"white_dune" is a continuation of the "dune" project by Stephan F. White.
"dune" is a graphical VRML97/X3D Editor, simple NURBS modeller and animation
tool with some OpenGL scene rendering capabilities.
In princple, the structure of the white_dune program can be written as:
The GUI of white_dune consists of 2 parts:
The 2D GUI mainloop of white_dune is event driven. Typical events are
mouse-movement, mouse-click, resize of window and so on.
Additionally the mainloop can produce timer events.
When a event occures, the matching callback function is started.
The callbacks work for every subwindow of white_dune.
The following image shows the subwindows (red text) of the mainwindow.
A additional callback OnUpdate is used to distribute
messages like UPDATE_FIELD or UPDATE_ADD_NODE to the
child classes of SceneView. OnUpdate is started by
the function UpdateViews of class Scene.
Some operations require additional input of data. Then a "Dialog"
is opened, that block the data input to all other windows.
The class Scene (Scene.h/cpp) can be identified with one VRML/X3D file. For example Scene.write() writes the VRML/X3D file to disk.
The global variable TheApp of class DuneApp (DuneApp.h/cpp) can be identified with things that are global to all VRML/X3D files.
The internals of each VRML/X3D Node are implemented in the files named NodeNodeName (for example NodeTransform (NodeTransform.h/cpp), NodeShape (NodeShape.h/cpp) or NodeBox (NodeBox.h/cpp)).
Every NodeNodeName.h file contain 2 classes: the
class NodeNodeName which contain functionality
like draw() for 3D rendering of shapes and the class
ProtoNodeName which are used to build the definitions
of the VRML97 standard.
For example, the definiton of the Transform Node in
the ISO/IEC 14772 standard
is implemented in the constructor of the class ProtoTransform
(in file NodeTransform.cpp):
ProtoTransform::ProtoTransform(Scene *scene)
: Proto(scene, "Transform")
{
addEventIn(MFNODE, "addChildren");
addEventIn(MFNODE, "removeChildren");
center.set(addExposedField(SFVEC3F, "center", new SFVec3f(0.0f, 0.0f, 0.0f)));
children.set (addExposedField(MFNODE, "children", new MFNode(), CHILD_NODE));
rotation.set(addExposedField(SFROTATION, "rotation", new SFRotation(0.0f, 0.0f, 1.0f, 0.0f)));
scale.set(addExposedField(SFVEC3F, "scale", new SFVec3f(1.0f, 1.0f, 1.0f), new SFFloat(0.0f)));
scaleOrientation.set(addExposedField(SFROTATION, "scaleOrientation",new SFRotation(0.0f, 0.0f, 1.0f, 0.0f)));
translation.set(addExposedField(SFVEC3F, "translation", new SFVec3f(0.0f, 0.0f, 0.0f)));
bboxCenter.set(addField(SFVEC3F, "bboxCenter", new SFVec3f(0, 0, 0)));
bboxSize.set(addField(SFVEC3F, "bboxSize", new SFVec3f(-1, -1, -1), new SFFloat(-1.0f)));
}
Different fields are internally handled as integer values.| SFVec3f * | center (void) |
| void | center (SFVec3f *value) |
| void | center (SFVec3f &value) |
| int | center_Field (void) |
Functionality common to all Nodes (like writing a Node to a file (Node.write())
is in the class Node (file Node.h/cpp). All NodeNodeName classes are
subclasses of the class Node.
Some of the memberfunctions of the class Node are virtual and can be
overwritten by the NodeNodeName classes (for example, the
class NodeScript need a special version of Node.write()).
Here is a list of important virtual Node memberfunctions:
The class "FieldValue" is used to set the data of the nodes.
The wellknown VRML/X3D types like SFFloat, MFVec3f, SFString etc. are
subclasses of the "FieldValue" class.
When setting data of the nodes, it is important that the old data is
always deallocated using the "delete" command.
The constructor of "MF-type" data (like MFVec3f, MFInt32, MFString etc.)
never copy the data array, it reuses the data via a pointer.
Therefore
it is not possible to use "automatic" variables (like
"float data[30]") to initalise MF-type data directly. When the
automatic variable is removed from the memory, the data inside the
node is also lost and it is likely, that a crash would occure.
