trusty (3) SoGLRenderAction.3.gz

Provided by: libcoin80-doc_3.1.4~abc9f50-4ubuntu2_all bug

NAME

       SoGLRenderAction -

       The SoGLRenderAction class renders the scene graph with OpenGL calls.

       Applying this method at a root node for a scene graph, path or pathlist will render all geometry
       contained within that instance to the current OpenGL context.

SYNOPSIS

       #include <Inventor/actions/SoGLRenderAction.h>

       Inherits SoAction.

       Inherited by SoBoxHighlightRenderAction, and SoLineHighlightRenderAction.

   Public Types
       enum TransparencyType { SCREEN_DOOR, ADD, DELAYED_ADD, SORTED_OBJECT_ADD, BLEND, DELAYED_BLEND,
           SORTED_OBJECT_BLEND, SORTED_OBJECT_SORTED_TRIANGLE_ADD, SORTED_OBJECT_SORTED_TRIANGLE_BLEND, NONE,
           SORTED_LAYERS_BLEND }
       enum TransparentDelayedObjectRenderType { ONE_PASS, NONSOLID_SEPARATE_BACKFACE_PASS }
       enum AbortCode { CONTINUE, ABORT, PRUNE, DELAY }
       enum SortedObjectOrderStrategy { BBOX_CENTER, BBOX_CLOSEST_CORNER, BBOX_FARTHEST_CORNER, CUSTOM_CALLBACK
           }
       typedef AbortCode SoGLRenderAbortCB (void *userdata)

   Public Member Functions
       virtual SoType getTypeId (void) const
       SoGLRenderAction (const SbViewportRegion &viewportregion)
       virtual ~SoGLRenderAction (void)
       void setViewportRegion (const SbViewportRegion &newregion)
       const SbViewportRegion & getViewportRegion (void) const
       void setUpdateArea (const SbVec2f &origin, const SbVec2f &size)
       void getUpdateArea (SbVec2f &origin, SbVec2f &size) const
       void setAbortCallback (SoGLRenderAbortCB *const func, void *const userdata)
       void getAbortCallback (SoGLRenderAbortCB *&func_out, void *&userdata_out) const
       void setTransparencyType (const TransparencyType type)
       TransparencyType getTransparencyType (void) const
       void setTransparentDelayedObjectRenderType (TransparentDelayedObjectRenderType type)
       TransparentDelayedObjectRenderType getTransparentDelayedObjectRenderType (void) const
       void setSmoothing (const SbBool smooth)
       SbBool isSmoothing (void) const
       void setNumPasses (const int num)
       int getNumPasses (void) const
       void setPassUpdate (const SbBool flag)
       SbBool isPassUpdate (void) const
       void setPassCallback (SoGLRenderPassCB *const func, void *const userdata)
       void setCacheContext (const uint32_t context)
       uint32_t getCacheContext (void) const
       void addDelayedPath (SoPath *path)
       SbBool isRenderingDelayedPaths (void) const
       SbBool handleTransparency (SbBool istransparent=FALSE)
       void setCurPass (const int passnum, const int numpasses)
       int getCurPass (void) const
       SbBool abortNow (void)
       void setRenderingIsRemote (SbBool isremote)
       SbBool getRenderingIsRemote (void) const
       virtual void invalidateState (void)
       void addPreRenderCallback (SoGLPreRenderCB *func, void *userdata)
       void removePreRenderCallback (SoGLPreRenderCB *func, void *userdata)
       void setSortedLayersNumPasses (int num)
       int getSortedLayersNumPasses (void) const
       void setSortedObjectOrderStrategy (const SortedObjectOrderStrategy strategy, SoGLSortedObjectOrderCB
           *cb=NULL, void *closure=NULL)
       void setDelayedObjDepthWrite (SbBool write)
       SbBool getDelayedObjDepthWrite (void) const
       SbBool isRenderingTranspPaths (void) const
       SbBool isRenderingTranspBackfaces (void) const

   Static Public Member Functions
       static SoType getClassTypeId (void)
       static void addMethod (const SoType type, SoActionMethod method)
       static void enableElement (const SoType type, const int stackindex)
       static void initClass (void)

   Protected Member Functions
       virtual const
           SoEnabledElementsList & getEnabledElements (void) const "
       virtual void beginTraversal (SoNode *node)
       virtual void endTraversal (SoNode *node)

   Static Protected Member Functions
       static SoEnabledElementsList * getClassEnabledElements (void)
       static SoActionMethodList * getClassActionMethods (void)

   Additional Inherited Members

Detailed Description

       The SoGLRenderAction class renders the scene graph with OpenGL calls.

