* display bokeh sample pattern, add bokeh shape, improve look
draw sample pattern to texture and display in ui to see number of samples and their arrangment
add bokeh shape controls
remove adhoc 'sqrt' pattern since display makes existing pattern easier to understand and it looks nicer.
switch to floating point color texture and leave lighting results in linear space until after dof is performed. provides better results and bright spots can make more noticeable bokeh shapes.
change default values to use take more samples at reduced resolution so initial experience when loading the sample is better looking image
* update screenshot, minor change to ui
fix height of ui element so scrollbar not required by default layout
update screenshot
* fix typo in texturev
atleast, i'm pretty sure that's a typo don't see a reason to set width twice