Wrong example:
{
float data[20];
...
MFFloat data4node = new MFFloat(data, 20);
...
someNode->setField(fieldName_Field(), data4node);
...
} // someNode.fieldName gets invalid cause memory is freed at this point
A other example of automatic variable usage uses a internal white_dune
data type like "array", "list" etc.:
{
Array data;
...
data.append(1.0f);
...
data.append(42.0f);
...
MFFloat data4node = new MFFloat(data.getData(), data.size());
...
someNode->setField(fieldName_Field(), data4node);
...
} // someNode.fieldName gets invalid cause memory is freed at this point
The correct way uses "new"
{
float* data = new float[20];
...
MFFloat data4node = new MFFloat(data, 20);
...
someNode->setField(fieldName_Field(), data4node);
...
} // someNode.fieldName ok
Path overview
As Path is a class that holds the path to a node in the Scenegraph or
in a PROTO. The path in the Scenegraph is mainly a integer array of
the fields containing the SFNode or MFNode field of the next node
(one integer) and the index of the next MFNode field (or 0 in case of a
SNode field) (another integer).
If path[0] is less than zero, the path is inside a PROTO. A path[0] == -1
is inside the first PROTO, a path[0] == -2 is inside the second proto,
a path[0] == -3 is inside the third PROTO etc.
In case of a PROTO, path[1] contains the number of the root node of the PROTO:
path[1] == 0 is the path beginning with the first root node, path[1] == 1 is
the path beginning with the second root node, path[1] == 2 is the path
beginning with the third root node.
PROTO overview
Proto is the PROTO interface (ProtoDeclare or ExternProtoDeclare) or
Node interface. Node::getProto() gets the node interface.
NodePROTO is a ProtoInstance or ExternProtoInstance.
ExternProtoDeclare is a ProtoDeclare with variable "url" set.
VRML97/X3D parser
Dune need to read and parse ("understand") VRML97 or X3DV files.
This is done with using the tools lex/yacc (it looks like, the advanced
tools flex and bison from the GNU project are needed).
The file lexer.l do the lexical analysis (detect things like "what is
a string", "what is a number", "what is that VRML97 or X3D keyword").
The file parser.y do the grammatical analysis (detect and prove, if the
tokens found by the lexical analysis form valid VRML/X3DV contructions
(like Node or ROUTE statements). If some tokens of the grammar are valid,
the action part of the command in the parser.y file create the matching
VRML Nodes, Numbers etc.
Thanks to Doug Sanden, white_dune can also parse XML encoded X3D files.
This is done via the expat library.
Dangerous constructs
The buildin stringtype ("MyString") can be misleading, it act very
pointerlike. For example be carefull about constructs like the following:
MyString str = node->getProto()->getName();
str += "something"; // also appended to the name...
This do not only copy the name of a Proto of "node" to str and append
"something" to it, it also appends "something" to the name of a Proto !
In this situation, it is better to use something like
MyString str = strdup(node->getProto()->getName());
str += "something";
or
MyString str = "";
str += node->getProto()->getName();
str += "something";
Another dangerous constructs are the constructors for MF* types with pointers
to multiple data of the basic datatype. This is already described
in a chapter above.
"Adding a new node to white_dune"-cookbook
MENUITEM "Something", ID_NEW_SOMETHINGin the matching submenu of the POPUP "&Create" menu and and
ID_NEW_SOMETHING "Create a new Something Scripted PROTO\nSomething Scripted"
to all src/dune.*.rc files. See the chapter about
localisation for more informations about handling the needed language
translations.
addOrReplace(protos, "Something", new ProtoSomething(scene), add);in a matching place (sorted by the alphabet of the SOMETHING in the list in Node.h) in the function SceneProtoMap::createProtoMap and add
#include "NodeSomething.h"to SceneProtoMap.cpp
{ DUNE_SOMETHING, ID_NEW_SOMETHING, true, true },
(you may replace DUNE_SOMETHING with VRML_SOMETHING or X3D_SOMETHING)
to the matching NodeButton arrays in MainWindow.cpp
{ DUNE_SOMETHING, ID_NEW_SOMETHING, false, true },
to MainWindows.cpp and add something like
case DUNE_SOMETHING:
valid = node->findValidFieldType(VRML_REQUIRED_BY_SOMETHING) != -1;
break;
to the swich in MainWindow::UpdateToolbar(STOOLBAR toolbar, Node *node,
int field, NodeButton *buttons, int count)
sh batch/inserticon.sh DUNE_SOMETHING
or
sh batch/inserticon.sh X3D_SOMETHING
gimp will then open and select the matching node icons that has to be
moved 16 pixels to left. Use "edit->cut" and "edit->paste" then move
the icons to the left border of the gimp window. Draw your new icon
in the new 16 pixels wide white gap.
