scene
¶
This module provides a 3D graphics scene graph structure.
axes
: Bounding Box with axes ticks and labels¶
Primitive displaying a text field in the scene.

class
LabelledAxes
[source]¶ A group displaying a bounding box with axes labels around its children.

tickColor
¶ Color of ticks and text labels.
This does NOT set bounding box color. Use
color
for the bounding box.

font
¶ Font of axes text labels (Font)

xlabel
¶ Text label of the X axis (str)

ylabel
¶ Text label of the Y axis (str)

zlabel
¶ Text label of the Z axis (str)

boxVisible
¶ Returns bounding box, axes labels and grid visibility.

camera
: Projection management classes¶
This module provides classes to handle a perspective projection in 3D.

class
CameraExtrinsic
(position=(0.0, 0.0, 0.0), direction=(0.0, 0.0, 1.0), up=(0.0, 1.0, 0.0))[source]¶ Transform matrix to handle camera position and orientation.
Parameters:  position (numpy.ndarraylike of 3 float32.) – Coordinates of the point of view.
 direction (numpy.ndarraylike of 3 float32.) – Sight direction vector.
 up (numpy.ndarraylike of 3 float32.) – Vector pointing upward in the image plane.

setOrientation
(direction=None, up=None)[source]¶ Set the rotation of the point of view.
Parameters:  direction (numpy.ndarraylike of 3 float32 or None.) – Sight direction vector or None to keep the current one.
 up (numpy.ndarraylike of 3 float32 or None.) – Vector pointing upward in the image plane or None to keep the current one.
Raises: RuntimeError – if the direction and up are parallel.

position
¶ Coordinates of the point of view as a numpy.ndarray of 3 float32.

direction
¶ Sight direction (ndarray of 3 float32).

up
¶ Vector pointing upward in the image plane (ndarray of 3 float32).

side
¶ Vector pointing towards the side of the image plane.
ndarray of 3 float32

move
(direction, step=1.0)[source]¶ Move the camera relative to the image plane.
Parameters:  direction (str) – Direction relative to image plane. One of: ‘up’, ‘down’, ‘left’, ‘right’, ‘forward’, ‘backward’.
 step (float) – The step of the pan to perform in the coordinate in which the camera position is defined.

rotate
(direction, angle=1.0)[source]¶ Firstperson rotation of the camera towards the direction.
Parameters:  direction (str) – Direction of movement relative to image plane. In: ‘up’, ‘down’, ‘left’, ‘right’.
 angle (float) – The angle in degrees of the rotation.

orbit
(direction, center=(0.0, 0.0, 0.0), angle=1.0)[source]¶ Rotate the camera around a point.
Parameters:  direction (str) – Direction of movement relative to image plane. In: ‘up’, ‘down’, ‘left’, ‘right’.
 center (numpy.ndarraylike of 3 float32.) – Position around which to rotate the point of view.
 angle (float) – he angle in degrees of the rotation.

class
Camera
(fovy=30.0, near=0.1, far=1.0, size=(1.0, 1.0), position=(0.0, 0.0, 0.0), direction=(0.0, 0.0, 1.0), up=(0.0, 1.0, 0.0))[source]¶ Combination of camera projection and position.
See
Perspective
andCameraExtrinsic
.Parameters:  fovy (float) – Vertical fieldofview in degrees.
 near (float) – The near clipping plane Z coord (strictly positive).
 far (float) – The far clipping plane Z coord (> near).
 size (2tuple of float) – Viewport’s size used to compute the aspect ratio (width, height).
 position (numpy.ndarraylike of 3 float32.) – Coordinates of the point of view.
 direction (numpy.ndarraylike of 3 float32.) – Sight direction vector.
 up (numpy.ndarraylike of 3 float32.) – Vector pointing upward in the image plane.

resetCamera
(bounds)[source]¶ Change camera to have the bounds in the viewing frustum.
It updates the camera position and depth extent. Camera sight direction and up are not affected.
Parameters: bounds (numpy.ndarray: ((xMin, yMin, zMin), (xMax, yMax, zMax))) – The axesaligned bounds to include.

intrinsic
¶ Intrinsic camera parameters, i.e., projection matrix.

extrinsic
¶ Extrinsic camera parameters, i.e., position and orientation.
core
: Base class of the scene nodes¶
This module provides the base scene structure.
This module provides the classes for describing a tree structure with
rendering and picking API.
All nodes inherit from Base
.
Nodes with children are provided with PrivateGroup
and
Group
classes.
Leaf rendering nodes should inherit from Elem
.

class
Base
[source]¶ A scene node with common features.

visible
¶ Visibility flag of the node

pickable
¶ True to make node pickable

parent
¶ Parent or None if no parent

path
¶ Tuple of scene nodes, from the tip of the tree down to this node.
If this tree is attached to a
Viewport
, then theViewport
is the first element of path.

viewport
¶ The viewport this node is attached to or None.

root
¶ The root node of the scene.
If attached to a
Viewport
, this is the item right under it

objectToNDCTransform
¶ Transform from object to normalized device coordinates.
Do not forget perspective divide.

objectToSceneTransform
¶ Transform from object to scene.
Combine transforms up to the Viewport (not including it).

transforms
¶ List of transforms defining the frame of this node relative to its parent.

bounds
(transformed=False, dataBounds=False)[source]¶ Returns the bounds of this node aligned with the axis, with or without transform applied.
Parameters:  transformed (bool) – False to give bounds in object coordinates (the default), True to apply this object’s transforms.
 dataBounds (bool) – False to give bounds of vertices (the default), True to give bounds of the represented data.
Returns: The bounds: ((xMin, yMin, zMin), (xMax, yMax, zMax)) or None if no bounds.
Return type: numpy.ndarray of float

prepareGL2
(ctx)[source]¶ Called before the rendering to prepare OpenGL resources.
Override in subclass.


class
PrivateGroup
(children=())[source]¶ A scene node that renders its (private) childern.
Parameters: children (iterable) – Base
nodes to add as children
class
ChildrenList
(parent, children)[source]¶ List of children with notification and children’s parent update.

class
cutplane
: Cutting plane primitive¶
A cut plane in a 3D texture: hackish implementation…

class
ColormapMesh3D
(position, normal, data, copy=True, mode='triangles', indices=None, colormap=None)[source]¶ A 3D mesh with color from a 3D texture.

