The Problem with Particles

So, last post I mentioned that I had finished off the particle emitter system in a prototype environment (literally a blank 2D canvas) but the next job was to take those particle emitters and drop them into the game environment. I had initially through that I would just overlay the particles over the top of the game scene and it wouldn’t be all that bad if you could see particles through walls; in-game walls aren’t taller than people anyway so it should be okay, surely.

But it wasn’t okay, it looked terrible.

In an “Isometric” scene, zSorting (the order things are rendered in so behind/in-front looks right) is done from the top of the screen to the bottom in linear order. In-engine at the moment, only 1 object (a wall tile, a person, a door) can be on 1 tile at a time, so the engine just renders whatever object is on whatever tile starting at the top of the screen down to the bottom. However, there can be 2000 particles on one tile, and incorporating them into the zSorting populator and renderer took some fairly heavy changes to the way it works.

Every particle has to remember what the y-axis of the tile was for the emitter that it came from and then gets inserted into a massive stack in order of y-axis, with up to 2000 other particles sharing the same y-axis. So there’s an array called ParticleSorter(200,2000), the first dimension is the y axis, and the second is the particular particle that’s on that axis. Once all the particles are added to that array stack, the stack is then read from during the zRenderer routine.

It’s not perfect yet; particles need to be given a concept of “floor” for them to land on, but the rendering is working and it seems to be fairly pretty so far. Here’s a video where you can see a fairly early implementation of breakable doors with particle effects.

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