case ID_NEW_SOMETHING:
CreateNode("Something");
break;
to MainWindow::OnCommand(int id) in MainWindow.cpp
White_dune is able to write the VRML97/X3D scenegraph data in the programming
languages C, C++ and java. The resulting data can be used in other programs,
e.g. to render the data with a own OpenGL program. There are a lot of visable
nodes in VRML97/X3D, so there is away to convert primitive (e.g. Box) or
parametric (e.g. NurbsPatchSurface) shapes to mesh data. It is also possible
to convert to triangulated mesh data. All visible shapes classes (except
shape classes not rendered by white_dune yet and the class of the "Text" node)
are children of the MeshBasedNode class, which handles the conversion.
Animateable shapes (like Nurbs(Patch)Surface) are children of the
MeshMorphingNode class, which is able to create morphing animation data
for the resulting mesh data. The MeshMorphingNode class is also a child
of the MeshBasedNode class.
White_dune can also directly write the needed java sourcecode to render
VRML97/X3D data in the Open Wonderland multiuser server.
This includes features like animation, scripting and interaction.
See the man page of white_dune
for more information.
Unfortunatly, there are a lot of nodes, which are not supported by
the wonderland exporter. Each node can be written as a java class, but it
makes a remarkable difference to the java compiler (with respect to
memory usage and compile time) if the classes of the unsupported nodes
are written or not. Therefore, the optimization option to avoid unsupported
nodes is now per default in use. Unsupported nodes found in the X3D file
are also written, but developers who wish to implement the support for
such a node may need either always switch off the optimization or
mark this node as supported by the Wonderland exporter in the white_dune
sources.
The interface of a node is defined in class named e.g. "ProtoSomeNodeName"
in the file NodeSomeNodeName.cpp.
The "ProtoSomeNodeName" class is a (direct or indirect) child of a class named
"Proto". To mark a node as supported by the Wonderland exporter replace the
"Proto" class name in the ProtoSomeNodeName definition
class SomeNodeName : public Proto {
class SomeNodeName : public WonderlandExportProto {
It requires absolute no programming skills to translate the program to a
foreign language, if the foreign languages uses ASCII characters:
you only need to copy the file "src/dune.english.rc" into a similar file,
use a texteditor with search and replace und at end translate the strings
in this file to the foreign language.
The problems when trying to translate the program to a foreign language with non ASCII characters (like chinease UTF8 characters) are untested/unknown.
To complete the task to create a new runnable program a compatible compiler
is needed. Of course, this task can be done (after publicing the main
translation file src/dune.something.rc) by a programmer later, it do not need to
be done by the translator.
All "src/dune.*.rc" files are copied together into one src/dune.rc file during the
run of "configure" and "make".
This means, that for creating a new runnable program, you need either a
UNIX like system (e.g. Linux or MacOSX) or a bunch of unixtools:
m4, make, cat, grep and sh (e.g. bash or ksh).
A complete free/opensource installable collection of unixtools for M$Windows
is called cygwin and is available for free from the internet.
For Translaton, first search the ISO 3166 two characters of your language (e.g. "en" for english, "de" for german, "it" for italian, etc...) and build the uppercase version of this characters (e.g. EN for english, DE for german, IT for italian, etc).
Second, select a src/dune.something.rc file. In the simpler case, do not select
"src/dune.english.rc" cause this requires more complicated search and replace
commands.
Third you need to translate all the strings in the new src/dune.something.rc file.
A so called string is a term that starts with a " and ends with a "
For example, the translation of the line from src/dune.english.rc
POPUP "&File"
to german language in src/dune.german.rc would result in
POPUP "&Datei"
where the german word Datei is the translation of the english word File.
