text: /****************************************************************************
  Copyright (c) 2008-2010 Ricardo Quesada
  Copyright (c) 2009      Leonardo Kasperavičius
  Copyright (c) 2010-2012 cocos2d-x.org
  Copyright (c) 2011      Zynga Inc.
  Copyright (c) 2013-2014 Chukong Technologies Inc.
  
  http://www.cocos2d-x.org
   
  Permission is hereby granted, free of charge, to any person obtaining a copy
  of this software and associated documentation files (the "Software"), to deal
  in the Software without restriction, including without limitation the rights
  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  copies of the Software, and to permit persons to whom the Software is
  furnished to do so, subject to the following conditions:
  
  The above copyright notice and this permission notice shall be included in
  all copies or substantial portions of the Software.
  
  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  THE SOFTWARE.
  ****************************************************************************/
  
  #include "CCGL.h"
  #include "2d/CCParticleSystemQuad.h"
  #include "2d/CCSpriteFrame.h"
  #include "2d/CCDirector.h"
  #include "CCParticleBatchNode.h"
  #include "2d/CCTextureAtlas.h"
  #include "CCShaderCache.h"
  #include "2d/ccGLStateCache.h"
  #include "2d/CCGLProgram.h"
  #include "TransformUtils.h"
  #include "2d/CCEventType.h"
  #include "CCConfiguration.h"
  #include "2d/renderer/CCRenderer.h"
  #include "2d/renderer/CCQuadCommand.h"
  #include "2d/renderer/CCCustomCommand.h"
  
  // extern
  #include "2d/CCEventListenerCustom.h"
  #include "2d/CCEventDispatcher.h"
  
  NS_CC_BEGIN
  
  //implementation ParticleSystemQuad
  // overriding the init method
  bool ParticleSystemQuad::initWithTotalParticles(int numberOfParticles)
  {
      // base initialization
      if( ParticleSystem::initWithTotalParticles(numberOfParticles) ) 
      {
          // allocating data space
          if( ! this->allocMemory() ) {
              this->release();
              return false;
          }
  
          initIndices();
          if (Configuration::getInstance()->supportsShareableVAO())
          {
              setupVBOandVAO();
          }
          else
          {
              setupVBO();
          }
  
          setShaderProgram(ShaderCache::getInstance()->getProgram(GLProgram::SHADER_NAME_POSITION_TEXTURE_COLOR_NO_MVP));
          
  #if CC_ENABLE_CACHE_TEXTURE_DATA
          // Need to listen the event only when not use batchnode, because it will use VBO
          auto listener = EventListenerCustom::create(EVENT_COME_TO_FOREGROUND, CC_CALLBACK_1(ParticleSystemQuad::listenBackToForeground, this));
          _eventDispatcher->addEventListenerWithSceneGraphPriority(listener, this);
  #endif
  
          return true;
      }
      return false;
  }
  
  ParticleSystemQuad::ParticleSystemQuad()
  :_quads(nullptr)
  ,_indices(nullptr)
  ,_VAOname(0)
  {
      memset(_buffersVBO, 0, sizeof(_buffersVBO));
  }
  
  ParticleSystemQuad::~ParticleSystemQuad()
  {
      if (nullptr == _batchNode)
      {
          CC_SAFE_FREE(_quads);
          CC_SAFE_FREE(_indices);
          glDeleteBuffers(2, &_buffersVBO[0]);
          if (Configuration::getInstance()->supportsShareableVAO())
          {
              glDeleteVertexArrays(1, &_VAOname);
              GL::bindVAO(0);
          }
      }
  }
  
  // implementation ParticleSystemQuad
  
  ParticleSystemQuad * ParticleSystemQuad::create(const std::string& filename)
  {
      ParticleSystemQuad *ret = new ParticleSystemQuad();
      if (ret && ret->initWithFile(filename))
      {
          ret->autorelease();
          return ret;
      }
      CC_SAFE_DELETE(ret);
      return ret;
  }
  
  ParticleSystemQuad * ParticleSystemQuad::createWithTotalParticles(int numberOfParticles) {
      ParticleSystemQuad *ret = new ParticleSystemQuad();
      if (ret && ret->initWithTotalParticles(numberOfParticles))
      {
          ret->autorelease();
          return ret;
      }
      CC_SAFE_DELETE(ret);
      return ret;
  }
  
