Hey, the entity i made isn't swimming when I place it in water, it just drops inside

 

The issue to this is here

I've been looking at the wolf AI but it still doesn't explain why the custom entity I made isn't swimming

Is your entity less than 2 blocks tall?

No, its 1.5

Hum. Then I don't know.

I had a similar swimming problem, but it was for a mob that was ~1 block tall.

The strange thing about it is that horses are 1.6 tall and can still swim.

You can try this:

 

@Override
public boolean handleWaterMovement()
    {
	this.boundingBox.minY += 0.4D;
        if (this.worldObj.handleMaterialAcceleration(this.boundingBox.expand(0.0D, 0.4D, 0.0D).contract(0.001D, 0.001D, 0.001D), Material.water, this)) {
            if (!this.inWater) {
                float f = MathHelper.sqrt_double(this.motionX * this.motionX * 0.20000000298023224D + this.motionY * this.motionY + this.motionZ * this.motionZ * 0.20000000298023224D) * 0.2F;

                if (f > 1.0F) {
                    f = 1.0F;
                }

                this.playSound(this.getSplashSound(), f, 1.0F + (this.rand.nextFloat() - this.rand.nextFloat()) * 0.4F);
                float f1 = (float)MathHelper.floor_double(this.boundingBox.minY);
                int i;
                float f2;
                float f3;

                for (i = 0; (float)i < 1.0F + this.width * 20.0F; ++i) {
                    f2 = (this.rand.nextFloat() * 2.0F - 1.0F) * this.width;
                    f3 = (this.rand.nextFloat() * 2.0F - 1.0F) * this.width;
                    this.worldObj.spawnParticle("bubble", this.posX + (double)f2, (double)(f1 + 1.0F), this.posZ + (double)f3, this.motionX, this.motionY - (double)(this.rand.nextFloat() * 0.2F), this.motionZ);
                }

                for (i = 0; (float)i < 1.0F + this.width * 20.0F; ++i) {
                    f2 = (this.rand.nextFloat() * 2.0F - 1.0F) * this.width;
                    f3 = (this.rand.nextFloat() * 2.0F - 1.0F) * this.width;
                    this.worldObj.spawnParticle("splash", this.posX + (double)f2, (double)(f1 + 1.0F), this.posZ + (double)f3, this.motionX, this.motionY, this.motionZ);
                }
            }

            this.fallDistance = 0.0F;
            this.inWater = true;
            this.extinguish();
        }
        else {
            this.inWater = false;
        }
	this.boundingBox.minY -= 0.4D;

        return this.inWater;
    }

 

(May need tweaks for your entity's size)

What do I do with the bounding box variables? In 1.9 and 1.8 it can't get the variables since they are finals

The modifications are just there to figure out if the entity is underwater.  The +0.4/-0.4 was to fake my entity being taller than it was.

I did this

	@Override
public boolean handleWaterMovement()
{
	if (this.worldObj.handleMaterialAcceleration(this.getEntityBoundingBox().expand(0.0D, 0.4D, 0.0D).contract(0.001D), Material.WATER, this)) {
		if (!this.inWater) {
			float f = MathHelper.sqrt_double(this.motionX * this.motionX * 0.20000000298023224D + this.motionY * this.motionY + this.motionZ * this.motionZ * 0.20000000298023224D) * 0.2F;

			if (f > 1.0F) {
				f = 1.0F;
			}

			this.playSound(this.getSplashSound(), f, 1.0F + (this.rand.nextFloat() - this.rand.nextFloat()) * 0.4F);
			float f1 = (float) MathHelper.floor_double(this.getEntityBoundingBox().minY);
			int i;
			float f2;
			float f3;

			for (i = 0; (float)i < 1.0F + this.width * 20.0F; ++i) {
				f2 = (this.rand.nextFloat() * 2.0F - 1.0F) * this.width;
				f3 = (this.rand.nextFloat() * 2.0F - 1.0F) * this.width;
				this.worldObj.spawnParticle(EnumParticleTypes.WATER_BUBBLE, this.posX + (double)f2, (double)(f1 + 1.0F), this.posZ + (double)f3, this.motionX, this.motionY - (double)(this.rand.nextFloat() * 0.2F), this.motionZ);
			}

			for (i = 0; (float)i < 1.0F + this.width * 20.0F; ++i) {
				f2 = (this.rand.nextFloat() * 2.0F - 1.0F) * this.width;
				f3 = (this.rand.nextFloat() * 2.0F - 1.0F) * this.width;
				this.worldObj.spawnParticle(EnumParticleTypes.WATER_SPLASH, this.posX + (double)f2, (double)(f1 + 1.0F), this.posZ + (double)f3, this.motionX, this.motionY, this.motionZ);
			}
		}

		this.fallDistance = 0.0F;
		this.inWater = true;
		this.extinguish();
	}
	else {
		this.inWater = false;
	}

	return this.inWater;
}

 

But it still doesn't swim

I am at a loss, then.

I notice the same thing in 1.8.. I have absolutely no clue why the swimming AI is malfunctioning

I just finished recreating the project and it STILL doesn't swim.

Ok.. Im at an absolute lost with this. Am I the only one expericing this bug?

Ok! I finally made some kind of progress on figuring out why the entity isn't jumping, I changed the class that the entity is extending into to

EntityModTameable

instead of

EntityModRideableTameable

and it begins swimming!! It has to be something inside

EntityModRideableTameable

that is messing around with the swimming AI.