Bar Charts

Bar charts display data as 3D rectangular bars, where each bar's height represents a numeric value and its position along the X-axis represents a category. Hydrant renders bars in a full 3D scene with configurable dimensions, colors, animations, labels, and a graph block container.

Overview

A bar chart scene is built from one or more dataset selections. Each selection produces a set of bar entities positioned along the X-axis. Bars grow upward from a shared ground plane, with their height scaled proportionally to the data values.

Entity Hierarchy

Bar chart scenes use the following entity structure:

Data Container — Top-level group that holds all dataset selections
- Bar Group (one per selection) — Groups bars from a single selection; carries the selection's transform (position, rotation)
  - Bar — Individual bar entities with position, dimensions, and color
- Bar Group (second selection, if present) — Bars from a second dataset layered alongside
Graph Block — Optional L-shaped container (ground + back wall)
Grid / Scale — Optional axis lines and numeric labels

Bar Dimensions

These settings are configured per dataset selection in the Data panel.

Bar Width — Width of each bar along the X-axis (0.1 – 2.0).

Bar Depth — Depth of each bar along the Z-axis (0.1 – 2.0).

Max Height — Maximum bar height (1 – 5). The tallest data value will reach this height; other bars are scaled proportionally.

Bar Spacing — Space between adjacent bars (0.0 – 2.0). Wider spacing spreads bars apart; tighter spacing packs them closer together.

Scale & Value Mapping

The Y-axis scale determines how data values map to bar heights. Scale settings are configured in the Data panel.

Scale Mode — How the value range is calculated:

Zero-Based (Include 0): Scale starts at 0 and extends to the maximum data value (with optional padding)
Data Range (Fit to Data): Scale spans from the minimum to the maximum data value
Manual Range: Use custom minimum and maximum values

Padding — Extra space above the highest bar as a percentage (0 – 50%). Helps create round numbers on the scale. Available in Zero-Based and Data Range modes only.

Min / Max Value — Manual override for the scale endpoints (manual mode only).

Step Size — Interval between scale labels in manual mode (0.1 – 1000).

Intermediate Lines — Number of secondary grid lines between main scale labels (0 – 4).

When multiple selections share a scene, the scale is computed globally so all bars use the same value range.

Animation

Bar animations are configured per selection in the Data panel under Animation Timing.

Animation Type:

Staggered (One after the other) — Bars animate sequentially from left to right. Each bar begins its grow animation after the previous one has started, creating a wave effect.
Delayed — All bars animate simultaneously, but each bar starts with a configurable delay between them.
Not Animated — Bars appear at their full height immediately.

Delay Before — Pause before the first bar begins animating (0.0 – 5.0 seconds).

Delay After — Pause after the last bar finishes animating (0.0 – 5.0 seconds).

Delay Between — Time gap between each bar when using the "Delayed" type (0.0 – 2.0 seconds).

Grow Behavior

All bars start from a uniform low height (a thin slab) and grow upward to their target height. This ensures a consistent visual starting point regardless of final value. The bar's base stays pinned to the ground while the top rises.

Labels

Labels for bar charts are configured in the Labels panel. Bar charts support all standard label types:

Value Labels — Show the numeric value on or near each bar
Category Labels — Show the category name, typically below each bar
Scale Labels — Appear on the Y-axis
Custom Labels — User-defined, freely positioned or data-linked

Anchor Points

Value and category labels can be anchored to specific positions on each bar:

Top — Attaches to the top face of the bar (default for value labels)
Center — Attaches to the vertical midpoint of the bar
Bottom — Attaches to the base of the bar (default for category labels)

During animation, anchor points move with the bar as it grows, so labels stay correctly positioned throughout the animation.

Graph Block

The graph block is an optional L-shaped container (ground platform + back wall) configured in the Scene panel. It provides spatial context for the bars and serves as a mounting surface for the scale.

Grid and Scale

Grid lines and scale numbers provide visual reference for reading values. These are configured in the Scene panel.

Multi-Dataset Support

A single bar chart scene can display data from multiple selections. Each selection produces its own bar group, and the groups are positioned side by side or layered depending on their transform settings.

Each selection has independent bar settings (width, depth, spacing, color)
The Y-axis scale is computed globally across all selections for consistency
Animation timing can be set independently per selection
The data container entity provides a shared bounding box encompassing all selections

Entity Overrides

Individual bars can be customized through the Object Inspector in the Scene Tree:

Position — Offset the bar from its computed position
Rotation — Rotate the bar
Scale — Resize the bar
Color — Override the bar's color
Visibility — Show or hide individual bars
Opacity — Adjust bar transparency

Overrides persist across data reprocessing — if you reprocess the scene, your per-bar customizations are reapplied to matching entities.