Extended Features

Besides the official Phigros chart format, pec, and rpe, prpr supports additional chart features. These are available only in prpr and clients built on it:

• Effects
• Video background

All such configuration must live in extra.json at the root of the chart package. To use these features, edit the JSON by hand. If you are not familiar with JSON, see e.g. JSON tutorial.

BPM configuration

Before using these features, you must set the chart BPM in extra.json. Example:

{
   "bpm": [
      { "time": [0, 0, 1], "bpm" : 200.0 },
      { "time": [10, 1, 2], "bpm" : 250.0 }
   ],
   ...
}

This means the chart starts at BPM 200, then at 10.5 beats it changes to 250.

Animation variables

Configs often use animation variables. For example, in RPE, the X position event is just the X coordinate as an animation variable.

prpr supports two forms. The first is a single value (constant over time). The second is the same as in RPE: a list of Event objects. A single event looks like:

{
	"startTime": [0, 0, 1],
	"endTime": [0, 0, 1],
	"easingType": 2,
	"easingLeft": 0.0,
	"easingRight": 1.0,
	"start": ...,
	"end": ...
}

startTime and endTime are the event start and end; easingType is the easing type; easingLeft and easingRight optionally clip the easing.

start and end are the variable values at start and end. The value type depends on the variable; it can be:

• float: single number
• vec2: 2D vector as a two-element array
• color: color as four integers 0–255, format [R, G, B, A]

Example: an animation variable that goes from 0 to 0.1 linearly between two times:

[
	{
		"startTime": [2, 0, 1],
		"endTime": [4, 0, 1],
		"easingType": 2,
		"start": 0.0,
		"end": 0.1
	}
]