I've never heard this term [overdraw previewer] before, so can you explain it?
TL;DRThe overdraw previewer is a toggleable heat map showing how stacked, transparent particles hurt performance, so artists can spot hidden wasted effects and dial back; a graphics programmer's side project that the VFX team now maintains.
Basically, with particles there's a high transparency cost to them, because there's opacity or there's lack of opacity, and that incurs a cost. That's the transparency cost, but there's also the overdraw aspect of it, and Leo will explain it in a more concise way, but for me it's basically: we can quickly blow the budget, we can really hit the frames per second with our transparency costs if we get too carried away with adding particle after particle. So it's how they all stack up over each other. And the overdraw preview basically just shows a heat map. It's a toggle and it just draws the screen as a heat map. And it's got a guide showing you basically if it gets to this color, it's too high, so the overdraw cost is too high. You're wasting particles that can't be seen because there's something else in front of it. It's great. You just toggle it on and off. You can see, 'Oh, wow, great. I can't really see many effects on the screen right now. There's maybe some subtle dust scrolling,' but you stick it into the overdraw preview mode and it's fully white, and that's just too expensive and we need to dial that back.
So it's a great way to see things hidden behind other things that don't need to be there because you can't see it from that perspective.
Exactly. And like Leo says, the great skill that Leo and his guys have got is that they make our lives easier. They do as many things as they can to make our job easier, to help us stay within the limits of, again, the budget.
We try to. But for the overdraw visualizer, shout out to Alejandro. He's one of the graphics programmers; he did a side project and he basically gave it to us. We've taken it over and we'll maintain it. This is a nice collaboration again with the graphics guys.
Well, there's a massive crossover with graphics and VFX programming anyway. Don't want to sound too cheesy, but it's almost like the same family, isn't it? And you're a niche part of that department. So shout out to them.