com.badlogic.gdx.graphics.g2d.PolygonRegion.java Source code

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Here is the source code for com.badlogic.gdx.graphics.g2d.PolygonRegion.java

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/*******************************************************************************
 * Copyright 2011 See AUTHORS file.
 * 
 * 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 com.badlogic.gdx.graphics.g2d;

/** Defines a polygon shape on top of a texture region to avoid drawing transparent pixels.
 * @see PolygonRegionLoader
 * @author Stefan Bachmann
 * @author Nathan Sweet */
public class PolygonRegion {
    final float[] textureCoords; // texture coordinates in atlas coordinates
    final float[] vertices; // pixel coordinates relative to source image.
    final short[] triangles;
    final TextureRegion region;

    /** Creates a PolygonRegion by triangulating the polygon coordinates in vertices and calculates uvs based on that. TextureRegion
     * can come from an atlas.
     * @param region the region used for drawing
     * @param vertices contains 2D polygon coordinates in pixels relative to source region */
    public PolygonRegion(TextureRegion region, float[] vertices, short[] triangles) {
        this.region = region;
        this.vertices = vertices;
        this.triangles = triangles;

        float[] textureCoords = this.textureCoords = new float[vertices.length];
        float u = region.u, v = region.v;
        float uvWidth = region.u2 - u;
        float uvHeight = region.v2 - v;
        int width = region.regionWidth;
        int height = region.regionHeight;
        for (int i = 0, n = vertices.length; i < n; i++) {
            textureCoords[i] = u + uvWidth * (vertices[i] / width);
            i++;
            textureCoords[i] = v + uvHeight * (1 - (vertices[i] / height));
        }
    }

    /** Returns the vertices in local space. */
    public float[] getVertices() {
        return vertices;
    }

    public short[] getTriangles() {
        return triangles;
    }

    public float[] getTextureCoords() {
        return textureCoords;
    }

    public TextureRegion getRegion() {
        return region;
    }
}