PixMap

package com.mygdx.game;

import com.badlogic.gdx.ApplicationAdapter;
import com.badlogic.gdx.Gdx;
import com.badlogic.gdx.graphics.Color;
import com.badlogic.gdx.graphics.GL20;
import com.badlogic.gdx.graphics.Pixmap;
import com.badlogic.gdx.graphics.Texture;
import com.badlogic.gdx.graphics.g2d.SpriteBatch;
import com.badlogic.gdx.math.Vector2;

public class MyGdxGame extends ApplicationAdapter {

    private Vector2 touch;
    private Vector2 preTouch;
    private Pixmap pixmap;
    private SpriteBatch batch;
    private Texture img;
    private int radius;

    @Override
    public void create() {
        touch = new Vector2();
        preTouch = new Vector2();
        pixmap = new Pixmap(800, 800, Pixmap.Format.RGBA8888);
        pixmap.setColor(Color.ORANGE);
        pixmap.drawCircle(300, 300, 30);
        pixmap.fillCircle(100, 100, 50);
        batch = new SpriteBatch();
        img = new Texture(pixmap);
        radius = 8;
    }

    @Override
    public void render() {
        update();
        Gdx.gl.glClear(GL20.GL_COLOR_BUFFER_BIT);
        batch.begin();
        batch.draw(img, 0, 0);
        img.draw(pixmap, 0, 0);
        batch.end();
    }

    private void update() {
        getTouch();
        draw();
    }

    private void draw() {
        if (touch.x < 0) return;
        pixmap.fillCircle((int) touch.x, (int) touch.y, radius);
    }

    public Vector2 getTouch() {
        preTouch.set(touch);
        if (Gdx.input.isTouched())
            touch.set(Gdx.input.getX(), Gdx.input.getY());
        else touch.set(-1000, -1000);
        return touch;
    }

    @Override
    public void dispose() {
        batch.dispose();
        img.dispose();
    }
}