Scale.java

/**
 * Copyright 2008 - 2015 The Loon Game Engine Authors
 * 
 * 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 loon
 * @author cping
 * @email：javachenpeng@yahoo.com
 * @version 0.5
 */
package loon.utils;

public class Scale {

	public static class ScaledResource {

		public final Scale scale;

		public final String path;

		public ScaledResource(Scale scale, String path) {
			this.scale = scale;
			this.path = path;
		}

		@Override
		public String toString() {
			return scale + ": " + path;
		}
	}

	public static final Scale ONE = new Scale(1);

	public final float factor;

	public Scale(float factor) {
		this.factor = factor;
	}

	public float scaled(float length) {
		return factor * length;
	}

	public int scaledCeil(float length) {
		return MathUtils.iceil(scaled(length));
	}

	public int scaledFloor(float length) {
		return MathUtils.ifloor(scaled(length));
	}

	public float invScaled(float length) {
		return length / factor;
	}

	public int invScaledFloor(float length) {
		return MathUtils.ifloor(invScaled(length));
	}

	public int invScaledCeil(float length) {
		return MathUtils.iceil(invScaled(length));
	}

	public TArray<ScaledResource> getScaledResources(String path) {
		TArray<ScaledResource> rsrcs = new TArray<ScaledResource>();
		rsrcs.add(new ScaledResource(this, computePath(path, factor)));
		for (float rscale = MathUtils.ifloor(factor); rscale > 1; rscale -= 1) {
			if (rscale != factor)
				rsrcs.add(new ScaledResource(new Scale(rscale), computePath(
						path, rscale)));
		}
		rsrcs.add(new ScaledResource(ONE, path));
		return rsrcs;
	}

	private String computePath(String path, float scale) {
		if (scale <= 1f) {
			return path;
		}
		int scaleFactor = (int) (scale * 10);
		if (scaleFactor % 10 == 0) {
			scaleFactor /= 10;
		}
		int didx = path.lastIndexOf(".");
		if (didx == -1) {
			return path;
		} else {
			return path.substring(0, didx) + "@" + scaleFactor + "x"
					+ path.substring(didx);
		}
	}

	@Override
	public String toString() {
		return "x" + factor;
	}
}