Reading CAD files

CadQuery Python files (.py)

CadQuery scripts are parametric -- they define geometry through code. To understand a product:

1. Read the .py file to extract parameters (dimensions, tolerances, materials)
2. Identify the key components (frames, inserts, connectors, etc.)
3. Note the export calls (cq.exporters.export()) to find what STLs are generated

import cadquery as cq

# Read and render a CadQuery model
result = cq.Workplane("XY").box(100, 50, 10)

# Export STL for printing
cq.exporters.export(result, "output/part.stl")

# Export SVG for 2D illustration (orthographic views)
cq.exporters.export(result, "output/part_front.svg",
    opt={"projectionDir": (0, 0, 1)})  # Top view
cq.exporters.export(result, "output/part_side.svg",
    opt={"projectionDir": (1, 0, 0)})  # Side view
cq.exporters.export(result, "output/part_iso.svg",
    opt={"projectionDir": (1, 1, 1)})  # Isometric view

OpenSCAD files (.scad)

If given a .scad file, read it to understand the geometry. Key syntax:

// Primitives
cube([width, depth, height]);
sphere(r=radius);
cylinder(h=height, r=radius);

// Transforms
translate([x, y, z]) { ... }
rotate([rx, ry, rz]) { ... }
scale([sx, sy, sz]) { ... }

// Boolean operations
union() { ... }        // Combine shapes
difference() { ... }   // Subtract second from first
intersection() { ... } // Keep only overlap

// Parametric
module part_name(param1, param2) { ... }

Since OpenSCAD binary isn't installed, convert to CadQuery for rendering, or describe the geometry for ComfyUI prompt generation.

STL files

STL files are mesh data -- they can't be read as source code. For STL-only products:

• Note the filename convention to understand what the part is
• Use CadQuery's STL import: cq.importers.importStep("part.stl")
• Or render with a headless tool and pass to ComfyUI

Rendering with CadQuery

Orthographic views (for instruction manuals)

import cadquery as cq

model = cq.importers.importStep("product.step")
# or build from CadQuery script

# Front view
cq.exporters.export(model, "front.svg",
    opt={"projectionDir": (0, -1, 0), "width": 800, "height": 600})

# Top view
cq.exporters.export(model, "top.svg",
    opt={"projectionDir": (0, 0, 1), "width": 800, "height": 600})

# Isometric (exploded or assembled)
cq.exporters.export(model, "iso.svg",
    opt={"projectionDir": (1, -1, 1), "width": 800, "height": 600})

Exploded views (for assembly instructions)

import cadquery as cq

# Render each part offset along the assembly axis
frame = build_frame()
insert = build_insert().translate((0, 0, 30))   # Offset upward
connector = build_connector().translate((0, 0, 60))

# Export each part as a separate SVG layer, or combine
assembly = cq.Assembly()
assembly.add(frame, name="frame")
assembly.add(insert, name="insert", loc=cq.Location((0, 0, 30)))
assembly.add(connector, name="connector", loc=cq.Location((0, 0, 60)))

ComfyUI enhancement

After generating base renders from CAD, use ComfyUI to produce polished marketing images.

ComfyUI endpoint: http://${COMFYUI_HOST}:${COMFYUI_PORT}

See the concept-art skill for full ComfyUI API details. The key differences for product illustration:

Marketing renders

Transform CAD renders into photorealistic product shots:

Prompt structure:
"professional product photography, {product description},
{material/finish}, studio lighting, white background,
soft shadows, high-key lighting, commercial photography,
8k, sharp focus, {angle}"

Example prompts by product type:

3D-printed decorative product:

"professional product photography, geometric decorative wall panel,
intricate lattice pattern, matte PLA finish, warm studio lighting,
clean white background, soft shadows, lifestyle interior setting,
modern minimalist decor, commercial product shot"

Product on white background (for Etsy/ecommerce):

"product photography on pure white background, {product},
even studio lighting, no shadows, isolated product,
ecommerce listing style, clean, sharp, professional"

Lifestyle context (for marketing sites):

"interior design photography, {product} mounted on modern wall,
living room setting, natural window light, scandinavian style,
lifestyle product photography, editorial quality"

Instruction manual illustrations

For clean technical illustrations:

"technical illustration, {assembly step description},
clean line art, instruction manual style, numbered callouts,
white background, clear and simple, isometric view,
assembly diagram, no shading"

Or enhance CAD SVG exports:

"clean technical diagram, product assembly illustration,
exploded view, {parts description}, minimal style,
numbered parts, clear arrows showing assembly direction,
instruction booklet quality"

Image types and specifications

Etsy / Ecommerce listings

Etsy allows up to 10 images per listing. Recommended set:

1. Hero shot (product on white)
2. Lifestyle context (product in room)
3. Detail/texture close-up
4. Scale reference
5. Color variants (if applicable)
6. Assembly/usage illustration
7. Packaging/unboxing

Instruction manual images

Marketing site renders

Workflow by deliverable

Ecommerce listing images

1. Read the CAD source to understand the product geometry and variants
2. Generate orthographic renders from CadQuery for accurate product views
3. Enhance with ComfyUI for white-background studio shots
4. Generate lifestyle images with ComfyUI for context shots
5. Create detail crops focusing on textures, patterns, material finish
6. Confirm with operator before using for listings

Assembly instructions

1. Read the CAD source and identify all parts and assembly sequence
2. Generate exploded views showing parts separated along assembly axis
3. Render each assembly step with relevant parts highlighted
4. Add callout annotations (part numbers, arrow directions)
5. Export as SVG or clean PNG for print and digital manual use
6. Number steps sequentially with clear "before" and "after" states

Marketing site renders

1. Read the CAD source to understand the product
2. Generate hero renders from the best angles
3. Use ComfyUI to create photorealistic renders with dramatic lighting
4. Create lifestyle contexts (product in real-world settings)
5. Generate multiple colorways/variants if applicable
6. Output at web-optimized sizes (WebP for web, PNG for print)

Naming conventions

output/
  {project}/
    product/
      ecommerce/
        listing_{product}_{variant}_{number}.png    -- Etsy/shop images
        lifestyle_{product}_{setting}_{number}.png  -- Context shots
      manual/
        step_{NN}_{description}.svg                 -- Assembly steps
        parts_list.svg                              -- Parts overview
        exploded_{view}.svg                         -- Exploded diagrams
      marketing/
        hero_{product}_{angle}_{number}.png         -- Hero banners
        grid_{product}_{variant}.png                -- Product grid tiles
        feature_{product}_{detail}.png              -- Feature callouts
      renders/
        ortho_{product}_{view}.svg                  -- Orthographic views from CAD
        iso_{product}.svg                           -- Isometric views from CAD

Use filename_prefix in ComfyUI's SaveImage node to route output automatically.

Sampler settings for product images

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