nandi/freeqsay-nim · avatar.nim

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avatar.nim · 279 lines · 8.6 KBNim    Blame HistoryRaw
freeqsay: Nim port of the Clojure implementation   1## Deterministic avatar system (avatar-v1).
3## canonical seed = HKDF-SHA256(ikm=DID, salt="freeq-world-avatar", info="avatar-v1")
4## All traits are abstract — nothing is inferred from profile data.
6import std/[math, tables]
7import ./sha256
Traits* = OrderedTable[string, string]
Avatar* = object
  schema*: string
  did*: string
  baseGenerator*: string
  canonicalSeedHex*: string
  traits*: Traits
Facing* = enum
  fSouth = "south", fNorth = "north", fEast = "east", fWest = "west"
Sprite* = object
  width*, height*: int
  pixels*: seq[int]     ## palette indices
  palette*: seq[string]
27const traitKeys* = [
"body_silhouette", "head_shape", "skin_palette", "hair_shape", "hair_palette",
"eye_pixels", "shirt_jacket", "pants_skirt", "shoes", "accessory",
"idle_movement", "walk_cadence", "speech_sound", "accent_palette",
"arrival_effect", "musical_leitmotif"]
33const options*: array[15, (string, seq[string])] = [
("body_silhouette", @["slim", "broad", "round", "tall", "compact", "angular"]),
("head_shape", @["round", "square", "oval", "wide"]),
# stylized fictional palette — deliberately includes non-naturalistic hues
("skin_palette", @["#e8b48c", "#c68863", "#8d5a3b", "#5c3a26", "#f4d6b8",
                   "#9fb8ad", "#b7a6d9", "#7d9c6f"]),
("hair_shape", @["crop", "spikes", "bob", "long", "curls", "mohawk", "bald", "bun"]),
("hair_palette", @["#2b2b3a", "#5a3825", "#c9a227", "#b8434e", "#3f7cac",
                   "#67c26b", "#e8e6df", "#8447ad"]),
("eye_pixels", @["dot", "wide", "wink", "visor"]),
("shirt_jacket", @["#3f7cac", "#b8434e", "#67c26b", "#c9a227", "#8447ad",
                   "#3a9188", "#d97b29", "#6d7680"]),
("pants_skirt", @["#31394d", "#5a3825", "#3a5a40", "#6b3a55", "#444444", "#7a5c99"]),
("shoes", @["#1e1e28", "#5a3825", "#b8434e", "#e8e6df"]),
("accessory", @["none", "hat", "glasses", "scarf", "antenna", "flower",
                "headphones", "badge"]),
("idle_movement", @["bob", "sway", "blink", "tap"]),
("walk_cadence", @["steady", "bouncy", "brisk", "ambling"]),
("speech_sound", @["beep", "blip", "burble", "chirp", "hum"]),
("accent_palette", @["#ffd166", "#06d6a0", "#ef476f", "#118ab2", "#f78c6b", "#9b5de5"]),
("arrival_effect", @["sparkle", "dissolve", "drop", "teleport-rings"])]
55func optionsFor*(key: string): seq[string] =
for (k, v) in options:
  if k == key: return v
raise newException(KeyError, "no options for trait " & key)
60type Prng* = object
a, b, c, d: uint32
63func u32le(seed: openArray[byte], i: int): uint32 =
for k in 0 ..< 4:
  result = result or (uint32(seed[i + k]) shl (8 * k))
67func initPrng*(seed: openArray[byte]): Prng =
## sfc32 seeded from the first 16 bytes of `seed` — bit-identical to the
## JavaScript original the fixture was generated with.
Prng(a: u32le(seed, 0), b: u32le(seed, 4), c: u32le(seed, 8), d: u32le(seed, 12))
72func next*(p: var Prng): float =
## Next double in [0, 1).
let t = p.a + p.b + p.d
let d = p.d + 1
let a = p.b xor (p.b shr 9)
let b = p.c + (p.c shl 3)
let c = ((p.c shl 21) or (p.c shr 11)) + t
p = Prng(a: a, b: b, c: c, d: d)
float(t) / 4294967296.0
82func pick*(p: var Prng, opts: openArray[string]): string =
let i = int(floor(p.next() * float(opts.len)))
opts[min(i, opts.len - 1)]
