overte/interface/src/ParticleSystem.cpp
2013-07-12 18:55:42 -07:00

325 lines
10 KiB
C++

//
// ParticleSystem.cpp
// hifi
//
// Created by Jeffrey on July 10, 2013
//
#include <glm/glm.hpp>
#include "InterfaceConfig.h"
#include <SharedUtil.h>
#include "ParticleSystem.h"
#include "Application.h"
const float DEFAULT_PARTICLE_BOUNCE = 1.0f;
const float DEFAULT_PARTICLE_AIR_FRICTION = 2.0f;
const float DEFAULT_PARTICLE_JITTER = 0.05f;
const float DEFAULT_PARTICLE_GRAVITY = 0.05f;
ParticleSystem::ParticleSystem() {
_timer = 0.0f;
_numEmitters = 0;
_gravity = DEFAULT_PARTICLE_GRAVITY;
_bounce = DEFAULT_PARTICLE_BOUNCE;
_airFriction = DEFAULT_PARTICLE_AIR_FRICTION;
_jitter = DEFAULT_PARTICLE_JITTER;
_emitterAttraction = 0.0f;
_tornadoForce = 0.0f;
_neighborAttraction = 0.0f;
_neighborRepulsion = 0.0f;
_collisionSphereRadius = 0.0f;
_collisionSpherePosition = glm::vec3(0.0f, 0.0f, 0.0f);
_numParticles = 0;
_usingCollisionSphere = false;
_upDirection = glm::vec3(0.0f, 1.0f, 0.0f); // default
for (unsigned int e = 0; e < MAX_EMITTERS; e++) {
_emitter[e].position = glm::vec3(0.0f, 0.0f, 0.0f);
_emitter[e].rotation = glm::quat();
_emitter[e].right = IDENTITY_RIGHT;
_emitter[e].up = IDENTITY_UP;
_emitter[e].front = IDENTITY_FRONT;
};
for (unsigned int p = 0; p < MAX_PARTICLES; p++) {
_particle[p].alive = false;
_particle[p].age = 0.0f;
_particle[p].lifespan = 0.0f;
_particle[p].radius = 0.0f;
_particle[p].emitterIndex = 0;
_particle[p].position = glm::vec3(0.0f, 0.0f, 0.0f);
_particle[p].velocity = glm::vec3(0.0f, 0.0f, 0.0f);
}
}
int ParticleSystem::addEmitter() {
_numEmitters ++;
if (_numEmitters > MAX_EMITTERS) {
return -1;
}
return _numEmitters - 1;
}
void ParticleSystem::simulate(float deltaTime) {
// update emitters
for (unsigned int e = 0; e < _numEmitters; e++) {
updateEmitter(e, deltaTime);
}
// update particles
for (unsigned int p = 0; p < _numParticles; p++) {
if (_particle[p].alive) {
updateParticle(p, deltaTime);
}
}
}
void ParticleSystem::updateEmitter(int e, float deltaTime) {
_emitter[e].front = _emitter[e].rotation * IDENTITY_FRONT;
_emitter[e].right = _emitter[e].rotation * IDENTITY_RIGHT;
_emitter[e].up = _emitter[e].rotation * IDENTITY_UP;
}
void ParticleSystem::emitParticlesNow(int e, int num, float radius, glm::vec4 color, glm::vec3 velocity, float lifespan) {
for (unsigned int p = 0; p < num; p++) {
createParticle(_emitter[e].position, velocity, radius, color, lifespan);
}
}
void ParticleSystem::createParticle(glm::vec3 position, glm::vec3 velocity, float radius, glm::vec4 color, float lifespan) {
for (unsigned int p = 0; p < MAX_PARTICLES; p++) {
if (!_particle[p].alive) {
_particle[p].lifespan = lifespan;
_particle[p].alive = true;
_particle[p].age = 0.0f;
_particle[p].position = position;
_particle[p].velocity = velocity;
_particle[p].radius = radius;
_particle[p].color = color;
_numParticles ++;
assert(_numParticles <= MAX_PARTICLES);
return;
}
}
}
void ParticleSystem::killParticle(int p) {
assert( p >= 0);
assert( p < MAX_PARTICLES);
assert( _numParticles > 0);
_particle[p].alive = false;
_numParticles --;
}
void ParticleSystem::setOrangeBlueColorPalette() {
for (unsigned int p = 0; p < _numParticles; p++) {
float radian = ((float)p / (float)_numParticles) * PI_TIMES_TWO;
float wave = sinf(radian);
float red = 0.5f + 0.5f * wave;
float green = 0.3f + 0.3f * wave;
float blue = 0.2f - 0.2f * wave;
float alpha = 1.0f;
_particle[p].color = glm::vec4(red, green, blue, alpha);
}
}
void ParticleSystem::runSpecialEffectsTest(float deltaTime) {
_timer += deltaTime;
glm::vec3 tilt = glm::vec3
(
30.0f * sinf( _timer * 0.55f ),
0.0f,
30.0f * cosf( _timer * 0.75f )
);
_emitter[0].rotation = glm::quat(glm::radians(tilt));
_gravity = 0.0f + DEFAULT_PARTICLE_GRAVITY * sinf( _timer * 0.52f );
_airFriction = (DEFAULT_PARTICLE_AIR_FRICTION + 0.5f) + 2.0f * sinf( _timer * 0.32f );
_jitter = DEFAULT_PARTICLE_JITTER + DEFAULT_PARTICLE_JITTER * sinf( _timer * 0.42f );
_emitterAttraction = 0.015f + 0.015f * cosf( _timer * 0.6f );
_tornadoForce = 0.0f + 0.03f * sinf( _timer * 0.7f );
_neighborAttraction = 0.1f + 0.1f * cosf( _timer * 0.8f );
_neighborRepulsion = 0.2f + 0.2f * sinf( _timer * 0.4f );
if (_gravity < 0.0f) {
_gravity = 0.0f;
}
}
void ParticleSystem::updateParticle(int p, float deltaTime) {
