I am trying to render the bodies that I made in the open-source tool using ShapeRenderer.
It seems to work for simple shapes like a square by simply retrieving the vertices and giving them back to the ShapeRenderer. However, when it comes to complex Bodies with about 9 polygons (the one I'm trying to render) I've tried rendering the polygons one by one, but it looks like it's giving me the same polygon over and over again, no matter how I initialize or go through my list of Vector2[]. I've been stuck on this for a while now, and any insight would help. (I'm using the BodyEditorLoader class to get the vertices)
BodyEditorLoader Class where I get my vertices from. (Gotten from open source library)
public class BodyEditorLoader {
// Model
private final Model model;
// Reusable stuff
private final List<Vector2> vectorPool = new ArrayList<Vector2>();
private final PolygonShape polygonShape = new PolygonShape();
private final CircleShape circleShape = new CircleShape();
private final Vector2 vec = new Vector2();
//My stuff
public Vector2[] shapeVertices;
public ArrayList<Vector2[]> polygonModelList = new ArrayList<>();
public List<PolygonModel> polygonModels = new ArrayList<>();
// -------------------------------------------------------------------------
// Ctors
// -------------------------------------------------------------------------
public BodyEditorLoader(FileHandle file) {
if (file == null) throw new NullPointerException("file is null");
model = readJson(file.readString());
}
public BodyEditorLoader(String str) {
if (str == null) throw new NullPointerException("str is null");
model = readJson(str);
}
public void attachFixture(Body body, String name, FixtureDef fd, float
scale,Object data) {
RigidBodyModel rbModel = model.rigidBodies.get(name);
polygonModels = rbModel.polygons;
if (rbModel == null) throw new RuntimeException("Name '" + name + "' was not found.");
Vector2 origin = vec.set(rbModel.origin).scl(scale);
for (int i=0, n=rbModel.polygons.size(); i<n; i++) {
PolygonModel polygon = rbModel.polygons.get(i);
Vector2[] vertices = polygon.buffer;
//Here is were i'm putting the new vertices into an array
polygonModelList.add(vertices);
for (int ii=0, nn=vertices.length; ii<nn; ii++) {
vertices[ii] = newVec().set(polygon.vertices.get(ii)).scl(scale);
vertices[ii].sub(origin);
}
polygonShape.set(vertices);
shapeVertices = vertices;
fd.shape = polygonShape;
Fixture fixture =body.createFixture(fd);
fixture.setUserData(data);
fixture.getBody();
for (int ii=0, nn=vertices.length; ii<nn; ii++) {
free(vertices[ii]);
}
}
System.out.println(rbModel.polygons.size());
for (int i=0, n=rbModel.circles.size(); i<n; i++) {
CircleModel circle = rbModel.circles.get(i);
Vector2 center = newVec().set(circle.center).scl(scale);
float radius = circle.radius * scale;
circleShape.setPosition(center);
circleShape.setRadius(radius);
fd.shape = circleShape;
Fixture fixture = body.createFixture(fd);
fixture.setUserData(data);
free(center);
}
}
//PolygonModel class
public static class PolygonModel {
public final List<Vector2> vertices = new ArrayList<Vector2>();
public Vector2[] buffer; // used to avoid allocation in attachFixture()
}
The code above is not the full class(just because i thought it had a lot of lines) if you'd like to check it out its here: https://github.com/MovingBlocks/box2d-editor/tree/develop/loader-libgdx/src/aurelienribon/bodyeditor
My Structure class
public class Structure {
BodyDef bd;
Body body;
FixtureDef fd;
float x;
float y;
Vector2[] originalShapeVertices;
Vector2[] scaledShapeVertices;
ArrayList<Vector2[]> polygonList = new ArrayList<>();
List<BodyEditorLoader.PolygonModel> polygonModels = new ArrayList<>();
public Structure(float x, float y,World world, BodyEditorLoader bodyEditorLoader)
{
this.x = x;
this.y = y;
bd = new BodyDef();
bd.type = BodyDef.BodyType.StaticBody;
bd.position.set(x,y);
body = world.createBody(bd);
body.setUserData(this);
fd = new FixtureDef();
fd.density = 1;
fd.friction = 1;
fd.restitution = 1;
bodyEditorLoader.attachFixture(body,"Structure",fd,500f,this);
//System.out.println(Arrays.toString(bodyEditorLoader.shapeVertices));
polygonModels = bodyEditorLoader.polygonModels;
initVerticesFromModel();
}
public void initVerticesFromModel()
{
for (BodyEditorLoader.PolygonModel model : polygonModels) {
polygonList.add(model.buffer);
}
}
public float[] getPolygonVectors(Vector2 [] vertices)
{
float[] copiedVertices = new float[vertices.length * 2];
for (int i=0, j=0; i<copiedVertices.length; i+=2,j++)
{
copiedVertices[i] = vertices[j].x;
copiedVertices[i+1] = vertices[j].y;
}
return copiedVertices;
}
public Vector2[] getScaledShapeVertices(Vector2[] originalShapeVertices)
{
Vector2[] scaledShapeVertices = new Vector2[originalShapeVertices.length];
for (int i=0; i<scaledShapeVertices.length; i++)
{
Vector2 newVertex = new Vector2(originalShapeVertices[i].x+body.getPosition().x,originalShapeVertices[i].y+body.getPosition().y);
scaledShapeVertices[i] = newVertex;
}
return scaledShapeVertices;
}
public Line2D.Float[] getBodySegments()
{
Vector2[] vertices = scaledShapeVertices;
Line2D.Float[] segments = new Line2D.Float[vertices.length];
for (int i =0; i<segments.length; i++)
{
int nextPoint = i+1;
if (nextPoint >= segments.length)
{
nextPoint = segments.length-1;
segments[i] = new Line2D.Float(vertices[nextPoint].x,vertices[nextPoint].y,vertices[0].x,vertices[0].y);
}
else {
segments[i] = new Line2D.Float(vertices[i].x, vertices[i].y, vertices[nextPoint].x, vertices[nextPoint].y);
}
}
return segments;
}
}
Finally How I render it using ShapeRenderer
Structure demo = new Structure(200,100,world,structureLoader);
@public void render()
{
shapeRenderer.setProjectionMatrix(camera.combined);
shapeRenderer.begin(ShapeRenderer.ShapeType.Line);
for(int i =0; i<9; i++) {
float[]polygon =
demo.getPolygonVectors(demo.getScaledShapeVertices(demo.polygonList.get(i)));
shapeRenderer.polygon(polygon);
}
shapeRenderer.end();
}
question from:
https://stackoverflow.com/questions/65946881/rendering-complex-bodies-in-libgdx 
