LibGdx使用模板测试

一个图片中显示出一个⚪
1.开始模板测试

config.stencil = 8;   //开启莫把测试

2.绘制

public class SeneTest extends Group {

    private SpineActor spineActor;
    private Cir cir;
    public SeneTest(){
        cir = new Cir(300,300,200);
        addActor(cir);
        spineActor = new SpineActor("spine/countrypic/Australia/Australia");
        addActor(spineActor);
        spineActor.setPosition(20,100, Align.center);
        spineActor.setAnimation("1",true);
    }

    @Override
    public void draw(Batch batch, float parentAlpha) {
        batch.flush();
        Gdx.gl.glEnable(GL20.GL_STENCIL_TEST);
        Gdx.gl.glStencilOp(GL20.GL_KEEP, GL20.GL_KEEP, GL20.GL_REPLACE);//第一次绘制的像素的模版值 0+1 = 1
        Gdx.gl.glStencilFunc(GL20.GL_ALWAYS, 1, 0xFF);
        cir.draw(batch,parentAlpha);
        Gdx.gl.glStencilFunc(GL20.GL_EQUAL, 0x1, 0xFF);//等于1 通过测试 ,就是上次绘制的图 的范围 才通过测试。
        Gdx.gl.glStencilOp(GL20.GL_KEEP, GL20.GL_KEEP, GL20.GL_KEEP);//没有通过测试的，保留原来的，也就是保留上一次的值。
        spineActor.draw(batch,parentAlpha);
        batch.flush();
        Gdx.gl.glDisable(Gdx.gl.GL_STENCIL_TEST);
    }
}

3.cir

public class Cir extends Actor {
    private float centerX;
    private float centerY;
    private float radius;
    private ShapeRenderer sr;

    public Cir(float x, float y, float radius) {
        this.centerX = x;
        this.centerY = y;
        this.radius = radius;
        setPosition(centerX - radius, centerY - radius);
        setSize(radius * 2, radius * 2);
        sr = new ShapeRenderer();
    }

    @Override
    public void act(float delta) {
        super.act(delta);
    }

    @Override
    public void draw(Batch batch, float parentAlpha) {
        super.draw(batch, parentAlpha);
        if (sr != null) {
            batch.end();
            sr.setProjectionMatrix(batch.getProjectionMatrix());
            sr.setTransformMatrix(batch.getTransformMatrix());
            sr.setColor(Color.valueOf("FFFFFF00"));
            sr.begin(ShapeRenderer.ShapeType.Filled);
            sr.circle(centerX, centerY, radius);
            sr.end();
            batch.begin();
        }
    }

    public void setRadius(float radius) {
        this.radius = radius;
    }

    public float getRadius() {
        return radius;
    }
}

效果:

image.png