Option to run a function in a module rather then a script from a python controller, this has a number of advantages.
- No allocating and freeing the namespace dictionary for every time its triggered
(hard to measure the overhead here, but in a test with calling 42240 scripts a second each defining 200 vars, using modules was ~25% faster)
- Ability to use external python scripts for game logic.
- Convenient debug option that lets you edit scripts while the game engine runs.
PyObjectPlus::ProcessReplica() is now called when any of its subclasses are replicated.
This is important because PyObjectPlus::ProcessReplica() NULL's the 'm_proxy' python pointer I added recently.
Without this a replicated subclass of PyObjectPlus could have an invalid pointer (crashing the BGE).
This change also means CValue::AddDataToReplica() can be moved into CValue::ProcessReplica() since ProcessReplica is always called.
Some functions used
ProcessReplica(replica);
others
replica->ProcessReplica()
Use the second method everywhere so the PyObjectPlus's ProcessReplica() can be called from its subclasses.
Note that PyObjectPlus's ProcessReplica isnt used yet.
Realtime modifiers applied on mesh objects will be supported in
the game engine with the following limitations:
- Only real time modifiers are supported (basically all of them!)
- Virtual modifiers resulting from parenting are not supported:
armature, curve, lattice. You can still use these modifiers
(armature is really not recommended) but in non parent mode.
The BGE has it's own parenting capability for armature.
- Modifiers are computed on the host (using blender modifier
stack).
- Modifiers are statically evaluated: any possible time dependency
in the modifiers is not supported (don't know enough about
modifiers to be more specific).
- Modifiers are reevaluated if the underlying mesh is deformed
due to shape action or armature action. Beware that this is
very CPU intensive; modifiers should really be used for static
objects only.
- Physics is still based on the original mesh: if you have a
mirror modifier, the physic shape will be limited to one half
of the resulting object. Therefore, the modifiers should
preferably be used on graphic objects.
- Scripts have no access to the modified mesh.
- Modifiers that are based on objects interaction (boolean,..)
will not be dependent on the objects position in the GE.
What you see in the 3D view is what you get in the GE regardless
on the object position, velocity, etc.
Besides that, the feature is compatible with all the BGE features
that affect meshes: armature action, shape action, relace mesh,
VideoTexture, add object, dupligroup.
Known problems:
- This feature is a bit hacky: the BGE uses the derived mesh draw
functions to display the object. This drawing method is a
bit slow and is not 100% compatible with the BGE. There may
be some problems in multi-texture mode: the multi-texture
coordinates are not sent to the GPU.
Texface and GLSL on the other hand should be fully supported.
- Culling is still based on the extend of the original mesh.
If you have a modifer that extends the size of the mesh,
the object may disappear while still in the view frustrum.
- Derived mesh is not shared between replicas.
The derived mesh is allocated and computed for each object
with modifiers, regardless if they are static replicas.
- Display list are not created on objects with modifiers.
I should be able to fix the above problems before release.
However, the feature is already useful for game development.
Once you are ready to release the game, you can apply the modifiers
to get back display list support and mesh sharing capability.
MSVC, scons, Cmake, makefile updated.
Enjoy
/benoit
Separate getting a normal attribute and getting __dict__, was having to do too a check for __dict__ on each class (multiple times per getattro call from python) when its not used that often.
- More verbose error messages.
- BL_Shader wasnt setting error messages on some errors
- FilterNormal depth attribute was checking for float which is bad because scripts often expect ints assigned to float attributes.
- Added a check to PyVecTo for a tuple rather then always using a generic python sequence. On my system this is over 2x faster with an optmized build.
- comments to PyObjectPlus.h
- remove unused/commented junk.
- renamed PyDestructor to py_base_dealloc for consistency
- all the PyTypeObject's were still using the sizeof() their class, can use sizeof(PyObjectPlus_Proxy) now which is smaller too.
This changes how the BGE classes and Python work together, which hasnt changed since blender went opensource.
The main difference is PyObjectPlus - the base class for most game engine classes, no longer inherit from PyObject, and cannot be cast to a PyObject.
This has the advantage that the BGE does not have to keep 2 reference counts valid for C++ and Python.
Previously C++ classes would never be freed while python held a reference, however this reference could be problematic eg: a GameObject that isnt in a scene anymore should not be used by python, doing so could even crash blender in some cases.
Instead PyObjectPlus has a member "PyObject *m_proxy" which is lazily initialized when python needs it. m_proxy reference counts are managed by python, though it should never be freed while the C++ class exists since it holds a reference to avoid making and freeing it all the time.
When the C++ class is free'd it sets the m_proxy reference to NULL, If python accesses this variable it will raise a RuntimeError, (check the isValid attribute to see if its valid without raising an error).
- This replaces the m_zombie bool and IsZombie() tests added recently.
In python return values that used to be..
return value->AddRef();
Are now
return value->GetProxy();
or...
return value->NewProxy(true); // true means python owns this C++ value which will be deleted when the PyObject is freed
Hiding faces is a editing option like selection and should not change rendering, it wasn't even working right because meshes without UVs ignored it.
I thought this was needed for compatibility with old files but just noticed this messes up 2 of the files in demos-2.42.zip
- fix for multiple viewpors broke single viewport (both work now)
- python could get uninitialized values from m_prevTargetPoint and m_prevSourcePoint
- getting the RayDirection for python could crash blender trying to normalize a zero length vector.
- added python attributes
- removed unused canvas from the MouseFocusSensor class
Clamp objects min/max velocity.
Accessed with bullet physics from the advanced button with dynamic and rigid body objects.
- useful for preventing unstable physics in cases where objects move too fast.
- can add linear velocity with the motion actuator to give smooth motion transitions, without moving too fast.
- minimum velocity means objects don't stop moving.
- python scripts can adjust these values speedup or throttle velocity in the existing direction.
Also made copy properties from an object with no properties work (in case you want to clear all props)
Added occlusion culling capability in the BGE.
More info: http://wiki.blender.org/index.php/Dev:Ref/Release_Notes/2.49/Game_Engine#BGE_Scenegraph_improvement
MSVC, scons, cmake, Makefile updated.
Other minor performance improvements:
- The rasterizer was computing the openGL model matrix of the objects too many times
- DBVT view frustrum culling was not properly culling behind the near plane:
Large objects behind the camera were sent to the GPU
- Remove all references to mesh split/join feature as it is not yet functional
- Only try and remove light objects from the light list.