textureOffset
= None¶ Offset to add to texture coordinates

interpolation
¶ The texture interpolation mode: ‘linear’ or ‘nearest’

alpha
¶ Transparency of the plane, float in [0, 1]

colormap
¶ The colormap used by this primitive


class
CutPlane
(point=(0.0, 0.0, 0.0), normal=(0.0, 0.0, 1.0))[source]¶ A cutting plane in a 3D texture

interpolation
¶ The texture interpolation mode: ‘linear’ (default) or ‘nearest’

prepareGL2
(ctx)[source]¶ Called before the rendering to prepare OpenGL resources.
Override in subclass.

contourVertices
¶ The vertices of the contour of the plane/bounds intersection.

transforms
¶ List of transforms defining the frame of this node relative to its parent.

event
: Scene event system¶
This module provides a simple generic notification system.

class
Notifier
[source]¶ Base class for object with notification mechanism.

addListener
(listener)[source]¶ Register a listener.
Adding an already registered listener has no effect.
Parameters: listener (callable) – The function or method to register.


notifyProperty
(attrName, copy=False, converter=None, doc=None)[source]¶ Create a property that adds notification to an attribute.
Parameters:  attrName (str) – The name of the attribute to wrap.
 copy (bool) – Whether to return a copy of the attribute or not (the default).
 converter – Function converting input value to appropriate type This function takes a single argument and return the converted value. It can be used to perform some asserts.
 doc (str) – The docstring of the property
Returns: A property with getter and setter

class
HookList
(iterable)[source]¶ List with hooks before and after modification.

remove
(*args, **kwargs)[source]¶ Remove first occurrence of value.
Raises ValueError if the value is not present.

pop
(*args, **kwargs)[source]¶ Remove and return item at index (default last).
Raises IndexError if list is empty or index is out of range.

sort
(*args, **kwargs)[source]¶ Sort the list in ascending order and return None.
The sort is inplace (i.e. the list itself is modified) and stable (i.e. the order of two equal elements is maintained).
If a key function is given, apply it once to each list item and sort them, ascending or descending, according to their function values.
The reverse flag can be set to sort in descending order.

function
: OpenGL shader functions¶
This module provides functions to add to shaders.

class
ProgramFunction
[source]¶ Class providing a function to add to a GLProgram shaders.

setupProgram
(context, program)[source]¶ Setsup uniforms of a program using this shader function.
Parameters:  context (RenderContext) – The current rendering context
 program (GLProgram) – The program to setup. It MUST be in use and using this function.


class
Fog
[source]¶ Linear fog over the whole scene content.
The background of the viewport is used as fog color, otherwise it defaults to white.

isOn
¶ True to enable fog, False to disable (bool)

setupProgram
(context, program)[source]¶ Setsup uniforms of a program using this shader function.
Parameters:  context (RenderContext) – The current rendering context
 program (GLProgram) – The program to setup. It MUST be in use and using this function.


class
ClippingPlane
(point=(0.0, 0.0, 0.0), normal=(0.0, 0.0, 0.0))[source]¶ Description of a clipping plane and rendering.
Convention: Clipping is performed in camera/eye space.
Parameters:  point (numpy.ndarraylike of 3 float32) – Local coordinates of a point on the plane.
 normal (numpy.ndarraylike of 3 float32) – Local coordinates of the plane normal.

plane
¶ Plane parameters in camera space.

setupProgram
(context, program)[source]¶ Setsup uniforms of a program using this shader function.
Parameters:  context (RenderContext) – The current rendering context
 program (GLProgram) – The program to setup. It MUST be in use and using this function.

class
DirectionalLight
(direction=None, ambient=(1.0, 1.0, 1.0), diffuse=(0.0, 0.0, 0.0), specular=(1.0, 1.0, 1.0), shininess=0)[source]¶ Description of a directional Phong light.
Parameters:  direction (ndarray of 3 floats or None) – The direction of the light or None to disable light
 ambient (ndarray of 3 floats in [0, 1], default: (1., 1., 1.)) – RGB ambient light
 diffuse (ndarray of 3 floats in [0, 1], default: (0., 0., 0.)) – RGB diffuse light parameter
 specular (ndarray of 3 floats in [0, 1], default: (1., 1., 1.)) – RGB specular light parameter
 shininess (int) – The shininess of the material for specular term, default: 0 which disables specular component.

isOn
¶ True if light is on, False otherwise.

turnOff
()[source]¶ Context manager to temporary turn off lighting during rendering.
>>> with light.turnOff(): ... # Do some rendering without lighting

direction
¶ The direction of the light, or None if light is not on.

fragmentDef
¶ Definition to add to fragment shader

fragmentCall
¶ Function name to call in fragment shader

setupProgram
(context, program)[source]¶ Setsup uniforms of a program using this shader function.
Parameters:  context (RenderContext) – The current rendering context
 program (GLProgram) – The program to setup. It MUST be in use and using this function.

class
Colormap
(colormap=None, norm='linear', gamma=0.0, range_=(1.0, 10.0))[source]¶ 
NORMS
= ('linear', 'log', 'sqrt', 'gamma', 'arcsinh')¶ Tuple of supported normalizations.

decl
¶ Source code of the function declaration

colormap
¶ Color lookup table to use.

nancolor
¶ RGBA color to use for NotANumber values as 4 float in [0., 1.]

norm
¶ Normalization to use for colormap mapping.
One of ‘linear’ (the default), ‘log’ for log10 mapping or ‘sqrt’. Invalid values (e.g., negative values with ‘log’ or ‘sqrt’) are mapped to 0.

gamma
¶ Gamma correction normalization parameter (float >= 0.)

range_
¶ Range of values to map to the colormap.
2tuple of floats: (begin, end). The begin value is mapped to the origin of the colormap and the end value is mapped to the other end of the colormap. The colormap is reversed if begin > end.

displayValuesBelowMin
¶ True to display values below colormap min, False to discard them.

setupProgram
(context, program)[source]¶ Setsup uniforms of a program using this shader function.
Parameters:  context (RenderContext) – The current rendering context
 program (GLProgram) – The program to setup. It MUST be in use and using this function.

interaction
: User interaction implementation¶
This module provides interaction to plug on the scene graph.

