Zoom.java

/*******************************************************************************
 * Copyright 2012 bmanuel
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 ******************************************************************************/

package com.bitfire.postprocessing.filters;

import com.bitfire.utils.ShaderLoader;

public final class Zoom extends Filter<Zoom> {
	private float x, y, zoom;

	public enum Param implements Parameter {
		// @formatter:off
		Texture("u_texture0", 0), OffsetX("offset_x", 0), OffsetY("offset_y", 0), Zoom("zoom", 0), ;
		// @formatter:on

		private String mnemonic;
		private int elementSize;

		private Param (String mnemonic, int arrayElementSize) {
			this.mnemonic = mnemonic;
			this.elementSize = arrayElementSize;
		}

		@Override
		public String mnemonic () {
			return this.mnemonic;
		}

		@Override
		public int arrayElementSize () {
			return this.elementSize;
		}
	}

	public Zoom () {
		super(ShaderLoader.fromFile("zoom", "zoom"));
		rebind();
		setOrigin(0.5f, 0.5f);
		setZoom(1f);
	}

	/** Specify the zoom origin, in normalized screen coordinates. */
	public void setOrigin (float x, float y) {
		this.x = x;
		this.y = y;
		setParams(Param.OffsetX, this.x);
		setParams(Param.OffsetY, this.y);
		endParams();
	}

	public void setZoom (float zoom) {
		this.zoom = zoom;
		setParam(Param.Zoom, this.zoom);
	}

	public float getZoom () {
		return zoom;
	}

	public float getOriginX () {
		return x;
	}

	public float getOriginY () {
		return y;
	}

	@Override
	public void rebind () {
		// reimplement super to batch every parameter
		setParams(Param.Texture, u_texture0);
		setParams(Param.OffsetX, x);
		setParams(Param.OffsetY, y);
		setParams(Param.Zoom, zoom);
		endParams();
	}

	@Override
	protected void onBeforeRender () {
		inputTexture.bind(u_texture0);
	}
}