Why all particle example class in CCParticleExamples need texture ?

cocos2d-x C++
#1

//Error code
ARCH_OPTIMAL_PARTICLE_SYSTEM* particle = CCParticleMeteor::node();
// this is CCLayer object
this~~>addChild;
but when set a texture is Ok
//Good code
ARCH_OPTIMAL_PARTICLE_SYSTEM* particle = CCParticleMeteor::node;
particle~~>setTexture(CCTextureCache::sharedTextureCache()>addImage);
// this is CCLayer object
this>addChild(particle);

Why?
How I could run a particle example without set texture ?
Thanks!

#2

You need something to display on each point or quad.
Otherwise, you can hack the particle code, use ccDrawPoint instead of drawing texture in CCParticleSystemPoint.cpp