class
ClickOrDrag
(button='left')[source]¶ Click or drag interaction for a given button.

class
ClickOrDrag
(machine)[source]¶ 
enterState
(x, y)[source]¶ Called when the state machine enters this state.
Arguments are those provided to the
goto()
method that triggered the transition to this state.

enter
(x, y)¶ Called when the state machine enters this state.
Arguments are those provided to the
goto()
method that triggered the transition to this state.


class
Drag
(machine)[source]¶ 
enterState
(initPos, curPos)[source]¶ Called when the state machine enters this state.
Arguments are those provided to the
goto()
method that triggered the transition to this state.

enter
(initPos, curPos)¶ Called when the state machine enters this state.
Arguments are those provided to the
goto()
method that triggered the transition to this state.


class

class
CameraSelectRotate
(viewport, orbitAroundCenter=True, button='right', selectCB=None)[source]¶ Camera rotation using an arcballlike interaction.

class
CameraSelectPan
(viewport, button='left', selectCB=None)[source]¶ Picking on click and pan camera on drag.

class
CameraWheel
(viewport, mode='center', scaleTransform=None)[source]¶ StateMachine like class, just handling wheel events.

class
FocusManager
(eventHandlers=(), ctrlEventHandlers=None)[source]¶ Manages focus across multiple event handlers
On press an event handler can acquire focus. By default it looses focus when all buttons are released.

class
Focus
(machine)[source]¶ 
enterState
(eventHandler, btn)[source]¶ Called when the state machine enters this state.
Arguments are those provided to the
goto()
method that triggered the transition to this state.

enter
(eventHandler, btn)¶ Called when the state machine enters this state.
Arguments are those provided to the
goto()
method that triggered the transition to this state.


class

class
RotateCameraControl
(viewport, orbitAroundCenter=False, mode='center', scaleTransform=None, selectCB=None)[source]¶ Combine wheel and rotate state machine for left button and pan when ctrl is pressed

class
PanCameraControl
(viewport, orbitAroundCenter=False, mode='center', scaleTransform=None, selectCB=None)[source]¶ Combine wheel, selectPan and rotate state machine for left button and rotate when ctrl is pressed

class
CameraControl
(viewport, orbitAroundCenter=False, mode='center', scaleTransform=None, selectCB=None)[source]¶ Combine wheel, selectPan and rotate state machine.

class
PlaneRotate
(viewport, plane, button='right')[source]¶ Plane rotation using arcball interaction.
Arcball ref.: Ken Shoemake. ARCBALL: A user interface for specifying threedimensional orientation using a mouse. In Proc. GI ‘92. (1992). pp. 151156.

class
PlanePan
(viewport, plane, button='left')[source]¶ Pan a plane along its normal on drag.

class
PlaneControl
(viewport, plane, mode='center', scaleTransform=None)[source]¶ Combine wheel, selectPan and rotate state machine for plane control.
primitives
: Base rendering primitives¶

class
Geometry
(mode, indices=None, copy=True, attrib0='position', **attributes)[source]¶ Set of vertices with normals and colors.
Parameters:  mode (str) – OpenGL drawing mode: lines, line_strip, loop, triangles, triangle_strip, fan
 indices – Array of vertex indices or None
 copy (bool) – True (default) to copy the data, False to use as is.
 attrib0 (str) – Name of the attribute that MUST be an array.
 attributes – Provide list of attributes as extra parameters.

drawMode
¶ Kind of primitive to render, in
_MODES
(str)

nbVertices
¶ Returns the number of vertices of current attributes.
It returns None if there is no attributes.

attrib0
¶ Attribute name that MUST be an array (str)

setAttribute
(name, array, copy=True)[source]¶ Set attribute with provided array.
Parameters:  name (str) – The name of the attribute
 array – Arraylike attribute data or None to remove attribute
 copy (bool) – True (default) to copy the data, False to use as is

getAttribute
(name, copy=True)[source]¶ Returns the numpy.ndarray corresponding to the name attribute.
Parameters:  name (str) – The name of the attribute to get.
 copy (bool) – True to get a copy (default), False to get internal array (DO NOT MODIFY)
Returns: The corresponding array or None if no corresponding attribute.
Return type: numpy.ndarray

useAttribute
(program, name=None)[source]¶ Enable and bind attribute(s) for a specific program.
This MUST be called with OpenGL context active and after prepareGL2 has been called.
Parameters:  program (GLProgram) – The program for which to set the attributes
 name (str) – The attribute name to set or None to set then all

setIndices
(indices, copy=True)[source]¶ Set the primitive indices to use.
Parameters:  indices – Arraylike of uint primitive indices or None to unset
 copy (bool) – True (default) to copy the data, False to use as is

getIndices
(copy=True)[source]¶ Returns the numpy.ndarray corresponding to the indices.
Parameters: copy (bool) – True to get a copy (default), False to get internal array (DO NOT MODIFY) Returns: The primitive indices array or None if not set. Return type: numpy.ndarray or None

boundsAttributeNames
¶ Tuple of attribute names defining the bounds of the object.
Attributes name are taken in the given order to compute the (x, y, z) the bounding box, e.g.:
geometry.boundsAttributeNames = 'position' geometry.boundsAttributeNames = 'x', 'y', 'z'

class
Lines
(positions, normals=None, colors=(1.0, 1.0, 1.0, 1.0), indices=None, mode='lines', width=1.0)[source]¶ A set of segments

width
¶ Width of the line in pixels.

smooth
¶ Smooth line rendering enabled (bool, default: True)


class
DashedLines
(positions, colors=(1.0, 1.0, 1.0, 1.0), indices=None, width=1.0)[source]¶ Set of dashed lines
This MUST be defined as a set of lines (no strip or loop).