       Applying this method at a root node for a scene graph, path or pathlist will render all geometry
       contained within that instance to the current OpenGL context.

Member Typedef Documentation

   typedef SoGLRenderAction::SoGLRenderAbortCB
       Abort callbacks should be of this type.

       See Also:
           setAbortCallback()

Member Enumeration Documentation

   enum SoGLRenderAction::TransparencyType
       Various settings for how to do rendering of transparent objects in the scene. Some of the settings will
       provide faster rendering, while others give you better quality rendering.

       Note that doing correct rendering of multiple transparent objects often fails, because to be 100%
       correct, all polygons needs to be rendered in sorted order, and polygons can't intersect each other. In a
       dynamic scene graph it is often impossible to guarantee that no polygons intersect, and finding an
       algorithm that does correct sorting of polygons for all possible cases is very hard and time-consuming.

       The highest quality transparency mode in the original SGI / TGS Open Inventor is
       SoGLRenderAction::SORTED_OBJECT_BLEND, where all transparent objects are rendered in sorted order in a
       rendering pass after all opaque objects. However, this mode does not sort the polygons, and if you have
       an object where some polygon A is behind some other polygon B, the transparency will only be correct if A
       happens to be rendered before B. For other camera angles, where B is behind A, the transparency will not
       be correct.

       In Coin we have a new transparency mode that solves some of these problems:
       SoGLRenderAction::SORTED_OBJECT_SORTED_TRIANGLE_BLEND. In addition to sorting the objects, all polygons
       inside each object is also sorted back-to-front when rendering. But, if you have intersecting objects
       and/or intersecting polygons, even this transparency mode will fail. Also, because of the polygon
       sorting, this transparency mode is quite slow. It is possible to speed things up using the
       SoTransparencyType node, though, which enables you to set different transparency modes for different
       parts of the scene graph. If you have only have a few objects where you need to sort the polygons, you
       can use SoGLRenderAction::SORTED_OBJECT_SORTED_TRIANGLE_BLEND for those, and for instance
       SoGLRenderAction::SORTED_OBJECT_BLEND for all other transparent objects.

       The highest quality transparency mode in Coin is SoGLRenderAction::SORTED_LAYERS_BLEND. It is also the
       only mode that overrides all other modes in the scenegraph.

       (One important note about this mode: we've had reports from users that some OpenGL drivers -- possibly
       particular for some Mac OS X systems -- significantly degrades rendering performance. So be careful and
       test your application on a wide variety of run-time systems when using
       SoGLRenderAction::SORTED_LAYERS_BLEND.)

       See Also:
           SoTransparencyType

       Enumerator

       SCREEN_DOOR
              Transparent triangles are rendered with a dither pattern. This is a fast (on most GFX cards) but
              not-so-high-quality transparency mode.

       One particular feature of this mode is that you are guaranteed that it always renders the transparent
       parts of the scene correct with regard to internal depth ordering of objects / polygons, something which
       is not the case for any other transparency mode.

       Polygons rendered with only transparent textures are not shown as being transparent when using this mode.
       The reason being that the SCREEN_DOOR mode is working on polygons, not pixels. To render polygons with
       dither pattern, a material node has to be inserted into the scenegraph with it's transparency field set.

       ADD    Transparent objects are rendered using additive alpha blending. Additive blending is probably
              mostly used to create special transparency effects. The new pixel color is calculated as the
              current pixel color plus the source pixel color multiplied with the source pixel alpha value.

       DELAYED_ADD
              SoGLRenderAction::DELAYED_ADD Transparent objects are rendered using additive alpha blending, in a
              second rendering pass with depth buffer updates disabled.

       SORTED_OBJECT_ADD
              Transparent objects are rendered using additive alpha blending. Opaque objects are rendered first,
              and transparent objects are rendered back to front with z-buffer updates disabled.

       BLEND  Transparent objects are rendered using multiplicative alpha blending.

       Multiplicative alpha blending is the blending type that is most often used to render transparent objects.
       The new pixel value is calculated as the old pixel color multiplied with one minus the source alpha
       value, plus the source pixel color multiplied with the source alpha value.

