v/examples/sokol/particles/modules/particle/system.v

117 lines
2.2 KiB
V

// Copyright(C) 2019 Lars Pontoppidan. All rights reserved.
// Use of this source code is governed by an MIT license file distributed with this software package
module particle
import particle.vec2
import rand
import sokol.sgl
pub struct SystemConfig {
pool int
}
pub struct System {
width int
height int
mut:
pool []&Particle
bin []&Particle
}
pub fn (mut s System) init(sc SystemConfig) {
unsafe { s.pool.flags.set(.noslices | .noshrink) }
unsafe { s.bin.flags.set(.noslices | .noshrink) }
for i := 0; i < sc.pool; i++ {
p := new(vec2.Vec2{f32(s.width) * 0.5, f32(s.height) * 0.5})
s.bin << p
}
}
pub fn (mut s System) update(dt f64) {
mut p := &Particle(0)
mut moved := 0
for i := 0; i < s.pool.len; i++ {
p = s.pool[i]
p.update(dt)
if p.is_dead() {
s.bin << p
s.pool.delete(i)
moved++
}
}
$if trace_moves_spool_to_sbin ? {
if moved != 0 {
eprintln('${moved:4} particles s.pool -> s.bin')
}
}
}
pub fn (s System) draw() {
sgl.begin_quads()
for p in s.pool {
p.draw()
}
sgl.end()
}
pub fn (mut s System) reset() {
for i in 0 .. s.pool.len {
mut p := s.pool[i]
p.reset()
p.life_time = 0
}
for i in 0 .. s.bin.len {
mut p := s.pool[i]
p.reset()
p.life_time = 0
}
}
pub fn (mut s System) explode(x f32, y f32) {
mut reserve := 500
center := vec2.Vec2{x, y}
mut p := &Particle(0)
mut moved := 0
for i := 0; i < s.bin.len && reserve > 0; i++ {
p = s.bin[i]
p.reset()
p.location.from(center)
p.acceleration = vec2.Vec2{rand.f32_in_range(-0.5, 0.5) or { -0.5 }, rand.f32_in_range(-0.5,
0.5) or { -0.5 }}
p.velocity = vec2.Vec2{rand.f32_in_range(-0.5, 0.5) or { -0.5 }, rand.f32_in_range(-0.5,
0.5) or { -0.5 }}
p.life_time = rand.f64_in_range(500, 2000) or { 500 }
s.pool << p
s.bin.delete(i)
moved++
reserve--
}
$if trace_moves_sbin_to_spool ? {
if moved != 0 {
eprintln('${moved:4} particles s.bin -> s.pool')
}
}
}
pub fn (mut s System) free() {
for p in s.pool {
if unsafe { p == 0 } {
print(ptr_str(p) + ' ouch')
continue
}
unsafe { free(p) }
}
s.pool.clear()
for p in s.bin {
if unsafe { p == 0 } {
print(ptr_str(p) + ' ouch')
continue
}
unsafe {
// println('Freeing from bin')
free(p)
}
}
s.bin.clear()
}