VertexArray

[dydya-stepa]

What I found with VertexArray is that it's static so to speak. For my particle system I had to create my own vertex array implementation which reuses already allocated memory for vertex array. So I don't have to allocate it every frame. Is that intended behavior of VertexArray? Which makes it not very useful. As e.g. I might suspect tile engine probably would require also some sort of dynamic allocation. Which probably not that performance bad as with particles.

[Laurent]

For my particle system I had to create my own vertex array implementation which reuses already allocated memory for vertex array. So I don't have to allocate it every frame.

What was wrong with sf::VertexArray? You can allocate the vertices once (with the constructor or resize function) and then overwrite them every frame without touching the allocated memory.

And don't forget that sf::VertexArray is just provided for convenience, it's nothing more that a std::vector<sf::Vertex>. Use your own container if it doesn't fit your needs (that's why I always use the generic words "vertex array", not "sf::VertexArray").

[dydya-stepa]

The number of particles goes back and forth so when number decreases I don't remove the particles from array. So I have always maximum amount in array but track the number of used. And I'm using sf::Vertex.

[gyscos]

A VertexArray is a vector of vertex, meaning you can easily add and remove elements from its back.

You can also remove a vertex from anywhere in the array. To make it a little less slow, since order doesn't matter, you can swap it with the last element from the array, then pop the last element.