       We recommend that you use this transparency mode if you have only one transparent object in your scene,
       and you know that it will be rendered after the opaque objects.

       DELAYED_BLEND
              Transparent objects are rendered using multiplicative alpha blending, in a second rendering pass
              with depth buffer updates disabled.

       Use this transparency type when you have one transparent object, or several transparent object that you
       know will never overlap (when projected to screen). Since the transparent objects are rendered after
       opaque ones, you'll not have to worry about putting the transparent objects at the end of your scene
       graph. It will not be as fast as the BLEND transparency type, of course, since the scene graph is
       traversed twice.

       SORTED_OBJECT_BLEND
              Transparent objects are rendered using multiplicative alpha blending, Opaque objects are rendered
              first, and transparent objects are rendered back to front with z-buffer updates disabled.

       Use this transparency mode when you have several transparent object that you know might overlap (when
       projected to screen). This method will require 1 + num_transparent_objects rendering passes. Path
       traversal is used when rendering transparent objects, of course, but it might still be slow if you have
       lots of state changes before your transparent object. When using this mode, we recommend placing the
       transparent objects as early as possible in the scene graph to minimize traversal overhead.

       SORTED_OBJECT_SORTED_TRIANGLE_ADD
              This transparency type is a Coin extension versus the original SGI Open Inventor API.

       Transparent objects are rendered back to front, and triangles in each object are sorted back to front
       before rendering.

       See description for SORTED_OBJECT_SORTED_TRIANGLE_BLEND for more information about this transparency
       type.

       SORTED_OBJECT_SORTED_TRIANGLE_BLEND
              This transparency type is a Coin extension versus the original SGI Open Inventor API.

       Transparent objects are rendered back to front, and triangles in each object are sorted back to front
       before rendering.

       Use this transparency type when you have one (or more) transparent object(s) where you know triangles
       might overlap inside the object. This transparency type might be very slow if you have an object with
       lots of triangles, since all triangles have to be sorted before rendering, and an unoptimized rendering
       loop is used when rendering. Lines and points are not sorted before rendering. They are rendered as in
       the normal SORTED_OBJECT_BLEND transparency type.

       Please note that this transparency mode does not guarantee 'correct' transparency rendering. It is almost
       impossible to find an algorithm that will sort triangles correctly in all cases, and intersecting
       triangles are not handled. Also, since each object is handled separately, two intersecting object will
       lead to incorrect transparency.

       NONE   This transparency type is a Coin extension versus the Open Inventor API.

       Turns off transparency for objects, even if transparency is set using an SoMaterial node.

       Since:
           Coin 1.0

       SORTED_LAYERS_BLEND
              This transparency type is a Coin extension versus the original SGI Open Inventor API.

       By using this transparency type, the SoGLRenderAction will render normal and intersecting transparent
       objects correctly independent of rendering order. It is the only transparency type rendering mode which
       is guaranteed to do so.

       This mode is different from all other modes in that it overrides the SoTransparencyType nodes in the
       scenegraph; all objects are drawn using SORTED_LAYERS_BLEND.

       There are currently two separate code paths for this mode. Both paths are heavily based on OpenGL
       extensions. The first method is based on extensions which are only available on NVIDIA chipsets (GeForce3
       and above, except GeForce4 MX). These extensions are GL_NV_texture_shader, GL_NV_texture_rectangle or
       GL_EXT_texture_rectangle, GL_NV_register_combiners, GL_ARB_shadow and GL_ARB_depth_texture. Please note
       that this transparency type occupy all four texture units on the NVIDIA card for all the rendering
       passes, except the first. Textured surfaces will therefore only be textured if they are not occluded by
       another transparent surface.

       The second method utilise the GL_ARB_fragment_program extension. This extension is currently supported by
       the GeForceFX family and the Radeon 9500 and above. This technique is faster than the pure NVIDIA method.
       The fragment program method will automatically be chosen if possible. Please note that one should beware
       not to place the near-plane too close to the camera due to the lack of floating point precision control
       in fragment programs. Doing so may lead to loss of precision around the edges and 'jaggedness' of the
       transparent geometry.

       Setting the environment variable COIN_SORTED_LAYERS_USE_NVIDIA_RC to '1' will force the use of former
       code path instead of the latter, even if it is available.