- Only loop over mesh verts once when getting the bounding box
- dont return None from python attribute localInertia when theres no physics objects. better return a vector still.
- add names to send message PyArg_ParseTuple functions.
This commit contains a number of performance improvements for the
BGE in the Scenegraph (parent relation between objects in the
scene) and view frustrum culling.
The scenegraph improvement consists in avoiding position update
if the object has not moved since last update and the removal
of redundant updates and synchronization with the physics engine.
The view frustrum culling improvement consists in using the DBVT
broadphase facility of Bullet to build a tree of graphical objects
in the scene. The elements of the tree are Aabb boxes (Aligned
Axis Bounding Boxes) enclosing the objects. This provides good
precision in closed and opened scenes. This new culling system
is enabled by default but just in case, it can be disabled with
a button in the World settings. There is no do_version in this
commit but it will be added before the 2.49 release. For now you
must manually enable the DBVT culling option in World settings
when you open an old file.
The above improvements speed up scenegraph and culling up to 5x.
However, this performance improvement is only visible when
you have hundreds or thousands of objects.
The main interest of the DBVT tree is to allow easy occlusion
culling and automatic LOD system. This will be the object of further
improvements.
Use each types dictionary to store attributes PyAttributeDef's so it uses pythons hash lookup (which it was already doing for methods) rather then doing a string lookup on the array each time.
This also means attributes can be found in the type without having to do a dir() on the instance.
- Raised limit of 2 axis to 4 axis pairs (4==8 joysticks axis pairs)
- Added a new Joystick Sensor type "Single Axis", so you can detect horizontal or vertical movement, rather then just Up/Down/Left/Right
- added Python attribute "axisSingle" so you can get the value from the selected axis (rather then getting it out of the axis list)
- renamed Py attribute "axisPosition" to "axisValues" (was never in a release)
If we need to increase the axis limit again just change JOYAXIS_MAX and the button limits.
- action attribute wasnt checking for NULL (own fault)
- KX_Scene getCamera wasnt checking for NULL
- CListValue had asserts for not yet implimented functionality, this would close blender. Better to print an error if the user manages to run this functions (I managed to by CListValue.count([1,2,3]))
- Initialize python types with PyType_Ready, which adds methods to the type dictionary.
- use Pythons get/setattro (uses a python string for the attribute rather then char*). Using basic C strings seems nice but internally python converts them to python strings and discards them for most functions that accept char arrays.
- Method lookups use the PyTypes dictionary (should be faster then Py_FindMethod)
- Renamed __getattr -> py_base_getattro, _getattr -> py_getattro, __repr -> py_base_repr, py_delattro, py_getattro_self etc.
From here is possible to put all the parent classes methods into each python types dictionary to avoid nested lookups (api has 4 levels of lookups in some places), tested this but its not ready yet.
Simple tests for getting a method within a loop show this to be between 0.5 and 3.2x faster then using Py_FindMethod()
Added the method into the PyType so python knows about the methods (its supposed to work this way).
This means in the future the api can use PyType_Ready() to store the methods in the types dictionary.
Python3 removes Py_FindMethod and we should not be using it anyway since its not that efficient.
Notes:
* Sequence transform strip uses G.scene global, this is commented
out now, should be fixed.
* Etch-a-ton code was most difficult to merge. The files already in
2.5 got merged, but no new files were added. Calls to these files
are commented out with "XXX etch-a-ton". editarmature.c and
transform_snap.c were complex to merge. Martin, please check?
* Game engine compiles and links again here for scons/make/cmake
(player still fails to link).
Previously only the first collision would trigger an event (no collisions a negative event ofcourse)
With the Pulse option enabled, any change to the set of colliding objects will trigger an event.
Added this because there was no way to count how many sheep were on a platform in YoFrankie without running a script periodically.
Changes in collision are detected by comparing the number of objects colliding with the last event, as well as a hash made from the object pointers.
Also changed the touch sensors internal list of colliding objects to only contain objects that match the property or material.
- pulse isnt a great name, could change this.
* Where possible use vec.setValue(x,y,z) to assign values to a vector instead of vec= MT_Vector3(x,y,z), for MT_Point and MT_Matrix types too.
* Comparing TexVerts was creating 10 MT_Vector types - instead compare as floats.
* Added SG_Spatial::SetWorldFromLocalTransform() since the local transform is use for world transform in some cases.
* removed some unneeded vars from UpdateChildCoordinates functions
* Py API - Mouse, Ray, Radar sensors - use PyObjectFrom(vec) rather then filling the lists in each function. Use METH_NOARGS for get*() functions.
- variables that shadow vers declared earlier
- Py_Fatal print an error to the stderr
- gcc was complaining about the order of initialized vars (for classes)
- const return values for ints and bools didnt do anything.
- braces for ambiguous if statements
Assorted smaller fixes:
- Fix: modal keymaps for editmode in view3d were not set again
when you copy areas or go fullscreen.
- Improved "redo last op" (F6) to search back in history for
a redoable operator. Operator also used wrong pupmenu type.
- On creating new FCurve editor, the channel rainbow colors are
set correct.
- EditMesh: fixed code for Spin/Screw, correct props, init and
error reporting. (Spin hotkey ALT+R temporary)
- recompiled all to check for uninitialized variable warnings.
(compile flag should be -O for this). Fixed some proto's.
Use 'const char *' rather then the C++ 'STR_String' type for the attribute identifier of python attributes.
Each attribute and method access from python was allocating and freeing the string.
A simple test with getting an attribute a loop shows this speeds up attribute lookups a bit over 2x.
View3D has been split now in a local part (RegionView3D) and a
per-area part (old View3D). Currently local is:
- view transform
- camera zoom/offset
- gpencil (todo)
- custom clipping planes
Rest is in Area still, like active camera, draw type, layers,
localview, custom centers, around-settings, transform widget,
gridlines, and so on (mostly stuff as available in header).
To see it work; also added new feature for region split,
press SHIFT+ALT+CTRL+S for four-split.
The idea is to make a preset 4-split, configured to stick
to top/right/front views for three views.
Another cool idea to explore is to then box-clip all drawing
based on these 3 views.
Note about the code:
- currently view3d still stores some depricated settings, to
convert from older files. Not all settings are copied over
though, like custom clip planes or the 'lock view to object'.
- since some view3d ops are now on area level, the operators
for it should keep track of that.
