dRad - A Discontinuity Meshing Radiosity Solver

Here you can find some info about a discontinuity meshing hierarchical radiosity solver (dRad) written in Visual C++ 6.0 . The program runs under Windows 95, 98, Me, NT, 2000 (and I hope Millenium and 2000 versions) and the only additional dll's that you need are the OpenGL dlls which are already in your system if you are using Windows version other than 95.

Current Version : 1.10 Download dRad

Design and Programming : Ioannis Pantazopoulos <jpanta@softlab.ntua.gr


dRad in Action

Since version 1.00, some minor bugs have been corrected and a gamma correction dialog box has been added. The latter was necessary as the produced images were appearing very dark. To run the program just unzip the file in one directory and just run the executable. With this executable you can load and solve scenes of type .hrt. These are special easy to read files containing info for all triangles and quadrilaterals in the scene. It is easy to code some simple scenes for this format but it is a very strict one (actually I was very concerned with the radiosity simulation and didn't have much time to involve into complex formats). If I have time in the future I will try to make use of widely accepted formats (like mgf) which anyway have increasing object libraries associated with them.

Note that the program has still some bugs and not all of its options work (as this is more a developer tool and not a user tool). When you are running the simulation the first thing that you should do is to define some parameters. Go to Attributes/Radiosity Parameters.

In this menu you will find all the parameters to control the simulation. Note that some configurations do not work (some may even produce crashes). The parameters as set in the beginning are the default parameters so you can directly process a scene without changing any parameter.


Processing a scene:

  1. Load a scene from Files/Open. Choose an .hrt extension and load the appropriate file scene.
  2. Go to Attributes/Radiosity Parameters and change parameters of simulation.
  3. If you would like to have discontinuity meshing press Meshing/Sorted Discontinuities.
  4. Run the simulation by pressing Batch Work in Command option.

In any time while the simulation runs, you can move around the scene using the mouse, the mouse buttons and shift, control buttons on the keyboard. You can also change the view from View option on the menu bar (do not change the Parallel Show - this should be always checked).


Some results (images) of the tool.

Here are some images produced with the tool. I used BF refinement, form factor upper bound 0.2,  energy exchange upper bound 0.04, minimum regular subdivision area 0.1 and minimum surface area 0.0005.

Constant shading of a simple scene.

Constant shading with light discontinuities superimposed.

After the completion of BF refinement, rendered with Gouraud option.

The complete mesh.

Zoom in boxes.

Zoom in table.

Image Thumbnails