       A rendering context with >= 24 bits depth buffer and 8 bits alpha channel must be the current rendering
       context for this blending mode to actually become activated. If the current rendering canvas does not
       have these properties, Coin will fall back on a simpler transparency handling mode. If you are using one
       of the window-system binding libraries provided by Kongsberg Oil & Gas Technologies, e.g. SoXt, SoQt or
       SoWin, you will need to explicitly enable this in your viewer. See the API documentation of the
       setAlphaChannel() method of either SoXtGLWidget, SoQtGLWidget or SoWinGLWidget.

       The detection of whether or not the SORTED_LAYERS_BLEND mode can be used will be done automatically by
       the Coin internals. If one or more of the necessary conditions listed above are unavailable,
       SoGLRenderAction::SORTED_OBJECT_BLEND will be used as the transparency type instead.

       To be able to render correct transparency independent of object order, one have to render in multiple
       passes. This technique is based on depth-peeling which strips away depth layers with each successive
       pass. The number of passes is therefore an indication of how deep into the scene transparent surfaces
       will be rendered with transparency. A higher number will lead to a lower framerate but higher quality for
       scenes with a lot of transparent surfaces. The default number of passes is '4'. This number can be
       specified using the SoGLRenderAction::setSortedLayersNumPasses() or by letting the environment variable
       COIN_NUM_SORTED_LAYERS_PASSES or OIV_NUM_SORTED_LAYERS_PASSES specify the number of passes.

       A more detailed presentation of the algorithm is written by Cass Everitt at NVIDIA;

       Since:
           Coin 2.2

           TGS Inventor 4.0

   enum SoGLRenderAction::TransparentDelayedObjectRenderType
       Enumerates the render types of transparent objects.

       Enumerator

       ONE_PASS
              Normal one pass rendering. This might cause artifacts for non-solid objects.

       NONSOLID_SEPARATE_BACKFACE_PASS
              Non-solid objects are handled in an extra rendering pass. Backfacing polygons are rendered in the
              first pass, and the front facing in the second pass.

   enum SoGLRenderAction::AbortCode
       The return codes which an SoGLRenderAbortCB callback function should use.

       See Also:
           setAbortCallback()

       Enumerator

       CONTINUE
              Continue rendering as usual.

       ABORT  Abort the rendering action immediately.

       PRUNE  Do not render the current node or any of its children, but continue the rendering traversal.

       DELAY  Delay rendering of the current node (and its children) until the next rendering pass.

   enum SoGLRenderAction::SortedObjectOrderStrategy
       Enumerator

       BBOX_CENTER
              Do the sorting based on the center of the object bounding box.

       See Also:
           setSortedObjectOrderStrategy().

       Since:
           Coin 2.5

       BBOX_FARTHEST_CORNER
              Do the sorting based on the bounding box corner farthest from the camera.

       See Also:
           setSortedObjectOrderStrategy().

       Since:
           Coin 2.5

       CUSTOM_CALLBACK
              Use a custom callback to determine the sorting order.

       See Also:
           setSortedObjectOrderStrategy().

       Since:
           Coin 2.5

Constructor & Destructor Documentation

   SoGLRenderAction::SoGLRenderAction (const SbViewportRegion &viewportregion)
       Constructor. Sets up the render action for rendering within the given viewportregion.

   SoGLRenderAction::~SoGLRenderAction (void) [virtual]
       Destructor.

Member Function Documentation

   SoType SoGLRenderAction::getTypeId (void) const [virtual]
       Returns the type identification of an action derived from a class inheriting SoAction. This is used for
       run-time type checking and 'downward' casting.

       Usage example:

       void bar(SoAction * action)
       {
         if (action->getTypeId() == SoGLRenderAction::getClassTypeId()) {
           // safe downward cast, know the type
           SoGLRenderAction * glrender = (SoGLRenderAction *)action;
         }
         return; // ignore if not renderaction
       }

       For application programmers wanting to extend the library with new actions: this method needs to be
       overridden in all subclasses. This is typically done as part of setting up the full type system for
       extension classes, which is usually accomplished by using the pre-defined macros available through
       Inventor/nodes/SoSubAction.h: SO_ACTION_SOURCE, SO_ACTION_INIT_CLASS and SO_ACTION_CONSTRUCTOR.

       For more information on writing Coin extensions, see the SoAction class documentation.

