This ADR discusses improvements to the avatar system in Decentraland to enhance user freedom and create a more reliable, flexible, and scalable system. The ADR establishes a prioritization order for wearable visualization, modifies the replacement system to prevent wearables from replacing each other, introduces body fallback to show base body parts when no wearables are equipped, and allows users to force the rendering of hidden wearables. These decisions will serve as the standard for the Decentraland Avatar Assembly System and can be implemented in external platforms. The suggested flow for avatar assembly is also outlined.
Previously, the avatar system has been unreliable and limited over different aspects. To increase users freedom, create a reliable, flexible and scalable system the following changes will be applied:
The different decisions will become the standard base for Decentraland Avatar Assembly System, initially applied in the unity reference client, but then proposed to any external platform that uses the Decentraland avatars.
Previously the hiding and replacing functionality was following a rule of "Last equipped", meaning that replaces and hides were applied based on the last wearable equipped, creating discrepancy and an inconsistent behaviour. Additionally it was not solving situations of mutual hiding (wearable A hiding B and B hiding A) To standardize this an ordered list of categories will be followed to calculate which wearables are hiding which. The proposed priority list is (from most important to least):
All elements associated with the face, such as the mouth, eyes, and eyebrows, directly depend on the visualization of the head. The head is not a wearable itself, so it cannot create circular references, and it is hidden as soon as one or more wearables determine it.
The following example illustrates the expected behavior: If a wearable of type "Mask" hides another wearable of type "Hat", and this in turn hides wearables of type "Mask", the wearable of type "Mask" will have visualization priority, hiding the Hat.
The current result of equipping an item that replaces or hides other wearables is unexpected and inconsistent. When a player navigates through their inventory items, as they equip, unequip, or hide other wearables from other categories without notice, they cannot reverse this behavior when equipping a different wearable. When a wearable unequips another wearable, the latter could be running a portable experience. By deactivating it, any progress or data in memory could be lost, ruining its expected behavior. The decision-making capacity of creators is overlapping with the freedom of choice of players. When a player purchases a wearable, thinking it will combine well with what they already have in their inventory, they may be unpleasantly surprised that these are not compatible. Information about which other wearables are replaced or hidden is not clearly indicated in the marketplace or backpack. There is no real weighty reason for a wearable to unequip another wearable, instead of hiding it to prevent clipping problems.
On the base of that the replacing functionality for new wearables will be removed, pre-existing wearables will see the replacing list being merged with the hiding list.
Previously, by unequipping the upper_body, the lower_body, the feet or the eyebrows, caused the system to fallback to default wearables (t-shirt, pants and shoes). This prevents, for example, players from going barefoot or without t-shirt.
The system will extent the concept of Body by removing the default fallback wearables. These pieces, which can be called "Bare feet", "Naked Top" and "Naked Bottom", are not considered wearables, but rather parts of the base body geometry that are exclusively displayed when no wearables are equipped and there are no other wearables hiding the relevant category.
To extend further players ability to use the wearables they have. If an equipped wearable is hidden by the effect of another wearable, players can unhide them and override this instruction. This forced render effect is removed as soon as another wearable that re-hides that category is equipped, forcing the user to show it again.
In order to store the force render categories, it is proposed to add a new field to the player profile holding a list of overridden hide categories. This list of string will hold the current overridden categories so that each player can render other players (and itself) according to the new rules. As an example:
"forceRender": ["mask", "top_head", "feet"]
This example means that when the avatar is going to be assembled the "mask", "top_head" and "feet" categories will be shown even if other wearables are hiding them.