86func canonicalSeed*(did: string): seq[byte] =
## 32-byte canonical seed for a DID.
hkdf(did, "freeq-world-avatar", "avatar-v1", 32)
90func deriveAvatar*(did: string): Avatar =
let seed = canonicalSeed(did)
var rng = initPrng(seed)
var traits: Traits
for key in traitKeys:
  traits[key] =
    if key == "musical_leitmotif":
      # pointer to the leitmotif derivation (own HKDF domain)
      "motif-v1"
    else:
      pick(rng, optionsFor(key))
Avatar(schema: "freeq.at/profile/avatar/v1",
       did: did,
       baseGenerator: "avatar-v1",
       canonicalSeedHex: toHex(seed),
       traits: traits)
108
109
112
113
SHIRT = 3
PANTS = 4
116
117
ACCENT = 7
WHITE = 8
121func renderSpritePixels*(av: Avatar, facing = fSouth, frame = 0): Sprite =
## Procedural 16x24 pixel body. Rows: hair/head 0-9, torso 10-17, legs 18-21,
## shoes 22-23. Facing changes the face; walk frames swing arms and legs.
let t = av.traits
var px = newSeq[int](W * H)
proc put(x, y, c: int) =
  if x >= 0 and x < W and y >= 0 and y < H:
    px[y * W + x] = c
proc hspan(x0, x1, y, c: int) =
  for x in x0 .. x1:
    put(x, y, c)
  silhouette = t["body_silhouette"]
  bodyW = if silhouette in ["broad", "round"]: 10
          elif silhouette == "slim": 6
          else: 8
  bodyX0 = (W - bodyW) div 2
  bodyX1 = bodyX0 + bodyW - 1
  headShape = t["head_shape"]
  headW = if headShape == "wide": 10 else: 8
  headX0 = (W - headW) div 2
  headX1 = headX0 + headW - 1
  headTop = if silhouette == "tall": 1 else: 2
  hair = t["hair_shape"]
  acc = t["accessory"]
151
for y in headTop ..< 10:
  let shrink = if headShape in ["round", "oval"] and (y == headTop or y == 9): 1 else: 0
  hspan(headX0 + shrink, headX1 - shrink, y, SKIN)
156
if hair != "bald":
  hspan(headX0, headX1, headTop, HAIR)
  hspan(headX0, headX1, headTop + 1, HAIR)
  if hair in ["spikes", "mohawk"]:
161
      mohawk = hair == "mohawk"
      start = headX0 + (if mohawk: headW div 2 - 1 else: 0)
      stop = if mohawk: headX0 + headW div 2 else: headX1
      step = if mohawk: 1 else: 2
    var x = start
    while x <= stop:
      put(x, headTop - 1, HAIR)
      x += step
  if hair in ["bob", "long", "curls"]:
    put(headX0, headTop + 2, HAIR)
    put(headX1, headTop + 2, HAIR)
    put(headX0, headTop + 3, HAIR)
    put(headX1, headTop + 3, HAIR)
    if hair == "long":
      put(headX0, headTop + 4, HAIR)
      put(headX1, headTop + 4, HAIR)
  if hair == "bun":
    put(W div 2, headTop - 1, HAIR)
# face (not shown when facing north)
if facing != fNorth:
    eyeY = headTop + 4
    eyes = t["eye_pixels"]
    mid = W div 2
    eyeL = case facing
           of fEast: mid
           of fWest: headX0 + 1
           else: headX0 + 2
    eyeR = case facing
           of fEast: headX1 - 1
           of fWest: mid - 1
           else: headX1 - 2
  if eyes == "visor":
    hspan(eyeL, eyeR, eyeY, ACCENT)
197
    put(eyeL, eyeY, INK)
    if eyes != "wink":
      put(eyeR, eyeY, INK)
    if eyes == "wide":
      put(eyeL, eyeY - 1, WHITE)
      put(eyeR, eyeY - 1, WHITE)
elif hair != "bald":
  # back of head is hair
  for y in headTop ..< 9:
    hspan(headX0, headX1, y, HAIR)
209
for y in 10 ..< 18:
  hspan(bodyX0, bodyX1, y, SHIRT)
# accent stripe
hspan(bodyX0, bodyX1, 13, ACCENT)
# arms (swing with walk frame)
let swing = case frame
            else: -1
put(bodyX0 - 1, 11 + swing, SKIN)
put(bodyX0 - 1, 12 + swing, SKIN)
put(bodyX1 + 1, 11 - swing, SKIN)
put(bodyX1 + 1, 12 - swing, SKIN)
225
  legW = max(2, bodyW div 2 - 1)
  gap = case frame
        else: 0
  legL0 = W div 2 - gap div 2 - legW
  legR0 = W div 2 + int(ceil(float(gap) / 2.0))
for y in 18 ..< 22:
  hspan(legL0, legL0 + legW - 1, y, PANTS)
  hspan(legR0, legR0 + legW - 1, y, PANTS)
for y in 22 ..< 24:
  hspan(legL0, legL0 + legW - 1, y, SHOE)
  hspan(legR0, legR0 + legW - 1, y, SHOE)
# accessory
242
of "hat":
  hspan(headX0 - 1, headX1 + 1, headTop, ACCENT)
  hspan(headX0, headX1, headTop - 1, ACCENT)
of "antenna":
  put(W div 2, headTop - 1, INK)
  put(W div 2, headTop - 2, ACCENT)
of "scarf":
  hspan(bodyX0, bodyX1, 10, ACCENT)
of "glasses":
  if facing != fNorth:
    hspan(headX0 + 1, headX1 - 1, headTop + 4, INK)
of "headphones":
  put(headX0 - 1, headTop + 3, ACCENT)
  put(headX1 + 1, headTop + 3, ACCENT)
of "flower":
  put(headX1, headTop + 1, ACCENT)
of "badge":
  put(bodyX0 + 1, 11, ACCENT)
else: discard
Sprite(width: W, height: H, pixels: px,
       palette: @["transparent", t["skin_palette"], t["hair_palette"],
                  t["shirt_jacket"], t["pants_skirt"], t["shoes"],
                  "#14141c", # outline/eyes
                  t["accent_palette"], "#ffffff"])
