[WIP] new shrinking #23
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,191 @@ | ||
| module CompressUDG | ||
| using Graphs | ||
|
|
||
| export UNode, contract_graph, CompressUDGMethod | ||
|
|
||
| struct UNode | ||
| vertex::Int # vertex index in original graph | ||
| pos::Tuple{Int, Int} | ||
| neighbors::Vector{Int} | ||
| end | ||
| function Base.:(==)(x::UNode, y::UNode) | ||
| x.vertex == y.vertex && x.neighbors == y.neighbors | ||
| end | ||
|
|
||
| # get surrounding neighbor points on UDG | ||
| function get_udg_neighbors(pos::Tuple{Int, Int}) | ||
| p_x, p_y = pos | ||
| pos_udg_neighbors = Vector{Tuple{Int, Int}}() | ||
|
|
||
| for i = -1:1, j = -1:1 | ||
| !(i == 0 && j == 0) && push!(pos_udg_neighbors, (p_x + i, p_y + j)) | ||
| end | ||
| return pos_udg_neighbors | ||
| end | ||
|
|
||
|
|
||
| # find UDNode given a position; return nothing if no node at that position | ||
| function get_UNode_from_pos(pos::Tuple{Int, Int}, node_list::Vector{UNode}) | ||
| for u in node_list | ||
| (u.pos == pos) && return u | ||
| end | ||
| return nothing | ||
| end | ||
|
|
||
| # find boundaries of grid graph given list of UNodes | ||
| function find_boundaries(node_list::Vector{UNode}) | ||
| min_x = typemax(Int) | ||
| min_y = typemax(Int) | ||
| max_x = 0 | ||
| max_y = 0 | ||
|
|
||
| for u in node_list | ||
| p_x, p_y = u.pos | ||
| (p_x > max_x) && (max_x = p_x) | ||
| (p_x < min_x) && (min_x = p_x) | ||
| (p_y > max_y) && (max_y = p_y) | ||
| (p_y < min_y) && (min_y = p_y) | ||
| end | ||
| return min_x, min_y, max_x, max_y | ||
| end | ||
|
|
||
| # find points on the boundary that can be moved | ||
| function find_boundary_points(node_list::Vector{UNode}, x_min, x_max, y_min, y_max) | ||
| pts_boundary = Vector{UNode}() | ||
|
|
||
| for u in node_list | ||
| p_x, p_y = u.pos | ||
| (p_x == x_min || p_x == x_max || p_y == y_min || p_y == y_max) && push!(pts_boundary, u) | ||
| end | ||
|
|
||
| return pts_boundary | ||
| end | ||
|
|
||
|
|
||
| # check that the new position of node n satisfies UDG requirements | ||
| function check_UDG_criteria(n::UNode, new_pos::Tuple{Int, Int}, | ||
| node_list::Vector{UNode}) | ||
| # check if new_pos is already occupied | ||
| (get_UNode_from_pos(new_pos, node_list) != nothing) && return false | ||
|
|
||
| p_x, p_y = new_pos | ||
| new_neighbors = Vector{Int}() | ||
|
|
||
| for p in get_udg_neighbors(new_pos) | ||
| unode = get_UNode_from_pos(p, node_list) | ||
|
|
||
| if (unode !== nothing) && (unode.vertex != n.vertex) | ||
| push!(new_neighbors, unode.vertex) | ||
| end | ||
| end | ||
|
|
||
| (issetequal(new_neighbors, n.neighbors) == true) && return true | ||
| return false | ||
| end | ||
|
|
||
| # move node n to a new position new_pos | ||
| function move_node(n::UNode, node_list::Vector{UNode}, candidates::Vector{Tuple{Int, Int}}) | ||
| for p in candidates | ||
| if check_UDG_criteria(n, p, node_list) | ||
| node_list[n.vertex] = UNode(n.vertex, p, n.neighbors) | ||
| return node_list | ||
| end | ||
| end | ||
| return node_list | ||
| end | ||
|
|
||
| # determine candidates to move | ||
| function determine_candidates(pos::Tuple{Int, Int}, x_min, x_max, y_min, y_max) | ||
| p_x, p_y = pos | ||
|
|
||
| halfx = (x_max - x_min)/2 + x_min | ||
| halfy = (y_max - y_min)/2 + y_min | ||
|
|
||
| # move boundary vertices such that we can shrink graph from four quadrants | ||
|
