AP_GeodesicGrid::neighbor_umbrella Struct Reference

Public Attributes
uint8_t	components [5]
uint8_t	v0_c0
uint8_t	v1_c1
uint8_t	v2_c1
uint8_t	v4_c4
uint8_t	v0_c4

Detailed Description

The representation of the neighbor umbrellas of T_0.

The values for the neighbors of T_10 can be derived from the values for T_0. How to find the correct values is explained on each member.

Let T_0 = (a, b, c). Thus, 6 indexes can be used for this data structure, so that:

• index 0 represents the neighbor of T_0 with respect to (a, b).
• index 1 represents the neighbor of T_0 with respect to (b, c).
• index 2 represents the neighbor of T_0 with respect to (c, a).
• index 3 represents the neighbor of T_10 with respect to (-a, -b).
• index 4 represents the neighbor of T_10 with respect to (-b, -c).
• index 5 represents the neighbor of T_10 with respect to (-c, -a).

Those indexes are mapped to this array with index % 3.

The edges are represented with pairs because the order of the vertices matters to the order the triangles' indexes are defined - the order of the umbrellas' vertices and components is convertioned to be with respect to those pairs.

Definition at line 203 of file AP_GeodesicGrid.h.

Member Data Documentation

components

uint8_t AP_GeodesicGrid::neighbor_umbrella::components[5]

The umbrella's components. The value of components[i] is the icosahedron triangle index of the i-th component.

In order to find the components for T_10, the following just finding the index of the opposite triangle is enough. In other words, (components[i] + 10) % 20.

Definition at line 212 of file AP_GeodesicGrid.h.

Referenced by AP_GeodesicGrid::_neighbor_umbrella_component().

v0_c0

uint8_t AP_GeodesicGrid::neighbor_umbrella::v0_c0

The fields with name in the format vi_cj are interpreted as the following: vi_cj is the index of the vector, in the icosahedron triangle pointed by components[j], that matches the umbrella's i-th vertex.

The values don't change for T_10.

Definition at line 221 of file AP_GeodesicGrid.h.

Referenced by AP_GeodesicGrid::_from_neighbor_umbrella().

v0_c4

uint8_t AP_GeodesicGrid::neighbor_umbrella::v0_c4

Definition at line 225 of file AP_GeodesicGrid.h.

v1_c1

uint8_t AP_GeodesicGrid::neighbor_umbrella::v1_c1

Definition at line 222 of file AP_GeodesicGrid.h.

Referenced by AP_GeodesicGrid::_from_neighbor_umbrella().

v2_c1

uint8_t AP_GeodesicGrid::neighbor_umbrella::v2_c1

Definition at line 223 of file AP_GeodesicGrid.h.

v4_c4

uint8_t AP_GeodesicGrid::neighbor_umbrella::v4_c4

Definition at line 224 of file AP_GeodesicGrid.h.

Referenced by AP_GeodesicGrid::_from_neighbor_umbrella().

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The documentation for this struct was generated from the following file:

• libraries/AP_Math/AP_GeodesicGrid.h