JavaSECanvasState.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.javase;

import java.awt.AlphaComposite;
import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Graphics2D;
import java.awt.geom.AffineTransform;

import loon.canvas.Canvas;
import loon.canvas.Canvas.Composite;
import loon.canvas.Canvas.LineCap;
import loon.canvas.Canvas.LineJoin;

class JavaSECanvasState {

	public interface Clipper {
		void setClip(Graphics2D gfx);
	}

	private static Clipper NOCLIP = new Clipper() {
		@Override
		public void setClip(Graphics2D gfx) {
			gfx.setClip(null);
		}
	};

	int fillColor;
	int strokeColor;
	JavaSEGradient fillGradient;
	JavaSEPattern fillPattern;
	AffineTransform transform;
	float strokeWidth;
	LineCap lineCap;
	LineJoin lineJoin;
	float miterLimit;
	Clipper clipper;
	Composite composite;
	float alpha;

	JavaSECanvasState() {
		this(0xff000000, 0xffffffff, null, null, new AffineTransform(), 1.0f,
				LineCap.SQUARE, LineJoin.MITER, 10.0f, NOCLIP,
				Composite.SRC_OVER, 1);
	}

	JavaSECanvasState(JavaSECanvasState toCopy) {
		this(toCopy.fillColor, toCopy.strokeColor, toCopy.fillGradient,
				toCopy.fillPattern, toCopy.transform, toCopy.strokeWidth,
				toCopy.lineCap, toCopy.lineJoin, toCopy.miterLimit,
				toCopy.clipper, toCopy.composite, toCopy.alpha);
	}

	JavaSECanvasState(int fillColor, int strokeColor,
			JavaSEGradient fillGradient, JavaSEPattern fillPattern,
			AffineTransform transform, float strokeWidth, LineCap lineCap,
			LineJoin lineJoin, float miterLimit, Clipper clipper,
			Composite composite, float alpha) {
		this.fillColor = fillColor;
		this.strokeColor = strokeColor;
		this.fillGradient = fillGradient;
		this.fillPattern = fillPattern;
		this.transform = transform;
		this.strokeWidth = strokeWidth;
		this.lineCap = lineCap;
		this.lineJoin = lineJoin;
		this.miterLimit = miterLimit;
		this.clipper = clipper;
		this.composite = composite;
		this.alpha = alpha;
	}

	void prepareClear(Graphics2D gfx) {
		clipper.setClip(gfx);
	}

	void prepareStroke(Graphics2D gfx) {
		gfx.setStroke(new BasicStroke(strokeWidth, convertLineCap(),
				convertLineJoin(), miterLimit));
		gfx.setColor(convertColor(strokeColor));
		clipper.setClip(gfx);
		gfx.setComposite(convertComposite(composite, alpha));
	}

	void prepareFill(Graphics2D gfx) {
		if (fillGradient != null){
			gfx.setPaint(fillGradient.paint);
		}
		else if (fillPattern != null){
			gfx.setPaint(fillPattern.paint);
		}
		else{
			gfx.setPaint(convertColor(fillColor));
		}
		clipper.setClip(gfx);
		gfx.setComposite(convertComposite(composite, alpha));
	}

	static Color convertColor(int color) {
		float a = (color >>> 24) / 255.0f;
		float r = ((color >>> 16) & 0xff) / 255.0f;
		float g = ((color >>> 8) & 0xff) / 255.0f;
		float b = (color & 0xff) / 255.0f;

		return new Color(r, g, b, a);
	}

	private java.awt.Composite convertComposite(Canvas.Composite composite,
			float alpha) {
		switch (composite) {
		case DST_ATOP:
			return AlphaComposite.DstAtop.derive(alpha);
		case DST_IN:
			return AlphaComposite.DstIn.derive(alpha);
		case DST_OUT:
			return AlphaComposite.DstOut.derive(alpha);
		case DST_OVER:
			return AlphaComposite.DstOver.derive(alpha);
		case SRC:
			return AlphaComposite.Src.derive(alpha);
		case SRC_ATOP:
			return AlphaComposite.SrcAtop.derive(alpha);
		case SRC_IN:
			return AlphaComposite.SrcIn.derive(alpha);
		case SRC_OUT:
			return AlphaComposite.SrcOut.derive(alpha);
		case SRC_OVER:
			return AlphaComposite.SrcOver.derive(alpha);
		case XOR:
			return AlphaComposite.Xor.derive(alpha);
		case MULTIPLY:
			return JavaSEBlendComposite.Multiply.derive(alpha);
		default:
			return AlphaComposite.Src.derive(alpha);
		}
	}

	private int convertLineCap() {
		switch (lineCap) {
		case BUTT:
			return BasicStroke.CAP_BUTT;
		case ROUND:
			return BasicStroke.CAP_ROUND;
		case SQUARE:
			return BasicStroke.CAP_SQUARE;
		}
		return BasicStroke.CAP_SQUARE;
	}

	private int convertLineJoin() {
		switch (lineJoin) {
		case BEVEL:
			return BasicStroke.JOIN_BEVEL;
		case MITER:
			return BasicStroke.JOIN_MITER;
		case ROUND:
			return BasicStroke.JOIN_ROUND;
		}
		return BasicStroke.JOIN_MITER;
	}
}