docs._extensions.30_rendering_hints.md Maven / Gradle / Ivy
---
layout: page
title: Rendering Hints Extension
permalink: /extensions/rendering_hints
---
## Rendering Hints
The Series API provides I/O mechanisms to render charts so that clients may directly request
data via `accept=image/png` HTTP header. However, styles are chosen either randomly or by
passing the `style=...` parameter. As the data provider should know best what style fit best
to a particular dataset, it can be configured as rendering hints.
The rendering hints are available to a client as `extra` data for a given dataset.
### Configuration Location
Status intervals can be configured for datasets having a particular phenomenon or each individually
(overriding a possibly matching phenomenona config). Each entry provides a title, upper and lower
limit and some color hint a client may use to render properly.
For example:
```json
{
"phenomenonStyles": {
"3": {
"style": {
"chartType": "bar",
"properties": {
"interval": "byHour",
"width": 0.8,
"color": "#0000ff"
}
}
}
},
"datasetStyles": {
"2": {
"style": {
"chartType": "line",
"properties": {
"lineType": "solid",
"width": 1,
"color": "#1E90FF"
},
"referenceValueStyleProperties": {
"278" : {
"chartType": "line",
"properties": {
"lineType": "solid",
"width": 1,
"color": "#1E90FF"
}
}
}
}
}
}
}
```
{:.n52-callout .n52-callout-info}
`timeseriesStyles` and `seriesStyles` mean the same as `datasetStyles` and is kept
for backwards compatibility reasons.