Event for Riding Entities Underwater

[GhostWolf2398]

Hello, I am GhostWolf, one of the coding developers for the Pixelmon mod (essentially Pokemon in Minecraft).

 

We were wondering if it would be possible to add an event into entityLivingBase that would allow us to specify custom behavior for when a player rides an entity underwater. We currently have several mounts that are capable of surfing and diving, and with the code in entityLivingBase lines 281-309 (and 305-309 in particular), as soon as a player goes fully underwater they unmount (whether it is just the natural up and down swimming on the mount or actually diving). Ideally we would be able to just override this or change the event response to this so that the player can remain on the mount.

 

Any help and suggestions you can give on this would be greatly appreciated. We would also be more than happy to take care of the needed coding if you had the way this should be done figured out.

 

 

 

        if (this.isEntityAlive() && this.isInsideOfMaterial(Material.water))

        {

            if (!this.canBreatheUnderwater() && !this.isPotionActive(Potion.waterBreathing.id) && !flag)

            {

                this.setAir(this.decreaseAirSupply(this.getAir()));

 

                if (this.getAir() == -20)

                {

                    this.setAir(0);

 

                    for (int i = 0; i < 8; ++i)

                    {

                        float f = this.rand.nextFloat() - this.rand.nextFloat();

                        float f1 = this.rand.nextFloat() - this.rand.nextFloat();

                        float f2 = this.rand.nextFloat() - this.rand.nextFloat();

                        this.worldObj.spawnParticle("bubble", this.posX + (double)f, this.posY + (double)f1, this.posZ + (double)f2, this.motionX, this.motionY, this.motionZ);

                    }

 

                    this.attackEntityFrom(DamageSource.drown, 2.0F);

                }

            }

 

            this.extinguish();

 

            if (!this.worldObj.isRemote && this.isRiding() && this.ridingEntity instanceof EntityLivingBase)

            {

                this.mountEntity((Entity)null);

            }

        }

 

[LexManos]

Could easily add a boolean Entity.shouldDismountWhenUnderwater(), Should be a Simple PR for someone to make. {I iz busy till the end of next week}

[GhostWolf2398]

I went ahead and wrote in the needed code. I can't get the patches to update or commit correctly to github, so here is the code for someone who can do that, all written out for you (red text is added, the rest is just to help you locate where to put it).

 

/** Number of ticks since last jump */

    private int jumpTicks;

    private float field_110151_bq;

   

    /** Determines if entity stays on mount when submerged in water. */

    public boolean stayMountedUnderWater = false;

 

    public EntityLivingBase(World par1World)

    {

 

and

 

                    this.attackEntityFrom(DamageSource.drown, 2.0F);

                }

            }

 

            this.extinguish();

 

            if (!this.worldObj.isRemote && this.isRiding() && this.ridingEntity instanceof EntityLivingBase)

            {

            if (!stayMountedUnderWater){

            this.mountEntity((Entity)null);

            }

            }

        }

 

[LexManos]

I was more thinking of a function in the mounted entity.

 

[GhostWolf2398]

This is the location in the code that causes the issue with underwater riding. Based on your comment, I looked at putting something inside the mountEntity() function, but that is only called when you change from mounting to unmounting, and that boolean variable if used there could cause other behavioral issues (such as never letting you get off the mount, etc)

 

The line I placed the check at is the only point at which you would want to circumvent the normal unmounting code for this kind of problem, as it is the only point where the unmounting is caused by the rider being located in water. By locating that boolean check there, you only get the bypass behavior under that one condition, and riding should behave entirely normally for all other situations.

 

If you meant a function in the code of the entity being mounted, it likely wouldn't solve the issue we are having, as it is this particular point in the code where it forces the unmounting, and any other function in the mounted entity that would say force re-mounting would be run too frequently while under water to be an elegant solution to the issue.

 

Hopefully that makes sense, feel free to correct me if I am wrong.

[LexManos]

            if (!this.worldObj.isRemote && this.isRiding() && this.ridingEntity instanceof EntityLivingBase)
            {
                  this.mountEntity((Entity)null);
            }

To:

            if (!this.worldObj.isRemote && this.isRiding() && ridingEntity != null && ridingEntity.shouldDismountInWater(this))
            {
                this.mountEntity((Entity)null);
            }

 

and in entity you have:

public boolean shouldDismountInWater(Entity rider)
{
    return this instanceof EntityLivingBase;
}

...

How is that confusing? Give the mounted the choice of kicking the mountee off if it so chooses, Which mimics what this is doing.

[GhostWolf2398]

That makes a lot of sense.

 

I was thinking you were suggesting only making the dismounting code inside the mount's code, and not doing the check at that line in the entityLivingBase code, since that wouldn't change things.

 

With the way you have it, it would give the ridden entity the control over kicking, which makes it more generally customizable, and it will make the check at the right place in code, so that is the best solution to the issue. Thanks for your help and insight.

[MrMasochism]

I've done the pull request for this:

 

https://github.com/MinecraftForge/MinecraftForge/pull/702