Layers and Slowdown

[Shawn]

I do have a question about using the background system box however. If I have a large level, how is that going to work if I have a huge image? Wouldn't that cause a performance hit?

[Shawn]

Layers in themselves don't cause slowdown - I have an options frame with about twelve or so, as they're a useful way to separate out multiple dialogue boxes.

But their use combined with scrolling can cause a lot of slowdown because of the way that the collision masks work in MMF - the first layer has a complete collision mask calculated before the frame starts, and the ones above it are tested object-by-object. This means that if the majority of your gameplay happens on a layer higher than 1, it'll tend to be slower - often unnoticeably but sometimes a lot slower, if there are a lot of things going on.

Would be nice if we could specify which layer is the main game layer to calculate the collision mask. That way you could have layer 1 be the background scrolling and layer 2 the main game layer. That would solve the issue of layers and slowdown I would think. And would make for really easy parallax without cause for worry.

[RayMarble]

I guess the best thing to do is to put all the collisions, detectors etc on layer one and have all the actual graphics on layer 2 or above.

At least that's how I have it set up - with the addition of other layers: layer 2 for far background (sky, mountains), layer 3 for the player, NPC layer and all the worldly graphic, next layer is for the masks etc and another layer for the interface.