shared/references/advertising-manipulation.md

# Advertising Manipulation

Treat manipulation as a physics, geometry, and integration problem before spectacle

## Manipulation types

Support

- compositing
- object replacement
- scale manipulation
- perspective matching
- scene extension
- product insertion
- object isolation
- relighting
- color matching
- miniature scenes
- oversized objects
- surreal combinations
- foreground interaction
- environmental interaction

## Build a local physics model

Before generating or editing, define

- camera height and orientation
- horizon or perspective behavior
- key light direction and apparent size
- receiving surfaces
- contact points
- major reflective surfaces
- material classes
- atmospheric depth

Every inserted or generated element should obey that model unless the concept explicitly makes one property impossible

## Believability checks

### Perspective
Match horizon, vanishing behavior, camera height, and foreshortening

### Scale
Use environmental evidence so intentional scale reads as intentional

### Contact
Objects touching a surface need credible occlusion, compression, contact shadow, reflection, or bounce light as appropriate

### Cast shadow
Check direction, penumbra, density, receiving geometry, and distance from the caster

### Reflection
Reflections must correspond to the nearby environment, surface roughness, object orientation, and viewing angle

### Refraction and transparency
Glass and transparent materials must distort or transmit the background consistently with thickness and curvature

### Material
Preserve roughness, gloss, metallic response, translucency, fabric behavior, skin, print, liquid, and coating character

### Depth
Match atmospheric contrast, sharpness, blur, scale, and occlusion order

### Edge integration
Avoid cutout halos, mismatched sharpness, unnatural edge contrast, and missing color spill

### Environmental response
Wet scenes should affect contact, reflections, and nearby surfaces

Dusty, foggy, bright, colored, or reflective environments should leave believable evidence on the inserted object

## Impossible photography

The concept may violate global reality while preserving local coherence

An oversized perfume bottle in a city can be impossible in scale while still having plausible contact, atmosphere, reflection, perspective, and shadow

## Product lock

Do not let spectacle alter

- silhouette
- label
- logo
- cap geometry
- count
- color
- material finish
- distinctive functional details

## Failure patterns

Reject

- floating product from missing contact
- subject lit from one side while shadow/reflection implies another
- inserted object using a different camera perspective
- wet environment with a dry, unreactive base
- glass ignoring the background
- surreal effect covering the product identity
- reflection sharper or brighter than the material could produce
- identical blur applied across different depth planes