dash
¶ Dash of the line as a 2tuple of lengths in pixels: (on, off)

getPositions
(copy=True)[source]¶ Get coordinates of lines.
Parameters: copy (bool) – True to get a copy, False otherwise Returns: Coordinates of lines Return type: numpy.ndarray of float32 of shape (N, 2, Ndim)


class
Box
(stroke=(1.0, 1.0, 1.0, 1.0), fill=(1.0, 1.0, 1.0, 0.0))[source]¶ Rectangular box

classmethod
getLineIndices
(copy=True)[source]¶ Returns 2D array of Box lines indices
Parameters: copy – True (default) to get a copy, False to get internal array (Do not modify!) Return type: numpy.ndarray

classmethod
getVertices
(copy=True)[source]¶ Returns 2D array of Box corner coordinates.
Parameters: copy – True (default) to get a copy, False to get internal array (Do not modify!) Return type: numpy.ndarray

size
¶ Size of the box (sx, sy, sz)

strokeSmooth
¶ True to draw smooth stroke, False otherwise

strokeWidth
¶ Width of the stroke (float)

strokeColor
¶ RGBA color of the box lines (4tuple of float in [0, 1])

fillColor
¶ RGBA color of the box faces (4tuple of float in [0, 1])

classmethod

class
BoxWithAxes
(color=(1.0, 1.0, 1.0, 1.0))[source]¶ Rectangular box with RGB OX, OY, OZ axes
Parameters: color – RGBA color of the box 
color
¶ The RGBA color to use for the box: 4 float in [0, 1]

size
¶ Size of the axes (sx, sy, sz)


class
PlaneInGroup
(point=(0.0, 0.0, 0.0), normal=(0.0, 0.0, 1.0))[source]¶ A plane using its parent bounds to display a contour.
If plane is outside the bounds of its parent, it is not visible.
Cannot set the transform attribute of this primitive. This primitive never has any bounds.

color
¶ Plane outline color (array of 4 float in [0, 1]).

width
¶ Width of the plane stroke in pixels

strokeVisible
¶ Whether surrounding stroke is visible or not (bool).

plane
¶ The plane parameters in the frame of the object.

transforms
¶ List of transforms defining the frame of this node relative to its parent.

contourVertices
¶ The vertices of the contour of the plane/bounds intersection.

center
¶ The center of the plane/bounds intersection points.

isValid
¶ True if a contour is defined, False otherwise.


class
BoundedGroup
(children=())[source]¶ Group with data bounds

shape
¶ Data shape (depth, height, width) of this group or None

size
¶ Data size (width, height, depth) of this group or None


class
Points
(x, y, z, value=0.0, size=1.0, indices=None, colormap=None)[source]¶ A set of data points with an associated value and size.

colormap
¶ The colormap used to render the image


class
ColorPoints
(x, y, z, color=(1.0, 1.0, 1.0, 1.0), size=1.0, indices=None)[source]¶ A set of points with an associated color and size.

class
GridPoints
(values=0.0, shape=None, sizes=1.0, indices=None, minValue=None, maxValue=None)[source]¶ Data points on a regular grid with an associated value and size.

class
Spheres
(positions, radius=1.0, colors=(1.0, 1.0, 1.0, 1.0))[source]¶ A set of spheres.
Spheres are rendered as circles using points. This brings some limitations:  Do not support nonuniform scaling.  Assume the projection keeps ratio.  Do not render distorion by perspective projection.  If the sphere center is clipped, the whole sphere is not displayed.

class
Mesh3D
(positions, colors, normals=None, mode='triangles', indices=None, copy=True)[source]¶ A conventional 3D mesh

culling
¶ Face culling (str)
One of ‘back’, ‘front’ or None.


class
ColormapMesh3D
(position, value, colormap=None, normal=None, mode='triangles', indices=None, copy=True)[source]¶ A 3D mesh with color computed from a colormap

lineWidth
¶ Width of the line in pixels.

lineSmooth
¶ Smooth line rendering enabled (bool, default: True)

alpha
¶ Transparency of the mesh, float in [0, 1]

culling
¶ Face culling (str)
One of ‘back’, ‘front’ or None.

colormap
¶ The colormap used to render the image


class
ImageData
(data, copy=True, colormap=None)[source]¶ Display a 2x2 data array with a texture.

colormap
¶ The colormap used to render the image


class
ImageRgba
(data, copy=True)[source]¶ Display a 2x2 RGBA image with a texture.
Supports images of float in [0, 1] and uint8.

class
GroupDepthOffset
(children=(), epsilon=None)[source]¶ A group using 2pass rendering and glDepthRange to avoid Zfighting

class
GroupNoDepth
(children=(), mask=True, notest=True)[source]¶ A group rendering its children without writing to the depth buffer
Parameters:  mask (bool) – True (default) to disable writing in the depth buffer
 notest (bool) – True (default) to disable depth test

class
GroupBBox
(children=(), color=(1.0, 1.0, 1.0, 1.0))[source]¶ A group displaying a bounding box around the children.

prepareGL2
(ctx)[source]¶ Called before the rendering to prepare OpenGL resources.
Override in subclass.

color
¶ The RGBA color to use for the box: 4 float in [0, 1]

strokeWidth
¶ The width of the stroke lines in pixels (float)

axesVisible
¶ Whether axes are displayed or not (bool)

boxVisible
¶ Whether bounding box is displayed or not (bool)

text
: Text field rendering primitives¶
Primitive displaying a text field in the scene.

class
Font
(name=None, size=1, weight=1, italic=False)[source]¶ Description of a font.
Parameters:  name (str) – Family of the font
 size (int) – Size of the font in points
 weight (int) – Font weight
 italic (bool) – True for italic font, False (default) otherwise

name
¶ Name of the font (str)

size
¶ Font size in points (int)

weight
¶ Font size in points (int)

italic
¶ True for italic (bool)

class
Text2D
(text='', font=None)[source]¶ Text field as a 2D texture displayed with billboarding
Parameters:  text (str) – Text to display
 font (Font) – The font to use

text
¶ Text displayed by this primitive (str)

font
¶ Font to use to raster text (Font)

foreground
¶ RGBA color of the text: 4 float in [0, 1]

background
¶ RGBA background color of the text field: 4 float in [0, 1]

overlay
¶ True to always display text on top of the scene (default: False)

align
¶ Horizontal anchor position of the text field (str).
Either ‘left’ (default), ‘center’ or ‘right’.

valign
¶ Vertical anchor position of the text field (str).
Either ‘top’, ‘baseline’ (default), ‘center’ or ‘bottom’
transform
: Transformation matrix system¶
This module provides 4x4 matrix operation and classes to handle them.