Bugfix in transform: quat initialize in operator-invoke missed
one zero.
Als brought back GE to compile for missing Ipos and channels.
Think global, act local!
The old favorite G.scene gone! Man... that took almost 2 days.
Also removed G.curscreen and G.edbo.
Not everything could get solved; here's some notes.
- modifiers now store current scene in ModifierData. This is not
meant for permanent, but it can probably stick there until we
cleaned the anim system and depsgraph to cope better with
timing issues.
- Game engine G.scene should become an argument for staring it.
Didn't solve this yet.
- Texture nodes should get scene cfra, but the current implementation
is too tightly wrapped to do it easily.
svn merge https://svn.blender.org/svnroot/bf-blender/trunk/blender -r12987:17416
Issues:
* GHOST/X11 had conflicting changes. Some code was added in 2.5, which was
later added in trunk also, but reverted partially, specifically revision
16683. I have left out this reversion in the 2.5 branch since I think it is
needed there.
http://projects.blender.org/plugins/scmsvn/viewcvs.php?view=rev&root=bf-blender&revision=16683
* Scons had various conflicting changes, I decided to go with trunk version
for everything except priorities and some library renaming.
* In creator.c, there were various fixes and fixes for fixes related to the -w
-W and -p options. In 2.5 -w and -W is not coded yet, and -p is done
differently. Since this is changed so much, and I don't think those fixes
would be needed in 2.5, I've left them out.
* Also in creator.c: there was code for a python bugfix where the screen was not
initialized when running with -P. The code that initializes the screen there
I had to disable, that can't work in 2.5 anymore but left it commented as a
reminder.
Further I had to disable some new function calls. using src/ and python/, as
was done already in this branch, disabled function calls:
* bpath.c: error reporting
* BME_conversions.c: editmesh conversion functions.
* SHD_dynamic: disabled almost completely, there is no python/.
* KX_PythonInit.cpp and Ketsji/ build files: Mathutils is not there, disabled.
* text.c: clipboard copy call.
* object.c: OB_SUPPORT_MATERIAL.
* DerivedMesh.c and subsurf_ccg, stipple_quarttone.
Still to be done:
* Go over files and functions that were moved to a different location but could
still use changes that were done in trunk.
* use SDL events to trigger the sensor, trigger was being forced every tick. removed workaround for this problem.
* added "All Events" option, similar to all keys in the keyboard sensor.
This means every event from the joystick will trigger the sensor, however only events from the selected type (axis/button/hat) is used to set the positive state of the sensor.
* Added python function sens_joy.GetButtonValues(), returns a list of pressed button indicies.
* Removed pressed/released option for joystick buttons, it was the same as the invert option.
object message actuators needed the prefix OB when sending a message to a specific object.--This line, and those below, will be ignored--
M source/gameengine/Converter/KX_ConvertActuators.cpp
M source/blender/blenkernel/BKE_blender.h
M source/blender/src/buttons_logic.c
M source/blender/blenloader/intern/readfile.c
A new type of constraint actuator is available: Force field.
It provides a very similar service to the Fh material feature
but with some specificities:
- It is defined at the object level: each object can have
different settings and you don't need to use material.
- It can be applied in all 6 directions and not just -Z.
- It can be enabled/disabled easily (it's an actuator).
- You can have multiple force fields active at the same time
on the same object in different direction (think of a
space ship in a tunnel with a repulsive force field
on each wall).
- You can have a different damping for the rotation.
Besides that it provides the same dynamic behavior and the
parameters are self explanatory.
It works by adapting the linear and angular velocity: the
dynamic is independent of the mass. It is compatible with
all other motion actuators.
Note: linear and anysotropic friction is not yet implemented,
the only friction will come from the object damping parameters.
Support for friction will be added in a future revision.
1) Anisotropic friction works for static and dynamic objects
2) For soft bodies, assume triangle mesh if no bounds a chosen
3) Form factor == inertia scaling factor, it was actually hooked up in Bullet
4) Only show 'radius' if sphere is chosen, or no bounds+dynamics (== sphere bounds)
add -nojoystick commandline option: it takes 5 seconds everytime to start the game engine, while there IS no joystick.
In other words: blender -noaudio -nojoystick improves workflow turnaround times for P - ESC from 7 seconds to 1 second!
Improved Bullet soft body advanced options, still work-in-progress. Make sure to create game Bullet soft bodies from scratch, it is not compatible with last weeks builds.
Added Bullet/Gimpact concave collision detection to Blender. If your build system isn't updated yet, please add extern/bullet2/src/BulletCollision/Gimpact/*
This allows moving/dynamic concave triangle meshes (decomposing meshes into compound convex shapes, and using 'compound' shapes is still preferred)
Three features that were on the main UI interface are now
moved to the Advanced Settings panel:
Margin, Actor (that becomes Sensor Actor) and No sleeping.
Sensor Actor is now a feature: it can be turned on and off
for all types of objects, and not just static objects.
Select the Sensor Actor button to make the object visible
to Near and Radar sensor.
The button is selected by default for dynamic objects
and unselected by default for static objects, to match
previous behavior.
correct if there was more than one camera. It shoots rays from the
active camera, but used the viewport from whichever camera was drawn
last, now it uses the correct vieport.
but don't have an action got the pose of already added armatures, even
though they're not related. This also fixes an issue where the armature
in Blender would end up in the pose from the game after ESC, removes
unneeded copies made during armature evaluation, and also solves the
constraint copying hack.
The Physics button controls the creation of a physics representation
of the object when starting the game. If the button is not selected,
the object is a pure graphical object with no physics representation
and all the other physics buttons are hidden.
Selecting this button gives access to the usual physics buttons.
The physics button is enabled by default to match previous Blender
behavior.
The margin parameter allows to control the collision margin from
the UI. Previously, this parameter was only accessible through
Python. By default, the collision margin is set to 0.0 on static
objects and 0.06 on dynamic objects.
To maintain compatibility with older games, the collision margin
is set to 0.06 on all objects when loading older blend file.
Note about the collision algorithms in Bullet 2.71
--------------------------------------------------
Bullet 2.71 handles the collision margin differently than Bullet 2.53
(the previous Bullet version in Blender). The collision margin is
now kept "inside" the object for box, sphere and cylinder bound
shapes. This means that two objects bound to any of these shape will
come in close contact when colliding.
The static mesh, convex hull and cone shapes still have their
collision margin "outside" the object, which leaves a space of 1
or 2 times the collision margin between objects.