  
  // pointRect should be in Texture coordinates, not pixel coordinates
  void ParticleSystemQuad::initTexCoordsWithRect(const Rect& pointRect)
  {
      // convert to Tex coords
  
      Rect rect = Rect(
          pointRect.origin.x * CC_CONTENT_SCALE_FACTOR(),
          pointRect.origin.y * CC_CONTENT_SCALE_FACTOR(),
          pointRect.size.width * CC_CONTENT_SCALE_FACTOR(),
          pointRect.size.height * CC_CONTENT_SCALE_FACTOR());
  
      GLfloat wide = (GLfloat) pointRect.size.width;
      GLfloat high = (GLfloat) pointRect.size.height;
  
      if (_texture)
      {
          wide = (GLfloat)_texture->getPixelsWide();
          high = (GLfloat)_texture->getPixelsHigh();
      }
  
  #if CC_FIX_ARTIFACTS_BY_STRECHING_TEXEL
      GLfloat left = (rect.origin.x*2+1) / (wide*2);
      GLfloat bottom = (rect.origin.y*2+1) / (high*2);
      GLfloat right = left + (rect.size.width*2-2) / (wide*2);
      GLfloat top = bottom + (rect.size.height*2-2) / (high*2);
  #else
      GLfloat left = rect.origin.x / wide;
      GLfloat bottom = rect.origin.y / high;
      GLfloat right = left + rect.size.width / wide;
      GLfloat top = bottom + rect.size.height / high;
  #endif // ! CC_FIX_ARTIFACTS_BY_STRECHING_TEXEL
  
      // Important. Texture in cocos2d are inverted, so the Y component should be inverted
      CC_SWAP( top, bottom, float);
  
      V3F_C4B_T2F_Quad *quads = nullptr;
      unsigned int start = 0, end = 0;
      if (_batchNode)
      {
          quads = _batchNode->getTextureAtlas()->getQuads();
          start = _atlasIndex;
          end = _atlasIndex + _totalParticles;
      }
      else
      {
          quads = _quads;
          start = 0;
          end = _totalParticles;
      }
  
      for(unsigned int i=start; i<end; i++) 
      {
          // bottom-left vertex:
          quads[i].bl.texCoords.u = left;
          quads[i].bl.texCoords.v = bottom;
          // bottom-right vertex:
          quads[i].br.texCoords.u = right;
          quads[i].br.texCoords.v = bottom;
          // top-left vertex:
          quads[i].tl.texCoords.u = left;
          quads[i].tl.texCoords.v = top;
          // top-right vertex:
          quads[i].tr.texCoords.u = right;
          quads[i].tr.texCoords.v = top;
      }
  }
  
  void ParticleSystemQuad::updateTexCoords()
  {
      if (_texture)
      {
          const Size& s = _texture->getContentSize();
          initTexCoordsWithRect(Rect(0, 0, s.width, s.height));
      }
  }
  
  void ParticleSystemQuad::setTextureWithRect(Texture2D *texture, const Rect& rect)
  {
      // Only update the texture if is different from the current one
      if( !_texture || texture->getName() != _texture->getName() )
      {
          ParticleSystem::setTexture(texture);
      }
  
      this->initTexCoordsWithRect(rect);
  }
  
  void ParticleSystemQuad::setTexture(Texture2D* texture)
  {
      const Size& s = texture->getContentSize();
      this->setTextureWithRect(texture, Rect(0, 0, s.width, s.height));
  }
  
  void ParticleSystemQuad::setDisplayFrame(SpriteFrame *spriteFrame)
  {
      CCASSERT(spriteFrame->getOffsetInPixels().equals(Vector2::ZERO), 
               "QuadParticle only supports SpriteFrames with no offsets");
  
      // update texture before updating texture rect
      if ( !_texture || spriteFrame->getTexture()->getName() != _texture->getName())
      {
          this->setTexture(spriteFrame->getTexture());
      }
  }
  
  void ParticleSystemQuad::initIndices()
  {
      for(int i = 0; i < _totalParticles; ++i)
      {
          const unsigned int i6 = i*6;
          const unsigned int i4 = i*4;
          _indices[i6+0] = (GLushort) i4+0;
          _indices[i6+1] = (GLushort) i4+1;
          _indices[i6+2] = (GLushort) i4+2;
  
