Take the sample *transparency* as a reference. I created a scene = 27 cubes + 1 parallelogram (square). I expected that OptiX can help me to speedup a program.

*1 version*:

As in transparency, without sphere, 27 boxes instead of 9, floor.

Thus I created 28 (27 + 1) geometries and 28 geometryinstaces. Then 1 geometrygroup GG including those. I tried several variants, e.g.

```
GG->setAcceleration( m_context->createAcceleration("Lbvh","Bvh") );
GG->setAcceleration( m_context->createAcceleration("Trbvh","Bvh") );
GG->setAcceleration( m_context->createAcceleration("NoAccel","NoAccel") );
```

All variants demonstrate almost the same time.

*2 version - Another scene graph*:

```
boxes = new BOX [27];
Geometry box = m_context->createGeometry();
box->setPrimitiveCount( 27u );
box->setBoundingBoxProgram( box_bounds );
box->setIntersectionProgram( box_intersect );
Material box_matl = m_context->createMaterial();
box_matl->setClosestHitProgram( CRL_DIRECT_RAY_TYPE, transparent_ch );
box_matl["refraction_index"]->setFloat( 1.2f );
...
// Floor
Geometry parallelogram = m_context->createGeometry();
parallelogram->setPrimitiveCount( 1u );
...
GeometryInstance gi = m_context->createGeometryInstance();
gi->setGeometry( box );
gi->setMaterialCount( 1 );
gi->setMaterial( 0, box_matl );
GeometryInstance gf = m_context->createGeometryInstance();
gf->setGeometry( parallelogram );
gf->setMaterialCount( 1 );
gf->setMaterial( 0, floor_matl );
GeometryGroup geometrygroupbox = m_context->createGeometryGroup();
// beneath: several attempts with accels. All
//geometrygroupbox->setAcceleration( m_context->createAcceleration("Lbvh","Bvh") );
geometrygroupbox->setAcceleration( m_context->createAcceleration("Trbvh","Bvh") );
//geometrygroupbox->setAcceleration( m_context->createAcceleration("NoAccel","NoAccel") );
geometrygroupbox->setChildCount( 1u );
geometrygroupbox->setChild( 0, gi );
GeometryGroup geometrygroupflo = m_context->createGeometryGroup();
//geometrygroupflo->setAcceleration( m_context->createAcceleration("Lbvh","Bvh") );
geometrygroupflo->setAcceleration( m_context->createAcceleration("NoAccel","NoAccel") );
geometrygroupflo->setChildCount( 1u );
geometrygroupflo->setChild( 0, gf );
Group gr = m_context->createGroup();
gr->setChildCount(2);
gr->setChild(0, geometrygroupbox);
gr->setChild(1, geometrygroupflo);
gr->setAcceleration( m_context->createAcceleration("NoAccel","NoAccel") );
m_context["top_object"]->set( gr );
```

All variants of accel demonstrate almost the same time too.

Does it mean that from acceleration point of view the word “primitive” means “triangle”? I.e., an acceleration of other primitive types are not supported.