The situation with Bullet 2.53 was more complicated, generally
leading to more space between objects, except for box-box collisions.
This means that running a old game under Bullet 2.71 may cause
visual problems, especially if the objects are small. You can fix
these problems by changing some visual aspect of the objects:
center, shape, size, position of children, etc.
The 'opposite' of the "Insert Key" tool.
- Use the hotkey Ctrl-Alt-IKEY to activate.
- Only available in 3d-view and buttons window
I've added an extra var to verify_ipo and verify_ipocurve to save having to make another duplicate of that code. Hopefully the gameengine compiles ok with this.
player did not enable mipmapping when falling back to texfaces.
Also commented out code that disabled mipmapping in the player on
Mac OS X. If that is a workaround for a bug it is a really poor one,
and hopefully fixed now since this code is from 2002 or earlier.
* Fix issue with add transparency mode with blender materials.
* Possible fix at frontface flip in the game engine.
* Fix color buffering clearing for multiple viewports, it used
to clear as if there was one.
* Fix for zoom level in user defined viewports, it was based on
the full window before, now it is based on the viewport itself.
* For user defined viewports, always use Expose instead of
Letterbox with bars, the latter doesn't make sense then.
saves a marshal'd GameLogic.globalDict to the blendfile path with the blend extension replaced with bgeconf
Use this in YoFrankie to save keyboard layout and graphics quality settings.
I'm getting this error now:
GPG_Application.cpp: In member function 'void GPG_Application::stopEngine()':
/System/Library/Frameworks/Python.framework/Versions/2.3/include/python2.3/marshal.h:12: error: too many arguments to function 'PyObject* PyMarshal_WriteObjectToString(PyObject*)'
GPG_Application.cpp:720: error: at this point in file
Are we offically not supporint older versions of python now? :)
Kent
the features that are needed to run the game. Compile tested with
scons, make, but not cmake, that seems to have an issue not related
to these changes. The changes include:
* GLSL support in the viewport and game engine, enable in the game
menu in textured draw mode.
* Synced and merged part of the duplicated blender and gameengine/
gameplayer drawing code.
* Further refactoring of game engine drawing code, especially mesh
storage changed a lot.
* Optimizations in game engine armatures to avoid recomputations.
* A python function to get the framerate estimate in game.
* An option take object color into account in materials.
* An option to restrict shadow casters to a lamp's layers.
* Increase from 10 to 18 texture slots for materials, lamps, word.
An extra texture slot shows up once the last slot is used.
* Memory limit for undo, not enabled by default yet because it
needs the .B.blend to be changed.
* Multiple undo for image painting.
* An offset for dupligroups, so not all objects in a group have to
be at the origin.
HELP BUILD SYSTEM MAINTAINERS: Please help with updating all build systems: the newly added files need to be added. Note that the src/SoftBody has been added for future extension of real-time soft bodies.
without this, an incorrect sound path could cause scripts to to fail, making some functionality not work at all.
This also fixes a problem where samples would be loaded multiple times.
Introduction of a new Delay sensor that can be used to
generate positive and negative triggers at precise time,
expressed in number of frames.
The delay parameter defines the length of the initial
OFF period. A positive trigger is generated at the end
of this period. The duration parameter defines the
length of the ON period following the OFF period.
A negative trigger is generated at the end of the ON period.
If duration is 0, the sensor stays ON and there is no
negative trigger.
The sensor runs the OFF-ON cycle once unless the repeat
option is set: the OFF-ON cycle repeats indefinately
(or the OFF cycle if duration is 0).
The new generic SCA_ISensor::reset() Python function
can be used at any time to restart the sensor: the
current cycle is interrupted and no trigger is generated.
* bugfix for BGE python api - SetParent actuator getObject would segfault if the object was not set.
* Added utility function ConvertPythonToGameObject() that can take a GameObject, string or None and set the game object from this since it was being done in a number of places.
* allow setObject(None), since no object is valid for actuators, Python should be able to set this.
* added optional argument for getObject() so it returns the KX_GameObject rather then its name, would prefer this be default but it could break existing games.
* removed macros that were not used much, some misleading.
* removed error string setting calls that overwrote the error set by PyArg_ParseTuple with a less useful one.
* use python macros Py_RETURN_NONE, Py_RETURN_TRUE, Py_RETURN_FALSE
We assign the material name before check the pointer.
Please Benoit check this and also I have a compiler warning
about the second argument in the previous call of
ConvertMaterialIpos, the argument is NULL but the function
need a dword.
With this patch, only sensors that are connected to
active states are actually registered in the logic
manager. Inactive sensors won't take any CPU,
especially the Radar and Near sensors that use a
physical object for the detection: these objects
are removed from the physics engine.
To take advantage of this optimization patch, you
need to define very light idle state when the
objects are inactive: make them transparent, suspend
the physics, keep few sensors active (e,g a message
sensor to wake up), etc.
=======================================
Alpha blending + sorting was revised, to fix bugs and get it
to work more predictable.
* A new per texture face "Sort" setting defines if the face
is alpha sorted or not, instead of abusing the "ZTransp"
setting as it did before.
* Existing files are converted to hopefully match the old
behavior as much as possible with a version patch.
* On new meshes the Sort flag is disabled by the default, to
avoid unexpected and hard to find slowdowns.
* Alpha sorting for faces was incredibly slow. Sorting faces
in a mesh with 600 faces lowered the framerate from 200 to
70 fps in my test.. the sorting there case goes about 15x
faster now, but it is still advised to use Clip Alpha if
possible instead of regular Alpha.
* There still various limitations in the alpha sorting code,
I've added some comments to the code about this.
Some docs at the bottom of the page:
http://www.blender.org/development/current-projects/changes-since-246/realtime-glsl-materials/
Merged some fixes from the apricot branch, most important
change is that tangents are now exactly the same as the rest
of Blender, instead of being computed in the game engine with a
different algorithm.
Also, the subversion was bumped to 1.
The min/max parameters define a minimum/maximum angle
that the object axis can have with the reference
direction without being constrainted. The angle is
expressed in degree and is limited to 0-180 range.
The min/max parameters define a conical free zone
around the reference direction.
If the object axis is outside that free zone, the
actuator will tend to put it back using as a temporary
reference direction the vector that is exactly at
min or max degree of the reference direction
(depending if the axis angle is below the minimum
or above the maximum) and is located in the plane
formed by the axis and the reference direction.