          _indices[i6+5] = (GLushort) i4+1;
          _indices[i6+4] = (GLushort) i4+2;
          _indices[i6+3] = (GLushort) i4+3;
      }
  }
  
  void ParticleSystemQuad::updateQuadWithParticle(tParticle* particle, const Vector2& newPosition)
  {
      V3F_C4B_T2F_Quad *quad;
  
      if (_batchNode)
      {
          V3F_C4B_T2F_Quad *batchQuads = _batchNode->getTextureAtlas()->getQuads();
          quad = &(batchQuads[_atlasIndex+particle->atlasIndex]);
      }
      else
      {
          quad = &(_quads[_particleIdx]);
      }
      Color4B color = (_opacityModifyRGB)
          ? Color4B( particle->color.r*particle->color.a*255, particle->color.g*particle->color.a*255, particle->color.b*particle->color.a*255, particle->color.a*255)
          : Color4B( particle->color.r*255, particle->color.g*255, particle->color.b*255, particle->color.a*255);
  
      quad->bl.colors = color;
      quad->br.colors = color;
      quad->tl.colors = color;
      quad->tr.colors = color;
  
      // vertices
      GLfloat size_2 = particle->size/2;
      if (particle->rotation) 
      {
          GLfloat x1 = -size_2;
          GLfloat y1 = -size_2;
  
          GLfloat x2 = size_2;
          GLfloat y2 = size_2;
          GLfloat x = newPosition.x;
          GLfloat y = newPosition.y;
  
          GLfloat r = (GLfloat)-CC_DEGREES_TO_RADIANS(particle->rotation);
          GLfloat cr = cosf(r);
          GLfloat sr = sinf(r);
          GLfloat ax = x1 * cr - y1 * sr + x;
          GLfloat ay = x1 * sr + y1 * cr + y;
          GLfloat bx = x2 * cr - y1 * sr + x;
          GLfloat by = x2 * sr + y1 * cr + y;
          GLfloat cx = x2 * cr - y2 * sr + x;
          GLfloat cy = x2 * sr + y2 * cr + y;
          GLfloat dx = x1 * cr - y2 * sr + x;
          GLfloat dy = x1 * sr + y2 * cr + y;
  
          // bottom-left
          quad->bl.vertices.x = ax;
          quad->bl.vertices.y = ay;
  
          // bottom-right vertex:
          quad->br.vertices.x = bx;
          quad->br.vertices.y = by;
  
          // top-left vertex:
          quad->tl.vertices.x = dx;
          quad->tl.vertices.y = dy;
  
          // top-right vertex:
          quad->tr.vertices.x = cx;
          quad->tr.vertices.y = cy;
      } 
      else 
      {
          // bottom-left vertex:
          quad->bl.vertices.x = newPosition.x - size_2;
          quad->bl.vertices.y = newPosition.y - size_2;
  
          // bottom-right vertex:
          quad->br.vertices.x = newPosition.x + size_2;
          quad->br.vertices.y = newPosition.y - size_2;
  
          // top-left vertex:
          quad->tl.vertices.x = newPosition.x - size_2;
          quad->tl.vertices.y = newPosition.y + size_2;
  
          // top-right vertex:
          quad->tr.vertices.x = newPosition.x + size_2;
          quad->tr.vertices.y = newPosition.y + size_2;                
      }
  }
  void ParticleSystemQuad::postStep()
  {
      glBindBuffer(GL_ARRAY_BUFFER, _buffersVBO[0]);
      
      // Option 1: Sub Data
      glBufferSubData(GL_ARRAY_BUFFER, 0, sizeof(_quads[0])*_totalParticles, _quads);
      
      // Option 2: Data
      //  glBufferData(GL_ARRAY_BUFFER, sizeof(quads_[0]) * particleCount, quads_, GL_DYNAMIC_DRAW);
      
      // Option 3: Orphaning + glMapBuffer
      // glBufferData(GL_ARRAY_BUFFER, sizeof(_quads[0])*_totalParticles, nullptr, GL_STREAM_DRAW);
      // void *buf = glMapBuffer(GL_ARRAY_BUFFER, GL_WRITE_ONLY);
      // memcpy(buf, _quads, sizeof(_quads[0])*_totalParticles);
      // glUnmapBuffer(GL_ARRAY_BUFFER);
      
      glBindBuffer(GL_ARRAY_BUFFER, 0);
      
