使用 libGDX 以编程方式绘制漂亮的线条

Question

In my libGDX project I have to draw such lines:

It may have various number of vertices. Currently I'm just adding it to stage as a texture with transparent background. And if I have a lot of such lines, it takes quite a lot of space in atlases. So I want to draw these polygonal chains programmatically using libGDX. I don't have much time and will to write my own libraries to achieve this, so I'm interested is some existing solutions. Two questions:

1. I've found that a line could be drawn using ShapeRenderer.rectLine(). Now how can add some shades, glowing, rounded ends, gradients, etc to make it look better? Or do I have to implement all this on my own?
2. I suppose that the answer is no, but still - is there a neat way to multiply some small texture along a line? Thanks.

Answer 1

For this case, I think this might be the best way to do this, but take in mind that using OpenGL with Stage is not the easiest way to solve it...

On the other hand, an easier, but probably not that "beautiful" nor the faster way to solve it, could be using a TextureRegionDrawable, and scale, rotate and move for each point in your line path.

I wrote a little class, at least for a reference, it will need some polish, specially with corners.

public class LineDrawer extends Actor {
    private Array<Vector2> path;
    private float thickness;
    private Image image;

    public LineDrawer(Array<Vector2> path, float thickness, TextureRegionDrawable drawable) {
        this.path = path;
        this.thickness = thickness;
        this.image = new Image(drawable);
        this.image.setOrigin(Align.left);
    }

    @Override
    public void draw(Batch batch, float parentAlpha) {
        float dst, angle;
        Vector2 pointA, pointB;
        for (int i = 0; i < path.size - 1; i++) {
            pointA = path.get(i);
            pointB = path.get(i + 1);
            dst = pointA.dst(pointB);
            angle = MathUtils.atan2(pointB.y - pointA.y, pointB.x - pointA.x) * 180f / MathUtils.PI;

            image.setSize(dst, thickness);
            image.setPosition(pointA.x, pointA.y, Align.left);
            image.setRotation(angle);

            image.draw(batch, parentAlpha);
        }
    }
}