1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
|
Entities = {
Player = 0,
Sword = 1,
Enemy = 2
}
States = {
Walk = "walk",
Idle = "idle"
}
_id = 0
function _next_id()
i = _id
_id += 1
return i
end
Entity = {}
Entity.__index = Entity
function Entity:b_add_state(name, state)
if self.states == nil then self.states = {} end
self.states[name] = state
if self.state == nil then self.state = name end
return self
end
function Entity:b_state(name)
assert(self.states[name] != nil)
self.state = name
return self
end
function Entity:b_render_order(ord)
self.render_order = ord
return self
end
function Entity:b_position(vec)
self.position = vec2(vec)
return self
end
function Entity:b_sprite_position(vec)
self.sprite_position = vec2(vec)
return self
end
function Entity:b_type(entity_type)
self.entity_type = type
return self
end
function Entity:b_equipped(equipped)
self.equipped = equipped
return self
end
function Entity:b_collidable()
self.collision = true
return self
end
function Entity:transition_to(state_name)
if self:transition(self.state, state_name) then
self.state = state_name
self.state_stopwatch = 0
end
return self
end
function Entity:transition(from, to)
if from == States.Walk and to == States.Idle or to == States.Idle and from == States.Walk then
return true
end
return false
end
function Entity:update(dt)
if self.state_stopwatch == nil then
self.state_stopwatch = 0
end
self.state_stopwatch += dt
self:integrate(dt)
self:update_sprite_position()
self:update_line_of_sight()
if (self.velocity.x == 0 and self.velocity.x == self.velocity.y) then
self:transition_to(States.Idle)
else
self:transition_to(States.Walk)
end
if (self.equipped != nil) then
parent = self
foreach(self.equipped, function (e) e:equipped_from(parent) end)
end
end
function Entity:update_line_of_sight()
nv = self.velocity:apply(normalize_scalar)
if nv.y != 0 then self.line_of_sight = vec2(0, nv.y)
elseif nv.x != 0 then self.line_of_sight = vec2(nv.x, 0)
else self.line_of_sight = vec2(0, 0) end
end
-- prevent cobblestoning during non-manhattan movement by "lagging" the sprite
-- behind the actual physical position
function Entity:update_sprite_position()
if self.sprite_position == nil then return end
-- step in only x or y. trivial
if self.velocity == nil or self.velocity.y == 0 or self.velocity.x == 0 then
self.sprite_position.x = self.position.x
self.sprite_position.y = self.position.y
return
end
dpos = self.position - self.sprite_position
dx, dy = dpos.x, dpos.y
adx, ady = abs(dx), abs(dy)
yslow = abs(self.velocity.y) < abs(self.velocity.x)
xslow = abs(self.velocity.x) <= abs(self.velocity.y)
pushx, pushy = false, false
jerkdelta = 1
if adx >= jerkdelta and xslow and ady >= 1 then
pushx, pushy = true, true
elseif ady >= jerkdelta and yslow and adx >= 1 then
pushx, pushy = true, true
elseif xslow and ady >= 1 then
pushy = true
elseif yslow and adx >= 1 then
pushx = true
end
if pushx then
func = flr
if dx < 0 then func = ceil end
self.sprite_position.x += func(dx)
end
if pushy then
func = flr
if dy < 0 then func = ceil end
self.sprite_position.y += func(dy)
end
return self
end
function Entity:integrate(dt)
if (self.velocity != nil) then
self.position = self.position + (self.velocity * dt)
end
end
_equip_distance = 6
function Entity:equipped_from(parent)
self.line_of_sight = vec2(parent.line_of_sight)
offset = (parent.line_of_sight * _equip_distance)
self.position = parent.position + offset
self.sprite_position = parent.sprite_position + offset
end
function _get_frame(anim, t)
len = #anim.seq
frames_passed = (t / anim.dt)
idx = flr(1 + (frames_passed % len))
return anim.seq[idx]
end
_animation_keys = {"neg", "", "pos"}
function _get_animation_key(line_of_sight)
n_line_of_sight = line_of_sight:apply(normalize_scalar)
if n_line_of_sight.y ~= 0 then
return _animation_keys[n_line_of_sight.y + 2] .. "_y"
end
return _animation_keys[n_line_of_sight.x + 2] .. "_x"
end
function Entity:render()
pos = self.sprite_position or self.position
animation = self.states[self.state].animation
if (animation == nil) then return end
key = _get_animation_key(self.line_of_sight)
animation = animation[key] or animation
assert(animation[key])
frame = _get_frame(animation.sequence, self.state_t)
reflection = animation.reflection or vec2(false, false)
spr(
frame,
entity.sprite_position.x, entity.sprite_position.y,
1, 1,
reflection.x, reflection.y
)
end
function entity()
id = _next_id()
World.add(setmetatable(
{
id = id,
position = vec2(0,0),
velocity = vec2(0,0),
collision = false
}, Entity
))
return World[id]
end
|
