LTB-Light 31 Oct 2013

Natural and artificial lighting calculation.


Developer website: LTB Soft

LTB-Light is an application that permits natural and artificial lighting calculation with a color radiosity method applied to a finite elements plan.

LTB-Light runs under Apple Mac and implements OpenGL.

Data management take places through an internal powerful CAD system, directly in a perspective view. It is possible to introduce flatten surfaces with colored glazing, furniture, curved surfaces like cylinders, cones, ellipsoids, hyperboloids and complex objects like cross vaults.

LTB-Light is able to share information with other CADs through DXF and PICT files.

Light sources are totally managed inside the main program; it is possible to import, show, modify and use the IESNA LM-63 photometric data files (ASCII text file commonly used by North American lighting fixture manufacturers) EULUMDAT (european standard) and even PICT files (the program can convert a drawing in a photometry!); photometric data are modelled through 36 "C" (azimuth) curves and 181 "gamma" (zenith) angles, while lamp color is controlled by its color temperature or RGB color. Calculations permits to control levels of illuminations, allocated energy amounts, correct positioning of light sources (type, numbers, power,...), direct and reflected colors.

LTB-Light results (Horizontal, vertical along X+,Y+,X-,Y- directions, semi-cylindrical and main camera-direction Illuminament; Luminances; Daylight Factors; RGB coordinates; Contrast control C.R.F.; Glare control TI, G, U.G.R., C.G.I. and G.R.; Lighting Pollution) will be presented in black and white, 8-colors or true-colors perspective view for the whole model and for every object in the scene.

For every object in the scene it will be possible to have also planar-projected mapping with values-mapping and/or curves-mapping overlapped. It is also possible to print or export these results as TEXT, Formatted Text (RTF), PICT, DXF file or by "copy-paste" procedures, and to export the RTF-formatted estimation of the whole project (fixtures, wires and special pieces) in the implemented currencies.

LTB-Light has a series of powerful tools that permit to optimize Your projects: a 'CIE module' to precalculate the needs of simple rectangular room and a 'Road tool' to find the best roads installation as regards fixtures, pole distance and height.


  • 3D interactive workspace environment with full use of OpenGL and a native Mac OS X interface
  • Shares information with other CAD via DXF and PICT files
  • Uses standard IESNA LM-63 photometric data files (USA) and EULUMDAT (Europe)
  • Controls Illumination levels, energy, sources specs
  • Output in various standard format
  • Many powerful tools inside

What's New

  • Implemented road optimization tool;
  • add menu with road lighting class following EN13201;
  • select special: add pop-menu to select all elements in a layer;
  • in the drawer button for creating userface, emptyhole, opaquehole, dim, wire added;
  • export report: possible to save more than one 'quality parameter' row;
  • Face and Road dialogue: add sidewalks fields;
  • add Menu 'Pointing surface';
  • preferences: add possibiliti to copy minimal data from result analisys;
  • drawer: add pop menu for quick results examination;
  • snap and view line barycenter;
  • lighting source manager: scale photometry field support 4 operation;
  • search in lighting sources lists up to 2 strings separated by '+' (logic AND);
  • CIE dialogue: add quinconce layout;
  • scroll view through mouse wheel;
  • drawer: add Length and Azimuth fields;
  • DXF import blocks;
  • two lines automatic trim;
  • incremented number of possible holes in a face: 101;
  • CIE and AREA ialogue: source rotation added;
  • add object 'torus'.
  • bug fixed


OS X 10.5.8 or later


Current Version (9.x)


Version Downloads
Education / Science
31 Oct 2013
OS X / Intel 32