269func spriteHash*(av: Avatar): string =
## Deterministic content hash over all four facings — conformance fixture value.
var bs: seq[byte]
for facing in [fSouth, fNorth, fEast, fWest]:
  let s = renderSpritePixels(av, facing, 0)
  for p in s.pixels:
    bs.add byte(p and 255)
  for color in s.palette:
    for ch in color:
      bs.add byte(ch)
toHex(digest(bs))

freeqsay: Nim port of the Clojure implementation fa53aa2 nandi 6h ago	1	## Deterministic avatar system (avatar-v1).
	2	##
	3	## canonical seed = HKDF-SHA256(ikm=DID, salt="freeq-world-avatar", info="avatar-v1")
	4	## All traits are abstract — nothing is inferred from profile data.
	5
	6	import std/[math, tables]
	7	import ./sha256
	8
	9	type
	10	Traits* = OrderedTable[string, string]
	11
	12	Avatar* = object
	13	schema*: string
	14	did*: string
	15	baseGenerator*: string
	16	canonicalSeedHex*: string
	17	traits*: Traits
	18
	19	Facing* = enum
	20	fSouth = "south", fNorth = "north", fEast = "east", fWest = "west"
	21
	22	Sprite* = object
	23	width, height: int
	24	pixels*: seq[int] ## palette indices
	25	palette*: seq[string]
	26
	27	const traitKeys* = [
	28	"body_silhouette", "head_shape", "skin_palette", "hair_shape", "hair_palette",
	29	"eye_pixels", "shirt_jacket", "pants_skirt", "shoes", "accessory",
	30	"idle_movement", "walk_cadence", "speech_sound", "accent_palette",
	31	"arrival_effect", "musical_leitmotif"]
	32
	33	const options*: array[15, (string, seq[string])] = [
	34	("body_silhouette", @["slim", "broad", "round", "tall", "compact", "angular"]),
	35	("head_shape", @["round", "square", "oval", "wide"]),
	36	# stylized fictional palette — deliberately includes non-naturalistic hues
	37	("skin_palette", @["#e8b48c", "#c68863", "#8d5a3b", "#5c3a26", "#f4d6b8",
	38	"#9fb8ad", "#b7a6d9", "#7d9c6f"]),
	39	("hair_shape", @["crop", "spikes", "bob", "long", "curls", "mohawk", "bald", "bun"]),
	40	("hair_palette", @["#2b2b3a", "#5a3825", "#c9a227", "#b8434e", "#3f7cac",
	41	"#67c26b", "#e8e6df", "#8447ad"]),
	42	("eye_pixels", @["dot", "wide", "wink", "visor"]),
	43	("shirt_jacket", @["#3f7cac", "#b8434e", "#67c26b", "#c9a227", "#8447ad",
	44	"#3a9188", "#d97b29", "#6d7680"]),
	45	("pants_skirt", @["#31394d", "#5a3825", "#3a5a40", "#6b3a55", "#444444", "#7a5c99"]),
	46	("shoes", @["#1e1e28", "#5a3825", "#b8434e", "#e8e6df"]),
	47	("accessory", @["none", "hat", "glasses", "scarf", "antenna", "flower",
	48	"headphones", "badge"]),
	49	("idle_movement", @["bob", "sway", "blink", "tap"]),
	50	("walk_cadence", @["steady", "bouncy", "brisk", "ambling"]),
	51	("speech_sound", @["beep", "blip", "burble", "chirp", "hum"]),
	52	("accent_palette", @["#ffd166", "#06d6a0", "#ef476f", "#118ab2", "#f78c6b", "#9b5de5"]),
	53	("arrival_effect", @["sparkle", "dissolve", "drop", "teleport-rings"])]
	54
	55	func optionsFor*(key: string): seq[string] =
	56	for (k, v) in options:
	57	if k == key: return v
	58	raise newException(KeyError, "no options for trait " & key)
	59
	60	type Prng* = object
	61	a, b, c, d: uint32
	62
	63	func u32le(seed: openArray[byte], i: int): uint32 =
	64	for k in 0 ..< 4:
65	result = result or (uint32(seed[i + k]) shl (8 * k))
66
67	func initPrng*(seed: openArray[byte]): Prng =
68	## sfc32 seeded from the first 16 bytes of `seed` — bit-identical to the
69	## JavaScript original the fixture was generated with.