       Returns the actual type id of an object derived from a class inheriting SoAction. Needs to be overridden
       in all subclasses.

       Implements SoAction.

       Reimplemented in SoBoxHighlightRenderAction, and SoLineHighlightRenderAction.

   void SoGLRenderAction::addMethod (const SoTypetype, SoActionMethodmethod) [static]
       This API member is considered internal to the library, as it is not likely to be of interest to the
       application programmer.

   void SoGLRenderAction::enableElement (const SoTypetype, const intstackindex) [static]
       This API member is considered internal to the library, as it is not likely to be of interest to the
       application programmer.

   const SoEnabledElementsList & SoGLRenderAction::getEnabledElements (void) const [protected],  [virtual]
       Returns a list of the elements used by action instances of this class upon traversal operations.

       Reimplemented from SoAction.

       Reimplemented in SoBoxHighlightRenderAction, and SoLineHighlightRenderAction.

   void SoGLRenderAction::setViewportRegion (const SbViewportRegion &newregion)
       Sets the viewport region for rendering. This will then override the region passed in with the
       constructor.

   const SbViewportRegion & SoGLRenderAction::getViewportRegion (void) const
       Returns the viewport region for the rendering action.

   void SoGLRenderAction::setUpdateArea (const SbVec2f &origin, const SbVec2f &size)
       Sets the area of the OpenGL context canvas we should render into.

       The coordinates for origin and size should be normalized to be within [0.0, 1.0]. The default settings
       are <0.0, 0.0> for the origin and <1.0, 1.0> for the size, using the full size of the rendering canvas.

   void SoGLRenderAction::getUpdateArea (SbVec2f &origin, SbVec2f &size) const
       Returns information about the area of the rendering context window to be updated.

   void SoGLRenderAction::setAbortCallback (SoGLRenderAbortCB *constfunc, void *constuserdata)
       Sets the abort callback. The abort callback is called by the action for each node during traversal to
       check for abort conditions.

       The callback method should return one of the SoGLRenderAction::AbortCode enum values to indicate how the
       action should proceed further.

       Since the client SoGLRenderAbortCB callback function only has a single void* argument for the userdata,
       one has to do some additional work to find out which node the callback was made for. One can do this by
       for instance passing along the action pointer as userdata, and then call the
       SoGLRenderAction::getCurPath() method. The tail of the path will then be the last traversed node. Like
       this:

       // set up so we can abort or otherwise intervene with the render
       // traversal:
       myRenderAction->setAbortCallback(MyRenderCallback, myRenderAction);

       // [...]

       SoGLRenderAction::AbortCode
       MyRenderCallback(void * userdata)
       {
         SoGLRenderAction * action = (SoGLRenderAction *)userdata;
         SoNode * lastnode = action->getCurPath()->getTail();

         // [...]
         return SoGLRenderAction::CONTINUE;
       }

       See Also:
           SoGLRenderAction::AbortCode

   void SoGLRenderAction::getAbortCallback (SoGLRenderAbortCB *&func_out, void *&userdata_out) const
       Returns the abort callback settings.

       See Also:
           setAbortCallback

       Since:
           Coin 3.0

   void SoGLRenderAction::setTransparencyType (const TransparencyTypetype)
       Sets the transparency rendering method for transparent objects in the scene graph.

       See Also:
           SoGLRenderAction::TransparencyType

   SoGLRenderAction::TransparencyType SoGLRenderAction::getTransparencyType (void) const
       Returns the transparency rendering type.

   void SoGLRenderAction::setTransparentDelayedObjectRenderType (TransparentDelayedObjectRenderTypetype)
       Sets the render type of delayed or sorted transparent objects. Default is ONE_PASS.

       Since:
           Coin 3.0

   SoGLRenderAction::TransparentDelayedObjectRenderType SoGLRenderAction::getTransparentDelayedObjectRenderType
       (void) const
       Returns the render type of delayed or sorted transparent objects.

       Since:
           Coin 3.0

   void SoGLRenderAction::setSmoothing (const SbBoolsmooth)
       Sets (or unsets) smoothing. If the smoothing flag is on, Coin will try to use built-in features from the
       OpenGL implementation to smooth the appearance of otherwise jagged line and point primitives, calling

           glEnable(GL_POINT_SMOOTH);
           glEnable(GL_LINE_SMOOTH);

       ...before rendering the scene.