mat4LookAtDir
(position, direction, up)[source]¶ Creates matrix to look in direction from position.
Parameters:  position – Arraylike 3 coordinates of the point of view position.
 direction – Arraylike 3 coordinates of the sight direction vector.
 up – Arraylike 3 coordinates of the upward direction in the image plane.
Returns: Corresponding matrix.
Return type: numpy.ndarray of shape (4, 4)

mat4LookAt
(position, center, up)[source]¶ Creates matrix to look at center from position.
See gluLookAt.
Parameters:  position – Arraylike 3 coordinates of the point of view position.
 center – Arraylike 3 coordinates of the center of the scene.
 up – Arraylike 3 coordinates of the upward direction in the image plane.
Returns: Corresponding matrix.
Return type: numpy.ndarray of shape (4, 4)

mat4Frustum
(left, right, bottom, top, near, far)[source]¶ Creates a frustum projection matrix.
See glFrustum.

mat4Perspective
(fovy, width, height, near, far)[source]¶ Creates a perspective projection matrix.
Similar to gluPerspective.
Parameters:  fovy (float) – Field of view angle in degrees in the y direction.
 width (float) – Width of the viewport.
 height (float) – Height of the viewport.
 near (float) – Distance to the near plane (strictly positive).
 far (float) – Distance to the far plane (strictly positive).
Returns: Corresponding matrix.
Return type: numpy.ndarray of shape (4, 4)

mat4Orthographic
(left, right, bottom, top, near, far)[source]¶ Creates an orthographic (i.e., parallel) projection matrix.
See glOrtho.

mat4RotateFromAngleAxis
(angle, x=0.0, y=0.0, z=1.0)[source]¶ 4x4 rotation matrix from angle and axis.
Parameters:  angle (float) – The rotation angle in radians.
 x (float) – The rotation vector x coordinate.
 y (float) – The rotation vector y coordinate.
 z (float) – The rotation vector z coordinate.

mat4RotateFromQuaternion
(quaternion)[source]¶ 4x4 rotation matrix from quaternion.
Parameters: quaternion – Arraylike unit quaternion stored as (x, y, z, w)

mat4Shear
(axis, sx=0.0, sy=0.0, sz=0.0)[source]¶ 4x4 shear matrix: Skew two axes relative to a third fixed one.
shearFactor = tan(shearAngle)
Parameters:  axis (str) – The axis to keep constant and shear against. In ‘x’, ‘y’, ‘z’.
 sx (float) – The shear factor for the X axis relative to axis.
 sy (float) – The shear factor for the Y axis relative to axis.
 sz (float) – The shear factor for the Z axis relative to axis.

class
Transform
(static=False)[source]¶ 
inverse
()[source]¶ Return the Transform of the inverse.
The returned Transform is static, it is not updated when this Transform is modified.
Returns: A Transform which is the inverse of this Transform.

getMatrix
(copy=True)[source]¶ The 4x4 matrix of this transform.
Parameters: copy (bool) – True (the default) to get a copy of the matrix, False to get the internal matrix, do not modify! Returns: 4x4 matrix of this transform.

matrix
¶ The 4x4 matrix of this transform.

getInverseMatrix
(copy=False)[source]¶ The 4x4 matrix of the inverse of this transform.
Parameters: copy (bool) – True (the default) to get a copy of the matrix, False to get the internal matrix, do not modify! Returns: 4x4 matrix of the inverse of this transform.

inverseMatrix
¶ The 4x4 matrix of the inverse of this transform.

transformPoints
(points, direct=True, perspectiveDivide=False)[source]¶ Apply the transform to an array of points.
Parameters:  points – 2D array of N vectors of 3 or 4 coordinates
 direct (bool) – Whether to apply the direct (True, the default) or inverse (False) transform.
 perspectiveDivide (bool) – Whether to apply the perspective divide (True) or not (False, the default).
Returns: The transformed points.
Return type: numpy.ndarray of same shape as points.

transformPoint
(point, direct=True, perspectiveDivide=False)[source]¶ Apply the transform to a point.
Parameters:  point – Arraylike vector of 3 or 4 coordinates.
 direct (bool) – Whether to apply the direct (True, the default) or inverse (False) transform.
 perspectiveDivide (bool) – Whether to apply the perspective divide (True) or not (False, the default).
Returns: The transformed point.
Return type: numpy.ndarray of same length as point.

transformDir
(direction, direct=True)[source]¶ Apply the transform to a direction.
Parameters:  direction – Arraylike vector of 3 coordinates.
 direct (bool) – Whether to apply the direct (True, the default) or inverse (False) transform.
Returns: The transformed direction.
Return type: numpy.ndarray of length 3.

transformNormal
(normal, direct=True)[source]¶ Apply the transform to a normal: R = (M1)t * V.
Parameters:  normal – Arraylike vector of 3 coordinates.
 direct (bool) – Whether to apply the direct (True, the default) or inverse (False) transform.
Returns: The transformed normal.
Return type: numpy.ndarray of length 3.

transformBounds
(bounds, direct=True)[source]¶ Apply the transform to an axesaligned rectangular box.
Parameters:  bounds (2x3 numpy.ndarray) – Min and max coords of the box for each axes.
 direct (bool) – Whether to apply the direct (True, the default) or inverse (False) transform.
Returns: Axesaligned rectangular box including the transformed box.
Return type: 2x3 numpy.ndarray of float32


class
Inverse
(transform)[source]¶ Transform which is the inverse of another one.
Static: It never gets updated.

class
StaticTransformList
(iterable=())[source]¶ Transform that is a snapshot of a list of Transforms
It does not keep reference to the list of Transforms.
Parameters: iterable – Iterable of Transform used for initialization

class
Matrix
(matrix=None)[source]¶ 
setMatrix
(matrix=None)[source]¶ Update the 4x4 Matrix.
Parameters: matrix – 4x4 arraylike matrix or None for identity matrix.

matrix
¶ The 4x4 matrix of this transform.


class
Rotate
(angle=0.0, ax=0.0, ay=0.0, az=1.0)[source]¶ 
angle
¶ The rotation angle in degrees.

axis
¶ The normalized rotation axis as a numpy.ndarray.

setAngleAxis
(angle=None, axis=None)[source]¶ Update the angle and/or axis of the rotation.
Parameters:  angle (float) – The rotation angle in degrees.
 axis – Arraylike axis vector (3 coordinates).

