PSSMCameraRig

from panda3d._rplight import PSSMCameraRig

class PSSMCameraRig

Bases: DTOOL_SUPER_BASE

This is the main class for supporting PSSM, it is used by the PSSM plugin to compute the position of the splits.

It supports handling a varying amount of cameras, and fitting those cameras into the main camera frustum, to render distant shadows. It also supports various optimizations for fitting the frustum, e.g. rotating the sources to get a better coverage.

It also provides methods to get arrays of data about the used cameras view-projection matrices and their near and far plane, which is required for processing the data in the shadow sampling shader.

In this class, there is often referred to “Splits” or also called “Cascades”. These denote the different cameras which are used to split the frustum, and are a common term related to the PSSM algorithm.

To understand the functionality of this class, a detailed knowledge of the PSSM algorithm is helpful.

Inheritance diagram

__init__(*args, **kwargs)

getCamera()

C++ Interface: get_camera(PSSMCameraRig self, int index)

/**

@brief Returns the n-th camera
@details This returns the n-th camera of the camera rig, which can be used
for various stuff like showing its frustum, passing it as a shader input,
and so on.
The first camera is the camera which is the camera of the first split,
which is the split closest to the camera. All cameras follow in descending
order until to the last camera, which is the split furthest away from the
camera.
If an invalid index is passed, an assertion is thrown.
@param index Index of the camera.
@return [description]

*/

getMvpArray()

C++ Interface: get_mvp_array(PSSMCameraRig self)

/**

@brief Returns a handle to the MVP array
@details This returns a handle to the array of view-projection matrices
of the different splits. This can be used for computing shadows. The array
is a PTALMatrix4 and thus can be directly bound to a shader.
@return view-projection matrix array

*/

getNearfarArray()

C++ Interface: get_nearfar_array(PSSMCameraRig self)

/**

@brief Returns a handle to the near and far planes array
@details This returns a handle to the near and far plane array. Each split
has an entry in the array, whereas the x component of the vecto denotes the
near plane, and the y component denotes the far plane of the split.
This is required because the near and far planes of the splits change
constantly. To access them in a shader, the shader needs access to the
array.
@return Array of near and far planes

*/

get_camera()

C++ Interface: get_camera(PSSMCameraRig self, int index)

/**

@brief Returns the n-th camera
@details This returns the n-th camera of the camera rig, which can be used
for various stuff like showing its frustum, passing it as a shader input,
and so on.
The first camera is the camera which is the camera of the first split,
which is the split closest to the camera. All cameras follow in descending
order until to the last camera, which is the split furthest away from the
camera.
If an invalid index is passed, an assertion is thrown.
@param index Index of the camera.
@return [description]

*/

get_mvp_array()

C++ Interface: get_mvp_array(PSSMCameraRig self)

/**

@brief Returns a handle to the MVP array
@details This returns a handle to the array of view-projection matrices
of the different splits. This can be used for computing shadows. The array
is a PTALMatrix4 and thus can be directly bound to a shader.
@return view-projection matrix array

*/

get_nearfar_array()

C++ Interface: get_nearfar_array(PSSMCameraRig self)

/**

@brief Returns a handle to the near and far planes array
@details This returns a handle to the near and far plane array. Each split
has an entry in the array, whereas the x component of the vecto denotes the
near plane, and the y component denotes the far plane of the split.
This is required because the near and far planes of the splits change
constantly. To access them in a shader, the shader needs access to the
array.
@return Array of near and far planes

*/

reparentTo()

C++ Interface: reparent_to(const PSSMCameraRig self, NodePath parent)

/**

@brief Reparents the camera rig
@details This reparents all cameras to the given parent. Usually the parent
will be ShowBase.render. The parent should be the same node where the
main camera is located in, too.
If an empty parrent is passed, an assertion will get triggered.
@param parent Parent node path

*/

reparent_to()

C++ Interface: reparent_to(const PSSMCameraRig self, NodePath parent)

/**

@brief Reparents the camera rig
@details This reparents all cameras to the given parent. Usually the parent
will be ShowBase.render. The parent should be the same node where the
main camera is located in, too.
If an empty parrent is passed, an assertion will get triggered.
@param parent Parent node path

*/

resetFilmSizeCache()

C++ Interface: reset_film_size_cache(const PSSMCameraRig self)

/**

@brief Resets the film size cache
@details In case PSSMCameraRig::set_use_fixed_film_size is used, this resets
the film size cache. This might lead to a small “jump” in the shadows,
because the film size changes, however it leads to a better shadow distribution.
This is the case because when using a fixed film size, the cache will get
bigger and bigger, whenever the camera moves to a grazing angle. However,
when moving back to a normal angle, the film size cache still stores this
big angle, and thus the splits will have a much bigger film size than actualy
required. To prevent this, call this method once in a while, so an optimal
distribution is ensured.

*/

reset_film_size_cache()

C++ Interface: reset_film_size_cache(const PSSMCameraRig self)

/**

@brief Resets the film size cache
@details In case PSSMCameraRig::set_use_fixed_film_size is used, this resets
the film size cache. This might lead to a small “jump” in the shadows,
because the film size changes, however it leads to a better shadow distribution.
This is the case because when using a fixed film size, the cache will get
bigger and bigger, whenever the camera moves to a grazing angle. However,
when moving back to a normal angle, the film size cache still stores this
big angle, and thus the splits will have a much bigger film size than actualy
required. To prevent this, call this method once in a while, so an optimal
distribution is ensured.