apply( accuIndex ) {

		const stride = this.valueSize,
			buffer = this.buffer,
			offset = accuIndex * stride + stride,

			weight = this.cumulativeWeight,
			weightAdditive = this.cumulativeWeightAdditive,

			binding = this.binding;

		this.cumulativeWeight = 0;
		this.cumulativeWeightAdditive = 0;

		if ( weight < 1 ) {

			// accuN := accuN + original * ( 1 - cumulativeWeight )

			const originalValueOffset = stride * this._origIndex;

			this._mixBufferRegion(
				buffer, offset, originalValueOffset, 1 - weight, stride );

		}

		if ( weightAdditive > 0 ) {

			// accuN := accuN + additive accuN

			this._mixBufferRegionAdditive( buffer, offset, this._addIndex * stride, 1, stride );

		}

		for ( let i = stride, e = stride + stride; i !== e; ++ i ) {

			if ( buffer[ i ] !== buffer[ i + stride ] ) {

				// value has changed -> update scene graph

				binding.setValue( buffer, offset );
				break;

			}

		}

	}
Applies the state of `accu<i>` to the binding when accus differ.

@param {number} accuIndex - The accumulation index.