[Libgdx] Problem with ImmediateModeRenderer20

Engines, Libraries and Tools
#1

When I draw a polygon with ImmediateModeRenderer20 and on the next frame I draw it with an offset the polygon becomes noisy.How I can fix this?

#2
  1. Please show some code, I don’t get what you’re doing ^^
  2. A screenshot can be really helpful for us to understand what you mean with “noisy”.

Also, ImmediateModeRenderer20 is deprecated. You shouldn’t use it. You should use one of the following:
[x] SpriteBatch for rendering Textured, moving images
[x] ShapeRenderer for rendering Shapes without textures (circles, lines, rectangles)
[x] SpriteCache for rendering Textured, static images like scenery

#3

Well I want to render the background which is 20MB and I want to use vertices.[20MB per level]

#4 

public class LevelBackground {
	private ImmediateModeRenderer20 renderer;
	private Texture backgroundText;
	private Matrix4 projMatrix;
	private Body terrainBody;
	private ChainShape line;
	private BodyDef lineBodyDef;
	private ArrayList<Vector2> terrainVectors;
	private double dots[];
	private int speed;
	private Camera camera;

	

	public LevelBackground(String name,double dots[], World world,
			Camera camera,int speed) {
		this.camera = camera;
		this.speed = speed;
		this.dots = dots;
		projMatrix = new Matrix4();
		renderer = new ImmediateModeRenderer20( true, true, 1);
		backgroundText = new Texture(
				(Gdx.files.internal(name)),false);
		backgroundText.setFilter(TextureFilter.Linear, TextureFilter.Linear);
		line = new ChainShape();
		lineBodyDef = new BodyDef();
		terrainVectors = new ArrayList<Vector2>();
		lineBodyDef.position.set(0, 0);
		lineBodyDef.type = BodyType.StaticBody;
		// terrainBody = world.createBody(lineBodyDef);
		// for (int i = 0; i < floats.length; i++) {
		// terrainVectors.add(screenToPhysics(camera, new Vector2(
		// i * 100f - 50f, (float) ((floats[i]) / 2f) + 220f)));
		// }
		// line.createChain(terrainVectors.toArray(new Vector2[terrainVectors
		// .size()]));
		// for (int i = 0; i < terrainBody.getFixtureList().size; i++) {
		// terrainBody.getFixtureList().get(i).setFriction(1f);
		// }
		// terrainBody.createFixture(line, 1f);
	}

	public void render(float offset) {
		backgroundText.bind(GL20.GL_TEXTURE_2D);
		renderer.begin(projMatrix, GL20.GL_TRIANGLE_STRIP);
		Gdx.app.log("size", "" + dots.length);
		for (float i = 0; i < dots.length; i++) {
			renderer.texCoord((i%2),1f);
			renderer.color(1f, 1f, 1f, 1f);
			renderer.vertex(i / (float) (dots.length) * 2 - 1.5f - offset
					/ (float)speed, (float) ((dots[(int) (i)]) / 900f) - 0.8f, 1f);
			renderer.texCoord(0f, 0f);

			renderer.color(1f, 1f, 1f, 1f);
			renderer.vertex(i / (float) (dots.length) *2 - 1.5f - offset
					/ (float)speed, -1f, 1f);

		}
		renderer.end();
	}

	private Vector2 screenToPhysics(Camera camera, Vector2 screenPos) {
		Vector3 worldPos = new Vector3(screenPos.x, screenPos.y, 0);
		camera.unproject(worldPos);

		return new Vector2(worldPos.x, worldPos.y).scl(1f / 32f);
	}
}

The problem whith the noise is that the texture don`t move smooth through the screen but at fixed intervals .I use a very detailed texture and this step movement create the effect of noise.

#5

That is not noise, well it kind of is. You are probably experiencing aliasing.

If your image is very detailed, say 5000x5000 and your screen is only 1920x1080. A lot of the 1 pixel thick details will be lost.

A way around it is texture filtering, using texture.setFilter();

If it is a very detailed image though, you can only do so much.

#6

Well the texture is 100 by 100 and the device is 1280x756 but I think that I place the vertices too close.