With a low damping value, this is equivalent to
clamping the axis orientation within min/max degree
of the reference direction.
Backward compatibility corresponds to the absence
of free zone: min = max = 0.
Certain actuators hold a pointer to an objects: Property,
SceneCamera, AddObject, Camera, Parent, TractTo. When a
group is duplicated, the actuators that point to objects
within the group will be relinked to point to the
replicated objects and not to the original objects.
This helps to setup self-contained group with a camera
following a character for example.
This feature also works when adding a single object
(and all its children) with the AddObject actuator.
The second part of the patch extends the protection
against object deletion to all the actuators of the above
list (previously, only the TrackTo, AddObject and
Property actuators were protected). In case the target
object of these actuators is deleted, the BGE won't
crash.
Blender duplicates groups in the 3D view at the location of objects having the DUPLIGROUP option set. This feature is now supported in the BGE: the groups will be instantiated as in the 3D view when the scene is converted. This is useful to populate a scene with multiple enemies without having to actually duplicate the objects in the blend file.
Notes: * The BGE applies the same criteria to instantiate the group as Blender to display them: if you see the group in the 3D view, it will be instantiated in the BGE.
* Groups are instantiated as if the object having the DUPLIGROUP option (usually an empty) executed an AddObject actuator on the top objects of the group (objects without parent).
* As a result, only intra-group parent relationship is supported: the BGE will not instantiate objects that have parents outside the group.
* Intra-group logic bricks connections are preserved between the duplicated objects, even between the top objects of the group.
* For best result, the state engine of the objects in the group should be self-contained: logic bricks should only have intra-group connections. Use messages to communicate with state engines outside the group.
* Nested groups are supported: if one or more objects in the group have the DUPLIGROUP option set, the corresponding groups will be instantiated at the corresponding position and orientation.
* Nested groups are instantiated as separate groups, not as one big group.
* Linked groups are supported as well as groups containing objects from the active layers.
* There is a difference in the way Blender displays the groups in the 3D view and how BGE instantiates them: Blender does not take into account the parent relationship in the group and displays the objects as if they were all children of the object having the DUPLIGROUP option. That's correct for the top objects of the group but not for the children. Hence the orientation of the children objects may be different in the BGE.
* An AddGroup actuator will be added in a future release.
When using states, an action like kick or throw can often switch out before finishing playing the action, and there was no way to play from the start frame the second time round. (even setting the actions current frame through python doesn't work work)
=============================
* Clean up and optimizations in skinned/deformed mesh code.
* Compatibility fixes and clean up in the rasterizer.
* Changes related to GLSL shadow buffers which should have no
effect, to keep the code in sync with apricot.
New Add mode for Ipo actuator
=============================
A new Add button, mutually exclusive with Force button, is available in
the Ipo actuator. When selected, it activates the Add mode that consists
in adding the Ipo curve to the current object situation in world
coordinates, or parent coordinates if the object has a parent. Scale Ipo
curves are multiplied instead of added to the object current scale.
If the local flag is selected, the Ipo curve is added (multiplied) in
the object's local coordinates.
Delta Ipo curves are handled identically to normal Ipo curve and there
is no need to work with Delta Ipo curves provided that you make sure
that the Ipo curve starts from origin. Origin means location 0 for
Location Ipo curve, rotation 0 for Rotation Ipo curve and scale 1 for
Scale Ipo curve.
The "current object situation" means the object's location, rotation
and scale at the start of the Ipo curve. For Loop Stop and Loop End Ipo
actuators, this means at the start of each loop. This initial state is
used as a base during the execution of the Ipo Curve but when the Ipo
curve is restarted (later or immediately in case of Loop mode), the
object current situation at that time is used as the new base.
For reference, here is the exact operation of the Add mode for each
type of Ipo curve (oLoc, oRot, oScale, oMat: object's loc/rot/scale
and orientation matrix at the start of the curve; iLoc, iRot, iScale,
iMat: Ipo curve loc/rot/scale and orientation matrix resulting from
the rotation).
Location
Local=false: newLoc = oLoc+iLoc
Local=true : newLoc = oLoc+oScale*(oMat*iLoc)
Rotation
Local=false: newMat = iMat*oMat
Local=true : newMat = oMat*iMat
Scale
Local=false: newScale = oScale*iScale
Local=true : newScale = oScale*iScale
Add+Local mode is very useful to have dynamic object executing complex
movement relative to their current location/orientation. Of cource,
dynamics should be disabled during the execution of the curve.
Several corrections in state system
===================================
- Object initial state is taken into account when adding object
dynamically
- Fix bug with link count when adding object dynamically
- Fix false on-off detection for Actuator sensor when actuator is
trigged on negative event.
- Fix Parent actuator false activation on negative event
- Loop Ipo curve not restarting at correct frame when start frame is
different from one.
General
=======
- Removal of Damp option in motion actuator (replaced by
Servo control motion).
- No PyDoc at present, will be added soon.
Generalization of the Lvl option
================================
A sensor with the Lvl option selected will always produce an
event at the start of the game or when entering a state or at
object creation. The event will be positive or negative
depending of the sensor condition. A negative pulse makes
sense when used with a NAND controller: it will be converted
into an actuator activation.
Servo control motion
====================
A new variant of the motion actuator allows to control speed
with force. The control if of type "PID" (Propotional, Integral,
Derivate): the force is automatically adapted to achieve the
target speed. All the parameters of the servo controller are
configurable. The result is a great variety of motion style:
anysotropic friction, flying, sliding, pseudo Dloc...
This actuator should be used in preference to Dloc and LinV
as it produces more fluid movements and avoids the collision
problem with Dloc.
LinV : target speed as (X,Y,Z) vector in local or world
coordinates (mostly useful in local coordinates).
Limit: the force can be limited along each axis (in the same
coordinates of LinV). No limitation means that the force
will grow as large as necessary to achieve the target
speed along that axis. Set a max value to limit the
accelaration along an axis (slow start) and set a min
value (negative) to limit the brake force.
P: Proportional coefficient of servo controller, don't set
directly unless you know what you're doing.
I: Integral coefficient of servo controller. Use low value
(<0.1) for slow reaction (sliding), high values (>0.5)
for hard control. The P coefficient will be automatically
set to 60 times the I coefficient (a reasonable value).
D: Derivate coefficient. Leave to 0 unless you know what
you're doing. High values create instability.