      CHECK_GL_ERROR_DEBUG();
  }
  
  // overriding draw method
  void ParticleSystemQuad::draw(Renderer *renderer, const Matrix &transform, bool transformUpdated)
  {
      CCASSERT( _particleIdx == 0 || _particleIdx == _particleCount, "Abnormal error in particle quad");
      //quad command
      if(_particleIdx > 0)
      {
          _quadCommand.init(_globalZOrder, _texture->getName(), _shaderProgram, _blendFunc, _quads, _particleIdx, transform);
          renderer->addCommand(&_quadCommand);
      }
  }
  
  void ParticleSystemQuad::setTotalParticles(int tp)
  {
      // If we are setting the total number of particles to a number higher
      // than what is allocated, we need to allocate new arrays
      if( tp > _allocatedParticles )
      {
          // Allocate new memory
          size_t particlesSize = tp * sizeof(tParticle);
          size_t quadsSize = sizeof(_quads[0]) * tp * 1;
          size_t indicesSize = sizeof(_indices[0]) * tp * 6 * 1;
  
          tParticle* particlesNew = (tParticle*)realloc(_particles, particlesSize);
          V3F_C4B_T2F_Quad* quadsNew = (V3F_C4B_T2F_Quad*)realloc(_quads, quadsSize);
          GLushort* indicesNew = (GLushort*)realloc(_indices, indicesSize);
  
          if (particlesNew && quadsNew && indicesNew)
          {
              // Assign pointers
              _particles = particlesNew;
              _quads = quadsNew;
              _indices = indicesNew;
  
              // Clear the memory
              memset(_particles, 0, particlesSize);
              memset(_quads, 0, quadsSize);
              memset(_indices, 0, indicesSize);
              
              _allocatedParticles = tp;
          }
          else
          {
              // Out of memory, failed to resize some array
              if (particlesNew) _particles = particlesNew;
              if (quadsNew) _quads = quadsNew;
              if (indicesNew) _indices = indicesNew;
  
              CCLOG("Particle system: out of memory");
              return;
          }
  
          _totalParticles = tp;
  
          // Init particles
          if (_batchNode)
          {
              for (int i = 0; i < _totalParticles; i++)
              {
                  _particles[i].atlasIndex=i;
              }
          }
  
          initIndices();
          if (Configuration::getInstance()->supportsShareableVAO())
          {
              setupVBOandVAO();
          }
          else
          {
              setupVBO();
          }
          
          // fixed http://www.cocos2d-x.org/issues/3990
          // Updates texture coords.
          updateTexCoords();
      }
      else
      {
          _totalParticles = tp;
      }
      
      resetSystem();
  }
  
  void ParticleSystemQuad::setupVBOandVAO()
  {
      // clean VAO
      glDeleteBuffers(2, &_buffersVBO[0]);
      glDeleteVertexArrays(1, &_VAOname);
      GL::bindVAO(0);
      
      glGenVertexArrays(1, &_VAOname);
      GL::bindVAO(_VAOname);
  
  #define kQuadSize sizeof(_quads[0].bl)
  
      glGenBuffers(2, &_buffersVBO[0]);
  
      glBindBuffer(GL_ARRAY_BUFFER, _buffersVBO[0]);
      glBufferData(GL_ARRAY_BUFFER, sizeof(_quads[0]) * _totalParticles, _quads, GL_DYNAMIC_DRAW);
  
      // vertices
      glEnableVertexAttribArray(GLProgram::VERTEX_ATTRIB_POSITION);
      glVertexAttribPointer(GLProgram::VERTEX_ATTRIB_POSITION, 2, GL_FLOAT, GL_FALSE, kQuadSize, (GLvoid*) offsetof( V3F_C4B_T2F, vertices));
  
      // colors
      glEnableVertexAttribArray(GLProgram::VERTEX_ATTRIB_COLOR);
      glVertexAttribPointer(GLProgram::VERTEX_ATTRIB_COLOR, 4, GL_UNSIGNED_BYTE, GL_TRUE, kQuadSize, (GLvoid*) offsetof( V3F_C4B_T2F, colors));
  
      // tex coords
      glEnableVertexAttribArray(GLProgram::VERTEX_ATTRIB_TEX_COORDS);
      glVertexAttribPointer(GLProgram::VERTEX_ATTRIB_TEX_COORDS, 2, GL_FLOAT, GL_FALSE, kQuadSize, (GLvoid*) offsetof( V3F_C4B_T2F, texCoords));
  
      glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, _buffersVBO[1]);
      glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(_indices[0]) * _totalParticles * 6, _indices, GL_STATIC_DRAW);
  
