# Conditions

An image's **Conditions** view decides where WordPress uses it. Without any
condition group an image is never used automatically; it can still be rendered
with the [PHP functions](/docs/pixel/rendering/function.md) or the
[shortcode](/docs/pixel/rendering/shortcode.md).

## Groups and rows

**Add new condition** adds a group. A group starts with its output, and
**And** adds rows that narrow it down.

- All rows in a group must match.
- Groups are independent: the image is used for every group that matches.
- Each group has one output. To use an image for two outputs, for example Open
  Graph and Featured image, add a group for each.

Each row compares a parameter with a value using **is equal to** or **is not
equal to**.

## Outputs

### Open Graph, Twitter Card, Open Graph + Twitter Card

On a matching front-end page Pixel writes the rendered image into the page's
`og:image` tag, the `twitter:image` tag, or both. It replaces the tag an SEO
plugin or theme printed, and an `og:image:secure_url` tag when there is one,
keeps a single copy of each, and adds `og:image` or `twitter:image` when the
page has none. The image is rendered for the page's current post.

### Featured image

Pixel replaces the featured image of every matching post wherever the theme
shows it, with the rendered image at the canvas's size and an empty `alt`.
Each post is checked as it appears, so on an archive one design can give every
post its own image.

A post without a featured image of its own gets one too. WordPress needs a
media library attachment to print featured image markup, so Pixel borrows the
newest one as a stand-in, which requires at least one item in the media
library.

### Block editor sidebar

Pixel adds a panel to the block editor's sidebar that shows the image rendered
for the post being edited, with a **Download** button. The group's **Panel
name** is the panel's title, `SleekPixel` when left empty.

The panel evaluates only the **Post type**, **Post** and **Post status** rows
of its group and treats every other row as met. It appears only for users who
can manage options, as the panel renders through Pixel's REST operations.

## Parameters

### Values

- **Post type**, **Post**, **Post status** and **Page template**: the current
  post's type, ID, status and page template.
- **Taxonomy**: matches the archive of a taxonomy, such as a category or tag
  archive. It does not match single posts; use **Term** for those.
- **Term**: chosen by searching the site's public taxonomies. On a single
  post, and for each post when featured images are replaced, matches when the
  post has the term in any taxonomy. On a term archive it matches when the
  archive is that term.

### WordPress conditions

Each corresponds to a WordPress conditional tag, compared with the `true` or
`false` chosen in the row: **Single** **is equal to** `true` matches single
posts, and **is equal to** `false` or **is not equal to** `true` every other
page. A row saved without a value counts as `true`.

| Parameter            | Tag                                         |
| -------------------- | ------------------------------------------- |
| Is home              | `is_home()`                                 |
| Is front page        | `is_front_page()`                           |
| Is page              | `is_page()`                                 |
| Is single            | `is_single()`                               |
| Is singular          | `is_singular()`                             |
| Is search page       | `is_search()`                               |
| Is archive           | `is_archive()`                              |
| Is post type archive | `is_post_type_archive()`                    |
| Is category archive  | `is_category()`                             |
| Is tag archive       | `is_tag()`                                  |
| Is taxonomy archive  | `is_tax()`                                  |
| Is author archive    | `is_author()`                               |
| Is date archive      | `is_date()`                                 |
| Is year archive      | `is_year()`                                 |
| Is month archive     | `is_month()`                                |
| Is day archive       | `is_day()`                                  |
| Is time archive      | `is_time()`                                 |
| Is attachment        | `is_attachment()`                           |
| Is a 404 page        | `is_404()`                                  |
| Has featured image   | `has_post_thumbnail()` for the current post |

### Custom

Conditions a site registers with the `sleekPixel/conditions` filter appear
under their label. Each has an `id`, a `label` and a `value` computed for the
current request.

- When the `id` starts with `is` or `has` and the value is a boolean, the row
  works like a WordPress condition and compares the value with the `true` or
  `false` chosen in the row.
- Otherwise the row compares the value with the text you enter.

Use an `id` in lowercase letters, digits, `_` and `-`. The editor stores the
row as `custom_` followed by the ID WordPress's `sanitize_key()` makes of it,
which lowercases it, while the front end compares with the ID as registered,
so an ID with capital letters never matches. See
[PHP hooks](/docs/pixel/hooks/php.md#conditions) for an example.