Notes: - This actuator works perfectly in zero friction
environment: the PID controller will simulate friction
by applying force as needed.
- This actuator is compatible with simple Drot motion
actuator but not with LinV and Dloc motion.
- (0,0,0) is a valid target speed.
- All parameters are accessible through Python.
Distance constraint actuator
============================
A new variant of the constraint actuator allows to set the
distance and orientation relative to a surface. The controller
uses a ray to detect the surface (or any object) and adapt the
distance and orientation parallel to the surface.
Damp: Time constant (in nb of frames) of distance and
orientation control.
Dist: Select to enable distance control and set target
distance. The object will be position at the given
distance of surface along the ray direction.
Direction: chose a local axis as the ray direction.
Range: length of ray. Objecgt within this distance will be
detected.
N : Select to enable orientation control. The actuator will
change the orientation and the location of the object
so that it is parallel to the surface at the vertical
of the point of contact of the ray.
M/P : Select to enable material detection. Default is property
detection.
Property/Material: name of property/material that the target of
ray must have to be detected. If not set, property/
material filter is disabled and any collisioning object
within range will be detected.
PER : Select to enable persistent operation. Normally the
actuator disables itself automatically if the ray does
not reach a valid target.
time : Maximum activation time of actuator.
0 : unlimited.
>0: number of frames before automatic deactivation.
rotDamp: Time constant (in nb of frame) of orientation control.
0 : use Damp parameter.
>0: use a different time constant for orientation.
Notes: - If neither N nor Dist options are set, the actuator
does not change the position and orientation of the
object; it works as a ray sensor.
- The ray has no "X-ray" capability: if the first object
hit does not have the required property/material, it
returns no hit and the actuator disables itself unless
PER option is enabled.
- This actuator changes the position and orientation but
not the speed of the object. This has an important
implication in a gravity environment: the gravity will
cause the speed to increase although the object seems
to stay still (it is repositioned at each frame).
The gravity must be compensated in one way or another.
the new servo control motion actuator is the simplest
way: set the target speed along the ray axis to 0
and the servo control will automatically compensate
the gravity.
- This actuator changes the orientation of the object
and will conflict with Drot motion unless it is
placed BEFORE the Drot motion actuator (the order of
actuator is important)
- All parameters are accessible through Python.
Orientation constraint
======================
A new variant of the constraint actuator allows to align an
object axis along a global direction.
Damp : Time constant (in nb of frames) of orientation control.
X,Y,Z: Global coordinates of reference direction.
time : Maximum activation time of actuator.
0 : unlimited.
>0: number of frames before automatic deactivation.
Notes: - (X,Y,Z) = (0,0,0) is not a valid direction
- This actuator changes the orientation of the object
and will conflict with Drot motion unless it is placed
BEFORE the Drot motion actuator (the order of
actuator is important).
- This actuator doesn't change the location and speed.
It is compatible with gravity.
- All parameters are accessible through Python.
Actuator sensor
===============
This sensor detects the activation and deactivation of actuators
of the same object. The sensor generates a positive pulse when
the corresponding sensor is activated and a negative pulse when
it is deactivated (the contrary if the Inv option is selected).
This is mostly useful to chain actions and to detect the loss of
contact of the distance motion actuator.
Notes: - Actuators are disabled at the start of the game; if you
want to detect the On-Off transition of an actuator
after it has been activated at least once, unselect the
Lvl and Inv options and use a NAND controller.
- Some actuators deactivates themselves immediately after
being activated. The sensor detects this situation as
an On-Off transition.
- The actuator name can be set through Python.
This meant an error in a script could be reported in a different line or script file which makes it quite hard to trace the problem. There were also places where invalid pointers could be used because of this.
The whole game engine pyapi probably needs to have these checks added.
* Action FrameProp was checking if the string was true, not that it contained any text.
* Added GameObject.getVisible() since there is already a getVisible
* Added GameObject.getPropertyNames() Needed in apricot so Franky can collect and throw items in the level without having the names defined elsewhere or modifying his game logic which is stored in a separate blend file.
To take advantage of this feature, you must have a mesh with
relative shape keys and shape Ipo curves with drivers referring
to bones of the mesh's parent armature.
The BGE will automatically detect the dependency between the
shape keys and the armature and execute the Ipo drivers during
the rendering of the armature actions.
This technique is used to make the armature action more natural:
the shape keys compensate in places where the armature deformation
is uggly and the drivers make sure that the shape correction
is synchronized with the bone position.
Note: This is not compatible with shape actions; BLender does
not allow to have Shape Ipo Curves and Shape actions at the same
time.
This patch introduces two options for the motion actuator:
damping: number of frames to reach the target velocity. It takes
into account the startup velocityin the target velocity direction
and add 1/damping fraction of target velocity until the full
velocity is reached. Works only with linear and angular velocity.
It will be extended to delta and force motion method in a future
release.
clamping: apply the force and torque as long as the target velocity
is not reached. If this option is set, the velocity specified
in linV or angV are not applied to the object but used as target
velocity. You should also specify a force in force or torque field:
the force will be applied as long as the velocity along the axis of
the vector set in linV or angV is not reached. Works best in low
friction environment.
NAND controller is an inverted AND controller: the output is
1 if any of the input is 0.
NOR controller is an inverted OR controller: the output is 0
if any of the input is 1.
XOR controller is an exclusive OR: the output is 1 if and only
if one input is 1 and all the other inputs are 0.
XNOR controller is an inverted XOR: the output is 0 if and only
if one input is 0 and all the other inputs are 0.
The NAND, NORT and XNOR controllers are very usefull to create
complementary outputs to start and stop actuators synchronously.
MSCV project files updated.
Level option is now available on all sensors but is only implemented on
mouse and keyboard sensors. The purpose of that option is to make
the sensor react on level rather than edge by default. It's only
applicable to state engine system when there is a state transition:
the sensor will generate a pulse if the condition is met from the
start of the state. Normally, the keyboard sensor generate a pulse
only when the key is pressed and not when the key is already pressed.
This patch allows to select this behavior.
The second part of the patch corrects the reset method for sensors
with inverted output.
This patch introduces a simple state engine system with the logic bricks. This system features full
backward compatibility, multiple active states, multiple state transitions, automatic disabling of
sensor and actuators, full GUI support and selective display of sensors and actuators.
Note: Python API is available but not documented yet. It will be added asap.