quaternion
¶ Rotation unit quaternion as (x, y, z, w).
Where: (x, y, z) = sin(angle/2), w = cos(angle/2).


class
Shear
(axis, sx=0.0, sy=0.0, sz=0.0)[source]¶ 
axis
¶ The axis against which other axes are skewed.

factors
¶ The shear factors: shearFactor = tan(shearAngle)


class
Orthographic
(left=0.0, right=1.0, bottom=1.0, top=0.0, near=1.0, far=1.0, size=(1.0, 1.0), keepaspect=True)[source]¶ Orthographic (i.e., parallel) projection which can keep aspect ratio.
Clipping planes are adjusted to match the aspect ratio of the
size
attribute ifkeepaspect
is True.In this case, the left, right, bottom and top parameters defines the area which must always remain visible. Effective clipping planes are adjusted to keep the aspect ratio.
Parameters:  left (float) – Coord of the left clipping plane.
 right (float) – Coord of the right clipping plane.
 bottom (float) – Coord of the bottom clipping plane.
 top (float) – Coord of the top clipping plane.
 near (float) – Distance to the near plane.
 far (float) – Distance to the far plane.
 size (2tuple of float) – Viewport’s size used to compute the aspect ratio (width, height).
 keepaspect (bool) – True (default) to keep aspect ratio, False otherwise.

setClipping
(left=None, right=None, bottom=None, top=None)[source]¶ Set the clipping planes of the projection.
Parameters are adjusted to keep aspect ratio. If a clipping plane coord is not provided, it uses its current value
Parameters:  left (float) – Coord of the left clipping plane.
 right (float) – Coord of the right clipping plane.
 bottom (float) – Coord of the bottom clipping plane.
 top (float) – Coord of the top clipping plane.

left
¶ Coord of the left clipping plane.

right
¶ Coord of the right clipping plane.

bottom
¶ Coord of the bottom clipping plane.

top
¶ Coord of the top clipping plane.

size
¶ Viewport size as a 2tuple of float (width, height)

keepaspect
¶ True to keep aspect ratio, False otherwise.

class
Ortho2DWidget
(near=1.0, far=1.0, size=(1.0, 1.0))[source]¶ Orthographic projection with pixel as unit.
Provides same coordinates as widgets: origin: top left, X axis goes left, Y axis goes down.
Parameters:  near (float) – Z coordinate of the near clipping plane.
 far (float) – Z coordinante of the far clipping plane.
 size (2tuple of float) – Viewport’s size used to compute the aspect ratio (width, height).

class
Perspective
(fovy=90.0, near=0.1, far=1.0, size=(1.0, 1.0))[source]¶ Perspective projection matrix defined by FOV and aspect ratio.
Parameters:  fovy (float) – Vertical fieldofview in degrees.
 near (float) – The near clipping plane Z coord (stricly positive).
 far (float) – The far clipping plane Z coord (> near).
 size (2tuple of float) – Viewport’s size used to compute the aspect ratio (width, height).

fovy
¶ Vertical fieldofview in degrees.
utils
: Miscellaneous¶
This module provides functions to generate indices, to check intersection and to handle planes.

triangleToLineIndices
(triangleIndices, unicity=False)[source]¶ Generates lines indices from triangle indices.
This is generating lines indices for the edges of the triangles.
Parameters:  triangleIndices (numpy.ndarray) – The indices to draw a set of vertices as triangles.
 unicity (bool) – If True remove duplicated lines, else (the default) returns all lines.
Returns: The indices to draw the edges of the triangles as lines.
Return type: 1D numpy.ndarray of uint16 or uint32.

verticesNormalsToLines
(vertices, normals, scale=1.0)[source]¶ Return vertices of lines representing normals at given positions.
Parameters:  vertices (numpy.ndarray with shape: (nbPoints, 3)) – Positions of the points.
 normals (numpy.ndarray with shape: (nbPoints, 3)) – Corresponding normals at the points.
 scale (float) – The scale factor to apply to normals.
Returns: Array of vertices to draw corresponding lines.
Return type: numpy.ndarray with shape: (nbPoints * 2, 3)

unindexArrays
(mode, indices, *arrays)[source]¶ Convert indexed GL primitives to unindexed ones.
Given indices in arrays and the OpenGL primitive they represent, return the unindexed equivalent.
Parameters:  mode (str) – Kind of primitive represented by indices. In: points, lines, line_strip, loop, triangles, triangle_strip, fan.
 indices (numpy.ndarray of dimension 1.) – Indices in other arrays
 arrays – Remaining arguments are arrays to convert
Returns: Converted arrays
Return type: tuple of numpy.ndarray

triangleStripToTriangles
(strip)[source]¶ Convert a triangle strip to a set of triangles.
The order of the corners is inverted for odd triangles.
Parameters: strip (numpy.ndarray) – Array of triangle corners of shape (N, 3). N must be at least 3. Returns: Equivalent triangles corner as an array of shape (N, 3, 3) Return type: numpy.ndarray

trianglesNormal
(positions)[source]¶ Return normal for each triangle.
Parameters: positions (numpy.ndarray of shape (NbTriangles*3, 3)) – Serie of triangle’s corners Returns: Normals corresponding to each position. Return type: numpy.ndarray of shape (NbTriangles, 3)

gridVertices
(dim0Array, dim1Array, dtype)[source]¶ Generate an array of 2D positions from 2 arrays of 1D coordinates.
Parameters:  dim0Array – 1D arraylike of coordinates along the first dimension.
 dim1Array – 1D arraylike of coordinates along the second dimension.
 dtype (numpy.dtype) – Data type of the output array.
Returns: Array of grid coordinates.
Return type: numpy.ndarray with shape: (len(dim0Array), len(dim1Array), 2)

triangleStripGridIndices
(dim0, dim1)[source]¶ Generate indices to draw a grid of vertices as a triangle strip.
Vertices are expected to be stored as rowmajor (i.e., C contiguous).
Parameters:  dim0 (int) – The number of rows of vertices.
 dim1 (int) – The number of columns of vertices.
Returns: The vertex indices
Return type: 1D numpy.ndarray of uint32

linesGridIndices
(dim0, dim1)[source]¶ Generate indices to draw a grid of vertices as lines.
Vertices are expected to be stored as rowmajor (i.e., C contiguous).
Parameters:  dim0 (int) – The number of rows of vertices.
 dim1 (int) – The number of columns of vertices.
Returns: The vertex indices.
Return type: 1D numpy.ndarray of uint32