_particle[p].age += deltaTime;
if (_particle[p].age > _particle[p].lifespan) {
killParticle(p);
}
// apply random jitter
_particle[p].velocity +=
glm::vec3
(
-_jitter * ONE_HALF + _jitter * randFloat(),
-_jitter * ONE_HALF + _jitter * randFloat(),
-_jitter * ONE_HALF + _jitter * randFloat()
) * deltaTime;
// apply attraction to home position
glm::vec3 vectorToHome = _emitter[_particle[p].emitterIndex].position - _particle[p].position;
_particle[p].velocity += vectorToHome * _emitterAttraction * deltaTime;
// apply neighbor attraction
int neighbor = p + 1;
if (neighbor == _numParticles ) {
neighbor = 0;
}
glm::vec3 vectorToNeighbor = _particle[p].position - _particle[neighbor].position;
_particle[p].velocity -= vectorToNeighbor * _neighborAttraction * deltaTime;
float distanceToNeighbor = glm::length(vectorToNeighbor);
if (distanceToNeighbor > 0.0f) {
_particle[neighbor].velocity += (vectorToNeighbor / ( 1.0f + distanceToNeighbor * distanceToNeighbor)) * _neighborRepulsion * deltaTime;
}
// apply tornado force
glm::vec3 tornadoDirection = glm::cross(vectorToHome, _emitter[_particle[p].emitterIndex].up);
_particle[p].velocity += tornadoDirection * _tornadoForce * deltaTime;
// apply air friction
float drag = 1.0 - _airFriction * deltaTime;
if (drag < 0.0f) {
_particle[p].velocity = glm::vec3(0.0f, 0.0f, 0.0f);
} else {
_particle[p].velocity *= drag;
}
// apply gravity
_particle[p].velocity -= _upDirection * _gravity * deltaTime;
// update position by velocity
_particle[p].position += _particle[p].velocity;
// collision with ground
if (_particle[p].position.y < _particle[p].radius) {
_particle[p].position.y = _particle[p].radius;
if (_particle[p].velocity.y < 0.0f) {
_particle[p].velocity.y *= -_bounce;
}
}
// collision with sphere
if (_usingCollisionSphere) {
glm::vec3 vectorToSphereCenter = _collisionSpherePosition - _particle[p].position;
float distanceToSphereCenter = glm::length(vectorToSphereCenter);
float combinedRadius = _collisionSphereRadius + _particle[p].radius;
if (distanceToSphereCenter < combinedRadius) {
if (distanceToSphereCenter > 0.0f){
glm::vec3 directionToSphereCenter = vectorToSphereCenter / distanceToSphereCenter;
_particle[p].position = _collisionSpherePosition - directionToSphereCenter * combinedRadius;
}
}
}
}
void ParticleSystem::setCollisionSphere(glm::vec3 position, float radius) {
_usingCollisionSphere = true;
_collisionSpherePosition = position;
_collisionSphereRadius = radius;
}
void ParticleSystem::render() {
// render the emitters
for (unsigned int e = 0; e < _numEmitters; e++) {
renderEmitter(e, 0.2f);
};
// render the particles
for (unsigned int p = 0; p < _numParticles; p++) {
if (_particle[p].alive) {
renderParticle(p);
}
}
}
void ParticleSystem::renderParticle(int p) {
glColor4f(_particle[p].color.r, _particle[p].color.g, _particle[p].color.b, _particle[p].color.a );
glPushMatrix();
glTranslatef(_particle[p].position.x, _particle[p].position.y, _particle[p].position.z);
glutSolidSphere(_particle[p].radius, 6, 6);
glPopMatrix();
// render velocity lines
glColor4f( _particle[p].color.x, _particle[p].color.y, _particle[p].color.z, 0.5f);
glm::vec3 end = _particle[p].position - _particle[p].velocity * 2.0f;
glBegin(GL_LINES);
glVertex3f(_particle[p].position.x, _particle[p].position.y, _particle[p].position.z);
glVertex3f(end.x, end.y, end.z);
glEnd();
}
void ParticleSystem::renderEmitter(int e, float size) {
glm::vec3 r = _emitter[e].right * size;
glm::vec3 u = _emitter[e].up * size;
glm::vec3 f = _emitter[e].front * size;
glLineWidth(2.0f);
glColor3f(0.8f, 0.4, 0.4);
glBegin(GL_LINES);
glVertex3f(_emitter[e].position.x, _emitter[e].position.y, _emitter[e].position.z);
glVertex3f(_emitter[e].position.x + r.x, _emitter[e].position.y + r.y, _emitter[e].position.z + r.z);
glEnd();
glColor3f(0.4f, 0.8, 0.4);
glBegin(GL_LINES);
glVertex3f(_emitter[e].position.x, _emitter[e].position.y, _emitter[e].position.z);
glVertex3f(_emitter[e].position.x + u.x, _emitter[e].position.y + u.y, _emitter[e].position.z + u.z);
glEnd();
glColor3f(0.4f, 0.4, 0.8);
glBegin(GL_LINES);
glVertex3f(_emitter[e].position.x, _emitter[e].position.y, _emitter[e].position.z);
glVertex3f(_emitter[e].position.x + f.x, _emitter[e].position.y + f.y, _emitter[e].position.z + f.z);
glEnd();
}