The "&" sign marks the keyboard shortcut. The next character after "&"
should not be ambient in the same level of a menu.
After the translation of the strings is ready, the translation step is
ready. On a Linux/UNIX/MacOSX/cygwin system with the gawk (GNU awk) program
you can use
sh test/testmenus.shone the commandline to use some consistency testing of the new rc file.
The new file src/dune.something.rc can be now publiced (e.g. in a usenet group like comp.lang.vrml, or at the sourceforge site for the original dune project).
For a recompilation, you first need to extend the list of lanugages,
white_dune understands.
Currently you need to extend the list of known languages in the file
src/swt/include/languages.m4. E.g. to extend the list of known
languages from english (empty default) and german (DE) in
src/swt/include/languages.m4
define(`M4_LANGUAGES_CONFIG',` DE,german')to english, italian (IT) and german, then change the list to
define(`M4_LANGUAGES_CONFIG',` IT,italian, DE,german')or extent to english, italian and spanish (ES) and german, then change the list to
define(`M4_LANGUAGES_CONFIG',` IT,italian, ES,spanish, DE,german')Take care that the last language line (here with "DE,german") do not end with a comma.
It is also possible to change the yes/no strings in Linux/UNIX messageboxes.
E.g. you extend the yes/no strings from english and german in
src/swt/include/languages.m4
define(M4_YES_english,"yes") define(M4_YES_german,"Ja") define(M4_NO_english,"no") define(M4_NO_german,"Nein")with the yes/no strings of italian, you have to change src/swt/include/languages.m4 to
define(M4_YES_english,"yes") define(M4_YES_italian,"si") define(M4_YES_german,"Ja") define(M4_NO_english,"no") define(M4_NO_italian,"no") define(M4_NO_german,"Nein")
The final step is rebuilding the needed files for compilation. On a
Linux/UNIX/MacOSX/cygwin system, this is done automatically by using
"sh build.sh"
(or "configure && make").
On other systems, at least a text editor and a port of the m4 program is
required.
With the texteditor, copy all dune.*.rc files together and store the
result in the file "dune.rc"
With m4 you need to execute the following commands in the src directory:
m4 resource.h.m4 > resource.h
m4 CommandlineLanguages.h.m4 > CommandlineLanguages.h
After recompilation (see the file INSTALL for details), the new language can
be used with a commandline parameter.
The name of the new commandline parameter is the minus sign followed by
the second word in the new line in M4_LANGUAGES_CONFIG.
E.g. if you added "IT,italian," to M4_LANGUAGES_CONFIG, the new commandline
parameter to switch to the italien language is -italien
All that have to be done now is to add the new commandline parameter to the documentation in the manpage file man/dune.1
When handling text messages from a programmers point of view, always try to use the function "swLoadString" to get a language related string (e.g. for a errormessage) from the "src/dune.rc" file. The first argument of the swLoadString file is a identifier, like IDS_INTERNAL_ERROR, which refers to the message in the default (english) language. To get the current language translation, add the term TheApp->getLang() to the idenifier, e.g . with swLoadString(IDS_INTERNAL_ERROR + TheApp->getLang(),...
As a programmer, take care about the fact, that each program code
modification (e.g. addition of new menu items) in one of the
src/dune.something.rc
files requires the change of a all other "src/dune.somelanguage.rc" files.
Cause a programmer is usually not a multilingual genius, the addition of
a new menuitem, icon tooltip or errormessage comes with a translation
problem. There are two possible solutions: either use a dictionary/internet
translation service like babelfish.altavista.com, or leave the english
word in the src/dune.something.rc file and hope for modification by users.
To leave the line blank cause of a unknown foreign word is not a option,
cause this can result in a crash of the program when used in this foreign
language.
The addition of a new icon tooltip or errormessage also requires the
inclusion of a new "#define" command which can be usually found in the
resource.h file.
Do not change the resource.h file directly. The file resource.h is a
autogenerated file, that could be overwritten at each run of the "make"
command or "configure" command.
The name of most sourcefiles in the "src" directory is identical to the name of the major contained class.
The following class/filenames have special meanings:
If doxygen
is installed, a class hierarchy of white_dune can be produced by typing
make documentation
and can then be found here.