fsleyes.render

The render module is a program which provides off-screen rendering capability for scenes which can otherwise be displayed via FSLeyes.

fsleyes.render.main(args=None, hook=None)

Entry point for render.

Creates and renders an OpenGL scene, and saves it to a file, according to the specified command line arguments (which default to sys.argv[1:]).

fsleyes.render.parseArgs(argv)

Creates an argument parser which accepts options for off-screen rendering. Uses the fsleyes.parseargs module to peform the actual parsing.

Returns

An argparse.Namespace object containing the parsed arguments.

fsleyes.render.makeDisplayContext(namespace)

Creates OverlayList, DisplayContext`, and SceneOpts instances which represent the scene to be rendered, as described by the arguments in the given namespace object.

fsleyes.render.render(namespace, overlayList, displayCtx, sceneOpts, hook=None)

Renders the scene, and returns a tuple containing the bitmap and the background colour.

Parameters

• namespace – argparse.Namespace object containing command line arguments.

• overlayList – The OverlayList instance.

• displayCtx – The DisplayContext instance.

• sceneOpts – The SceneOpts instance.

• hook – Function which is called after the canvases have been created, but before the scene is rendered. Can be used to perform any configuration/drawing in addition to that specified via namespace.

Note

The hook argument was added for testing purposes, but may be useful in other situations.

fsleyes.render.createLightBoxCanvas(namespace, width, height, overlayList, displayCtx, sceneOpts)

Creates, configures, and returns an OffScreenLightBoxCanvas.

Parameters

• namespace – argparse.Namespace object.

• width – Available width in pixels.

• height – Available height in pixels.

• overlayList – The OverlayList instance.

• displayCtx – The DisplayContext instance.

• sceneOpts – The SceneOpts instance.

fsleyes.render.createOrthoCanvases(namespace, width, height, overlayList, displayCtx, sceneOpts)

Creates, configures, and returns up to three OffScreenSliceCanvas instances, for rendering the scene.

Parameters

• namespace – argparse.Namespace object.

• width – Available width in pixels.

• height – Available height in pixels.

• overlayList – The OverlayList instance.

• displayCtx – The DisplayContext instance.

• sceneOpts – The SceneOpts instance.

fsleyes.render.create3DCanvas(namespace, width, height, overlayList, displayCtx, sceneOpts)

Creates, configures, and returns an OffScreenScene3DCanvas.

Parameters

• namespace – argparse.Namespace object.

• width – Available width in pixels.

• height – Available height in pixels.

• overlayList – The OverlayList instance.

• displayCtx – The DisplayContext instance.

• sceneOpts – The SceneOpts instance.

fsleyes.render.buildColourBarBitmap(overlayList, displayCtx, width, height, sceneOpts)

If the currently selected overlay has a display range, creates and returns a bitmap containing a colour bar. Returns None otherwise.

Parameters

• overlayList – The OverlayList.

• displayCtx – The DisplayContext.

• width – Colour bar width in pixels.

• height – Colour bar height in pixels.

• sceneOpts – SceneOpts instance containing display settings.

fsleyes.render.buildColourBarLayout(canvasLayout, cbarBmp, cbarLocation, cbarLabelSide)

Given a layout object containing the rendered canvas bitmaps, creates a new layout which incorporates the given colour bar bitmap.

Parameters

• canvasLayout – An object describing the canvas layout (see fsleyes_widgets.utils.layout)

• cbarBmp – A bitmap containing a rendered colour bar.

• cbarLocation – Colour bar location (see buildColourBarBitmap()).

• cbarLabelSide – Colour bar label side (see buildColourBarBitmap()).

fsleyes.render.adjustSizeForColourBar(width, height, showColourBar, colourBarLocation, fontSize)

Calculates the widths and heights of the image display space, and the colour bar if it is enabled.

Parameters

• width – Desired width in pixels

• height – Desired height in pixels

• showColourBar – True if a colour bar is to be shown, False otherwise.

• colourBarLocation – Colour bar location (see buildColourBarBitmap()).

:arg fontSize Font size (points) used in colour bar labels.

Returns

Two tuples - the first tuple contains the (width, height) of the available canvas space, and the second contains the (width, height) of the colour bar.

fsleyes.render.calculateOrthoCanvasSizes(overlayList, displayCtx, width, height, canvasAxes, layout)

Calculates the sizes, in pixels, for each canvas to be displayed in an orthographic layout.

Parameters

• overlayList – The OverlayList.

