processSampler( map ) {

		const json = this.json;

		if ( ! json.samplers ) json.samplers = [];

		const samplerDef = {
			magFilter: THREE_TO_WEBGL[ map.magFilter ],
			minFilter: THREE_TO_WEBGL[ map.minFilter ],
			wrapS: THREE_TO_WEBGL[ map.wrapS ],
			wrapT: THREE_TO_WEBGL[ map.wrapT ]
		};

		return json.samplers.push( samplerDef ) - 1;

	}
Process sampler
@param {Texture} map Texture to process
@return {number}      Index of the processed texture in the "samplers" array