Seteffect modes
 

Was talking to Holysheepy about this earlier... anyways.
seteffect seems to only have one mode, and it seems like a subtraction kind of thing. I suggest, like setimgeffect, seteffect be able to have its modes changed.

seteffectmode(2);

Would be very easy to implement I assume. I don't see why not.

You can also display a polygon-rectangle with any mode you want to use, seteffect() is basicly doing that.

Ya, but there are problems arising when using that method. Poly's aren't made to take into consideration light effects like seteffect is. Holysheepy posted about the problem he had, which was he needed light effects to be shown over the polygon, but tree's to be shown under the poly as well as over the player. It was a mess because he was using poly's instead of seteffect.

Lights don't show over the seteffect() last time I checked.

Hmmm should be layer 2, with a high y
Internally there is a layer between 2 and 3, but i cannot be used by script

I think you should be increasing the number of layers and adding support for drawing tiles above the player, it would be a much loved feature.

Ya, I'd love to be able to edit the layer of a layer :D
Also, lights can be drawn over set effect, if they're drawnaslight() or set on layer 3. That's why it's hard to do a seteffect thing with showpoly because it'd have to be on layer 3, but so would the light effects.

I think more layers should be added. If you dont want everyone to rewrite their scripts, you could just add negative layers, and (mabye) set the player default somewhere in the middle. (Example: layers from -50 til 4 (and above 4 of course). 4 and above are screen orientated, the others tile orientated. Player would be set to -25 or maybe lower, so you can easily place a lot of things under and above the player.)
Wouldnt fix the poly-lighteffect thing, but it would be a neat addition for sure.

Maybe just add decimal values into layers?
...1.9 - 2 - 2.1 - 2.2 - 2.3 - 2.4 - 2.5 - 2.6 - 2.7 - 2.8 - 2.9 - 3 - 3.1 - 3.2...
And so on.

I really dislike decimal values for layers. I like the layer functions of Game Maker. It goes from -10k til 10k if I remember right. Something like that would be neat, but I'm fine with around 20 til 30 layers ;o

Well, it's different when you've already have a game coded using layers to just throw in more layers. Decimals isn't practical, but in this sense it's flexible. Adding decimal values eliminates the need to take into consideration so much is already scripted to work with 3 layers because all you're doing is adding layers between the 3 layers, no before or after.