angleBetweenVectors
(refVector, vectors, norm=None)[source]¶ Return the angle between 2 vectors.
Parameters:  refVector (numpy.ndarray of shape: (NCoords,)) – Coordinates of the reference vector.
 vectors (numpy.ndarray of shape: (NCoords,) or (NbVector, NCoords)) – Coordinates of the vector(s) to get angle from reference.
 norm – A direction vector giving an orientation to the angles or None.
Returns: The angles in radians in [0, pi] if norm is None else in [0, 2pi].
Return type: float or numpy.ndarray of shape (NbVectors,)

segmentPlaneIntersect
(s0, s1, planeNorm, planePt)[source]¶ Compute the intersection of a segment with a plane.
Parameters:  s0 (1D numpy.ndarraylike of length 3) – First end of the segment
 s1 (1D numpy.ndarraylike of length 3) – Second end of the segment
 planeNorm (numpy.ndarray of shape: (3,)) – Normal vector of the plane.
 planePt (numpy.ndarray of shape: (3,)) – A point of the plane.
Returns: The intersection points. The number of points goes from 0 (no intersection) to 2 (segment in the plane)
Return type: list of numpy.ndarray

boxPlaneIntersect
(boxVertices, boxLineIndices, planeNorm, planePt)[source]¶ Return intersection points between a box and a plane.
Parameters:  boxVertices (numpy.ndarray with shape: (8, 3)) – Position of the corners of the box.
 boxLineIndices (numpy.ndarraylike with shape: (12, 2)) – Indices of the box edges.
 planeNorm (numpy.ndarray of shape: (3,)) – Normal vector of the plane.
 planePt (numpy.ndarray of shape: (3,)) – A point of the plane.
Returns: The found intersection points
Return type: numpy.ndarray with 2 dimensions

clipSegmentToBounds
(segment, bounds)[source]¶ Clip segment to volume aligned with axes.
Parameters:  segment (numpy.ndarray) – (p0, p1)
 bounds (numpy.ndarray) – (lower corner, upper corner)
Returns: Either clipped (p0, p1) or None if outside volume
Return type: Union[None,List[numpy.ndarray]]

segmentVolumeIntersect
(segment, nbins)[source]¶ Get bin indices intersecting with segment
It should work with N dimensions. Coordinate convention (z, y, x) or (x, y, z) should not matter as long as segment and nbins are consistent.
Parameters:  segment (numpy.ndarray) – Segment end points as a 2xN array of coordinates
 nbins (numpy.ndarray) – Shape of the volume with same coordinates order as segment
Returns: List of bins indices as a 2D array or None if no bins
Return type: Union[None,numpy.ndarray]

class
Plane
(point=(0.0, 0.0, 0.0), normal=(0.0, 0.0, 1.0))[source]¶ Object handling a plane and notifying plane changes.
Parameters:  point (3tuple of float.) – A point on the plane.
 normal (3tuple of float.) – Normal of the plane.

setPlane
(point=None, normal=None)[source]¶ Set plane point and normal and notify.
Parameters:  point (3tuple of float or None.) – A point on the plane.
 normal (3tuple of float or None.) – Normal of the plane.

point
¶ A point on the plane.

normal
¶ The (normalized) normal of the plane.

parameters
¶ Plane equation parameters: a*x + b*y + c*z + d = 0.

isPlane
¶ True if a plane is defined (i.e., normal != 0).

segmentIntersection
(s0, s1)[source]¶ Compute the plane intersection with segment [s0, s1].
Parameters:  s0 (1D numpy.ndarraylike of length 3) – First end of the segment
 s1 (1D numpy.ndarraylike of length 3) – Second end of the segment
Returns: The intersection points. The number of points goes from 0 (no intersection) to 2 (segment in the plane)
Return type: list of 1D numpy.ndarray
viewport
: Root of a scene tree¶
This module provides a class to control a viewport on the rendering window.
The Viewport
describes a Viewport rendering a scene.
The attribute scene
is the root group of the scene tree.
RenderContext
handles the current state during rendering.

class
RenderContext
(viewport, glContext)[source]¶ Handle a current rendering context.
An instance of this class is passed to rendering method through the scene during render.
User should NEVER use an instance of this class beyond the method it is passed to as an argument (i.e., do not keep a reference to it).
Parameters: 
cache
(key, factory, *args, **kwargs)[source]¶ Lazyloading cache to store values in the context for rendering
Parameters:  key – The key to retrieve
 factory – A callback taking args and kwargs as arguments and returning the value to store.
Returns: The stored or newly allocated value

viewport
¶ Viewport doing the current rendering

glCtx
¶ The OpenGL context in use

objectToCamera
¶ The current transform from object to camera coords.
Do not modify.

projection
¶ Projection transform.
Do not modify.

objectToNDC
¶ The transform from object to NDC (this includes projection).
Do not modify.

pushTransform
(transform_, multiply=True)[source]¶ Push a
Transform
on the transform stack.Parameters:  transform (Transform) – The transform to add to the stack.
 multiply (bool) – True (the default) to multiply with the top of the stack, False to push the transform as is without multiplication.

popTransform
()[source]¶ Pop the transform on top of the stack.
Returns: The Transform that is popped from the stack.

clipper
¶ The current clipping plane (ClippingPlane)

setClipPlane
(point=(0.0, 0.0, 0.0), normal=(0.0, 0.0, 0.0))[source]¶ Set the clipping plane to use
For now only handles a single clipping plane.
Parameters:  point (3tuple of float) – A point of the plane
 normal (3tuple of float) – Normal vector of the plane or (0, 0, 0) for no clipping

setupProgram
(program)[source]¶ Setsup uniforms of a program using the context shader functions.
Parameters: program (GLProgram) – The program to setup. It MUST be in use and using the context function.

fragDecl
¶ Fragment shader declaration for scene shader functions

fragCallPre
¶ Fragment shader call for scene shader functions (to do first)
It takes the camera position (vec4) as argument.

fragCallPost
¶ Fragment shader call for scene shader functions (to do last)
It takes the camera position (vec4) as argument.


