fresnel.geometry¶

Overview

`fresnel.geometry.Geometry`	Base class for all geometry.
`fresnel.geometry.ConvexPolyhedron`	Convex polyhedron geometry.
`fresnel.geometry.Cylinder`	Cylinder geometry.
`fresnel.geometry.Box`	Box geometry.
`fresnel.geometry.Polygon`	Polygon geometry.
`fresnel.geometry.Sphere`	Sphere geometry.

Details

Geometric primitives.

Geometry provides operations common to all geometry classes. Use a specific geometry class to add objects to the fresnel.Scene.

See also

Tutorials:

class fresnel.geometry.Box(scene, box, box_radius=0.5, box_color=[0, 0, 0])¶

Box geometry.

Generate a triclinic box shape.

Parameters

scene (fresnel.Scene) – Add the geometry to this scene
box_radius (numpy.ndarray or array_like) – (`1`, `3`, or `6` : float32) Assumes 1x1 is cubic, 1x3 is orthorhombic, and 1x6 is triclinic.
radius (float) – Radius of box edges.
box_color (numpy.ndarray or array_like) – (1x3 : float32) - Color of box edges.

See also

Tutorials:

Note

The constructor arguments radius and color are optional. If you do not provide them, they are initialized to 0.5 and black, respectively.

Note

The Box class is constructed from Cylinders, which can be modified individually. The convenience attributes box_radius and box_color can be used to easily modify the thickness and color of the box. If the individual cylinders are modified, the getter for the box_radius will return the radius of the 0th element cylinder.

points¶

Read or modify the start and end points of the cylinders.

Type: fresnel.util.Array

radius¶

Read or modify the radii of the cylinders.

Type: fresnel.util.Array

color¶

Read or modify the colors of the start and end points of the cylinders.

Type: fresnel.util.Array

box¶

Read or modify the box parameters. Boxes will be converted from any acceptable box type to a tuple (Lx, Ly, Lz, xy, xz, yz). Changing the box will update the points used to generate the cylinders.

Type: tuple

box_radius¶

Read or modify the radii of all the cylinders.

Type: float

box_color¶

Read or modify the color of the box material.

Type: tuple

class fresnel.geometry.ConvexPolyhedron(scene, polyhedron_info, position=None, orientation=None, color=None, N=None, material=<fresnel.material.Material object>, outline_material=<fresnel.material.Material object>, outline_width=0.0)¶

Convex polyhedron geometry.

Define a set of convex polyhedron primitives. A convex polyhedron is defined by P outward facing planes (origin and normal vector) and a radius that encompass the shape. fresnel.util.convex_polyhedron_from_vertices() can construct this by computing the convex hull of a set of vertices.

Parameters

scene (fresnel.Scene) – Add the geometry to this scene
polyhedron_info (dict) – A dictionary containing the face normals (face_normal), origins (face_origin), colors (face_color), and the radius (radius)).
position (numpy.ndarray or array_like) – (Nx3 : float32) - Position of each polyhedra.
orientation (numpy.ndarray or array_like) – (Nx4 : float32) - Orientation of each polyhedra (as a quaternion).
color (numpy.ndarray or array_like) – (Nx3 : float32) - Color of each polyhedron.
N (int) – Number of spheres in the geometry. If None, determine N from position.

See also

Tutorials:

Convex polyhedron

Note

The constructor arguments position, orientation, and color are optional. If you do not provide them, they are initialized to 0’s.

Hint

Avoid costly memory allocations and type conversions by specifying primitive properties in the appropriate numpy array type.

position¶

Read or modify the positions of the polyhedra.

Type: fresnel.util.Array

orientation¶

Read or modify the orientations of the polyhedra.

Type: fresnel.util.Array

color¶

Read or modify the color of the polyhedra.

Type: fresnel.util.Array

color_by_face¶

Set to 0 to color particles by the per-particle color. Set to 1 to color faces by the per-face color. Set to a value between 0 and 1 to blend per-particle and per-face colors.

Type: float

get_extents()¶

Get the extents of the geometry

Returns: [[minimum x, minimum y, minimum z], [maximum x, maximum y, maximum z]]

class fresnel.geometry.Cylinder(scene, points=None, radius=None, color=None, N=None, material=<fresnel.material.Material object>, outline_material=<fresnel.material.Material object>, outline_width=0.0)¶

Cylinder geometry.

Define a set of spherocylinder primitives with start and end positions, radii, and individual colors.

Parameters

scene (fresnel.Scene) – Add the geometry to this scene
points (numpy.ndarray or array_like) – (Nx2x3 : float32) - cylinder start and end points.
radius (numpy.ndarray or array_like) – (N : float32) - Radius of each cylinder.
color (numpy.ndarray or array_like) – (Nx2x3 : float32) - Color of each start and end point.
N (int) – Number of cylinders in the geometry. If None, determine N from points.

See also

Tutorials:

Cylinder

Note

The constructor arguments points, radius, and color are optional. If you do not provide them, they are initialized to 0’s.

Hint

Avoid costly memory allocations and type conversions by specifying primitive properties in the appropriate numpy array type.

Tip

When all cylinders are the same size, pass a single value for radius and numpy will broadcast it to all elements of the array.

points¶

Read or modify the start and end points of the cylinders.

Type: fresnel.util.Array

radius¶

Read or modify the radii of the cylinders.

Type: fresnel.util.Array

color¶

Read or modify the colors of the start and end points of the cylinders.

Type: fresnel.util.Array

get_extents()¶

Get the extents of the geometry

Returns: [[minimum x, minimum y, minimum z], [maximum x, maximum y, maximum z]]

class fresnel.geometry.Geometry¶

Base class for all geometry.

