RenderStyle.java

/*
 * Copyright 2010, 2011, 2012 mapsforge.org
 * Copyright 2013 Hannes Janetzek
 *
 * This file is part of the OpenScienceMap project (http://www.opensciencemap.org).
 *
 * This program is free software: you can redistribute it and/or modify it under the
 * terms of the GNU Lesser General Public License as published by the Free Software
 * Foundation, either version 3 of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY
 * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A
 * PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License along with
 * this program. If not, see <http://www.gnu.org/licenses/>.
 */
package org.oscim.theme.styles;

import static org.oscim.backend.canvas.Color.parseColor;

/**
 * A RenderInstruction is a basic graphical primitive to draw a map.
 */
public abstract class RenderStyle {

	public static abstract class StyleBuilder<T extends StyleBuilder<T>> {

		public String style;

		public int level;

		public int fillColor;

		public int strokeColor;
		public float strokeWidth;

		public T setStyle(String style) {
			this.style = style;
			return self();
		}

		public T level(int level) {
			this.level = level;
			return self();
		}

		public T outline(int color, float width) {
			this.strokeColor = color;
			this.strokeWidth = width;
			return self();
		}

		public T strokeColor(int color) {
			this.strokeColor = color;
			return self();
		}

		public T strokeColor(String color) {
			this.strokeColor = parseColor(color);
			return self();
		}

		public T strokeWidth(float width) {
			this.strokeWidth = width;
			return self();
		}

		public T color(int color) {
			this.fillColor = color;
			return self();
		}

		public T color(String color) {
			this.fillColor = parseColor(color);
			return self();
		}

		@SuppressWarnings("unchecked")
		protected T self() {
			return (T) this;
		}

		public abstract RenderStyle build();
	}

	/**
	 * Callback methods for rendering areas, ways and points of interest (POIs).
	 */
	public static interface Callback {
		/**
		 * Renders an area with the given parameters.
		 * 
		 * @param area
		 * @param level
		 */
		void renderArea(AreaStyle area, int level);

		/**
		 * Renders an extrusion with the given parameters.
		 * 
		 * @param extrusion
		 * @param level
		 */
		void renderExtrusion(ExtrusionStyle extrusion, int level);

		/**
		 * Renders a point of interest circle with the given parameters.
		 * 
		 * @param circle
		 *            the circle.
		 * @param level
		 *            the drawing level on which the circle should be rendered.
		 */
		void renderCircle(CircleStyle circle, int level);

		/**
		 * Renders a point of interest symbol with the given bitmap.
		 * 
		 * @param symbol
		 *            the symbol to be rendered.
		 */
		void renderSymbol(SymbolStyle symbol);

		/**
		 * Renders a way with the given parameters.
		 * 
		 * @param line
		 * @param level
		 */
		void renderWay(LineStyle line, int level);

		/**
		 * Renders a way with the given text along the way path.
		 * 
		 * @param text
		 */
		void renderText(TextStyle text);

	}

	RenderStyle mCurrent = this;
	RenderStyle mNext;
	boolean update;

	public void set(RenderStyle next) {
		update = true;
		mNext = next;
	}

	public void unsetOverride() {
		update = true;
		mNext = null;
	}

	/**
	 * Destroys this RenderInstruction and cleans up all its internal resources.
	 */
	public void dispose() {
	}

	/**
	 * @param renderCallback
	 *            a reference to the receiver of all render callbacks.
	 */
	public void renderNode(Callback renderCallback) {
	}

	/**
	 * @param renderCallback
	 *            a reference to the receiver of all render callbacks.
	 */
	public void renderWay(Callback renderCallback) {
	}

	/**
	 * Scales the text size of this RenderInstruction by the given factor.
	 * 
	 * @param scaleFactor
	 *            the factor by which the text size should be scaled.
	 */
	public void scaleTextSize(float scaleFactor) {
	}

	public void update() {
		if (update) {
			update = false;
			mCurrent = mNext;
		}
	}

	public abstract RenderStyle current();
}