Log 5 : Blueprint node,normal computation, Cell clipping…

Categories Dissertation

Hi there,

Last days I figured out some problematic bugs like the plane representation conflict between UE4 and CGAL. Now I successfully extract the plane normal from each voronoi cell facet which allow me to begin the development of the main fracture routine witch is the fragment construction !

ue4editor_2016-11-15_22-12-33The plane representation for debug

After computing the plane equation inside CGAL ( Based on this example), I make a blueprint library inside the fracture plugin to manage and debug all future BP function in real-time.



Some BP in the new blueprint lib…

Finally I start to wrote the fragment generation procedure I order to cut the target object following the fracture pattern. Here are some test in WIP…

ue4editor_2016-11-19_19-20-37 ue4editor_2016-11-19_19-18-45
irst attempt to generate the fracture fragments a runtime

Report 4 : Code refactoring, convex hull computation, plane equation

Categories Dissertation

I spend the last weekend fixing a dynamic linking bug in the CGAL plugin which prevented me from computing the convex hull of the voronoi cells… My mistake was loading the GMP and MPRF Dll’s as DelayedDLL and not in the startup module function while the module loading.

Me Sunday night…

After fixing that issue, I continued the fracture plugin development by refactor the voronoi region detection,  computing the convex hull of each cell then the plane equation of each cells plane.

b06c7d4b-1eb9-4b98-8462-ca136aac6febThe voronoi region convex hulls in wire-frame…

aa3073b9-d060-40af-a429-1229ed877ae5One voronoi region convex hulls in wire-frame…

Tomorrow : display and make plane inside UE4 in order to play with slice function. The problem it that CGAL and UE4 don’t have the same plane construction equation… To be continued 🙂

Report 3 : CGAL Plugin, Voronoi Diagram(VD) Display

Categories Dissertation

Last day I put CGAL inside a plugin to improve it’s flexibility: now, you just have to put the plguin to install CGAL in your project.

ue4editor_2016-11-07_23-27-56CGAL unreal plugin 🙂

I also started to play with the lib and took some hour to find how to access to the VD data… But finally I display my first VD inside unreal successfully !

First_vd_ue4First Voronoi diagram !

Next step : Code rewriting ( Find a proper way to implement the VD in order to move it in real time)


Report 2: CGAL unreal integration

Categories Dissertation

I spend these two last evenings trying to compile and link CGAL with Unreal Engine and finally I did it ! I will post a tutorial soon to explain the setup from scratch.

ue4editor_2016-11-02_23-51-31A simple CGAL test, display if different points are collinear using the lib.

The corresponding code into UE4

Now I start the prototyping stage, test to make a  simple voronoi diagram and display it, then I will try to intersect these cells with a simple cube mesh from UE4 to generate destructible mesh.

Report 1

Categories Dissertation

Today I defined a little timeline(see image below) to determine how I’ll proceed. 

Currently I have almost done the State of art, found a lot of interesting papers about real-time destruction and extract a “general fracture procedure” ( I will post a schema tomorrow 😉 )
I go into testing and prototyping with CGAL library which is a very complete geometry tool suit !



First tetrahedralisation test with CGAL 


Categories Dissertation

Hi, it’s been a while since I have’nt published anythings because of my studies… I’ll try to post as soon as possible 🙂 . Currently I am in search of my dissertation subject, for now I retain two differents :

  • Raymarching : How to include raymarched object into a modern game engine ? How to interact with it ?
  • Geometry : How to make a convincing fracture in real-time ?

Today I go toward the Geometry subject (But keep  the raymarching one in my pocket just in case…) and made a state of art to see where I’m going 🙂


Day 17: Basic noise

Categories AShaderEveryDay

        Today I decided to set aside the ray marching engine to focus on GLSL’s basic like procedural  texture generation witch will be very unseful for the sphere tracing later 🙂 . To make this noise the formula is simple ;  you compute the sinus (sin(x)) of a dot of two 2D vectors , then you took the fractional part (fract(x)in GLSL) of the result. To resume is look like this :

float random (vec2 st) {
    return fract(sin(dot(st.xy,vec2(13.4,74.0)))*(83983.0));

First noise… 🙂

Day 15 : First texture

Categories AShaderEveryDay

Finally I had not enough time to start voxel’s learning, I will do that this weekend. So I started an approach of texturing.. 🙂 Update tonight !

First  procedural texture test
(click on  play to start animation )