State internals
===============
The state system is object based. The current state mask is stored in the object as a 32 bit value;
each bit set in the mask is an active state. The controllers have a state mask too but only one bit
can be set: a controller belongs to a single state. The game engine will only execute controllers
that belong to active states. Sensors and actuators don't have a state mask but are effectively
attached to states via their links to the controllers. Sensors and actuators can be connected to more
than one state. When a controller becomes inactive because of a state change, its links to sensors
and actuators are temporarily broken (until the state becomes active again). If an actuator gets isolated,
i.e all the links to controllers are broken, it is automatically disabled. If a sensor gets isolated,
the game engine will stop calling it to save CPU. It will also reset the sensor internal state so that
it can react as if the game just started when it gets reconnected to an active controller. For example,
an Always sensor in no pulse mode that is connected to a single state (i.e connected to one or more
controllers of a single state) will generate a pulse each time the state becomes active. This feature is
not available on all sensors, see the notes below.
GUI
===
This system system is fully configurable through the GUI: the object state mask is visible under the
object bar in the controller's colum as an array of buttons just like the 3D view layer mask.
Click on a state bit to only display the controllers of that state. You can select more than one state
with SHIFT-click. The All button sets all the bits so that you can see all the controllers of the object.
The Ini button sets the state mask back to the object default state. You can change the default state
of object by first selecting the desired state mask and storing using the menu under the State button.
If you define a default state mask, it will be loaded into the object state make when you load the blend
file or when you run the game under the blenderplayer. However, when you run the game under Blender,
the current selected state mask will be used as the startup state for the object. This allows you to test
specific state during the game design.
The controller display the state they belong to with a new button in the controller header. When you add
a new controller, it is added by default in the lowest enabled state. You can change the controller state
by clicking on the button and selecting another state. If more than one state is enabled in the object
state mask, controllers are grouped by state for more readibility.
The new Sta button in the sensor and actuator column header allows you to display only the sensors and
actuators that are linked to visible controllers.
A new state actuator is available to modify the state during the game. It defines a bit mask and
the operation to apply on the current object state mask:
Cpy: the bit mask is copied to the object state mask.
Add: the bits that set in the bit mask will be turned on in the object state mask.
Sub: the bits that set in the bit mask will be turned off in the object state mask.
Inv: the bits that set in the bit mask will be inverted in the objecyy state mask.
Notes
=====
- Although states have no name, a simply convention consists in using the name of the first controller
of the state as the state name. The GUI will support that convention by displaying as a hint the name
of the first controller of the state when you move the mouse over a state bit of the object state mask
or of the state actuator bit mask.
- Each object has a state mask and each object can have a state engine but if several objects are
part of a logical group, it is recommended to put the state engine only in the main object and to
link the controllers of that object to the sensors and actuators of the different objects.
- When loading an old blend file, the state mask of all objects and controllers are initialized to 1
so that all the controllers belong to this single state. This ensures backward compatibility with
existing game.
- When the state actuator is activated at the same time as other actuators, these actuators are
guaranteed to execute before being eventually disabled due to the state change. This is useful for
example to send a message or update a property at the time of changing the state.
- Sensors that depend on underlying resource won't reset fully when they are isolated. By the time they
are acticated again, they will behave as follow:
* keyboard sensor: keys already pressed won't be detected. The keyboard sensor is only sensitive
to new key press.
* collision sensor: objects already colliding won't be detected. Only new collisions are
detected.
* near and radar sensor: same as collision sensor.
Shape Action are now supported in the BGE. A new type of actuator "Shape Action" is available on mesh objects. It can be combined with Action actuator on parent armature. Only relative keys are supported. All the usual action options are available: type, blending, priority, Python API. Only actions with shape channels should be specified of course, otherwise the actuator has no effect. Shape action will still work after a mesh replacement provided that the new mesh has compatible shape keys.
GLEW
====
Added the GLEW opengl extension library into extern/, always compiled
into Blender now. This is much nicer than doing this kind of extension
management manually, and will be used in the game engine, for GLSL, and
other opengl extensions.
* According to the GLEW website it works on Windows, Linux, Mac OS X,
FreeBSD, Irix, and Solaris. There might still be platform specific
issues due to this commit, so let me know and I'll look into it.
* This means also that all extensions will now always be compiled in,
regardless of the glext.h on the platform where compilation happens.
Game Engine
===========
Refactoring of the use of opengl extensions and other drawing code
in the game engine, and cleaning up some hacks related to GLSL
integration. These changes will be merged into trunk too after this.
The game engine graphics demos & apricot level survived my tests,
but this could use some good testing of course.
For users: please test with the options "Generate Display Lists" and
"Vertex Arrays" enabled, these should be the fastest and are supposed
to be "unreliable", but if that's the case that's probably due to bugs
that can be fixed.
* The game engine now also uses GLEW for extensions, replacing the
custom opengl extensions code that was there. Removes a lot of
#ifdef's, but the runtime checks stay of course.
* Removed the WITHOUT_GLEXT environment variable. This was added to
work around a specific bug and only disabled multitexturing anyway.
It might also have caused a slowdown since it was retrieving the
environment variable for every vertex in immediate mode (bug #13680).
* Refactored the code to allow drawing skinned meshes with vertex
arrays too, removing some specific immediate mode drawing functions
for this that only did extra normal calculation. Now it always splits
vertices of flat faces instead.
* Refactored normal recalculation with some minor optimizations,
required for the above change.
* Removed some outdated code behind the __NLA_OLDDEFORM #ifdef.
* Fixed various bugs in setting of multitexture coordinates and vertex
attributes for vertex arrays. These were not being enabled/disabled
correct according to the opengl spec, leading to crashes. Also tangent
attributes used an immediate mode call for vertex arrays, which can't
work.
* Fixed use of uninitialized variable in RAS_TexVert.
* Exporting skinned meshes was doing O(n^2) lookups for vertices and
deform weights, now uses same trick as regular meshes.
The best rules for stereo rendering are now applied to Blender. Here is the new situation:
1) The focal distance is now settable through the GUI: select the camera (each camera can have a different setting) and go to the camera data (F9): the "Dof Dist" and "Dof Ob" can be used to set the focal distance for that camera. The "Dof Ob" is interesting because it sets the focal distance so that the center this object will appear at the surface of the screen when running the game.
2) The eye separation is automatically set to focal_distance/30, which is considered to be a reasonable value. If you need a different value, you can always use Python scripting.