70	Prng(a: u32le(seed, 0), b: u32le(seed, 4), c: u32le(seed, 8), d: u32le(seed, 12))
71
72	func next*(p: var Prng): float =
73	## Next double in [0, 1).
74	let t = p.a + p.b + p.d
75	let d = p.d + 1
76	let a = p.b xor (p.b shr 9)
77	let b = p.c + (p.c shl 3)
78	let c = ((p.c shl 21) or (p.c shr 11)) + t
79	p = Prng(a: a, b: b, c: c, d: d)
80	float(t) / 4294967296.0
81
82	func pick*(p: var Prng, opts: openArray[string]): string =
83	let i = int(floor(p.next() * float(opts.len)))
84	opts[min(i, opts.len - 1)]
85
86	func canonicalSeed*(did: string): seq[byte] =
87	## 32-byte canonical seed for a DID.
88	hkdf(did, "freeq-world-avatar", "avatar-v1", 32)
89
90	func deriveAvatar*(did: string): Avatar =
91	let seed = canonicalSeed(did)
92	var rng = initPrng(seed)
93	var traits: Traits
94	for key in traitKeys:
95	traits[key] =
96	if key == "musical_leitmotif":
97	# pointer to the leitmotif derivation (own HKDF domain)
98	"motif-v1"
99	else:
100	pick(rng, optionsFor(key))
101	Avatar(schema: "freeq.at/profile/avatar/v1",
102	did: did,
103	baseGenerator: "avatar-v1",
104	canonicalSeedHex: toHex(seed),
105	traits: traits)
106
107	const
108	W* = 16
109	H* = 24
110
111	const
112	SKIN = 1
113	HAIR = 2
114	SHIRT = 3
115	PANTS = 4
116	SHOE = 5
117	INK = 6
118	ACCENT = 7
119	WHITE = 8
120
121	func renderSpritePixels*(av: Avatar, facing = fSouth, frame = 0): Sprite =
122	## Procedural 16x24 pixel body. Rows: hair/head 0-9, torso 10-17, legs 18-21,
123	## shoes 22-23. Facing changes the face; walk frames swing arms and legs.
124	let t = av.traits
125	var px = newSeq[int](W * H)
126
127	proc put(x, y, c: int) =
128	if x >= 0 and x < W and y >= 0 and y < H:
129	px[y * W + x] = c
130
131	proc hspan(x0, x1, y, c: int) =
132	for x in x0 .. x1:
133	put(x, y, c)
134
135	let
136	silhouette = t["body_silhouette"]
137	bodyW = if silhouette in ["broad", "round"]: 10
138	elif silhouette == "slim": 6
139	else: 8
140	bodyX0 = (W - bodyW) div 2
141	bodyX1 = bodyX0 + bodyW - 1
142
143	headShape = t["head_shape"]
144	headW = if headShape == "wide": 10 else: 8
145	headX0 = (W - headW) div 2
146	headX1 = headX0 + headW - 1
147	headTop = if silhouette == "tall": 1 else: 2
148	hair = t["hair_shape"]
149	acc = t["accessory"]
150
151	# head
152	for y in headTop ..< 10:
153	let shrink = if headShape in ["round", "oval"] and (y == headTop or y == 9): 1 else: 0
154	hspan(headX0 + shrink, headX1 - shrink, y, SKIN)
155
156	# hair
157	if hair != "bald":
158	hspan(headX0, headX1, headTop, HAIR)
159	hspan(headX0, headX1, headTop + 1, HAIR)
160	if hair in ["spikes", "mohawk"]:
161	let
162	mohawk = hair == "mohawk"
163	start = headX0 + (if mohawk: headW div 2 - 1 else: 0)
164	stop = if mohawk: headX0 + headW div 2 else: headX1
165	step = if mohawk: 1 else: 2
166	var x = start
167	while x <= stop:
168	put(x, headTop - 1, HAIR)
169	x += step
170	if hair in ["bob", "long", "curls"]:
171	put(headX0, headTop + 2, HAIR)
172	put(headX1, headTop + 2, HAIR)