       This is a simple (and computationally non-intensive) way of doing anti-aliasing.

       Default value for this flag is to be off.

   SbBool SoGLRenderAction::isSmoothing (void) const
       Returns whether smoothing is set or not.

   void SoGLRenderAction::setNumPasses (const intnum)
       Sets the number of rendering passes. Default is 1, anything greater will enable antialiasing through the
       use of an OpenGL accumulation buffer.

   int SoGLRenderAction::getNumPasses (void) const
       Returns the number of rendering passes done on updates.

   void SoGLRenderAction::setPassUpdate (const SbBoolflag)
       Sets whether each pass should render to screen or not.

   SbBool SoGLRenderAction::isPassUpdate (void) const
       Returns the value of the 'show intermediate updates' flag.

       See Also:
           setPassUpdate()

   void SoGLRenderAction::setPassCallback (SoGLRenderPassCB *constfunc, void *constuserdata)
       Sets the pass callback. The callback is called between each rendering pass.

   void SoGLRenderAction::setCacheContext (const uint32_tcontext)
       Sets the OpenGL cache context key, which is used for deciding when to share OpenGL display lists.

       Each SoGLRenderAction has a cache context id. This can be set using SoGLRenderAction::setCacheContext().
       The cache context id must be unique, so that different texture objects and display lists are created for
       uncompatible GL contexts. For instance, when SoGLRenderAction traverses an SoTexture2 node, the node
       checks if it has a texture object created for the cache context. If not, a new texture object will be
       created and used when rendering.

       See Also:
           SoGLCacheContextElement::getUniqueCacheContext()

   uint32_t SoGLRenderAction::getCacheContext (void) const
       Returns the cache context key for this rendering action instance.

   void SoGLRenderAction::addDelayedPath (SoPath *path)
       Adds a path to the list of paths to render after the current pass.

   SbBool SoGLRenderAction::isRenderingDelayedPaths (void) const
       Returns a flag indicating whether or not we are currently rendering from the list of delayed paths of the
       scene graph.

   SbBool SoGLRenderAction::handleTransparency (SbBoolistransparent = FALSE)
       Used by shape nodes or others which need to know whether or not they should immediately render themselves
       or if they should wait until the next pass. It also enables/disabled blending based on the istransparent
       parameter.

       If you're using an SoCallback or a non-shape node to render your geometry, you can use this function to
       make sure your node is only rendered once. This function consider the istransparent parameter, and when
       TRUE it will return TRUE on the first pass, and FALSE on the second pass. For non-transparent objects it
       returns FALSE on the first pass, TRUE on the second.

       Please note that this function considers the current transparency type when deciding what to do. It will
       delay rendering only when the transparency type is DELAYED_* or SORTED_OBJECT_*. For other transparency
       types, transparent objects are rendered in the same pass as opaque objects.

   void SoGLRenderAction::setCurPass (const intpassnum, const intnumpasses)
       Sets the current rendering pass to passnum. This can be used when antialiasing is controlled from outside
       the SoGLRenderAction instance. numpasses is the total number of rendering passes to be used.

       Please note that this will disable any antialiasing set using the setNumPasses() method. You can reenable
       the internal antialiasing again by calling setNumPasses()

       Since:
           Coin 3.1

   int SoGLRenderAction::getCurPass (void) const
       Returns the number of the current rendering pass.

   SbBool SoGLRenderAction::abortNow (void)
       Returns TRUE if the render action should abort now based on user callback.

       See Also:
           setAbortCallback()

   void SoGLRenderAction::setRenderingIsRemote (SbBoolisremote)
       Let SoGLRenderAction instance know if application is running on the local machine or if the rendering
       instructions are sent over the network.

       The flag is used to optimize rendering. For instance should the displaylist caching strategy be
       influenced by this flag to be more aggressive with the caching when rendering instructions are passed
       over the network.

       Default value is FALSE. The value of the flag will not be changed internally from the Coin library code,
       as it is meant to be controlled from client code -- typically from the SoQt / SoXt / SoWin / SoGtk
       libraries.

       See Also:
           getRenderingIsRemote()

   SbBool SoGLRenderAction::getRenderingIsRemote (void) const
       Returns whether or not the application is running remotely.

       See Also:
           setRenderingIsRemote()

   void SoGLRenderAction::invalidateState (void) [virtual]
       Invalidates the state, forcing it to be recreated at the next apply() invocation.

