diff options
Diffstat (limited to 'src/crepe/system/ParticleSystem.cpp')
| -rw-r--r-- | src/crepe/system/ParticleSystem.cpp | 141 |
1 files changed, 100 insertions, 41 deletions
diff --git a/src/crepe/system/ParticleSystem.cpp b/src/crepe/system/ParticleSystem.cpp index 397b586..35a1d41 100644 --- a/src/crepe/system/ParticleSystem.cpp +++ b/src/crepe/system/ParticleSystem.cpp @@ -1,62 +1,121 @@ +#include <chrono> #include <cmath> +#include <cstdlib> #include <ctime> -#include "../ComponentManager.h" #include "../api/ParticleEmitter.h" +#include "../api/Transform.h" +#include "../manager/ComponentManager.h" +#include "../manager/LoopTimerManager.h" #include "ParticleSystem.h" using namespace crepe; -ParticleSystem::ParticleSystem() : elapsed_time(0.0f) {} - void ParticleSystem::update() { - ComponentManager & mgr = ComponentManager::get_instance(); - std::vector<std::reference_wrapper<ParticleEmitter>> emitters - = mgr.get_components_by_type<ParticleEmitter>(); - float delta_time = 0.10; + // Get all emitters + const Mediator & mediator = this->mediator; + LoopTimerManager & loop_timer = mediator.loop_timer; + ComponentManager & mgr = mediator.component_manager; + float dt = loop_timer.get_scaled_fixed_delta_time().count(); + + RefVector<ParticleEmitter> emitters = mgr.get_components_by_type<ParticleEmitter>(); + for (ParticleEmitter & emitter : emitters) { - float update_amount = 1 / static_cast<float>(emitter.emission_rate); - for (float i = 0; i < delta_time; i += update_amount) { - emit_particle(emitter); + // Get transform linked to emitter + const Transform & transform + = mgr.get_components_by_id<Transform>(emitter.game_object_id).front().get(); + + // Emit particles based on emission_rate + emitter.spawn_accumulator += emitter.data.emission_rate * dt; + while (emitter.spawn_accumulator >= 1.0) { + this->emit_particle(emitter, transform); + emitter.spawn_accumulator -= 1.0; } - for (size_t j = 0; j < emitter.particles.size(); j++) { - if (emitter.particles[j].active) { - emitter.particles[j].update(delta_time); + + // Update all particles + for (Particle & particle : emitter.particles) { + if (particle.active) { + particle.update(dt); } } + + // Check if within boundary + this->check_bounds(emitter, transform); } } -void ParticleSystem::emit_particle(ParticleEmitter & emitter) { - Position initial_position = {emitter.position.x, emitter.position.y}; - float random_angle = 0.0f; - if (emitter.max_angle < emitter.min_angle) { - random_angle = ((emitter.min_angle - + (std::rand() - % (static_cast<uint32_t>(emitter.max_angle + 360 - - emitter.min_angle + 1)))) - % 360); - } else { - random_angle = emitter.min_angle - + (std::rand() - % (static_cast<uint32_t>(emitter.max_angle - - emitter.min_angle + 1))); - } - float angle_in_radians = random_angle * (M_PI / 180.0f); - float random_speed_offset = (static_cast<float>(std::rand()) / RAND_MAX) - * (2 * emitter.speed_offset) - - emitter.speed_offset; - float velocity_x - = (emitter.speed + random_speed_offset) * std::cos(angle_in_radians); - float velocity_y - = (emitter.speed + random_speed_offset) * std::sin(angle_in_radians); - Position initial_velocity = {velocity_x, velocity_y}; - for (size_t i = 0; i < emitter.particles.size(); i++) { - if (!emitter.particles[i].active) { - emitter.particles[i].reset(emitter.end_lifespan, initial_position, - initial_velocity); +void ParticleSystem::emit_particle(ParticleEmitter & emitter, const Transform & transform) { + constexpr float DEG_TO_RAD = M_PI / 180.0; + + vec2 initial_position = emitter.data.offset + transform.position; + float random_angle + = this->generate_random_angle(emitter.data.min_angle, emitter.data.max_angle); + + float random_speed + = this->generate_random_speed(emitter.data.min_speed, emitter.data.max_speed); + float angle_radians = random_angle * DEG_TO_RAD; + + vec2 velocity + = {random_speed * std::cos(angle_radians), random_speed * std::sin(angle_radians)}; + + for (Particle & particle : emitter.particles) { + if (!particle.active) { + particle.reset(emitter.data.end_lifespan, initial_position, velocity, + random_angle); break; } } } + +void ParticleSystem::check_bounds(ParticleEmitter & emitter, const Transform & transform) { + vec2 offset = emitter.data.boundary.offset + transform.position + emitter.data.offset; + float half_width = emitter.data.boundary.width / 2.0; + float half_height = emitter.data.boundary.height / 2.0; + + float left = offset.x - half_width; + float right = offset.x + half_width; + float top = offset.y - half_height; + float bottom = offset.y + half_height; + + for (Particle & particle : emitter.particles) { + const vec2 & position = particle.position; + bool within_bounds = (position.x >= left && position.x <= right && position.y >= top + && position.y <= bottom); + //if not within bounds do a reset or stop velocity + if (!within_bounds) { + if (emitter.data.boundary.reset_on_exit) { + particle.active = false; + } else { + particle.velocity = {0, 0}; + if (position.x < left) particle.position.x = left; + else if (position.x > right) particle.position.x = right; + if (position.y < top) particle.position.y = top; + else if (position.y > bottom) particle.position.y = bottom; + } + } + } +} + +float ParticleSystem::generate_random_angle(float min_angle, float max_angle) const { + if (min_angle == max_angle) { + return min_angle; + } else if (min_angle < max_angle) { + return min_angle + + static_cast<float>(std::rand() % static_cast<int>(max_angle - min_angle)); + } else { + float angle_offset = (360 - min_angle) + max_angle; + float random_angle + = min_angle + static_cast<float>(std::rand() % static_cast<int>(angle_offset)); + return (random_angle >= 360) ? random_angle - 360 : random_angle; + } +} + +float ParticleSystem::generate_random_speed(float min_speed, float max_speed) const { + if (min_speed == max_speed) { + return min_speed; + } else { + return min_speed + + static_cast<float>(std::rand() % static_cast<int>(max_speed - min_speed)); + } +} |