      // Must unbind the VAO before changing the element buffer.
      GL::bindVAO(0);
      glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
      glBindBuffer(GL_ARRAY_BUFFER, 0);
  
      CHECK_GL_ERROR_DEBUG();
  }
  
  void ParticleSystemQuad::setupVBO()
  {
      glDeleteBuffers(2, &_buffersVBO[0]);
      
      glGenBuffers(2, &_buffersVBO[0]);
  
      glBindBuffer(GL_ARRAY_BUFFER, _buffersVBO[0]);
      glBufferData(GL_ARRAY_BUFFER, sizeof(_quads[0]) * _totalParticles, _quads, GL_DYNAMIC_DRAW);
      glBindBuffer(GL_ARRAY_BUFFER, 0);
  
      glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, _buffersVBO[1]);
      glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(_indices[0]) * _totalParticles * 6, _indices, GL_STATIC_DRAW);
      glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
  
      CHECK_GL_ERROR_DEBUG();
  }
  
  void ParticleSystemQuad::listenBackToForeground(EventCustom* event)
  {
      if (Configuration::getInstance()->supportsShareableVAO())
      {
          setupVBOandVAO();
      }
      else
      {
          setupVBO();
      }
  }
  
  bool ParticleSystemQuad::allocMemory()
  {
      CCASSERT( ( !_quads && !_indices), "Memory already alloced");
      CCASSERT( !_batchNode, "Memory should not be alloced when not using batchNode");
  
      CC_SAFE_FREE(_quads);
      CC_SAFE_FREE(_indices);
  
      _quads = (V3F_C4B_T2F_Quad*)malloc(_totalParticles * sizeof(V3F_C4B_T2F_Quad));
      _indices = (GLushort*)malloc(_totalParticles * 6 * sizeof(GLushort));
      
      if( !_quads || !_indices) 
      {
          CCLOG("cocos2d: Particle system: not enough memory");
          CC_SAFE_FREE(_quads);
          CC_SAFE_FREE(_indices);
  
          return false;
      }
  
      memset(_quads, 0, _totalParticles * sizeof(V3F_C4B_T2F_Quad));
      memset(_indices, 0, _totalParticles * 6 * sizeof(GLushort));
  
      return true;
  }
  
  void ParticleSystemQuad::setBatchNode(ParticleBatchNode * batchNode)
  {
      if( _batchNode != batchNode ) 
      {
          ParticleBatchNode* oldBatch = _batchNode;
  
          ParticleSystem::setBatchNode(batchNode);
  
          // NEW: is self render ?
          if( ! batchNode ) 
          {
              allocMemory();
              initIndices();
              setTexture(oldBatch->getTexture());
              if (Configuration::getInstance()->supportsShareableVAO())
              {
                  setupVBOandVAO();
              }
              else
              {
                  setupVBO();
              }
          }
          // OLD: was it self render ? cleanup
          else if( !oldBatch )
          {
              // copy current state to batch
              V3F_C4B_T2F_Quad *batchQuads = _batchNode->getTextureAtlas()->getQuads();
              V3F_C4B_T2F_Quad *quad = &(batchQuads[_atlasIndex] );
              memcpy( quad, _quads, _totalParticles * sizeof(_quads[0]) );
  
              CC_SAFE_FREE(_quads);
              CC_SAFE_FREE(_indices);
  
              glDeleteBuffers(2, &_buffersVBO[0]);
              memset(_buffersVBO, 0, sizeof(_buffersVBO));
              if (Configuration::getInstance()->supportsShareableVAO())
              {
                  glDeleteVertexArrays(1, &_VAOname);
                  GL::bindVAO(0);
                  _VAOname = 0;
              }
          }
      }
  }
  
  ParticleSystemQuad * ParticleSystemQuad::create() {
      ParticleSystemQuad *particleSystemQuad = new ParticleSystemQuad();
      if (particleSystemQuad && particleSystemQuad->init())
      {
          particleSystemQuad->autorelease();
          return particleSystemQuad;
      }
      CC_SAFE_DELETE(particleSystemQuad);
      return nullptr;
  }
  
  std::string ParticleSystemQuad::getDescription() const
  {
      return StringUtils::format("<ParticleSystemQuad | Tag = %d, Total Particles = %d>", _tag, _totalParticles);
  }
  
  NS_CC_END
  