Here's the avatar definition with the additional forceRender field that will be provided:
{
"timestamp": 1684839566179,
"avatars": [
{
"hasClaimedName": true,
"description": "",
"tutorialStep": 256,
"name": "Username",
"avatar": {
"bodyShape": "urn:decentraland:off-chain:base-avatars:BaseMale",
"wearables": [
"urn:decentraland:off-chain:base-avatars:eyebrows_00",
"urn:decentraland:off-chain:base-avatars:mouth_00",
"urn:decentraland:off-chain:base-avatars:casual_hair_01",
"urn:decentraland:off-chain:base-avatars:beard",
"urn:decentraland:matic:collections-v2:0xc11b9d892e12cfaca551551345266d60e9abff6e:1",
"urn:decentraland:matic:collections-v2:0x84a1d84f183fa0fd9b6b9cb1ed0ff1b7f5409ebb:5",
"urn:decentraland:ethereum:collections-v1:halloween_2020:hwn_2020_ghostblaster_tiara",
"urn:decentraland:ethereum:collections-v1:halloween_2020:hwn_2020_cat_eyes",
"urn:decentraland:off-chain:base-avatars:piratepatch",
"urn:decentraland:matic:collections-v2:0xca7c347ffdeee480092f3b1268550b60ea031077:4",
"urn:decentraland:matic:collections-v2:0x2a3a6d0c92b18102ed189233976c974473a59c87:0"
],
"forceRender": ["mask", "top_head", "feet"],
"emotes": [
{
"slot": 0,
"urn": "raiseHand"
},
{
"slot": 1,
"urn": "urn:decentraland:matic:collections-v2:0x167d6b63511a7b5062d1f7b07722fccbbffb5105:0"
},
{
"slot": 2,
"urn": "urn:decentraland:matic:collections-v2:0x875146d1d26e91c80f25f5966a84b098d3db1fc8:1"
},
{
"slot": 3,
"urn": "urn:decentraland:matic:collections-v2:0x875146d1d26e91c80f25f5966a84b098d3db1fc8:2"
},
{
"slot": 4,
"urn": "urn:decentraland:matic:collections-v2:0x875146d1d26e91c80f25f5966a84b098d3db1fc8:0"
},
{
"slot": 5,
"urn": "headexplode"
},
{
"slot": 6,
"urn": "tektonik"
},
{
"slot": 7,
"urn": "clap"
},
{
"slot": 8,
"urn": "handsair"
},
{
"slot": 9,
"urn": "dance"
}
],
"snapshots": {
"body": "https://interconnected.online/content/contents/bafkreihhwboio77zsl6evt6i3f5iun5ek65w7dyuvl44xwk33zts4qx2v4",
"face256": "https://interconnected.online/content/contents/bafkreiddnf2ixknlhio4hk7ao47agiwkqs43cg3nkoyibckgmhz5iqn3he"
},
"eyes": {
"color": {
"r": 0.529411792755127,
"g": 0.501960813999176,
"b": 0.47058823704719543,
"a": 1
}
},
"hair": {
"color": {
"r": 0.10980392247438431,
"g": 0.10980392247438431,
"b": 0.10980392247438431,
"a": 1
}
},
"skin": {
"color": {
"r": 0.800000011920929,
"g": 0.6078431606292725,
"b": 0.46666666865348816,
"a": 1
}
}
},
"ethAddress": "0x1hd7fl09yivcn7z6asc0a8af9c3b1ba28hdy65sd",
"userId": "0x1hd7fl09yivcn7z6asc0a8af9c3b1ba28hdy65sd",
"version": 12,
"hasConnectedWeb3": true
}
]
}
With the points previously discovered, the suggested procedure to visualize an avatar is the following:
POST https://content-server/content/active {"pointers":
["0xaddress"]}
)
POST https://content-server/content/active {"pointers": ["urn1",
"urn2"]}
)
data.hides in each wearable definition )
forceRender )
/**
* @param profile - holds the wearables equipped, bodyShape and the forceRender parameter
* @param forceAll - whether ALL the hides in wearables equipped should be considered or not
* @returns the set of categories that should be hidden
*/
function getHiddenList(profile: UserProfile, forceAll: boolean = false): HideableCategory[] {
const alreadyHidden = new Set<HideableWearableCategory>()
const wearables: Map<WearableCategory, Wearable> = profile.wearables
for (const category of categoriesPriority) {
const wearable = wearables.get(category)
if (!wearable) {
continue
}
if (!forceAll) {
if (alreadyHidden.has(category)) {
continue
}
}
// getHides provides the union of hides and replaces given the representation
// and also add the provided by the category (skin case)
for (const slot of getHides(wearable, profile.bodyShape)) {
alreadyHidden.add(slot)
}
}
return Array.from(alreadyRemoved).filter((category) => !profile.forceRender.includes(category))
}
// 1) Build the hidden list
const toHide = getHiddenList(profile)
// 2) Remove the hidden wearables
for (const category of toHide) {
wearables.delete(category)
}
// 3) Compute the current hidden list for hiding parts of the bodyshape
const hidden = getHiddenList(profile, true)
const bodyShape = getBodyShape(profile, hidden)
Given the next list of wearables with the hides as the array value:
{
"helmet": ["top_head", "head", "hair", "earring"],
"top_head": ["hat"],
"hands_wear": ["hands"],
"hat": ["helmet", "hair"]
}
In step (1), the toHide array is as follows:
[ "top_head", "head", "hair", "earring",
"helmet", "hair" ]. Consequently, in step (2), the wearables helmet and top_head are
removed.
With the remaining wearables hands_wear and hat, the resulting
hidden array becomes: [ "hands", "hair" ]. Therefore, the
bodyShape should hide both the hands and hair. Note
that if we had used the original toHide list to determine what body parts to
conceal, the head would be hidden in the final outcome.
Now, consider the scenario where top_head is included in the forceRender value:
in this case, the toHide list remains the same, except for the exclusion of
top_head. As a result, in step (2), this wearable is not removed. Interestingly,
the hidden list now changes in (3), incorporating hat. However, this
does not affect the bodyShape or alter the wearable list in any way.