SoGLRenderAction(3IV)

NAME
SoGLRenderAction — renders a scene graph using OpenGL

INHERITS FROM
SoAction > SoGLRenderAction

SYNOPSIS
#include <Inventor/actions/SoGLRenderAction.h>

typedef AbortCode
SoGLRenderAbortCB(void *userData)
typedef void
SoGLRenderPassCB(void *userData)

enum TransparencyType {
SoGLRenderAction::SCREEN_DOOR
Uses stipple patterns for screen-door transparency
SoGLRenderAction::ADD
Uses additive alpha blending
SoGLRenderAction::DELAYED_ADD
Uses additive blending, rendering all transparent objects after opaque ones
SoGLRenderAction::SORTED_OBJECT_ADD
Same as DELAYED_ADD, but sorts transparent objects by distances of bounding boxes from camera
SoGLRenderAction::BLEND
Uses multiplicative alpha blending
SoGLRenderAction::DELAYED_BLEND
Uses multiplicative alpha blending, rendering all transparent objects after opaque ones
SoGLRenderAction::SORTED_OBJECT_BLEND
Same as DELAYED_BLEND, but sorts transparent objects by distances of bounding boxes from camera
}

enum AbortCode {
SoGLRenderAction::CONTINUE
Continue traversal as usual
SoGLRenderAction::ABORT
Stop traversing the rest of the graph
SoGLRenderAction::PRUNE
Do not traverse this node or its children, but continue
SoGLRenderAction::DELAY
Delay rendering of this node until the second pass
}

Methods from class SoGLRenderAction:

SoGLRenderAction(const SbViewportRegion &viewportRegion)
void
setViewportRegion(const SbViewportRegion &newRegion)
const SbViewportRegion &
getViewportRegion() const
void
setUpdateArea(const SbVec2f &origin, const SbVec2f &size)
void
getUpdateArea(SbVec2f &origin, SbVec2f &size) const
void
setAbortCallback(SoGLRenderAbortCB *func, void *userData)
void
setTransparencyType(TransparencyType type)
TransparencyType
getTransparencyType() const
void
setSmoothing(SbBool smooth)
SbBool
isSmoothing() const
void
setNumPasses(int num)
int
getNumPasses() const
void
setPassUpdate(SbBool flag)
SbBool
isPassUpdate() const
void
setPassCallback(SoGLRenderPassCB *func, void *userData)
void
setCacheContext(uint32_t context)
uint32_t
getCacheContext() const

Methods from class SoAction:

virtual void
apply(SoNode *node)
virtual void
apply(SoPath *path)
virtual void
apply(const SoPathList &pathList, SbBool obeysRules = FALSE)
static SoType
getClassTypeId()
virtual SoType
getTypeId()
virtual SbBool
isOfType(SoType type)
virtual void
invalidateState()

DESCRIPTION
This class traverses a scene graph and renders it using the OpenGL graphics library. It assumes that a valid window has been created and initialized for proper OpenGL rendering. The SoXtRenderArea class or any of its subclasses may be used to create such a window.

METHODS

SoGLRenderAction(const SbViewportRegion &viewportRegion)
Constructor. The parameter defines the viewport region into which rendering will take place.

void
setViewportRegion(const SbViewportRegion &newRegion)
const SbViewportRegion &
getViewportRegion() const
Changes/returns viewport region to use for rendering.

void
setUpdateArea(const SbVec2f &origin, const SbVec2f &size)
void
getUpdateArea(SbVec2f &origin, SbVec2f &size) const
Sets/returns the current update area, which is the rectangular area of the viewport region that will actually be rendered into. This can be used for partial updates in applications that can manage them. The update area is specified in normalized viewport coordinates, where (0,0) is the lower left corner of the viewport and (1,1) is the upper right corner. The area is specified or returned as an origin and a size.

void
setAbortCallback(SoGLRenderAbortCB *func, void *userData)
Sets callback to call during rendering to test for an abort condition. It will be called for each node that is traversed. This allows applications to terminate rendering prematurely if some condition occurs. The callback function should return one of the AbortCode codes to indicate whether traversal should continue. Use of the various codes in a callback can allow applications to modify Inventor's default order of rendering objects in a scene graph.

void
setTransparencyType(TransparencyType type)
TransparencyType
getTransparencyType() const
Sets/returns transparency quality level to use when rendering. The default is SCREEN_DOOR. (Note that SCREEN_DOOR transparency does not work in the case where transparency values are specified for each vertex of a shape. If this is the case, use one of the other transparency types.)

void
setSmoothing(SbBool smooth)
SbBool
isSmoothing() const
Sets/returns smoothing flag. When on, smoothing uses OpenGL's line- and point-smoothing features to provide cheap antialiasing of lines and points. The default is FALSE.

void
setNumPasses(int num)
int
getNumPasses() const
Sets/returns number of rendering passes for multipass rendering. Specifying more than one pass will result in antialiasing of the rendered scene, using OpenGL's accumulation buffer. (Camera nodes typically move their viewpoints a little bit for each pass to achieve the antialiasing.) Each additional pass provides better antialiasing, but requires more rendering time The default is 1 pass.

void
setPassUpdate(SbBool flag)
SbBool
isPassUpdate() const
Sets/returns a flag indicating whether intermediate results are displayed after each antialiasing pass for progressive improvement (default is FALSE).

void
setPassCallback(SoGLRenderPassCB *func, void *userData)
Sets a callback function to invoke between passes when antialiasing. Passing NULL (which is the default state) will cause a clear of the color and depth buffers to be performed.

void
setCacheContext(uint32_t context)
uint32_t
getCacheContext() const
Sets/returns the OpenGL cache context. A cache context is just an integer identifying when OpenGL display lists (which are used for render caching) can be shared between render actions; for example, see the documentation on GLX contexts for information on when OpenGL display lists can be shared between GLX windows.

SEE ALSO
SoSeparator, SoXtRenderArea