IT'S NOT A BUG IT'S A ...


There are holes in my isosurface, or it doesn't appear at all. 
Try setting max_gradient higher.


Parametric isosurfaces run about 50 times slower than MegaPOV.
Side effect of the removal of interval arithmetic.


Not all functions are available for use within user defined functions.
E.g. val(), rand() are not available.
The list of available functions is documented in 6.1.6.


My isosurface disappears half way through the render.
Crackle pigments are not suitable for use in isosurfaces.


Isosurface renders differently to MegaPOV.
This may be due to the fact that MegaPOV handled the square roots of
negative values incorrectly.


Some of the pigments in woods.inc look horrible.
Some of the pigments, such as "P_WoodGrain4B" are intended to be used in
conjunction with colour_maps from woodmaps.inc. With the default
colour_map they look weird.
Many of the pigments just happen to look OK because the default
colour_map for the wood pigment pattern consists of shades of brown.


The help system often leaves temporary files in Windows\temp.
Blame MicroSoft.


Within a function, "x" sometimes means "the x co-ordinate of the current
point" and sometimes means the vector <1,0,0>.
When the syntax demands a vector, "x" is interpreted as "<1,0,0,>".


Texture_map can't have more than 256 entries.
It's a limitation.


"diffuse" doesn't accept functions.
(Well, technically, you could use a float function to calculate the
diffuse value for an object, but you get a single value that applies to
the whole object.)
It's a limitation.


New noise generator isn't very random.
You shouldn't really be trying to use noise as a random number generator
(use rand() instead), even though the old noise generator did work quite
well.


Artefacts appear on the surface of a distant torus.
It's a limitation of the floating point accuracy of your computer. The
torus primitive uses a fourth order equation, so it fails first.


Isosurface intersections and merges (& and |) are the wrong way round in
beta 8
They were the wrong way round before. The beta 8 way is considered
correct.

-- 
Mike Williams
Gentleman of Leisure

Post a reply to this message