raytools.mapper

Mapper

class raytools.mapper.Mapper(dxyz=(0.0, 0.0, 1.0), sf=(1, 1), bbox=((0, 0), (1, 1)), aspect=None, name='mapper', origin=(0, 0, 0), jitterrate=1.0, uvz=0.0)

Bases: object

translate between world and normalized UV space. do not use directly, instead use an inheriting class.

Parameters:

• sf (tuple np.array, optional) – scale factor for each axis (array of length(2)

• bbox (tuple np.array, optional) – bounding box for mapper shape (2, 2)

• name (str, optional) – used for output file naming

property aspect

property dxyz

(float, float, float) central view direction

property bbox

bounding box of view

Type:

np.array of shape (2,2)

view2world(xyz)

rotate vectors from view direction to world Z

world2view(xyz)

rotate vectors from world Z to view direction

xyz2uv(xyz)

transform from world xyz space to mapper UV space

uv2xyz(uv, stackorigin=False)

transform from mapper UV space to world xyz

idx2uv(idx, shape, jitter=True)

Parameters:

• idx (flattened index)

• shape – the shape to unravel into

• jitter (bool, optional) – randomly offset coordinates within grid

Returns:

uv – uv coordinates

Return type:

np.array

static uv2idx(uv, shape)

xyz2vxy(xyz)

transform from world xyz to view image space (2d)

vxy2xyz(xy, stackorigin=False)

transform from view image space (2d) to world xyz

framesize(res)

pixels(res, jitter=0.0)

generate pixel coordinates for image space

pixelrays(res, jitter=0.0)

world xyz coordinates for pixels in view image space

ray2pixel(xyz, res, integer=True)

world xyz to pixel coordinate

pixel2ray(pxy, res)

pixel coordinate to world xyz vector

pixel2omega(pxy, res)

pixel area

in_view(vec, indices=True)

generate mask for vec that are in the field of view

header(**kwargs)

init_img(res=512, jitter=0.0, **kwargs)

Initialize an image array with vectors and mask

Parameters:

• res (int, optional) – image array resolution

• jitter (float, optional) – pixel jitter rate

• kwargs – passed to self.header

Returns:

• img (np.array) – zero array of shape (res, res)

• vecs (np.array) – direction vectors corresponding to each pixel (img.size, 3)

• mask (np.array) – indices of flattened img that are in view

• mask2 (np.array None) –

  if ViewMapper has inverse, mask for opposite view, usage:

  add_to_img(img, vecs[mask], mask)
  add_to_img(img[res:], vecs[res:][mask2], mask2
  

• header (str)

add_vecs_to_img(img, v, channels=(1, 0, 0), grow=0, **kwargs)

plot(xyz, outf, res=1000, grow=1, **kwargs)

AngularMixin

class raytools.mapper.angularmixin.AngularMixin

Bases: object

includes overrides of transformation functions for angular type mapper classes. Inherit before raytools.mapper.Mapper eg:

NewMapper(AngularMixin, Mapper)

initialization of NewMapper must include declarations of:

self._viewangle = viewangle
self._chordfactor = chordfactor
self._ivm = ivm

xyz2uv(xyz)

transform from world xyz space to mapper UV space

uv2xyz(uv, stackorigin=False)

transform from mapper UV space to world xyz

xyz2vxy(xyz)

transform from world xyz to view image space (2d)

vxy2xyz(xy, stackorigin=False)

transform from view image space (2d) to world xyz

static framesize(res)

pixelrays(res)

world xyz coordinates for pixels in view image space

pixel2omega(pxy, res)

pixel solid angle

in_view(vec, indices=True, tol=0.0)

generate mask for vec that are in the field of view (up to 180 degrees) if view aspect is 2, only tests against primary view direction

header(pt=(0, 0, 0), viewproj='vta', **kwargs)

init_img(res=512, pt=(0, 0, 0), features=1, viewproj='vta', indices=True, **kwargs)

Initialize an image array with vectors and mask

Parameters:

• res (int, optional) – image array resolution

• pt (tuple, optional) – view point for image header

• features (int, optional) – when greater than 1 initialize img array with N output channels

• viewproj (str, optional) –

  output view projection chose from:

  angular: '[Aa]*', 'vta', 'fish*'
  shirley chiu: '[Uu]*', 'square'
  

Returns:

• img (np.array) – zero array of shape (res*self.aspect, res)

• vecs (np.array) – direction vectors corresponding to each pixel (img.size, 3)

• mask (np.array) – indices of flattened img that are in view

• mask2 (np.array None) – if features > 1, use mask 2 fro color images

• header (str)

add_vecs_to_img(img, v, channels=(1, 0, 0), grow=0, fisheye=True, mask=None)

property viewangle

view angle

property ivm

viewmapper for opposite view direction (in case of 360 degree view

ctheta(vec)

cos(theta) (dot product) between view direction and vec

radians(vec)

angle in radians betweeen view direction and vec

degrees(vec)

angle in degrees betweeen view direction and vec

ViewMapper

class raytools.mapper.ViewMapper(dxyz=(0.0, 1.0, 0.0), viewangle=360.0, name='view', origin=(0, 0, 0), jitterrate=0.5)

Bases: AngularMixin, Mapper

translate between world direction vectors and normalized UV space for a given view angle. pixel projection yields equiangular projection

Parameters:

• dxyz (tuple, optional) – central view direction

• viewangle (float, optional) – if < 180, the horizontal and vertical view angle, if greater, view becomes 360,180

property aspect

property dxyz

(float, float, float) central view direction

idx2uv(idx, shape, jitter=True)

Parameters:

• idx (flattened index)

• shape – the shape to unravel into

• jitter (bool, optional) – randomly offset coordinates within grid

Returns:

uv – uv coordinates

Return type:

np.array

transform_to(imarray, other, nearest=False)

take an image arrray with an assumed projection of self and transform it to other

Parameters:

• imarray (np.array) – 2-d or 3-d array with (features,x,y)

• other (raytools.ViewMapper) – the destination view

• nearest (bool) – disable linear interpolation and use nearest pixel sets the method= of scipy.interpolate.RegularGridInterpolator

Return type:

np.array