Notes:
- If you switch camera during the game, the focal distance will also change unless you have set the focal distance by scripting, in which case it overwrites the focal distance setting of all cameras.
- If you don't set the focal distance in the camera data or by scripting, the default value will be used. The default value corresponds more of less to the near clipping plane which means that all the objects will be very far with little 3D effect.
- If you don't set the eye separation by scripting, it is automatically computed as focal_distance/30, regardless on how the focal distance was set.
The current layer information is now stored in KX_GameObject and inherited from the parent object when dynamically added. This information is used during the rendering the select the lamps. As the selected lamps are always coming from active layers, their position and orientation are correct.
This bug fix is made of two parts:
1) It's now possible to dynamically add a camera.
2) Empty camera name on a SetCamera actuator now points to the actuator's parent object if this object is a camera.
This trick is useful to make current a dynamically created camera: just add a SetCamera actuator on the camera itself and leave the name empty. Later, when the camera is added in the scene with an AddObject actuator, either directly or via a parent object, you just need to activate the actuator to make the newly created camera current. If you set a name on a SetCamera actuator, it will always point to the original camera, even after replication.
This patch consists in new KX_GameObject::SetParent() and KX_GameObject::RemoveParent() functions to create and destroy parent relation during game. These functions are accessible through python and through a new actuator KX_ParentActuator. Function documentation in PyDoc.
The object keeps its orientation, position and scale when it is parented but will further rotate, move and scale with its parent from that point on. When the parent relation is broken, the object keeps the orientation, position and scale it had at that time.
The function has no effect if any of the X/Y/Z scale of the object or its new parent are below Epsilon.
Changing the mesh of an object that has a deform controller (armature) is now properly handled. The new mesh must have vertex groups matching the armature bones. In simple terms, the new mesh must deform correctly when you assign it to the object in Blender and you test the action. It will deform the same when you replace the object mesh during the game.
This patch modifies the BL_ConvertMesh method from the data conversion module in order to reduce the number of polygon
material objects that are created.
Normally, there should be only one material object for each material bucket(the group of meshes that are rendered together
with a single material). However, the number of materials that are created right now in the converter is much higher
and eats a lot of memory in scenes with large polygon counts. This patch deletes those material objects(KX_BlenderMaterial)
that are used only temporarily in the converter(and are now deleted only when the converter is destroyed, at the end
of the game).
For a cube that's subdivided 7 times(90+ k polygons) I get 200 MB usage in the game engine in 2.45 and 44 MB with a
svn build with this patch applied if the "Use Blender Materials" option is activated in the Game menu.
- check that an object has been created before setting the physics environment
- check that there is an active camera before using it
- when a camera is deleted, remove it from m_cameras list
rayCastTo(other,dist,prop)
Look towards another point/KX_GameObject and return first object hit within dist with a property that match prop, None if no object found or if it does not match prop.
Parameters:
other = 3-tuple (xyz coordinates) or object reference (target=center of object)
(type = list [x,y,z] or object reference)
dist = max distance of detection (can be negative => look behind)
If 0 or omitted => detect up to other
(type=float)
prop = property name that object must have
If empty or omitted => detect any object
(type=string)
1. All Ipo channels are now independent.
In Blender 2.45, all 3 Loc Ipo channels were automatically set
together. For example, having just a LocX Ipo channel was sufficient
to fix the X, Y and Z coordinates, with the Y and Z value taken
from the object original Y and Z location in Blender. The same
was true for the 3 Rot and the 3 Scale Ipo channels: the missing
channels were assumed to have constant value taken from the object
original orientation/scale in Blender.
With this patch, all Ipo channels are now independent.
THIS WILL CREATE BACKWARD COMPATIBILITY PROBLEM if you omit to
define the 3 channels of a same type together in your Blend file:
the undefined Loc, Rot, Scale coordinates of the object will
be influenced by the parent/spawner Loc/Rot/Scale in case the
object is a child or dynamically created.
2. Delta Loc, Rot, Scale are now supported with the following
limitations:
- The delta Loc/Rot Ipo modify the object global (NOT local)
location/orientation
- The delta Scale change the object local scale
- The delta Ipo curves are relative to the object starting
Loc/Rot/Scale when the Ipo was first activated; after that, the
delta Ipo becomes global. This means that the object will return
to this initial Loc/Rot/Scale when you later restart the Ipo
curve, even if you had changed the object Loc/Rot/Scale in the
meantime. Of course this applies only to the specific Loc/Rot/Scale
coordinate that are defined in the Ipo channels as the channels
are now independent.
3. When the objects are converted from Blender to the BGE, the
delta Loc/Rot/Scale that might result from initial non-zero values
in delta Ipo Curves will be ignored. However, as soon as the
delta Ipo curve is activated, the non-zero values will be taken
into account and the object will jump to the same Loc/Rot/Scale
situation as in Blender. Note that delta Ipo curves with initial
non-zero values is bad practice; logically, a delta Ipo curver
should always start from 0.
4. If you define both a global and delta channel of the same
type (LocX and DLocX), the result will be a global channel equivalent
to the sum of the two channels (LocX+DLocX).
This adds fractional FPS support to blender and should finally
make NTSC work correctly.
NTSC has an FPS of 30.0/1.001 which is approximately 29.97 FPS.
Therefore, it is not enough to simply make frs_sec a float, since
you can't represent this accurately enough.
I added a seperate variable frs_sec_base and FPS is now
frs_sec / frs_sec_base.
I changed all the places, where frs_sec was used to my best knowledge.
For convenience sake, I added several macros, that should make life
easier in the future:
FRA2TIME(a) : convert frame number to a double precision time in seconds
TIME2FRA(a) : the same in the opposite direction
FPS : return current FPS as a double precision number
(last resort)
This closes bug #6715
Standard framerates not supported / breaks sync -- 23.967 29.967 etc.
https://projects.blender.org/tracker/?func=detail&aid=6715&group_id=9&atid=125
Please give this heavy testing with NTSC files, quicktime in/export
and the python interface.
Errors are most probably only spotted on longer timelines, so that is
also important.
The patch was tested by Troy Sobotka and me, so it most probably should
work out of the box, but wider testing is important, since errors are
very subtle.
Enjoy!
using mface->flag for both.
Also found that the cdDM_drawMappedFaces and cdDM_drawFacesTex_common could get normals mixed up when rendering hidden faces. because hidden/invisible faces used continue without advancing to the next normal.