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How to calculate the elementary card(map) of light exposure of type Direct Light

Beta the version!

Example of calculation of a card(map) of light exposure (lajtmepa):

• We start program LODka3D.
• We load a file lmhouse01.zip, we unpack it(him) and it is opened through menu Menu-> File-> Open.
  The model is a standard room with two windows, and two columns which often use for demonstration of calculations of schemes(plans) of illumination(coverage).
• We choose in a file the first mesh Mesh1 and the first the Face-group in it(him) Group1.
• We come in the editor of schemes(plans) of illumination(coverage) Menu-> Edit-> Light schemes ... , we are switched to bookmark File. On this bookmark there are schemes(plans) written down in a file. For the given file there there is only one scheme(plan) of illumination(coverage) 4light1, choose it(her) and the editor is closed.
• In the chosen scheme(plan) of illumination(coverage) it is included two light sources. That them to see it is necessary to put tick Menu-> Edit-> Show LigthSources. Then there will be two wire designs showing an arrangement of light sources in space.
• We include a window of the generator lajtmepov. Menu-> Edit-> LightMap generator.
  Here two sections:
  • LigthMap packing - allows to arrange textural coordinates of triangles on a structure so that they did not block each other and on-opportunity adjoined with each other the same sides with which they adjoin in model. That is formed groups.
    Options two:
    • Padding - distance between groups. In pixels. Therefore the size of a structure is important here again.
    • Normals angle is a maximal divergence of normals of triangles that they were considered being in one group. The it is less, the more groups it will be created (if, certainly, it probably). It is set in degrees.
  • Direct Lighting is a type of calculation of a card(map) of light exposure at which dot sources of illumination(coverage) are used. Adjustments(options):
    
    • Calc shadows - whether to count shadows? If is not present, calculation goes much more quickly, but without shadows.
    • Octree accuracy - accuracy at calculation of shadows. That is how much(as far as) the length of the ray of light falling on a point, calculated by means of algorithm Octree can differs from real distance between a light source and a calculated point.
    • Draft - a draft copy. Points successively, and through time are calculated not all. The formed holes are closed an average arithmetic the nearby calculated points. The option is necessary for acceleration.
    • Emission color - color added to all calculated points ( including what are in a shadow. By means of an option lajtmep it is possible to clarify.
    • Texture color - color of a structure in "empty" places. Between ranges.
    • Brightness - brightness of sources of illumination(coverage). The general(common) for all sources. Being a shadow the option does not influence places.
• We choose the size of a structure we shall tell in 1024. We put a tick of shadow Shadows. We choose Emission color, we shall tell grey, we put Brightness in 0.7 . Also we press button Start. Some time will go calculation. Time of calculation depends on speed of work of a computer. Upon termination of calculation it will be possible to press button Log and to look what stage what is the time paid off. Triangles in Direct Light usually longest pay off. Then we close a window and we look result. (see a screenshot)
• That the result is better visible, it is necessary to not forget to disconnect(switch-off) illumination(coverage) Menu-> Edit-> Lightings
• To change parameters of sources of illumination(coverage) it is possible in the editor of schemes(plans) of illumination(coverage) Menu-> Edit-> Light schemes .. . Parameter Shiness (luminescence) - allows to include/disconnect(include/switch-off) the chosen source of illumination(coverage) in the scheme(plan). Parameter Position - sets its(his) position. Parameter Diffusion - color of illumination(coverage). Parameters Const attenuation, Linear attenuation and Quadratic attenuation define(determine) easing light depending on removal(distance) from a source. The factor of easing is calculated under the formula:
  
  k = Const attenuation +Linear attenuation*Distance +Quadratic attenuation*Distance*Distance
  
  Other options are not used.

Consider, that it while only beta.

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