forplay.html.HtmlPath.java Source code

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Here is the source code for forplay.html.HtmlPath.java

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/**
 * Copyright 2010 The ForPlay 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.
 */
package forplay.html;

import com.google.gwt.canvas.dom.client.Context2d;
import com.google.gwt.core.client.JsArrayNumber;

import forplay.core.Asserts;
import forplay.core.Path;

class HtmlPath implements Path {

    private static final int CMD_ARC = 3;
    private static final int CMD_CLOSE = 4;
    private static final int CMD_LINE = 1;
    private static final int CMD_MOVE = 0;
    private static final int CMD_QUAD = 2;

    private JsArrayNumber list = JsArrayNumber.createArray().cast();

    @Override
    public void arcTo(float radius, float x, float y) {
        list.push(CMD_ARC);
        list.push(radius);
        list.push(x);
        list.push(y);
    }

    @Override
    public void close() {
        list.push(CMD_CLOSE);
    }

    @Override
    public void lineTo(float x, float y) {
        list.push(CMD_LINE);
        list.push(x);
        list.push(y);
    }

    @Override
    public void moveTo(float x, float y) {
        list.push(CMD_MOVE);
        list.push(x);
        list.push(y);
    }

    @Override
    public void quadraticCurveTo(float cpx, float cpy, float x, float y) {
        list.push(CMD_QUAD);
        list.push(cpx);
        list.push(cpy);
        list.push(x);
        list.push(y);
    }

    @Override
    public void reset() {
        list.setLength(0);
    }

    void replay(Context2d ctx) {
        ctx.beginPath();

        int len = list.length(), i = 0;
        double x = 0, y = 0;
        while (i < len) {
            switch ((int) list.get(i++)) {
            case CMD_MOVE: {
                x = list.get(i++);
                y = list.get(i++);
                ctx.moveTo(x, y);
                break;
            }
            case CMD_LINE: {
                x = list.get(i++);
                y = list.get(i++);
                ctx.lineTo(x, y);
                break;
            }
            case CMD_QUAD: {
                double cpx = list.get(i++);
                double cpy = list.get(i++);
                x = list.get(i++);
                y = list.get(i++);
                ctx.quadraticCurveTo(cpx, cpy, x, y);
                break;
            }
            case CMD_ARC: {
                double curX = x, curY = 0;
                double radius = list.get(i++);
                x = list.get(i++);
                y = list.get(i++);
                ctx.arcTo(curX, curY, x, y, radius);
                break;
            }
            case CMD_CLOSE: {
                ctx.closePath();
                break;
            }

            default:
                throw new AssertionError("Corrupt command list");
            }
        }
    }

    float[] getVertices() {
        int len = list.length();
        Asserts.check(len % 2 == 0);
        float[] vertices = new float[len];
        for (int v = 0; v < len;) {
            int cmd = (int) list.get(v);
            if (v == vertices.length - 2) {
                Asserts.check(cmd == CMD_CLOSE);
            } else {
                Asserts.check(cmd == CMD_MOVE);
            }
            vertices[v] = (float) list.get(v + 1);
            vertices[v + 1] = (float) list.get(v + 2);
        }
        return vertices;
    }

    void replay(Path path) {
        path.reset();

        int len = list.length(), i = 0;
        float x = 0, y = 0;
        while (i < len) {
            switch ((int) list.get(i++)) {
            case CMD_MOVE: {
                x = (float) list.get(i++);
                y = (float) list.get(i++);
                path.moveTo(x, y);
                break;
            }
            case CMD_LINE: {
                x = (float) list.get(i++);
                y = (float) list.get(i++);
                path.lineTo(x, y);
                break;
            }
            case CMD_QUAD: {
                float cpx = (float) list.get(i++);
                float cpy = (float) list.get(i++);
                x = (float) list.get(i++);
                y = (float) list.get(i++);
                path.quadraticCurveTo(cpx, cpy, x, y);
                break;
            }
            case CMD_ARC: {
                float radius = (float) list.get(i++);
                x = (float) list.get(i++);
                y = (float) list.get(i++);
                path.arcTo(x, y, radius);
                break;
            }
            case CMD_CLOSE: {
                path.close();
                break;
            }

            default:
                throw new AssertionError("Corrupt command list");
            }
        }

    }
}