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javalibgdxbox2d

Box2d Body filled with a texture Libgdx

I have a simple triangular shape (obstacle) in my game and i would like to fill it with a texture repeatedly. I have looked at the other 2 topics but couldn't find a working solution. How can i fill this triangle with a small image (assume that its called "brickTexture.png" repeatedly? Here is the code for creating the box2dbody of the obstacle in Obstacle.java

BodyDef bdef = new BodyDef();
bdef.position.set(obstaclePosition);
bdef.type = BodyDef.BodyType.StaticBody;
b2body = world.createBody(bdef);

FixtureDef fdef = new FixtureDef();
PolygonShape triangle = new PolygonShape();
float vertices1[] ={-50 / PPM, 100 / PPM,
                    50 / PPM, 100 / PPM,
                     0 / PPM,  0 / PPM};
triangle.set(vertices1);

fdef.shape = triangle;
b2body.createFixture(fdef);

And this is the triangle

enter image description here

Solution

  • This can easily be achieved by using the classes PolygonRegion and PolygonSpriteBatch and will work for any polygonal shape (not just triangles).

    Create the polygon region:

    // this will calculate the triangles given your vertices
short triangles[] = new EarClippingTriangulator().computeTriangles(vertices1).toArray();
// use your texture region
PolygonRegion polygonRegion = new PolygonRegion(textureRegion, vertices1, triangles);

    Then you need to use the PolygonSpriteBatch to render at the desired position (I presume body position):

    polygonSpriteBatch.draw(polygonRegion, x, y);

    Make sure you load your texture with Repeat wrap so it can tile:

    texture.setWrap(Texture.TextureWrap.Repeat, Texture.TextureWrap.Repeat);

    Class docs: PolygonRegion, EarClippingTriangulator, PolygonSpriteBatch