Alright, so I've create a custom liquid.  All is fine and dandy except for a few things:

 

Material.water has a lot of side effects, as does Material.lava.  None of these side effects are controllable and I want to not-have some of them and have others.

 

Using water means that entities can swim "up" in it (and I'd like my custom 'liquid' to be a gas and not have that property).  It also causes the player to drown (and I do want that) and any material other than water resets the air meter.  For lava, this sets the player on fire and I don't want that.

 

Not using Material.water (or lava) and still letting vanilla code handling (render id 4) rendering causes it to crash, due to getFlowDirection being a static method inf BlockLiquid that checks for only water and lava materials.  Not using Material.water and letting the Forge renderer take over causes there to not be a "you are underwater" overlay and turn fog on, likely because it's handled by vanilla.

 

Anyone have solutions to this problem?  Registering an ISBRH and doing the rendering myself is fine, but I'd still like to cause the drowning effect.

For rendering, I'd use the forge fluid system. Idk about vanilla drowning, but since it's a gas it might be best to have your own "drowning" effect (without bubbles).

By taking a look at the code, couldn't you handle drowning by using an event handler using entityLivingEvent(Forgot name, not sure if it)?  Then create your own MaterialLiquid?

For rendering, I'd use the forge fluid system. Idk about vanilla drowning, but since it's a gas it might be best to have your own "drowning" effect (without bubbles).

 

Has its own problem, of not showing the "you are underwater" overlay.

 

Also, apparently the forge renderer doesn't render backfaces.  WTF.

 

By taking a look at the code, couldn't you handle drowning by using an event handler using entityLivingEvent(Forgot name, not sure if it)?  Then create your own MaterialLiquid?

 

Nope, because of how air is handled.

 

if (this.isEntityAlive() && this.isInsideOfMaterial(Material.water))
        {
            if (!this.canBreatheUnderwater() && !this.isPotionActive(Potion.waterBreathing.id) && !flag)
            {
                this.setAir(this.decreaseAirSupply(this.getAir()));
                //snipped
             }
        }
        else
        {
            this.setAir(300);
        }

I don't think the drowning effect is possible unless you can cause the check for block.getMaterial at isInsideOfMaterial in Entity to return true.  The alternative is program a "drowning" effect.  I think Galaticraft has a "drowning" effect in space, best to check, https://github.com/micdoodle8/Galacticraft.  If I find anything in there for you, I'll just edit this post.

 

EDIT: One thing that may peak your interest is https://github.com/micdoodle8/Galacticraft/blob/master/src/main/java/micdoodle8/mods/galacticraft/core/event/EventHandlerGC.java at the entityLivingEvent.

I'll dig around in there.