api/docs/data-modeling.md

# Data modeling

## objects

### primary shapes

**signs**
* id
* descriptor
* meanings: many-to-many **meanings**
* dh: many-to-many **handshapes**
* ndh: many-to-many **handshapes**
  * one-handed sign = null
  * two-handed sign
    * symmetric = same id as *dh*
    * assymmetric = different id than *dh*
* darm: many-to-many **armshapes**
* ndarm: many-to-many **armshapes**
* nmm: **nonmanual_markers**
* location: text
  - comment - descriptor
* hand_synchronization: **synchronization_modes**
  * comment - the way each hand moves in relation to the other
* arm_synchronization: **synchronization_modes**
  * comment - the way each arm moves in relation to the other
* depiction: many-to-many **media**

**handshapes**
* id
* descriptor: text
* shape: **primes**
* orientation
* finger_movement: many-to-many **prime_movements**
* wrist_movement: many-to-many **hand_movements**
  * comment - rotations from the neutral orientation
* depiction: many-to-many **media**

**primes**
* id
* descriptor: text
* index_finger: **finger_shape**
* middle_finger: **finger_shape**
* ring_finger: **finger_shape**
* pinky_finger: **finger_shape**
* thumb_finger: **thumb_shape**
* thumb_aperture
  * comment - vec3 angle between thumb and hand
* depiction: many-to-many **media**

**finger_shape**
* id
* type:
  * closed
  * bent
  * claw
  * open
* tightness
  * comment - degree of openness; e.g. distinguishes between
  S (fist), O, and flat-O; may be interpreted as the distance of
  the tip of the finger from the base, near the palm

**thumb_shape**
* id
* type:
  * palm
    * pressed against the palm (under the other fingers, if closed), e.g. B
  * fist
    * pressed against the outside of closed fingers, e.g. S
  * parallel
    * extending along the line of the fingers, e.g. A
  * normal
    * extending outward along the normal of the fingers, e.g. 10
  * perpindicular
    * extending outward away from the palm Z-axis, e.g. G

**armshapes**
* id
* descriptor: text
* arm: **arms**
* movement: many-to-many **arm_movements**
* depiction: many-to-many **media**

**arms**
* id
* descriptor: text
* elbow_location
* upper_rotation
* lower_rotation

**nonmanual_markers**
* id
* descriptor: text
* depiction: many-to-many **media**

### movement

**arm_movements**
* id
* descriptor: text
* elbow_motion: many-to-many **motions**
* upper_motion: many-to-many **motions**
* lower_motion: many-to-many **motions**
* depiction
* animation

**motions**
* id
* descriptor: text
* spline

**hand_movements**
* id
* descriptor: text
* target_rotation: **spline**
  * comment - offsets/changes relative to the neutral
* loop: **loop_modes**
* speed
  * comment - quickness of motion between control points
* animation

**prime_movements**
* id
* descriptor: text
* target_position: **spline**
* synchronization: **synchronization_modes**
* loop: **loop_modes**
* speed
  * comment - quickness of motion between control points
* animation

**synchronization_modes**
* id
* mode
  * alternating
    * comment - one finger moves per *loop* before the next moves
  * following
    * comment - one finger moves to target & the next begins movement
  * random
    * comment - fingers move to target in random order
  * concurrent
    * comment - movement of each finger conforms to the other, i.e. is concurrent

**loop_modes**
* id
* mode
  * none
    * comment - finger moves to target & is held
  * pingpong
    * comment - finger moves to target & back to neutral
  * once
    * comment - finger moves to target & back to neutral two times
  * continuous
    * comment - finger moves between target & neutral for the duration

### 3d data

**curve**
a Bezier curve. the number of non-null points determines the type, i.e. linear=cp0+cp1, quadratic=cp0+cp1+cp2, cubic=cp0+cp1+cp2

* id
* cp0: vec3
* cp1: vec3
* cp2: vec3
* cp3: vec3

**spline**
a polybezier, i.e. continuous composite Bezier

* id

**spline_curves**
a link table for the curves of a spline

* spline
* curve

### media

**media**
* id
* image
* video
* gltf: **gltf_object**

**animations**
* id
* pose: many-to-many **poses**
  * comment - only applicable to linked poses
* modifiers
  * comment - gltf representation of modifications to produce animation
* media: many-to-many **media**
  * rendered media depictions

**gltf_objects**
* id
* gltf_data
* url

**poses**
* id
* gltf: **gltf_objects**

**image**
* id
* url

**video**
* id
* url

### semantics

**meanings**
* id
* depictions: many-to-many **images**
* english_desc

## search

### relations

**similars**
* id
* sign_1: **signs**
* sign_2: **signs**