modifications of the osgShadow header naming styles as well. The
osgDB::Serializer header is also changed to add new Vec2 serializer
macros because of the needs of osgShadow classes. It should compile
fine on both Windows and Linux. But I have only done a few tests to
generate .osgb, .osgt and .osgx formats with these new wrappers."
up vector to setViewMatrixAsLookAt(..) codes in osgShadow. This will addresses previous issues that occured when look vectors
co-incided with the hard coded up vectors.
Fixes in StandardShadowMap.cpp & MinimalShadowMap.cpp were made for spotlight issues. There were cases when further located spotlights were not shadowing properly.
Small tweak in DebugShadowMap & StandardShadowMap.cpp to not limit shadow maps to texture2D (which should also allow texture2D arrays and cube maps). I simply replaced ptr to osg::Texture2D with pointer to osg::Texture. Interpretation of this member could be now changed with change of shaders in derived classes. This may be useful for guys who override LispSM or MinimalBoundsShadowMaps techniques. Could be useful for implementation of PerspectiveCascadedShadowMaps technique for example.
ConvexPolyhedron.cpp & DebugShadowMap.cpp contain debug HUD tweaks.
Change in ConvexPolyhedron.cpp overcomes the regression problem with color per primitive binding which caused that shadow volume outlines stopped to draw. I simply changed PER_PRIMITIVE to PER_PRIMITIVE_SET and it works again.
Other adition is dump method I added to DebugShadowMap which can be used in shadow debugging mode to dump current frame shadow volumes & scene to osg file. It could be then loaded into viewer and freely examined from different angles (which is difficult inside the application if shadow adopts to view and projection). "
Also, there was also a small bug in osgDB's CMakeLists.txt that was causing an error when I tested with CMake 2.4.4.
IF(${OSG_DEFAULT_IMAGE_PLUGIN_FOR_OSX} STREQUAL "quicktime")
was changed to
IF(OSG_DEFAULT_IMAGE_PLUGIN_FOR_OSX STREQUAL "quicktime")
"
"Soft shadow mapping is basically the same as hard shadow mapping beside that
it uses a different fragment shader.
So for me it makes sense that osgShadow::SoftShadowMap is derived from
osgShadow::ShadowMap, this makes it easier to maintain the two classes.
Additional SoftShadowMap also provides the same Debug methods as ShadowMap."
I think I may have discovered a bug in osgShadow/ShadowMap.cpp that results in incomplete shadows being generated.
The problem seems to caused by an incorrect interpretation of the spot light cutoff angle. The valid ranges for spot cutoff are 0-90 and 180, i.e half the 'field of view' for the spotlight. Whereas the shadow map code seems to assume the the spot cutoff is equal to the field of view. This results in the shadows generated by the spotlight getting clipped at half the spot cutoff angle.
I have fixed this in my copy of ShadowMap.cpp:
===============================
//Original code from OSG 2.6:
if(selectLight->getSpotCutoff() < 180.0f) // spotlight, then we don't need the bounding box
{
osg::Vec3 position(lightpos.x(), lightpos.y(), lightpos.z());
float spotAngle = selectLight->getSpotCutoff();
_camera->setProjectionMatrixAsPerspective(spotAngle, 1.0, 0.1, 1000.0);
_camera->setViewMatrixAsLookAt(position,position+lightDir,osg::Vec3(0.0f,1.0f,0.0f));
}
===============================
// My modifications:
float fov = selectLight->getSpotCutoff() * 2;
if(fov < 180.0f) // spotlight, then we don't need the bounding box
{
osg::Vec3 position(lightpos.x(), lightpos.y(), lightpos.z());
_camera->setProjectionMatrixAsPerspective(fov, 1.0, 0.1, 1000.0);
_camera->setViewMatrixAsLookAt(position,position+lightDir,osg::Vec3(0.0f,1.0f,0.0f));
}
This change seems correct for spot cutoff in the range 0, 90, but since OpenGL doesn't claim to support cutoffs >90 && <180, I'm not sure how shadow map should deal with those cases, but ignoring spot cut off greater than 90 here seems reasonable to me.
"
polygon offset complicate. so i looked for a solution to remove this offset.
i changed the shader, also the filtering (default: on) use now a correct 3x3 filter:
1 0 1
0 2 0
1 0 1
div: 6
of course a better one would be
1 2 1
2 4 2
1 2 1
div: 16
but this isn't as performant as the simple filter above is. because we need only 5 texture lookups instead of 9, and the result is still good, if you wish we can add a enum to change the pcf filter type once, if there is a need.
testet on NVidia Quatro 570M and on ATI Radeon X1600
"
unfort. i couldn't test it on any ATI system. may there will be still another problem there. if there are still some artefacts. we should try out better fZOffSet value
"
1:
Shadow map camera sets ABSOLUTE_RF_INHERIT_VIEWPOINT refernce frame.
2:
Light Direction by matrix multiplications replaced with transform3x3 multiplication.
3:
I made DebugingHUD functional by adding special draw callback. Former version was simply drawing pale square.
4:
I was tempted to make 4 th change but decided to not do it. Instead I put it whith #if VIEW_DEPNDENT_TEXGEN. If you decide you may let it go.
When objects are not centered at 0,0,0 coord but in some distant location (for example at surface of earth ellipsoid) shadow texgen suffers from inadequate precision of float matrices. I changed that by premultiplying Texgen matrix (using OSG double matrices) with inverse modelview and applying it later with ModelView identity matrix. This tweak may be appropriate for OverlayNode texgen as well.
I left former version because I suspect that this change will make osgShadow::ShadowMap view dependant. Currently texgen matrix remains the same no matter what View displays it. With my change it wuld be different for each view. This touches the subject of View Dependent Shadow Techniques that J-S asked recently."
File osgShadow/Version.cpp, Line 25:
const char* osgShaodowGetLibraryName()
should be:
const char* osgShadowGetLibraryName()
File CMakeModules/OsgMacroUtils.cmake, Line 224:
SET_TARGET_PROPERTIES(${TARGET_TARGETNAME} PROPERTIES DEBUG_POSTFIX ${CMAKE_DEBUG_POSTFIX})
should be:
SET_TARGET_PROPERTIES(${TARGET_TARGETNAME} PROPERTIES DEBUG_POSTFIX "${CMAKE_DEBUG_POSTFIX}")
Otherwise setting CMAKE_DEBUG_POSTFIX to an empty string instead of "d" in
the main CMakeLists.txt does not work under Linux.
"