/** * Copyright (c) 2006-2016 LOVE Development Team * * This software is provided 'as-is', without any express or implied * warranty. In no event will the authors be held liable for any damages * arising from the use of this software. * * Permission is granted to anyone to use this software for any purpose, * including commercial applications, and to alter it and redistribute it * freely, subject to the following restrictions: * * 1. The origin of this software must not be misrepresented; you must not * claim that you wrote the original software. If you use this software * in a product, an acknowledgment in the product documentation would be * appreciated but is not required. * 2. Altered source versions must be plainly marked as such, and must not be * misrepresented as being the original software. * 3. This notice may not be removed or altered from any source distribution. **/ //LOVE #include "common/config.h" #include "ParticleSystem.h" #include "common/math.h" #include "modules/math/RandomGenerator.h" // STD #include #include #include namespace love { namespace graphics { namespace { love::math::RandomGenerator rng; float calculate_variation(float inner, float outer, float var) { float low = inner - (outer/2.0f)*var; float high = inner + (outer/2.0f)*var; float r = (float) rng.random(); return low*(1-r)+high*r; } } // anonymous namespace ParticleSystem::ParticleSystem(Texture *texture, uint32 size) : pMem(nullptr) , pFree(nullptr) , pHead(nullptr) , pTail(nullptr) , texture(texture) , active(true) , insertMode(INSERT_MODE_TOP) , maxParticles(0) , activeParticles(0) , emissionRate(0) , emitCounter(0) , areaSpreadDistribution(DISTRIBUTION_NONE) , lifetime(-1) , life(0) , particleLifeMin(0) , particleLifeMax(0) , direction(0) , spread(0) , speedMin(0) , speedMax(0) , linearAccelerationMin(0, 0) , linearAccelerationMax(0, 0) , radialAccelerationMin(0) , radialAccelerationMax(0) , tangentialAccelerationMin(0) , tangentialAccelerationMax(0) , linearDampingMin(0.0f) , linearDampingMax(0.0f) , sizeVariation(0) , rotationMin(0) , rotationMax(0) , spinStart(0) , spinEnd(0) , spinVariation(0) , offset(float(texture->getWidth())*0.5f, float(texture->getHeight())*0.5f) , defaultOffset(true) , relativeRotation(false) { if (size == 0 || size > MAX_PARTICLES) throw love::Exception("Invalid ParticleSystem size."); sizes.push_back(1.0f); colors.push_back(Colorf(1.0f, 1.0f, 1.0f, 1.0f)); setBufferSize(size); } ParticleSystem::ParticleSystem(const ParticleSystem &p) : pMem(nullptr) , pFree(nullptr) , pHead(nullptr) , pTail(nullptr) , texture(p.texture) , active(p.active) , insertMode(p.insertMode) , maxParticles(p.maxParticles) , activeParticles(0) , emissionRate(p.emissionRate) , emitCounter(0.0f) , position(p.position) , prevPosition(p.prevPosition) , areaSpreadDistribution(p.areaSpreadDistribution) , areaSpread(p.areaSpread) , lifetime(p.lifetime) , life(p.lifetime) // Initialize with the maximum life time. , particleLifeMin(p.particleLifeMin) , particleLifeMax(p.particleLifeMax) , direction(p.direction) , spread(p.spread) , speedMin(p.speedMin) , speedMax(p.speedMax) , linearAccelerationMin(p.linearAccelerationMin) , linearAccelerationMax(p.linearAccelerationMax) , radialAccelerationMin(p.radialAccelerationMin) , radialAccelerationMax(p.radialAccelerationMax) , tangentialAccelerationMin(p.tangentialAccelerationMin) , tangentialAccelerationMax(p.tangentialAccelerationMax) , linearDampingMin(p.linearDampingMin) , linearDampingMax(p.linearDampingMax) , sizes(p.sizes) , sizeVariation(p.sizeVariation) , rotationMin(p.rotationMin) , rotationMax(p.rotationMax) , spinStart(p.spinStart) , spinEnd(p.spinEnd) , spinVariation(p.spinVariation) , offset(p.offset) , defaultOffset(p.defaultOffset) , colors(p.colors) , quads(p.quads) , relativeRotation(p.relativeRotation) { setBufferSize(maxParticles); } ParticleSystem::~ParticleSystem() { deleteBuffers(); } void ParticleSystem::resetOffset() { if (quads.empty()) offset = love::Vector(float(texture->getWidth())*0.5f, float(texture->getHeight())*0.5f); else { Quad::Viewport v = quads[0]->getViewport(); offset = love::Vector(v.x*0.5f, v.y*0.5f); } } void ParticleSystem::createBuffers(size_t size) { try { pFree = pMem = new Particle[size]; maxParticles = (uint32) size; } catch (std::bad_alloc &) { deleteBuffers(); throw love::Exception("Out of memory"); } } void ParticleSystem::deleteBuffers() { // Clean up for great gracefulness! delete[] pMem; pMem = nullptr; maxParticles = 0; activeParticles = 0; } void ParticleSystem::setBufferSize(uint32 size) { if (size == 0 || size > MAX_PARTICLES) throw love::Exception("Invalid buffer size"); deleteBuffers(); createBuffers(size); reset(); } uint32 ParticleSystem::getBufferSize() const { return maxParticles; } void ParticleSystem::addParticle(float t) { if (isFull()) return; // Gets a free particle and updates the allocation pointer. Particle *p = pFree++; initParticle(p, t); switch (insertMode) { default: case INSERT_MODE_TOP: insertTop(p); break; case INSERT_MODE_BOTTOM: insertBottom(p); break; case INSERT_MODE_RANDOM: insertRandom(p); break; } activeParticles++; } void ParticleSystem::initParticle(Particle *p, float t) { float min,max; // Linearly interpolate between the previous and current emitter position. love::Vector pos = prevPosition + (position - prevPosition) * t; min = particleLifeMin; max = particleLifeMax; if (min == max) p->life = min; else p->life = (float) rng.random(min, max); p->lifetime = p->life; p->position = pos; float rand_x, rand_y; switch (areaSpreadDistribution) { case DISTRIBUTION_UNIFORM: p->position.x += (float) rng.random(-areaSpread.getX(), areaSpread.getX()); p->position.y += (float) rng.random(-areaSpread.getY(), areaSpread.getY()); break; case DISTRIBUTION_NORMAL: p->position.x += (float) rng.randomNormal(areaSpread.getX()); p->position.y += (float) rng.randomNormal(areaSpread.getY()); break; case DISTRIBUTION_ELLIPSE: rand_x = (float) rng.random(-1, 1); rand_y = (float) rng.random(-1, 1); p->position.x += areaSpread.getX() * (rand_x * sqrt(1 - 0.5f*pow(rand_y, 2))); p->position.y += areaSpread.getY() * (rand_y * sqrt(1 - 0.5f*pow(rand_x, 2))); break; case DISTRIBUTION_NONE: default: break; } p->origin = pos; min = speedMin; max = speedMax; float speed = (float) rng.random(min, max); min = direction - spread/2.0f; max = direction + spread/2.0f; float dir = (float) rng.random(min, max); p->velocity = love::Vector(cosf(dir), sinf(dir)) * speed; p->linearAcceleration.x = (float) rng.random(linearAccelerationMin.x, linearAccelerationMax.x); p->linearAcceleration.y = (float) rng.random(linearAccelerationMin.y, linearAccelerationMax.y); min = radialAccelerationMin; max = radialAccelerationMax; p->radialAcceleration = (float) rng.random(min, max); min = tangentialAccelerationMin; max = tangentialAccelerationMax; p->tangentialAcceleration = (float) rng.random(min, max); min = linearDampingMin; max = linearDampingMax; p->linearDamping = (float) rng.random(min, max); p->sizeOffset = (float) rng.random(sizeVariation); // time offset for size change p->sizeIntervalSize = (1.0f - (float) rng.random(sizeVariation)) - p->sizeOffset; p->size = sizes[(size_t)(p->sizeOffset - .5f) * (sizes.size() - 1)]; min = rotationMin; max = rotationMax; p->spinStart = calculate_variation(spinStart, spinEnd, spinVariation); p->spinEnd = calculate_variation(spinEnd, spinStart, spinVariation); p->rotation = (float) rng.random(min, max); p->angle = p->rotation; if (relativeRotation) p->angle += atan2f(p->velocity.y, p->velocity.x); p->color = colors[0]; p->quadIndex = 0; } void ParticleSystem::insertTop(Particle *p) { if (pHead == nullptr) { pHead = p; p->prev = nullptr; } else { pTail->next = p; p->prev = pTail; } p->next = nullptr; pTail = p; } void ParticleSystem::insertBottom(Particle *p) { if (pTail == nullptr) { pTail = p; p->next = nullptr; } else { pHead->prev = p; p->next = pHead; } p->prev = nullptr; pHead = p; } void ParticleSystem::insertRandom(Particle *p) { // Nonuniform, but 64-bit is so large nobody will notice. Hopefully. uint64 pos = rng.rand() % ((int64) activeParticles + 1); // Special case where the particle gets inserted before the head. if (pos == activeParticles) { Particle *pA = pHead; if (pA) pA->prev = p; p->prev = nullptr; p->next = pA; pHead = p; return; } // Inserts the particle after the randomly selected particle. Particle *pA = pMem + pos; Particle *pB = pA->next; pA->next = p; if (pB) pB->prev = p; else pTail = p; p->prev = pA; p->next = pB; } ParticleSystem::Particle *ParticleSystem::removeParticle(Particle *p) { // The linked list is updated in this function and old pointers may be // invalidated. The returned pointer will inform the caller of the new // pointer to the next particle. Particle *pNext = nullptr; // Removes the particle from the linked list. if (p->prev) p->prev->next = p->next; else pHead = p->next; if (p->next) { p->next->prev = p->prev; pNext = p->next; } else pTail = p->prev; // The (in memory) last particle can now be moved into the free slot. // It will skip the moving if it happens to be the removed particle. pFree--; if (p != pFree) { *p = *pFree; if (pNext == pFree) pNext = p; if (p->prev) p->prev->next = p; else pHead = p; if (p->next) p->next->prev = p; else pTail = p; } activeParticles--; return pNext; } void ParticleSystem::setTexture(Texture *tex) { texture.set(tex); if (defaultOffset) resetOffset(); } Texture *ParticleSystem::getTexture() const { return texture.get(); } void ParticleSystem::setInsertMode(InsertMode mode) { insertMode = mode; } ParticleSystem::InsertMode ParticleSystem::getInsertMode() const { return insertMode; } void ParticleSystem::setEmissionRate(float rate) { if (rate < 0.0f) throw love::Exception("Invalid emission rate"); emissionRate = rate; // Prevent an explosion when dramatically increasing the rate emitCounter = std::min(emitCounter, 1.0f/rate); } float ParticleSystem::getEmissionRate() const { return emissionRate; } void ParticleSystem::setEmitterLifetime(float life) { this->life = lifetime = life; } float ParticleSystem::getEmitterLifetime() const { return lifetime; } void ParticleSystem::setParticleLifetime(float min, float max) { particleLifeMin = min; if (max == 0) particleLifeMax = min; else particleLifeMax = max; } void ParticleSystem::getParticleLifetime(float &min, float &max) const { min = particleLifeMin; max = particleLifeMax; } void ParticleSystem::setPosition(float x, float y) { position = love::Vector(x, y); prevPosition = position; } const love::Vector &ParticleSystem::getPosition() const { return position; } void ParticleSystem::moveTo(float x, float y) { position = love::Vector(x, y); } void ParticleSystem::setAreaSpread(AreaSpreadDistribution distribution, float x, float y) { areaSpread = love::Vector(x, y); areaSpreadDistribution = distribution; } ParticleSystem::AreaSpreadDistribution ParticleSystem::getAreaSpreadDistribution() const { return areaSpreadDistribution; } const love::Vector &ParticleSystem::getAreaSpreadParameters() const { return areaSpread; } void ParticleSystem::setDirection(float direction) { this->direction = direction; } float ParticleSystem::getDirection() const { return direction; } void ParticleSystem::setSpread(float spread) { this->spread = spread; } float ParticleSystem::getSpread() const { return spread; } void ParticleSystem::setSpeed(float speed) { speedMin = speedMax = speed; } void ParticleSystem::setSpeed(float min, float max) { speedMin = min; speedMax = max; } void ParticleSystem::getSpeed(float &min, float &max) const { min = speedMin; max = speedMax; } void ParticleSystem::setLinearAcceleration(float x, float y) { linearAccelerationMin.x = linearAccelerationMax.x = x; linearAccelerationMin.y = linearAccelerationMax.y = y; } void ParticleSystem::setLinearAcceleration(float xmin, float ymin, float xmax, float ymax) { linearAccelerationMin = love::Vector(xmin, ymin); linearAccelerationMax = love::Vector(xmax, ymax); } void ParticleSystem::getLinearAcceleration(love::Vector &min, love::Vector &max) const { min = linearAccelerationMin; max = linearAccelerationMax; } void