       Reimplemented from SoAction.

   void SoGLRenderAction::addPreRenderCallback (SoGLPreRenderCB *func, void *userdata)
       Adds a callback which is invoked right before the scene graph traversal starts. All necessary GL
       initialization is then done (e.g. the viewport is correctly set), and this callback can be useful to, for
       instance, clear the viewport before rendering, or draw a bitmap in the background before rendering etc.

       The callback is only invoked once (before the first rendering pass) when multi pass rendering is enabled.

       Please note that SoSceneManager usually adds a callback to clear the GL buffers in
       SoSceneManager::render(). So, if you plan to for instance draw an image in the color buffer using this
       callback, you should make sure that the scene manager doesn't clear the buffer. This can be done either
       by calling SoSceneManager::render() with both arguments FALSE, or, if you're using one of our GUI
       toolkits (SoXt/SoQt/SoGtk/SoWin), call setClearBeforeRender() on the viewer.

       This method is an extension versus the Open Inventor API.

       See Also:
           removePreRenderCallback().

   void SoGLRenderAction::removePreRenderCallback (SoGLPreRenderCB *func, void *userdata)
       Removed a callback added with the addPreRenderCallback() method.

       This method is an extension versus the Open Inventor API.

       See Also:
           addPreRenderCallback()

   void SoGLRenderAction::setSortedLayersNumPasses (intnum)
       Sets the number of passes to render in SoGLRenderAction::SORTED_LAYERS_BLEND mode. Default number of
       passes is 4. This number can also be adjusted by setting the COIN_NUM_SORTED_LAYERS_PASSES or
       OIV_NUM_SORTED_LAYERS_PASSES environment variable.

   int SoGLRenderAction::getSortedLayersNumPasses (void) const
       Returns the number of passes to render when in SoGLRenderAction::SORTED_LAYERS_BLEND mode.

   void SoGLRenderAction::setSortedObjectOrderStrategy (const SortedObjectOrderStrategystrategy,
       SoGLSortedObjectOrderCB *cb = NULL, void *closure = NULL)
       Sets the strategy used for sorting transparent objects.

       The CUSTOM_CALLBACK strategy enables the user to supply a callback which is called for each transparent
       shape. This strategy can be used if the built in sorting strategies aren't sufficient.

       The callback should return a floating point value to be used when sorting the objects in Coin. This
       floating point value is interpreted as a distance to the camera, and objects with higher values will be
       sorted behind objects with lower values.

       The callback will supply the SoGLRenderAction instance, and the path to the current object can be found
       using SoAction::getCurPath().

       Since:
           Coin 2.5

   void SoGLRenderAction::setDelayedObjDepthWrite (SbBoolwrite)
       Set whether depth buffer updates should be done when rendering delayed or sorted transparent objects.

       Since:
           Coin 3.0

   SbBool SoGLRenderAction::getDelayedObjDepthWrite (void) const
       Return whether depth buffer updates should be done when rendering delayed or sorted transparent objects.
       Default is FALSE.

       Since:
           Coin 3.0

   SbBool SoGLRenderAction::isRenderingTranspPaths (void) const
       Returns TRUE if the action is currently rendering delayed or sorted transparent objects.

       Since:
           Coin 3.0

   SbBool SoGLRenderAction::isRenderingTranspBackfaces (void) const
       Returns TRUE if the action is currently rendering backfacing polygons in NONSOLID_SEPARATE_BACKFACE_PASS
       mode.

       Since:
           Coin 3.0

   void SoGLRenderAction::beginTraversal (SoNode *node) [protected],  [virtual]
       This virtual method is called from SoAction::apply(), and is the entry point for the actual scenegraph
       traversal.

       It can be overridden to initialize the action at traversal start, for specific initializations in the
       action subclasses inheriting SoAction.

       Default method just calls traverse(), which any overridden implementation of the method must do too (or
       call SoAction::beginTraversal()) to trigger the scenegraph traversal.

       Reimplemented from SoAction.

   void SoGLRenderAction::endTraversal (SoNode *node) [protected],  [virtual]
       This virtual method can be overridden to execute code after the scene graph traversal. Default method
       does nothing.

       Reimplemented from SoAction.

Author

       Generated automatically by Doxygen for Coin from the source code.