Re: [Darwin2k-users] How to set base coordinates?

[Chris L. <cl...@te...>]

Marius Andreiana wrote:
> 
> Hi
> 
> I tried without success to set the base coordinates
> somewhere in the lower corner (left or right) of the
> initial window opened by displayCfg.

There are 2 issues here: one is the location of the base, and the other
is the location of the camera in displayCfg.  The attached disp.p file
includes a section for setting the camera location (eyePosX, eyePosY,
eyePosZ) and where it's looking (lookAtX, ...).

> I know the base aramenters are x,y,z coord, then
> unused, then x,y,z size. But why are there 4 numbers
> for each param? What's their meaning?

The 4 numbers for each parameter are:
  min-value  max-value  #-bits  bit-value

min-value and max-value determine the range of values for the parameter;
#-bits specifies the resolution, and bit-value specifies a value from 0
to (2^(#-bits)-1).  The actual parameter value is linearly controlled by
bit-value, i.e. bit-value = 0 indicates a value of min-value, and
bit-value = (2^(#-bits)-1) indicates a value of max-value.  

The parameter format is a bit arcane, because the genetic algorithm
needs to know the min, max, and number of bits, not just the actual
parameter value.  If you're just doing simulation and won't be using the
genetic algorithm, then all of your dimensional parameters (those that
don't select components from the component database) can be of the form:

(0 desired-value 1 1)

which results in the parameter having a value of desired-value.  (This
still works if even if desired-value is < 0). 

I've attached a modified version of bere.l (just changed the first 2
parameters) and disp.p (with added viewing variables) that do roughly
what you're interested in.

Chris