class
Viewport
(framebuffer=0)[source]¶ Rendering a single scene through a camera in part of a framebuffer.
Parameters: framebuffer (int) – The framebuffer ID this viewport is rendering into 
transforms
¶ Proxy of camera transforms.
Do not modify the list.

dirty
¶ True if scene is dirty and needs redisplay.

background
¶ Viewport’s background color (4tuple of float in [0, 1] or None)
The background color is used to clear to viewport. If None, the viewport is not cleared

camera
¶ The camera used to render the scene.

light
¶ The light used to render the scene.

fog
¶ The fog function used to render the scene

origin
¶ Origin (ox, oy) of the viewport in pixels

size
¶ Size (width, height) of the viewport in pixels

shape
¶ Shape (height, width) of the viewport in pixels.
This is a convenient wrapper to the inverse of size.

framebuffer
¶ The framebuffer ID this viewport is rendering into (int)

render
(glContext)[source]¶ Perform the rendering of the viewport
Parameters: glContext (Context) – The context used for rendering

adjustCameraDepthExtent
()[source]¶ Update camera depth extent to fit the scene bounds.
Only near and far planes are updated. The scene might still not be fully visible (e.g., if spanning behind the viewpoint with perspective projection).

resetCamera
()[source]¶ Change camera to have the whole scene in the viewing frustum.
It updates the camera position and depth extent. Camera sight direction and up are not affected.

orbitCamera
(direction, angle=1.0)[source]¶ Rotate the camera around center of the scene.
Parameters:  direction (str) – Direction of movement relative to image plane. In: ‘up’, ‘down’, ‘left’, ‘right’.
 angle (float) – he angle in degrees of the rotation.

moveCamera
(direction, step=0.1)[source]¶ Move the camera relative to the image plane.
Parameters:  direction (str) – Direction relative to image plane. One of: ‘up’, ‘down’, ‘left’, ‘right’, ‘forward’, ‘backward’.
 step (float) – The ratio of data to step for each pan.

windowToNdc
(winX, winY, checkInside=True)[source]¶ Convert position from window to normalized device coordinates.
If window coordinates are int, they are moved half a pixel to be positioned at the center of pixel.
Parameters:  winX – X window coord, origin left.
 winY – Y window coord, origin top.
 checkInside (bool) – If True, returns None if position is outside viewport.
Returns: (x, y) Normalize device coordinates in [1, 1] or None. Origin center, x to the right, y goes upward.

ndcToWindow
(ndcX, ndcY, checkInside=True)[source]¶ Convert position from normalized device coordinates (NDC) to window.
Parameters:  ndcX (float) – X NDC coord.
 ndcY (float) – Y NDC coord.
 checkInside (bool) – If True, returns None if position is outside viewport.
Returns: (x, y) window coordinates or None. Origin topleft, x to the right, y goes downward.

window
: Onscreen window¶
This module provides a class for Viewports rendering on the screen.
The Window
renders a list of Viewports in the current framebuffer.
The rendering can be performed in an offscreen framebuffer that is only
updated when the scene has changed and not each time Qt is requiring a repaint.
The Context
and ContextGL2
represent the operating system
OpenGL context and handle OpenGL resources.

class
Context
(glContextHandle)[source]¶ Correspond to an operating system OpenGL context.
User should NEVER use an instance of this class beyond the method it is passed to as an argument (i.e., do not keep a reference to it).
Parameters: glContextHandle – System specific OpenGL context handle. 
isCurrent
¶ Whether this OpenGL context is the current one or not.

setCurrent
(isCurrent=True)[source]¶ Set the state of the OpenGL context to reflect OpenGL state.
This should not be called from the scene graph, only in the wrapper that handle the OpenGL context to reflect its state.
Parameters: isCurrent (bool) – The state of the system OpenGL context.

devicePixelRatio
¶ Ratio between device and device independent pixels (float)
This is useful for font rendering.

glContext
¶ The handle to the OpenGL context provided by the system.


class
ContextGL2
(glContextHandle)[source]¶ Handle a system GL2 context.
User should NEVER use an instance of this class beyond the method it is passed to as an argument (i.e., do not keep a reference to it).
Parameters: glContextHandle – System specific OpenGL context handle. 
prog
(vertexShaderSrc, fragmentShaderSrc, attrib0='position')[source]¶ Cache program within context.
WARNING: No cleanup.
Parameters:  vertexShaderSrc (str) – Vertex shader source code
 fragmentShaderSrc (str) – Fragment shader source code
 attrib0 (str) – Attribute’s name to bind to position 0 (default: ‘position’). On some platform, this attribute MUST be active and with an array attached to it in order for the rendering to occur….

makeVbo
(data=None, sizeInBytes=None, usage=None, target=None)[source]¶ Create a VBO in this context with the data.
Current limitations:
 One array per VBO
 Do not support sharing VertexBuffer across VboAttrib
Automatically discards the VBO when the returned
VertexBuffer
istance is deleted.Parameters:  data (numpy.ndarray) – 2D array of data to store in VBO or None.
 sizeInBytes (int) – Size of the VBO or None. It should be <= data.nbytes if both are given.
 usage – OpenGL usage define in VertexBuffer._USAGES.
 target – OpenGL target in VertexBuffer._TARGETS.
Returns: The VertexBuffer created in this context.

makeVboAttrib
(data, usage=None, target=None)[source]¶ Create a VBO from data and returns the associated VBOAttrib.
Automatically discards the VBO when the returned
VBOAttrib
istance is deleted.Parameters:  data (numpy.ndarray) – 2D array of data to store in VBO or None.
 usage – OpenGL usage define in VertexBuffer._USAGES.
 target – OpenGL target in VertexBuffer._TARGETS.
Returns: A VBOAttrib instance created in this context.


class
Window
(mode='framebuffer')[source]¶ OpenGL Framebuffer where to render viewports
Parameters: mode (str) – Rendering mode to use:
 ’direct’ to render everything for each render call
 ’framebuffer’ to cache viewport rendering in a texture and update the texture only when needed.

dirty
¶ True if this object or any attached viewports is dirty.

size
¶ Size (width, height) of the window in pixels

shape
¶ Shape (height, width) of the window in pixels.
This is a convenient wrapper to the reverse of size.

viewports
¶ List of viewports to render in the corresponding framebuffer

framebufferid
¶ Framebuffer ID used to perform rendering