ParticleSystem::setRadialAcceleration(float acceleration) { radialAccelerationMin = radialAccelerationMax = acceleration; } void ParticleSystem::setRadialAcceleration(float min, float max) { radialAccelerationMin = min; radialAccelerationMax = max; } void ParticleSystem::getRadialAcceleration(float &min, float &max) const { min = radialAccelerationMin; max = radialAccelerationMax; } void ParticleSystem::setTangentialAcceleration(float acceleration) { tangentialAccelerationMin = tangentialAccelerationMax = acceleration; } void ParticleSystem::setTangentialAcceleration(float min, float max) { tangentialAccelerationMin = min; tangentialAccelerationMax = max; } void ParticleSystem::getTangentialAcceleration(float &min, float &max) const { min = tangentialAccelerationMin; max = tangentialAccelerationMax; } void ParticleSystem::setLinearDamping(float min, float max) { linearDampingMin = min; linearDampingMax = max; } void ParticleSystem::getLinearDamping(float &min, float &max) const { min = linearDampingMin; max = linearDampingMax; } void ParticleSystem::setSize(float size) { sizes.resize(1); sizes[0] = size; } void ParticleSystem::setSizes(const std::vector &newSizes) { sizes = newSizes; } const std::vector &ParticleSystem::getSizes() const { return sizes; } void ParticleSystem::setSizeVariation(float variation) { sizeVariation = variation; } float ParticleSystem::getSizeVariation() const { return sizeVariation; } void ParticleSystem::setRotation(float rotation) { rotationMin = rotationMax = rotation; } void ParticleSystem::setRotation(float min, float max) { rotationMin = min; rotationMax = max; } void ParticleSystem::getRotation(float &min, float &max) const { min = rotationMin; max = rotationMax; } void ParticleSystem::setSpin(float spin) { spinStart = spin; spinEnd = spin; } void ParticleSystem::setSpin(float start, float end) { spinStart = start; spinEnd = end; } void ParticleSystem::getSpin(float &start, float &end) const { start = spinStart; end = spinEnd; } void ParticleSystem::setSpinVariation(float variation) { spinVariation = variation; } float ParticleSystem::getSpinVariation() const { return spinVariation; } void ParticleSystem::setOffset(float x, float y) { offset = love::Vector(x, y); defaultOffset = false; } love::Vector ParticleSystem::getOffset() const { return offset; } void ParticleSystem::setColor(const std::vector &newColors) { colors = newColors; for (Colorf &c : colors) { // We want to store the colors as [0, 1], rather than [0, 255]. c.r /= 255.0f; c.g /= 255.0f; c.b /= 255.0f; c.a /= 255.0f; } } std::vector ParticleSystem::getColor() const { // The particle system stores colors in the range of [0, 1]... std::vector ncolors(colors); for (Colorf &c : ncolors) { c.r *= 255.0f; c.g *= 255.0f; c.b *= 255.0f; c.a *= 255.0f; } return ncolors; } void ParticleSystem::setQuads(const std::vector &newQuads) { std::vector> quadlist; quadlist.reserve(newQuads.size()); for (Quad *q : newQuads) quadlist.push_back(q); quads = quadlist; if (defaultOffset) resetOffset(); } void ParticleSystem::setQuads() { quads.clear(); } std::vector ParticleSystem::getQuads() const { std::vector quadlist; quadlist.reserve(quads.size()); for (const StrongRef &q : quads) quadlist.push_back(q.get()); return quadlist; } void ParticleSystem::setRelativeRotation(bool enable) { relativeRotation = enable; } bool ParticleSystem::hasRelativeRotation() const { return relativeRotation; } uint32 ParticleSystem::getCount() const { return activeParticles; } void ParticleSystem::start() { active = true; } void ParticleSystem::stop() { active = false; life = lifetime; emitCounter = 0; } void ParticleSystem::pause() { active = false; } void ParticleSystem::reset() { if (pMem == nullptr) return; pFree = pMem; pHead = nullptr; pTail = nullptr; activeParticles = 0; life = lifetime; emitCounter = 0; } void ParticleSystem::emit(uint32 num) { if (!active) return; num = std::min(num, maxParticles - activeParticles); while (num--) addParticle(1.0f); } bool ParticleSystem::isActive() const { return active; } bool ParticleSystem::isPaused() const { return !active && life < lifetime; } bool ParticleSystem::isStopped() const { return !active && life >= lifetime; } bool ParticleSystem::isEmpty() const { return activeParticles == 0; } bool ParticleSystem::isFull() const { return activeParticles == maxParticles; } void ParticleSystem::update(float dt) { if (pMem == nullptr || dt == 0.0f) return; // Traverse all particles and update. Particle *p = pHead; while (p) { // Decrease lifespan. p->life -= dt; if (p->life <= 0) p = removeParticle(p); else { // Temp variables. love::Vector radial, tangential; love::Vector ppos = p->position; // Get vector from particle center to particle. radial = ppos - p->origin; radial.normalize(); tangential = radial; // Resize radial acceleration. radial *= p->radialAcceleration; // Calculate tangential acceleration. { float a = tangential.getX(); tangential.setX(-tangential.getY()); tangential.setY(a); } // Resize tangential. tangential *= p->tangentialAcceleration; // Update velocity. p->velocity += (radial + tangential + p->linearAcceleration) * dt; // Apply damping. p->velocity *= 1.0f / (1.0f + p->linearDamping * dt); // Modify position. ppos += p->velocity * dt; p->position = ppos; const float t = 1.0f - p->life / p->lifetime; // Rotate. p->rotation += (p->spinStart * (1.0f - t) + p->spinEnd * t) * dt; p->angle = p->rotation; if (relativeRotation) p->angle += atan2f(p->velocity.y, p->velocity.x); // Change size according to given intervals: // i = 0 1 2 3 n-1 // |-------|-------|------|--- ... ---| // t = 0 1/(n-1) 3/(n-1) 1 // // `s' is the interpolation variable scaled to the current // interval width, e.g. if n = 5 and t = 0.3, then the current // indices are 1,2 and s = 0.3 - 0.25 = 0.05 float s = p->sizeOffset + t * p->sizeIntervalSize; // size variation s *= (float)(sizes.size() - 1); // 0 <= s < sizes.size() size_t i = (size_t)s; size_t k = (i == sizes.size() - 1) ? i : i + 1; // boundary check (prevents failing on t = 1.0f) s -= (float)i; // transpose s to be in interval [0:1]: i <= s < i + 1 ~> 0 <= s < 1 p->size = sizes[i] * (1.0f - s) + sizes[k] * s; // Update color according to given intervals (as above) s = t * (float)(colors.size() - 1); i = (size_t)s; k = (i == colors.size() - 1) ? i : i + 1; s -= (float)i; // 0 <= s <= 1 p->color = colors[i] * (1.0f - s) + colors[k] * s; // Update the quad index. k = quads.size(); if (k > 0) { s = t * (float) k; // [0:numquads-1] (clamped below) i = (s > 0.0f) ? (size_t) s : 0; p->quadIndex = (int) ((i < k) ? i : k - 1); } // Next particle. p = p->next; } } // Make some more particles. if (active) { float rate = 1.0f / emissionRate; // the amount of time between each particle emit emitCounter += dt; float total = emitCounter - rate; while (emitCounter > rate) { addParticle(1.0f - (emitCounter - rate) / total); emitCounter -= rate; } life -= dt; if (lifetime != -1 && life < 0) stop(); } prevPosition = position; } bool ParticleSystem::getConstant(const char *in, AreaSpreadDistribution &out) { return distributions.find(in, out); } bool ParticleSystem::getConstant(AreaSpreadDistribution in, const char *&out) { return distributions.find(in, out); } bool ParticleSystem::getConstant(const char *in, InsertMode &out) { return insertModes.find(in, out); } bool ParticleSystem::getConstant(InsertMode in, const char *&out) { return insertModes.find(in, out); } StringMap::Entry ParticleSystem::distributionsEntries[] = { { "none", DISTRIBUTION_NONE }, { "uniform", DISTRIBUTION_UNIFORM }, { "normal", DISTRIBUTION_NORMAL }, { "ellipse", DISTRIBUTION_ELLIPSE }, }; StringMap ParticleSystem::distributions(ParticleSystem::distributionsEntries, sizeof(ParticleSystem::distributionsEntries)); StringMap::Entry ParticleSystem::insertModesEntries[] = { { "top", INSERT_MODE_TOP }, { "bottom", INSERT_MODE_BOTTOM }, { "random", INSERT_MODE_RANDOM }, }; StringMap ParticleSystem::insertModes(ParticleSystem::insertModesEntries, sizeof(ParticleSystem::insertModesEntries)); } // graphics } // love