user3340001 user3340001 - 1 month ago 21
Java Question

ShapeRenderer produces pixelated shapes using LibGDX

When I use a ShapeRenderer, it always comes out pixelated. But if I draw the shape in photoshop with the same dimensions, it's very smooth and clean-looking.

My method is just as follows:


import com.badlogic.gdx.Gdx;
import com.badlogic.gdx.scenes.scene2d.Actor;

public class bub_actors extends Actor {
private ShapeRenderer shapes;
private Texture text;
private Sprite sprite;

public bub_actors(){
shapes = new ShapeRenderer();
text = new Texture(Gdx.files.internal("data/circle.png"));
sprite = new Sprite();
public void draw(SpriteBatch batch, float parentAlpha) {
batch.draw(sprite, 200, 200, 64, 64);
shapes.filledCircle(50, 50, 32);

Here's an image of the output:

enter image description here

Any ideas as to why this happens? Is it possible to make the ShapeRenderer look like the image (so I don't have to create a SpriteBatch of different-colored circles...).


The difference is anti-aliasing that Photoshop applies to the image it generates. If you zoom in on the edges of the two circles, you'll see the anti-aliased one has some semi-black pixels around the edge, where the ShapeRenderer generated circle just shows pixels entirely on or off.

anti-aliased image

aliased image

The Libgdx ShapeRenderer was designed for being a quick and simple way to get debugging shapes on the screen, it does not support anti-aliasing. The easiest way to get consistent anti-aliased rendering it to use a texture. (Its also possible with an OpenGL shader.)

That said, you do not have to create different sprites just to render different colored circles. Just use a white circle with a transparent background, and then render it with a color. (Assuming you want a variety of solid-colored circles).