This section contains general information about this manual and Ayam.
As this document is a reference manual, it is probably pointless to read it from the beginning to the end (except maybe for the next section, explaining the basics of the user interface). Instead, just look up the documentation of the things you are interested in via the table of contents or the index. Cross references will then guide you to other important parts of the documentation. Again: this manual has a rather large index, please use it (see section Index)!
This document is organized in the following way:
After this first introductory section, the user interface of Ayam is
explained and basic handling instructions for the application are
given in the second section.
In the third section all interactive modelling actions are documented.
The fourth section details all object types and object properties,
followed by documentation on all NURBS modelling tools in the fifth
section.
In the sixth section the Tcl scripting interface is explained and the
following seventh section has all information about the import and export
plugins.
The eighth section is the dreaded miscellaneous section that
contains documentation not fitting elsewhere.
In this manual, the following typographic conventions are used:
<Ctrl+c> (press control and
c key), for shortcuts like <Ctrl+Shift+t> an abbreviated
version: <Ctrl+T> will be used;"A Name";
set riopt(runtime) { a b }
+-Parent_Object(Type)
| |-First_Child_Object(Type)
| |-Second_Child_Object(Type)
| |-[Third_Child_Object_may_be_present_or_not(Type)]
| |-Empty_Level(Level)
| +-Sub_Level(Level)
| | |-First_Child_Object_of_Sub_Level(Type)
| | \-Last_Child_Object_of_Sub_Level(Type)
| \-Last_Child_Object(Type)
+-Next_Parent_Object(Type)
Ayam is a free 3D modelling environment for the RenderMan Interface, distributed under the modified BSD licence (no advertisement clause).
Ayam is in development since 1997 and was formerly known as
"The Mops". Ayam formed the software base of the
authors PhD work. New versions of Ayam were released in
approximately half year intervals since.
Here is a short summary of the Ayam feature set:
Since Ayam 1.12, dynamic loading of custom objects and certain plugins are also available on the Win32 platform (they were not available before).
Ayam is primarily aimed at the Linux, IRIX, and Win32 platforms. On those platforms BMRT (Blue Moon Rendering Tools, a RenderMan compliant renderer by Larry Gritz) is available. Even though the distribution of BMRT is stopped it is still the recommended renderer for Ayam. Despite of this, Ayam may be used on many more platforms with any RenderMan compliant renderer.
For platforms where BMRT is not available (e.g. FreeBSD or NetBSD), Ayam may be compiled with code from the Affine Toolkit with limited functionality (see also the file INSTALL). In this case, no parsing of slc compiled shaders will be possible.
Since Ayam 1.6 it is also possible to completely replace the BMRT shader parsing and RIB writing code with code from the Aqsis project, thus completely eliminating the need for BMRT. Furthermore, shader parsing plugins are available for all major RenderMan compliant renderers allowing a tight integration of Ayam with any of those renderers.
Ayam uses a right-handed coordinate system as used by OpenGL but as opposed to RenderMan (the latter is using a left-handed coordinate system).
In the default modelling view of type "Front", the positive
X-axis points to the right, the positive Y-axis points upwards
and the Z-axis points outside the screen, to the user.
See also the following image.
All coordinate values in Ayam are dimensionless. It is up to the user to define what a value of 1.0 means: e.g. one centimeter or one meter.
Due to the limited precision of floating point arithmetics used in Ayam, coordinate values should be defined in the range between -10.0 and 10.0 for most accurate results.
Ayam stores rational coordinates in euclidean rational style, i.e. the weight of a control point is not pre-multiplied with the coordinates (this will be done internally when handing the coordinates over for drawing or export purposes).
In Ayam versions prior to 1.19 the weights were always multiplied
with the coordinate values (i.e. homogeneous rational coordinates)
to allow faster drawing with OpenGL/GLU, which expects rational
coordinate values to be delivered this way.
But a negative side effect of this approach was that modification
of coordinates or weights for modelling purposes was unnecessarily
complicated.
Ayam can still display the coordinates in both styles, controlled by
the preference option "RationalPoints" (see also section
Modelling Preferences), but internally
the coordinates are kept in euclidean rational style.
Scene files from older versions of Ayam are converted automatically to the
new rational style when read by Ayam 1.19 and above, but loading of
scene files written by Ayam 1.19 and above into older versions of
Ayam requires manual intervention (e.g. by means of a script).