Water reflection - Layer problems

ID:139580
 
Nov 11 2010, 11:25 am
Code:
mob
    Login()
        ..()
        var/icon/I = icon(icon,icon_state)
        I.Flip(SOUTH)
        var/image/i = image(I,src,layer=TURF_LAYER-2)
        i.pixel_y -= 30
        underlays += i
turf
    city
        icon = 'humancity.dmi'
        floor
            icon_state = "1"
        water
            icon_state = "w"
            layer=TURF_LAYER-3
            New()
                icon_state = "wu"
                overlays += image('humancity.dmi',src,"water",layer=TURF_LAYER-1)


Problem description:
What I'm attempting to do here is to have a water reflection of the player's image.
The idea is simple: I give the player an underlay whose layer is TURF_LAYER-2.
The floor which the water is on is TURF_LAYER-3, and the transparent overlay of the water is TURF_LAYER-1, thus giving me:

LAYER(0) = (NULL)
LAYER(-1) = Transparent Overlay
LAYER(-2) = Reflection
LAYER(-3) = Floor

The problem is, however, when I run he code, the mob's underlay (the reflection) is actually on top of all of the turf, including /turf/city/floor , whose layer is TURF_LAYER.

I've tried changing the layers (tried to change values, and then layer type, etc.), but I didn't get any good results.

Any ideas as to why this is happening?

Thanks!
Nov 11 2010, 12:01 pm
You're doing it backwards. A better way would be to make the water transparent, and have it overtop a semi-transparent image of the player.
Nov 11 2010, 1:56 pm
layer -1 is FLOAT_LAYER, which is a special layer which means "always above whatever I'm overlayed on". Since TURF_LAYER is 2, TURF_LAYER-3 is -1 and things break. The solution is to use fractional values for the layer. So, TURF_LAYER - 0.75, 0.5, 0.25, etc. (multiples of 0.5, 0.25, 0.125, etc. are preferred).
Nov 11 2010, 4:32 pm
In response to Garthor
Garthor wrote:
layer -1 is FLOAT_LAYER, which is a special layer which means "always above whatever I'm overlayed on". Since TURF_LAYER is 2, TURF_LAYER-3 is -1 and things break. The solution is to use fractional values for the layer. So, TURF_LAYER - 0.75, 0.5, 0.25, etc. (multiples of 0.5, 0.25, 0.125, etc. are preferred).

Thanks a lot! Your solution worked beautifully.

Just to make sure, then:
1 (AREA_LAYER)
2 (TURF_LAYER)
3 (OBJ_LAYER)
4 (MOB_LAYER)


AREA_LAYER+1 = TURF_LAYER
TURF_LAYER+1 = OBJ_LAYER

Is that how layers actually work?
Nov 11 2010, 4:33 pm
In response to Popisfizzy
How and why would it be better to do this your way?
As in, is it better at CPU usage, memory handling... ?

Nov 13 2010, 4:25 am
In response to Gooseheaded
Gooseheaded wrote:
Just to make sure, then:
1 (AREA_LAYER)
2 (TURF_LAYER)
3 (OBJ_LAYER)
4 (MOB_LAYER)


AREA_LAYER+1 = TURF_LAYER
TURF_LAYER+1 = OBJ_LAYER

Is that how layers actually work?

Yes. Things like AREA_LAYER and TURF_LAYER, as well as others like TRUE and FALSE are simply text-substituted constants, no different than if you had done the following:
#define AREA_LAYER 1
#define TURF_LAYER 2
#define OBJ_LAYER 3
#define MOB_LAYER 4

#define TRUE 1
#define FALSE 0

So when you press compile, all instances of AREA_LAYER or TRUE are immediately text-swapped as if you had simply typed "1" instead. You can test this for yourself:
mob/verb/orly()
   usr << AREA_LAYER
   usr << isnum(AREA_LAYER)


This also applies to directions as well: NORTH, SOUTH, EAST, WEST, ...