173	put(headX0, headTop + 3, HAIR)
174	put(headX1, headTop + 3, HAIR)
175	if hair == "long":
176	put(headX0, headTop + 4, HAIR)
177	put(headX1, headTop + 4, HAIR)
178	if hair == "bun":
179	put(W div 2, headTop - 1, HAIR)
180
181	# face (not shown when facing north)
182	if facing != fNorth:
183	let
184	eyeY = headTop + 4
185	eyes = t["eye_pixels"]
186	mid = W div 2
187	eyeL = case facing
188	of fEast: mid
189	of fWest: headX0 + 1
190	else: headX0 + 2
191	eyeR = case facing
192	of fEast: headX1 - 1
193	of fWest: mid - 1
194	else: headX1 - 2
195	if eyes == "visor":
196	hspan(eyeL, eyeR, eyeY, ACCENT)
197	else:
198	put(eyeL, eyeY, INK)
199	if eyes != "wink":
200	put(eyeR, eyeY, INK)
201	if eyes == "wide":
202	put(eyeL, eyeY - 1, WHITE)
203	put(eyeR, eyeY - 1, WHITE)
204	elif hair != "bald":
205	# back of head is hair
206	for y in headTop ..< 9:
207	hspan(headX0, headX1, y, HAIR)
208
209	# torso
210	for y in 10 ..< 18:
211	hspan(bodyX0, bodyX1, y, SHIRT)
212	# accent stripe
213	hspan(bodyX0, bodyX1, 13, ACCENT)
214
215	# arms (swing with walk frame)
216	let swing = case frame
217	of 0: 0
218	of 1: 1
219	else: -1
220	put(bodyX0 - 1, 11 + swing, SKIN)
221	put(bodyX0 - 1, 12 + swing, SKIN)
222	put(bodyX1 + 1, 11 - swing, SKIN)
223	put(bodyX1 + 1, 12 - swing, SKIN)
224
225	# legs
226	let
227	legW = max(2, bodyW div 2 - 1)
228	gap = case frame
229	of 0: 2
230	of 1: 4
231	else: 0
232	legL0 = W div 2 - gap div 2 - legW
233	legR0 = W div 2 + int(ceil(float(gap) / 2.0))
234	for y in 18 ..< 22:
235	hspan(legL0, legL0 + legW - 1, y, PANTS)
236	hspan(legR0, legR0 + legW - 1, y, PANTS)
237	for y in 22 ..< 24:
238	hspan(legL0, legL0 + legW - 1, y, SHOE)
239	hspan(legR0, legR0 + legW - 1, y, SHOE)
240
241	# accessory
242	case acc
243	of "hat":
244	hspan(headX0 - 1, headX1 + 1, headTop, ACCENT)
245	hspan(headX0, headX1, headTop - 1, ACCENT)
246	of "antenna":
247	put(W div 2, headTop - 1, INK)
248	put(W div 2, headTop - 2, ACCENT)
249	of "scarf":
250	hspan(bodyX0, bodyX1, 10, ACCENT)
251	of "glasses":
252	if facing != fNorth:
253	hspan(headX0 + 1, headX1 - 1, headTop + 4, INK)
254	of "headphones":
255	put(headX0 - 1, headTop + 3, ACCENT)
256	put(headX1 + 1, headTop + 3, ACCENT)
257	of "flower":
258	put(headX1, headTop + 1, ACCENT)
259	of "badge":
260	put(bodyX0 + 1, 11, ACCENT)
261	else: discard
262
263	Sprite(width: W, height: H, pixels: px,
264	palette: @["transparent", t["skin_palette"], t["hair_palette"],
265	t["shirt_jacket"], t["pants_skirt"], t["shoes"],
266	"#14141c", # outline/eyes
267	t["accent_palette"], "#ffffff"])
268
269	func spriteHash*(av: Avatar): string =
270	## Deterministic content hash over all four facings — conformance fixture value.
271	var bs: seq[byte]
272	for facing in [fSouth, fNorth, fEast, fWest]:
273	let s = renderSpritePixels(av, facing, 0)
274	for p in s.pixels:
275	bs.add byte(p and 255)
276	for color in s.palette:
277	for ch in color:
278	bs.add byte(ch)
279	toHex(digest(bs))