pxl8/src/gfx/pxl8_particles.c

323 lines
8.6 KiB
C

#include "pxl8_particles.h"
#include <stdlib.h>
#include "pxl8_gfx.h"
#include "pxl8_mem.h"
#include "pxl8_gfx2d.h"
#include "pxl8_palette.h"
#include "pxl8_rng.h"
struct pxl8_particles {
pxl8_particle* particles;
pxl8_palette* palette;
pxl8_rng* rng;
u32 alive_count;
u32 count;
u32 max_count;
f32 x, y;
f32 spread_x, spread_y;
f32 drag;
f32 gravity_x, gravity_y;
f32 turbulence;
f32 spawn_rate;
f32 spawn_timer;
u8 color_min, color_max;
f32 life_min, life_max;
f32 size_min, size_max;
f32 vx_min, vx_max, vy_min, vy_max;
pxl8_particle_render_fn render_fn;
pxl8_particle_spawn_fn spawn_fn;
pxl8_particle_update_fn update_fn;
void* userdata;
};
pxl8_particles* pxl8_particles_create(u32 max_count, pxl8_rng* rng) {
pxl8_particles* ps = pxl8_calloc(1, sizeof(pxl8_particles));
if (!ps) return NULL;
ps->particles = pxl8_calloc(max_count, sizeof(pxl8_particle));
if (!ps->particles) {
pxl8_free(ps);
return NULL;
}
ps->rng = rng;
ps->max_count = max_count;
ps->drag = 0.98f;
ps->gravity_y = 100.0f;
ps->spawn_rate = 10.0f;
ps->color_min = ps->color_max = 15;
ps->life_min = ps->life_max = 1.0f;
ps->size_min = ps->size_max = 1.0f;
return ps;
}
void pxl8_particles_destroy(pxl8_particles* ps) {
if (!ps) return;
pxl8_free(ps->particles);
pxl8_free(ps);
}
void pxl8_particles_clear(pxl8_particles* ps) {
if (!ps || !ps->particles) return;
for (u32 i = 0; i < ps->max_count; i++) {
ps->particles[i].life = 0;
ps->particles[i].flags = 0;
}
ps->alive_count = 0;
ps->spawn_timer = 0;
}
void pxl8_particles_emit(pxl8_particles* ps, u32 count) {
if (!ps || !ps->particles) return;
for (u32 i = 0; i < count && ps->alive_count < ps->max_count; i++) {
for (u32 j = 0; j < ps->max_count; j++) {
if (ps->particles[j].life <= 0) {
pxl8_particle* p = &ps->particles[j];
f32 life = ps->life_min + pxl8_rng_f32(ps->rng) * (ps->life_max - ps->life_min);
p->life = life;
p->max_life = life;
p->x = ps->x + (pxl8_rng_f32(ps->rng) - 0.5f) * ps->spread_x;
p->y = ps->y + (pxl8_rng_f32(ps->rng) - 0.5f) * ps->spread_y;
p->z = 0;
p->vx = ps->vx_min + pxl8_rng_f32(ps->rng) * (ps->vx_max - ps->vx_min);
p->vy = ps->vy_min + pxl8_rng_f32(ps->rng) * (ps->vy_max - ps->vy_min);
p->vz = 0;
p->ax = ps->gravity_x;
p->ay = ps->gravity_y;
p->az = 0;
u8 ramp_range = ps->color_max - ps->color_min + 1;
u8 ramp_pos = ps->color_min + (pxl8_rng_next(ps->rng) % ramp_range);
u8 color = ps->palette
? pxl8_palette_ramp_index(ps->palette, ramp_pos)
: ramp_pos;
p->color = p->start_color = p->end_color = color;
p->size = ps->size_min + pxl8_rng_f32(ps->rng) * (ps->size_max - ps->size_min);
p->angle = 0;
p->spin = 0;
p->flags = 1;
if (ps->spawn_fn) {
ps->spawn_fn(ps, p);
}
ps->alive_count++;
break;
}
}
}
}
void pxl8_particles_render(pxl8_particles* ps, pxl8_gfx* gfx) {
if (!ps || !ps->particles || !gfx) return;
for (u32 i = 0; i < ps->max_count; i++) {
pxl8_particle* p = &ps->particles[i];
if (p->life > 0 && p->flags) {
if (ps->render_fn) {
ps->render_fn(gfx, p, ps->userdata);
} else {
i32 x = (i32)p->x;
i32 y = (i32)p->y;
if (x >= 0 && x < pxl8_gfx_get_width(gfx) && y >= 0 && y < pxl8_gfx_get_height(gfx)) {
pxl8_2d_pixel(gfx, x, y, p->color);
}
}
}
}
}
void pxl8_particles_update(pxl8_particles* ps, f32 dt) {
if (!ps || !ps->particles) return;
if (ps->spawn_rate > 0.0f) {
ps->spawn_timer += dt;
f32 spawn_interval = 1.0f / ps->spawn_rate;
u32 max_spawns_per_frame = ps->max_count / 10;
if (max_spawns_per_frame < 1) max_spawns_per_frame = 1;
u32 spawn_count = 0;
while (ps->spawn_timer >= spawn_interval && spawn_count < max_spawns_per_frame) {
pxl8_particles_emit(ps, 1);
ps->spawn_timer -= spawn_interval;
spawn_count++;
}
}
for (u32 i = 0; i < ps->max_count; i++) {
