from direct.filter.FilterManager import FilterManager

The FilterManager is a convenience class that helps with the creation of render-to-texture buffers for image postprocessing applications.

See Generalized Image Filters for information on how to use this class.

Still need to implement:

  • Make sure sort-order of buffers is correct.

  • Matching buffer size to original region instead of original window.

  • Intermediate layer creation.

  • Handling of window clears.

  • Resizing of windows.

  • Do something about window-size roundoff problems.

Inheritance diagram

Inheritance diagram of direct.filter.FilterManager

class FilterManager(win, cam, forcex=0, forcey=0)[source]

Bases: direct.showbase.DirectObject.DirectObject

__init__(self, win, cam, forcex=0, forcey=0)[source]

The FilterManager constructor requires you to provide a window which is rendering a scene, and the camera which is used by that window to render the scene. These are henceforth called the ‘original window’ and the ‘original camera.’


Restore everything to its original state, deleting any new buffers in the process.

createBuffer(self, name, xsize, ysize, texgroup, depthbits=1, fbprops=None)[source]

Low-level buffer creation. Not intended for public use.

getClears(self, region)[source]
getScaledSize(self, mul, div, align)[source]

Calculate the size of the desired window. Not public.

notify = None
renderQuadInto(self, name='filter-stage', mul=1, div=1, align=1, depthtex=None, colortex=None, auxtex0=None, auxtex1=None, fbprops=None)[source]

Creates an offscreen buffer for an intermediate computation. Installs a quad into the buffer. Returns the fullscreen quad. The size of the buffer is initially equal to the size of the main window. The parameters ‘mul’, ‘div’, and ‘align’ can be used to adjust that size.

renderSceneInto(self, depthtex=None, colortex=None, auxtex=None, auxbits=0, textures=None, fbprops=None, clamping=None)[source]

Causes the scene to be rendered into the supplied textures instead of into the original window. Puts a fullscreen quad into the original window to show the render-to-texture results. Returns the quad. Normally, the caller would then apply a shader to the quad.

To elaborate on how this all works:

  • An offscreen buffer is created. It is set up to mimic the original display region - it is the same size, uses the same clear colors, and contains a DisplayRegion that uses the original camera.

  • A fullscreen quad and an orthographic camera to render that quad are both created. The original camera is removed from the original window, and in its place, the orthographic quad-camera is installed.

  • The fullscreen quad is textured with the data from the offscreen buffer. A shader is applied that tints the results pink.

  • Automatic shader generation NOT enabled. If you have a filter that depends on a render target from the auto-shader, you either need to set an auto-shader attrib on the main camera or scene, or, you need to provide these outputs in your own shader.

  • All clears are disabled on the original display region. If the display region fills the whole window, then clears are disabled on the original window as well. It is assumed that rendering the full-screen quad eliminates the need to do clears.

Hence, the original window which used to contain the actual scene, now contains a pink-tinted quad with a texture of the scene. It is assumed that the user will replace the shader on the quad with a more interesting filter.


Resize all buffers to match the size of the window.

setClears(self, region, clears)[source]
setStackedClears(self, region, clears0, clears1)[source]
windowEvent(self, win)[source]

When the window changes size, automatically resize all buffers