LibGDX BOX2D changes maxPolygonVertices

Question

I need to create a body with more than 8 vertices, and I get an error.

AL lib: (EE) alc_cleanup: 1 device not closed Assertion failed! Program: C:\Program Files\Java\jre7\bin\javaw.exe File: /var/lib/jenkins/workspace/libgdx/gdx/jni/Box2D/Collision/Shapes/b2PolygonShape.cpp, Line 122 Expression: 3 <= count && count <= 8 

How can I change this constant?

I found this file https://github.com/libgdx/libgdx/blob/master/gdx/jni/Box2D/Common/b2Settings.h

Here i saw

 #define b2_maxPolygonVertices 8 

How can I change it from libGDX?

Answer 1

Actually, you should not change this, as this will reduce performance.

Instead, you will create a Body with several Fixtures . These fixtures will have a maximum of 8 vertices and will share some of the vertices, so you will simulate a large figure using smaller parts that stick together.

This is called polygonal decomposition. Some Box2D editors do this automatically for you when you export your scene. Probably the best editor for Box2D is RUBE . There is also a libgdx loader for rube scenes here .

If you create them programmatically, you may have to do it yourself. Perhaps some LibGDX tools, such as EarClippingTriangulator , may help you here.