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package demonchime
import "core:math"
import "core:math/linalg"
import "fw"
Tail :: struct($N: int) {
points: [N]Vec2,
point_max_dist: f32,
point_rad: f32,
color_start: Color,
color_end: Color,
}
set_tail_position :: proc(tail: ^Tail($N), pos: Vec2, dt: f32) {
tail.points[0] = pos
for i in 1..<len(tail.points) {
prev := tail.points[i - 1]
cur := &tail.points[i]
cur.y += 50 * dt
dist := linalg.length2(prev - cur^)
if dist > tail.point_max_dist*tail.point_max_dist {
dir := linalg.normalize0(cur^ - prev)
cur^ = prev + dir * (tail.point_max_dist - 1)
}
}
}
draw_tail :: proc(tail: Tail($N)) {
for point, i in tail.points {
size := Vec2{tail.point_rad*2, tail.point_rad*2}
fw.draw_rect(
point - size * 0.5,
size,
color = linalg.lerp(
tail.color_start,
tail.color_end,
f32(i)/len(tail.points),
),
)
}
}
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