[Bf-blender-cvs] CVS commit: blender/source/blender/blenkernel/intern world.c blender/source/blender/blenloader/intern readfile.c blender/source/blender/makesdna DNA_world_types.h blender/source/blender/render/intern/source rendercore.c blender/source/blender/renderconverter/intern convertBlenderScene.c blender/source/blender/src buttons_shading.c

[Ton Roosendaal]

ton (Ton Roosendaal) 2003/12/30 19:03:37 CET

  Modified files:
    blender/source/blender/blenkernel/intern world.c 
    blender/source/blender/blenloader/intern readfile.c 
    blender/source/blender/makesdna DNA_world_types.h 
    blender/source/blender/render/intern/source rendercore.c 
    blender/source/blender/renderconverter/intern 
                                                  convertBlenderScene.c 
    blender/source/blender/src buttons_shading.c 
  
  Log:
  Added improved exposure calculation
  
  - based at 1.0-exp(-color) trick in Yafray. But to guarantee backwards
    compatibility, and some more control, Stefano Selleri hacked a useful
    formula for it.
  - We now have 2 values to set:
    - "exp": the exponential correction value (0-1)
    - "range": the light range that maps on color 1.0 (0-5)
  - Using exp(x) (is e^x) we can much better prevent overflows from render,
    which are currently hard-clipped in Blender. Setting a small 'exp' value
    wil efficiently smooth out high energy and map that back to a color for
    display.
  - total formula:
    newcol= linfac*(1.0-exp(col*logfac))
      col, newcol are colors
    linfac= 1.0 + 1.0/((2.0*wrld.exp +0.5)^10)
    logfac= log( (linfac-1.0)/linfac )/wrld.range
      wrld.exp and wrld.range are the button values
  - default setting: exp=0.0 and range=1.0 give results extremely close to
    previous rendering.
  - graph: http://www.selleri.org/Blender/buffer/Image1.png  for 'exp' setting
    ranging from 0-1, and with 'range'=2
  
  Thanks Stefano for the help!
  
  Revision  Changes    Path
  1.7       +10 -4     blender/source/blender/blenkernel/intern/world.c
  1.38      +10 -1     blender/source/blender/blenloader/intern/readfile.c
  1.6       +8 -4      blender/source/blender/makesdna/DNA_world_types.h
  1.34      +13 -4     blender/source/blender/render/intern/source/rendercore.c
  1.23      +2 -2      blender/source/blender/renderconverter/intern/convertBlenderScene.c
  1.52      +7 -4      blender/source/blender/src/buttons_shading.c