There was a problem hiding this comment. Good! Now it is much easier to read. If possible, you should try to lessen the number of branches - otherwise you need to write tests for every branch to ensure the test coverage is good. |
||
| (p_x == x_min && p_y >= halfy) && return [(p_x + 1, p_y), (p_x + 1, p_y - 1), (p_x, p_y - 1)] | ||
| (p_x == x_min && p_y < halfy) && return [(p_x + 1, p_y), (p_x + 1, p_y + 1), (p_x, p_y + 1)] | ||
| (p_x == x_max && p_y >= halfy) && return [(p_x - 1, p_y), (p_x - 1, p_y - 1), (p_x, p_y - 1)] | ||
| (p_x == x_max && p_y < halfy) && return [(p_x - 1, p_y), (p_x - 1, p_y + 1), (p_x, p_y + 1)] | ||
|
|
||
| (p_x < halfx && p_y == y_min) && return [(p_x, p_y + 1), (p_x + 1, p_y + 1), (p_x + 1, p_y)] | ||
| (p_x >= halfx && p_y == y_min) && return [(p_x, p_y + 1), (p_x - 1, p_y + 1), (p_x - 1, p_y)] | ||
| (p_x < halfx && p_y == y_max) && return [(p_x, p_y - 1), (p_x + 1, p_y - 1), (p_x + 1, p_y)] | ||
| (p_x >= halfx && p_y == y_max) && return [(p_x, p_y - 1), (p_x - 1, p_y - 1), (p_x - 1, p_y)] | ||
|
|
||
| end | ||
|
|
||
|
|
||
| # one shrinking step | ||
| function greedy_step(node_list::Vector{UNode}, min_x::Int, max_x::Int, | ||
| min_y::Int, max_y::Int) | ||
|
|
||
| boundary_pts = find_boundary_points(node_list, min_x, max_x, | ||
| min_y, max_y) | ||
|
|
||
| for p in boundary_pts | ||
| node_list = move_node(p, node_list, determine_candidates(p.pos, min_x, max_x, | ||
| min_y, max_y)) | ||
| end | ||
|
|
||
| return node_list | ||
| end | ||
|
|
||
| function unitdisk_graph(locs::AbstractVector, unit::Real) | ||
minhthin1028 marked this conversation as resolved.
Show resolved
Hide resolved
|
||
| n = length(locs) | ||
| g = SimpleGraph(n) | ||
| for i=1:n, j=i+1:n | ||
| if sum(abs2, locs[i] .- locs[j]) < unit ^ 2 | ||
| add_edge!(g, i, j) | ||
| end | ||
| end | ||
| return g | ||
| end | ||
|
|
||
| # interfaces | ||
| abstract type CompressUDGMethod end | ||
|
|
||
| """ | ||
| contract_graph(locs::Vector{Tuple{Int, Int}}) | ||
| Compute a contracted version of input graph node positions and returns a | ||
| corresponding layout of new condensed graph | ||
| """ | ||
| function contract_graph(node_positions::Vector{Tuple{Int, Int}}) | ||
| # initiate UNodes | ||
|
|
||
| n_list = Vector{UNode}(undef, size(node_positions)[1]) | ||
| g = unitdisk_graph(node_positions, 1.5) | ||
|
|
||
| for (ind, n_pos) in enumerate(node_positions) | ||
| n_list[ind] = UNode(ind, n_pos, neighbors(g, ind)) | ||
| end | ||
|
|
||
| xmin, ymin, xmax, ymax = find_boundaries(n_list) | ||
|
|
||
|
|
||
| while (xmax - xmin > 1) && (ymax - ymin > 1) | ||
| n_list = greedy_step(n_list, xmin, xmax, ymin, ymax) | ||
|
|
||
| if xmin < xmax | ||
| xmin += 1 | ||
| xmax -= 1 | ||
| end | ||
|
|
||
| if ymin < ymax | ||
| ymin += 1 | ||
| ymax -= 1 | ||
| end | ||
|
|
||
| end | ||
|
|
||
| locs_new = Vector{Tuple{Int, Int}}(undef, size(node_positions)[1]) | ||
| for (ind, un) in enumerate(n_list) | ||
| locs_new[ind] = un.pos | ||
| end | ||
|
|
||
| return locs_new | ||
| end | ||
|
|
||
| end | ||
|
|
||
| using .CompressUDG | ||
| export UNode, contract_graph, CompressUDGMethod | ||
Oops, something went wrong.
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
There was a problem hiding this comment.
Choose a reason for hiding this comment
The reason will be displayed to describe this comment to others. Learn more.
Wanted an estimate of overhead scaling, can delete/modify function