Geometry provides operations common to all geometry classes.

material¶

The geometry’s material.

Type: fresnel.material.Material

outline_material¶

The geometry’s outline material.

Type: fresnel.material.Material

outline_width¶

The geometry’s outline width, in distance units in the scene’s coordinate system.

Type: float

Note

You cannot instantiate a Geometry directly. Use one of the sub classes.

disable()¶

Disable the geometry.

When disabled, the geometry will not be present in the scene.

enable()¶

Enable the geometry.

When enabled, the geometry will be present when rendering the scene.

remove()¶

Remove the geometry from the scene.

After calling remove, the geometry is no longer part of the scene. It cannot be added back into the scene. Use disable() if you want a reversible operation.

class fresnel.geometry.Mesh(scene, vertices, position=None, orientation=None, color=None, N=None, material=<fresnel.material.Material object>, outline_material=<fresnel.material.Material object>, outline_width=0.0)¶

Mesh geometry.

Define a set of triangle mesh primitives.

Parameters

scene (fresnel.Scene) – Add the geometry to this scene
vertices (numpy.ndarray or array_like) – (3Tx3 : float32) - Vertices of the triangles, listed contiguously. Vertices 0,1,2 define the first triangle, 3,4,5 define the second, and so on.
color (numpy.ndarray or array_like) – (3Tx3 : float32) - Color of each vertex.
position (numpy.ndarray or array_like) – (Nx3 : float32) - Positions of each mesh instance.
orientation (numpy.ndarray or array_like) – (Nx4 : float32) - Orientation of each mesh instance (as a quaternion).
N (int) – Number of mesh instances in the geometry. If None, determine N from position.

See also

Tutorials:

Mesh

Note

The constructor arguments position, orientation, and color are optional, and just short-hand for assigning the attribute after construction.

Colors are in the linearized sRGB color space. Use fresnel.color.linear() to convert standard sRGB colors into this space. Mesh determines the color of a triangle using interpolation with the barycentric coordinates in every triangular face.

Hint

Avoid costly memory allocations and type conversions by specifying primitive properties in the appropriate numpy array type.

position¶

Read or modify the positions of the mesh instances.

Type: fresnel.util.Array

orientation¶

Read or modify the orientations of the mesh instances.

Type: fresnel.util.Array

color¶

Read or modify the color of the vertices.

Type: fresnel.util.Array

get_extents()¶

Get the extents of the geometry

Returns: [[minimum x, minimum y, minimum z], [maximum x, maximum y, maximum z]]

class fresnel.geometry.Polygon(scene, vertices, position=None, angle=None, color=None, rounding_radius=0, N=None, material=<fresnel.material.Material object>, outline_material=<fresnel.material.Material object>, outline_width=0.0)¶

Polygon geometry.

Define a set of simple polygon primitives. Each polygon face is always in the xy plane. Each polygon may have a different color and rotation angle.

Parameters

scene (fresnel.Scene) – Add the geometry to this scene
vertices (numpy.ndarray or array_like) – (Nx2 : float32) - Polygon vertices.
position (numpy.ndarray or array_like) – (Nx2 : float32) - Position of each polygon.
angle (numpy.ndarray or array_like) – (N : float32) - Orientation angle of each polygon.
color (numpy.ndarray or array_like) – (Nx3 : float32) - Color of each polygon.
rounding_radius (float) – Rounding radius for spheropolygons.
N (int) – Number of polygons in the geometry. If None, determine N from position.

See also

Tutorials:

Polygon

Note

The constructor arguments position, angle, and color are optional. If you do not provide them, they are initialized to 0’s.

Hint

Avoid costly memory allocations and type conversions by specifying primitive properties in the appropriate numpy array type.

position¶

Read or modify the positions of the polygons.

Type: fresnel.util.Array

angle¶

Read or modify the orientation angles of the polygons.

Type: fresnel.util.Array

color¶

Read or modify the colors of the polygons.

Type: fresnel.util.Array

get_extents()¶

Get the extents of the geometry

Returns: [[minimum x, minimum y, minimum z], [maximum x, maximum y, maximum z]]

class fresnel.geometry.Sphere(scene, position=None, radius=None, color=None, N=None, material=<fresnel.material.Material object>, outline_material=<fresnel.material.Material object>, outline_width=0.0)¶

Sphere geometry.

Define a set of sphere primitives with positions, radii, and individual colors.

Parameters

scene (fresnel.Scene) – Add the geometry to this scene
position (numpy.ndarray or array_like) – (Nx3 : float32) - Position of each sphere.
radius (numpy.ndarray or array_like) – (N : float32) - Radius of each sphere.
color (numpy.ndarray or array_like) – (Nx3 : float32) - Color of each sphere.
N (int) – Number of spheres in the geometry. If None, determine N from position.

See also

Tutorials:

Sphere

Note

The constructor arguments position, radius, and color are optional. If you do not provide them, they are initialized to 0’s.

Hint

Avoid costly memory allocations and type conversions by specifying primitive properties in the appropriate numpy array type.

Tip

When all spheres are the same size, pass a single value for radius and numpy will broadcast it to all elements of the array.

position¶

Read or modify the positions of the spheres.

Type: fresnel.util.Array

radius¶

Read or modify the radii of the spheres.

Type: fresnel.util.Array

color¶

Read or modify the color of the spheres.

Type: fresnel.util.Array

get_extents()¶

Get the extents of the geometry

Returns: [[minimum x, minimum y, minimum z], [maximum x, maximum y, maximum z]]