#summary Explanation of hats, how Hedgewars draws them and how one can create them

= Hats =

== Introduction ==

In Hedgewars, every hedgehog can optionally wear its own hat as decoration. They can be selected on a per-hog basis in the team editor.

== Types of hats ==

There are two types of hats: normal hats and team hats.

Normal hats look always the same.

Team hats are hats which will be colored accordingly to the team color.

I.e. if a hedgehog plays in a red team, its hat will we red.

Additionally, hats can be either static or animated.

In the default Hedgewars installation, most hats are normal hats, and many hats are animated.

== Data structure ==

Hats are specified as PNG files with alpha channel.

They consist of a set of sub-images of a size 32px×32px each.

Hedgewars counts the sub-images, or animation frames, from top-left to

bottom-left, then it goes on with the next column, etc.

=== Static normal hats ===

These are the simplest hats. It's just a single 32×32 image containing the hat. This image will be put on the hedgehog's head with a vertical offset of 5 pixels.

That's it!

=== Static team hats ===

This is a 64px×32px image with 2 frames. The left half is the base coloring of the helmet, the right half should _only_ use grayscale colors. The left part may be completely blank. The same offset of 5 pixels applies here.

To create the final image, Hedgewars will use the right base image and use the colored right part of the image and simply overlay it on the left image.

=== Animated normal hats ===

Animated normal hats use an image of a total size of 64px×512px. Only the first

19 frames are used, the remainder of the image is unused. It is best to keep the unused area transparent.

=== Animated team hats ===

Animated team hats use an image of a total size of 128px×512px. This image is similar to that of animated normal hats, the same pattern is repeated 64 pixels to the right.

The team hat image consists of two “halves”: The left half is the base coloring of the helmet, the right half should _only_ use grayscale colors. The left part may be completely blank. So you have basically two sets of helmet animations. Again, both animations have exactly 19 frames, the remainder is unused.

Hedgewars will use the right base image and use the colored right part of the image and simply overlay it.

Transparent pixels on the right part will not be overlayed. This way, you can decide which parts of the helmet become colored and which won’t.

== Alignment of hats ==

When creating hats, it is important to know where the hat will be actually placed.

For static hats, this is trivial: Hedgewars will just move the hat up by 5 pixels before drawing it on the hedgehog.

The hat will automatically slightly bounce up and down with the hedgehog idle animation.

Now to animated hats:

In the game, Hedgewars will use the idling frames (see `Data/Graphics/Hedgehog/Idle.png`)

together with the hat frames. For static hats, the reference point is the first frame of `Idle.png`.

If a hat is used, Hedgewars will draw the hat over the idling hedgehog for each frame, but

first it will move the hat’s frame up by 5 pixels.

The first frame of the hat animation will be drawn over the first frame of the idle animation,

the second frame of the hat animation will be drawn over the second frame of the idle animation,

and so on.

Another tricky part in creating hats is the fact that the idle hedgehog moves slightly up and down.

This means, a good hat must consider this, otherwise the hat does not seem to be actually on the

hedgehog’s hat, because it does not move with the hedgehog.

This table shows the relative height of the idle hedgehog compared to the frist frame of `Idle.png`:

|| *nth frame of `Idle.png`* || *Offset to first frame* ||

|| 1 || 0 px ||

|| 2 || 0 px ||

|| 3 || +1 px ||

|| 4 || 0 px ||

|| 5 || 0 px ||

|| 6 || 0 px ||

|| 7 || 0 px ||

|| 8 || +1 px ||

|| 9 || 0 px ||

|| 10 || 0 px ||

|| 11 || 0 px ||

|| 12 || 0 px ||

|| l3 || +1 px ||

|| 14 || 0 px ||

|| 15 || 0 px ||

|| 16 || 0 px ||

|| 17 || −1 px ||

|| 18 || 0 px ||

|| 19 || 0 px ||

This is how to read this table: If you would like to create a simple hat with no fancy animation, like, let’s say, a fedora, you would like the hat to “follow” the hedgehog. You could, for example, draw and align the hat image on the first frame, then copy it on all other frames and apply the offsets to the four “special” frames.

== Installation ==

To install a hat, you have to save the file into `Data/Graphics/Hats` in your Hedgewars

user data directory. The file name _must_ end with “`.png`”.

The Hedgewars frontend will display the same name as the file name you used, minus the file name

suffix. For example, the file “`Awesome Example Hat.png`” would be displayed as “Awesome Example Hat”.

Hedgewars will always use the very first frame of a hat image to create the preview in the team editor. This also applies to team hats.

== Templates ==

For your convenience, we have created some templates to ease the creation of hats. You can use them as background layer to help you align your hats.

=== Static normal hats ===

Just use the template for animated normal hats and crop it to the first frame (top left 32×32 pixels).

=== Animated normal hats ===

A basic PNG template is [https://www.hedgewars.org/images/Hat_Template.png Hat_Template.png]. You can use this image as a background layer. This image shows a colored checkerboard pattern, each field represents an animation frame. The green and red fields are those where the idle hedgehog has an offset of +1px or −1 px (see above). The black fields are the unused frames. In the front, the idle hedgehog can be seen but shifted 5 pixels lower and the 5 lowest pixels cut off.

You can use this image to exactly align the hat properly.

This image is also available as XCF for GIMP users: [https://www.hedgewars.org/images/Hat_Template.xcf Hat_Template.xcf]. It got an additional layer and you can easily toggle a couple of layers on and off.

=== Animated team hats ===

You can use [https://www.hedgewars.org/images/Team_Hat_Template.png Team_Hat_Template.png]. This is similar to the previous PNG. The hedgehogs on the right half are in gray to remind you that you only should use grayscale colors on this side.

The XCF source of this file is here: [https://www.hedgewars.org/images/Team_Hat_Template.xcf Team_Hat_Template.xcf].

== Sharing hats ==

Custom hats (hats which are not part of the official Hedgewars installation) are only visible to other players if they have the hat installed under the same file name.

In case the other player does not have the custom hat installed, the player will see no hat instead.

You are encouraged to share your hats in the thread “[https://www.hedgewars.org/node/690 Hats! additions, submissions, information.]”, where submissions are considered for official inclusion into Hedgewars.