pxl8_particle* p = &ps->particles[i];
if (p->life > 0) {
if (ps->update_fn) {
ps->update_fn(p, dt, ps->userdata);
} else {
p->vx += p->ax * dt;
p->vy += p->ay * dt;
p->vz += p->az * dt;
p->vx *= ps->drag;
p->vy *= ps->drag;
p->vz *= ps->drag;
p->x += p->vx * dt;
p->y += p->vy * dt;
p->z += p->vz * dt;
p->angle += p->spin * dt;
}
p->life -= dt / p->max_life;
if (p->life <= 0) {
p->flags = 0;
ps->alive_count--;
}
}
}
}
u32 pxl8_particles_count(const pxl8_particles* ps) {
return ps ? ps->alive_count : 0;
}
u32 pxl8_particles_max_count(const pxl8_particles* ps) {
return ps ? ps->max_count : 0;
}
pxl8_particle* pxl8_particles_get(pxl8_particles* ps, u32 index) {
if (!ps || index >= ps->max_count) return NULL;
return &ps->particles[index];
}
pxl8_rng* pxl8_particles_rng(pxl8_particles* ps) {
return ps ? ps->rng : NULL;
}
f32 pxl8_particles_get_drag(const pxl8_particles* ps) {
return ps ? ps->drag : 0.0f;
}
f32 pxl8_particles_get_gravity_x(const pxl8_particles* ps) {
return ps ? ps->gravity_x : 0.0f;
}
f32 pxl8_particles_get_gravity_y(const pxl8_particles* ps) {
return ps ? ps->gravity_y : 0.0f;
}
f32 pxl8_particles_get_spawn_rate(const pxl8_particles* ps) {
return ps ? ps->spawn_rate : 0.0f;
}
f32 pxl8_particles_get_spread_x(const pxl8_particles* ps) {
return ps ? ps->spread_x : 0.0f;
}
f32 pxl8_particles_get_spread_y(const pxl8_particles* ps) {
return ps ? ps->spread_y : 0.0f;
}
f32 pxl8_particles_get_turbulence(const pxl8_particles* ps) {
return ps ? ps->turbulence : 0.0f;
}
void* pxl8_particles_get_userdata(const pxl8_particles* ps) {
return ps ? ps->userdata : NULL;
}
f32 pxl8_particles_get_x(const pxl8_particles* ps) {
return ps ? ps->x : 0.0f;
}
f32 pxl8_particles_get_y(const pxl8_particles* ps) {
return ps ? ps->y : 0.0f;
}
void pxl8_particles_set_colors(pxl8_particles* ps, u8 color_min, u8 color_max) {
if (!ps) return;
ps->color_min = color_min;
ps->color_max = color_max;
}
void pxl8_particles_set_drag(pxl8_particles* ps, f32 drag) {
if (ps) ps->drag = drag;
}
void pxl8_particles_set_gravity(pxl8_particles* ps, f32 gx, f32 gy) {
if (!ps) return;
ps->gravity_x = gx;
ps->gravity_y = gy;
}
void pxl8_particles_set_life(pxl8_particles* ps, f32 life_min, f32 life_max) {
if (!ps) return;
ps->life_min = life_min;
ps->life_max = life_max;
}
void pxl8_particles_set_palette(pxl8_particles* ps, pxl8_palette* palette) {
if (ps) ps->palette = palette;
}
void pxl8_particles_set_position(pxl8_particles* ps, f32 x, f32 y) {
if (!ps) return;
ps->x = x;
ps->y = y;
}
void pxl8_particles_set_render_fn(pxl8_particles* ps, pxl8_particle_render_fn fn) {
if (ps) ps->render_fn = fn;
}
void pxl8_particles_set_size(pxl8_particles* ps, f32 size_min, f32 size_max) {
if (!ps) return;
ps->size_min = size_min;
ps->size_max = size_max;
}
void pxl8_particles_set_spawn_fn(pxl8_particles* ps, pxl8_particle_spawn_fn fn) {
if (ps) ps->spawn_fn = fn;
}
void pxl8_particles_set_spawn_rate(pxl8_particles* ps, f32 rate) {
if (ps) ps->spawn_rate = rate;
}
void pxl8_particles_set_spread(pxl8_particles* ps, f32 spread_x, f32 spread_y) {
if (!ps) return;
ps->spread_x = spread_x;
ps->spread_y = spread_y;
}
void pxl8_particles_set_turbulence(pxl8_particles* ps, f32 turbulence) {
if (ps) ps->turbulence = turbulence;
}
void pxl8_particles_set_update_fn(pxl8_particles* ps, pxl8_particle_update_fn fn) {
if (ps) ps->update_fn = fn;
}
void pxl8_particles_set_userdata(pxl8_particles* ps, void* userdata) {
if (ps) ps->userdata = userdata;
}
void pxl8_particles_set_velocity(pxl8_particles* ps, f32 vx_min, f32 vx_max, f32 vy_min, f32 vy_max) {
if (!ps) return;
ps->vx_min = vx_min;
ps->vx_max = vx_max;
ps->vy_min = vy_min;
ps->vy_max = vy_max;
}