package org.loon.framework.android.game.action.sprite.effect;



import org.loon.framework.android.game.core.LSystem;

import org.loon.framework.android.game.core.graphics.opengl.GLEx;

import org.loon.framework.android.game.core.graphics.opengl.LTexture;



/**

 * Copyright 2008 - 2009

 * 

 * 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.

 * 

 * @project loonframework

 * @author chenpeng

 * @email??šceponline@yahoo.com.cn

 * @version 0.1

 */

public class SnowKernel implements IKernel {



	private boolean exist;



	private LTexture snow;



	private double offsetX, offsetY, speed, x, y, width, height, snowWidth,

			snowHeight;



	public SnowKernel(int n, int w, int h) {

		snow = new LTexture((LSystem.FRAMEWORK_IMG_NAME + "snow_" + n + ".png")

				.intern());

		snowWidth = snow.getWidth();

		snowHeight = snow.getHeight();

		width = w;

		height = h;

		offsetX = 0;

		offsetY = n * 0.6 + 1.9 + Math.random() * 0.2;

		speed = Math.random();

	}



	public void make() {

		exist = true;

		x = Math.random() * width;

		y = -snowHeight;

	}



	public void move() {

		if (!exist) {

			if (Math.random() < 0.002) {

				make();

			}

		} else {

			x += offsetX;

			y += offsetY;

			offsetX += speed;

			speed += (Math.random() - 0.5) * 0.3;

			if (offsetX >= 1.5) {

				offsetX = 1.5;

			}

			if (offsetX <= -1.5) {

				offsetX = -1.5;

			}

			if (speed >= 0.2) {

				speed = 0.2;

			}

			if (speed <= -0.2) {

				speed = -0.2;

			}

			if (y >= height) {

				y = -snowHeight;

				x = Math.random() * width;

			}

		}

	}



	public void draw(GLEx g) {

		if (exist) {

			g.drawTexture(snow, (int) x, (int) y);

		}

	}



	public LTexture getSnow() {

		return snow;

	}



	public double getSnowHeight() {

		return snowHeight;

	}



	public double getSnowWidth() {

		return snowWidth;

	}



}