• displayCtx – The DisplayContext.

• width – Available width in pixels.

• height – Available height in pixels.

• canvasAxes – A sequence of (xax, yax) indices, one for each bitmap in canvasBmps.

• layout – Either 'horizontal', 'vertical', or 'grid', describing the canvas layout.

Returns

A list of (width, height) tuples, one for each canvas, each specifying the canvas width and height in pixels.

fsleyes.render.autocrop(data, bgColour, border=0)

Crops the given bitmap image on all sides where the bgColour is the only colour present.

If the image is completely empty. it is not cropped.

Parameters

• data – numpy array of shape (w, h, 4) containing the image.

• bgColour – Sequence of length 4 containing the background colour to crop.

• border – Number of pixels to leave around each side.

class fsleyes.render.MockSliceCanvas

Bases: object

Used in place of a SliceCanvas. The parseargs module needs access to SliceCanvas instances to apply some command line options. However, render calls parseargs.applySceneArgs() before any SliceCanvas instances have been created.

Instances of this class are just used to capture those options, so they can later be applied to the real SliceCanvas instances.

The following arguments may be applied to this class.

• --xcentre

• --ycentre

• --zcentre

__init__()

Initialize self. See help(type(self)) for accurate signature.

centreDisplayAt(x, y)

__dict__ = mappingproxy({'__module__': 'fsleyes.render', '__doc__': 'Used in place of a :class:`.SliceCanvas`. The :mod:`.parseargs` module\n needs access to ``SliceCanvas`` instances to apply some command line\n options. However, ``render`` calls :func:`.parseargs.applySceneArgs`\n before any ``SliceCanvas`` instances have been created.\n\n Instances of this class are just used to capture those options, so they\n can later be applied to the real ``SliceCanvas`` instances.\n\n The following arguments may be applied to this class.\n - ``--xcentre``\n - ``--ycentre``\n - ``--zcentre``\n ', '__init__': <function MockSliceCanvas.__init__>, 'centreDisplayAt': <function MockSliceCanvas.centreDisplayAt>, '__dict__': <attribute '__dict__' of 'MockSliceCanvas' objects>, '__weakref__': <attribute '__weakref__' of 'MockSliceCanvas' objects>, '__annotations__': {}})

__module__ = 'fsleyes.render'

__weakref__

list of weak references to the object (if defined)

class fsleyes.render.MockCanvasPanel(ncanvases)

Bases: object

Used in place of a CanvasPanel. This is used as a container for MockSliceCanvas instances.

__init__(ncanvases)

Initialize self. See help(type(self)) for accurate signature.

getGLCanvases()

__dict__ = mappingproxy({'__module__': 'fsleyes.render', '__doc__': 'Used in place of a :class:`.CanvasPanel`. This is used as a container\n for :class:`MockSliceCanvas` instances.\n ', '__init__': <function MockCanvasPanel.__init__>, 'getGLCanvases': <function MockCanvasPanel.getGLCanvases>, '__dict__': <attribute '__dict__' of 'MockCanvasPanel' objects>, '__weakref__': <attribute '__weakref__' of 'MockCanvasPanel' objects>, '__annotations__': {}})

__module__ = 'fsleyes.render'

__weakref__

list of weak references to the object (if defined)

class fsleyes.render.MockOrthoPanel(canvases)

Bases: object

Used in place of an OrthoPanel. This is used as a container for three SliceCanvas instances.

__init__(canvases)

Initialize self. See help(type(self)) for accurate signature.

getGLCanvases()

getXCanvas()

getYCanvas()

getZCanvas()

__dict__ = mappingproxy({'__module__': 'fsleyes.render', '__doc__': 'Used in place of an :class:`.OrthoPanel`. This is used as a container\n for three :class:`SliceCanvas` instances.\n ', '__init__': <function MockOrthoPanel.__init__>, 'getGLCanvases': <function MockOrthoPanel.getGLCanvases>, 'getXCanvas': <function MockOrthoPanel.getXCanvas>, 'getYCanvas': <function MockOrthoPanel.getYCanvas>, 'getZCanvas': <function MockOrthoPanel.getZCanvas>, '__dict__': <attribute '__dict__' of 'MockOrthoPanel' objects>, '__weakref__': <attribute '__weakref__' of 'MockOrthoPanel' objects>, '__annotations__': {}})

__module__ = 'fsleyes.render'

__weakref__

list of weak references to the object (if defined)