tTightening criterion for cell mapping to ensure no overlaps - Granular.jl - Julia package for granular dynamics simulation
(HTM) git clone git://src.adamsgaard.dk/Granular.jl
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---
(DIR) commit 6ccf07e651d07718aa2129c1cbb56dc4975b5e45
(DIR) parent bcc9daa32ee17a31b2576133f546cb19890c539e
(HTM) Author: Anders Damsgaard <andersd@riseup.net>
Date: Wed, 24 Jan 2018 11:45:50 -0500
Tightening criterion for cell mapping to ensure no overlaps
Diffstat:
M src/packing.jl | 55 ++++++++++++++++++++++++++++++-
M test/packing.jl | 35 +++++++++++++++++++------------
2 files changed, 76 insertions(+), 14 deletions(-)
---
(DIR) diff --git a/src/packing.jl b/src/packing.jl
t@@ -308,6 +308,58 @@ function irregularPacking!(simulation::Simulation;
end
end
+export rasterPacking!
+function rasterPacking!(sim::Simulation,
+ r_min::Real,
+ r_max::Real;
+ padding_factor::Real=0.1,
+ size_distribution::String="powerlaw",
+ size_distribution_parameter::Real=-1.8,
+ seed::Integer=1,
+ verbose::Bool=true)
+
+ r_rand = 0.
+ const h = .5 # disc tickness
+ const dx = r_max * 2. * (1. + padding_factor) # cell size
+ const dx_padding = r_max * 2. * padding_factor
+ srand(seed)
+
+ const np_init = length(sim.grains)
+
+ # Generate a grid spanning the entire domain, with cell width corresponding
+ # to the largest grain to be inserted
+ const occupied = rasterMap(sim, dx)
+
+ # Add grains in unoccupied places
+ pos = zeros(2)
+ for ix=1:size(occupied, 1)
+ for iy=1:size(occupied, 2)
+
+ if occupied[ix,iy]
+ continue
+ end
+
+ if size_distribution == "powerlaw"
+ r_rand = Granular.randpower(1, size_distribution_parameter,
+ r_min, r_max)
+ elseif size_distribution == "uniform"
+ r_rand = rand()*(r_max - r_min) + r_min
+ end
+
+ # Determine position from grid index and sample randomly from within
+ # padding
+ pos = [ix*dx - .5*dx, iy*dx - .5*dx] .+
+ rand(2) .* dx_padding .- .5*dx_padding
+
+ addGrainCylindrical!(sim, pos, r_rand, h, verbose=false)
+
+ end
+ end
+ if verbose
+ info("Generated $(length(sim.grains) - np_init) points")
+ end
+end
+
"""
rasterMap(sim, dx)
t@@ -347,6 +399,7 @@ function rasterMap(sim::Simulation, dx::Real)
min_i = 0; min_j = 0
max_i = 0; max_j = 0
cell_mid_point = zeros(2)
+ const dist = sqrt(2.0*(dx/2.0)^2.)
for grain in sim.grains
# Find center position in `occupied` grid
t@@ -364,7 +417,7 @@ function rasterMap(sim::Simulation, dx::Real)
cell_mid_point = dx .* Vector{Float64}([i,j]) - 0.5 * dx
if (norm(cell_mid_point - grain.lin_pos) -
- grain.contact_radius < 0.5*dx)
+ grain.contact_radius < dist)
occupied[i,j] = true
end
end
(DIR) diff --git a/test/packing.jl b/test/packing.jl
t@@ -84,7 +84,7 @@ Granular.irregularPacking!(sim,
@test length(sim.grains) > 280
-info("Testing raster-based packing algorithm")
+info("Testing raster-based mapping algorithm")
sim = Granular.createSimulation("raster-packing1")
sim.ocean = Granular.createRegularOceanGrid([1, 1, 1], [1., 1., 1.])
Granular.addGrainCylindrical!(sim, [0.5, 0.5], 0.4, 1.0)
t@@ -92,36 +92,45 @@ occupied = Granular.rasterMap(sim, 0.08)
occupied_ans = Array{Bool}([
0 0 0 0 0 0 0 0 0 0 0 0;
0 0 0 1 1 1 1 1 1 0 0 0;
-0 0 1 1 1 1 1 1 1 1 0 0;
-0 1 1 1 1 1 1 1 1 1 1 0;
+0 0 1 1 1 1 1 1 1 1 1 0;
0 1 1 1 1 1 1 1 1 1 1 0;
0 1 1 1 1 1 1 1 1 1 1 1;
0 1 1 1 1 1 1 1 1 1 1 1;
0 1 1 1 1 1 1 1 1 1 1 1;
+0 1 1 1 1 1 1 1 1 1 1 1;
0 1 1 1 1 1 1 1 1 1 1 0;
0 0 1 1 1 1 1 1 1 1 1 0;
-0 0 0 1 1 1 1 1 1 1 0 0;
-0 0 0 0 0 1 1 1 0 0 0 0])
+0 0 1 1 1 1 1 1 1 1 0 0;
+0 0 0 0 1 1 1 1 0 0 0 0])
@test occupied == occupied_ans
Granular.addGrainCylindrical!(sim, [0.03, 0.03], 0.02, 1.0)
occupied = Granular.rasterMap(sim, 0.08)
occupied_ans = Array{Bool}([
1 0 0 0 0 0 0 0 0 0 0 0;
0 0 0 1 1 1 1 1 1 0 0 0;
-0 0 1 1 1 1 1 1 1 1 0 0;
-0 1 1 1 1 1 1 1 1 1 1 0;
+0 0 1 1 1 1 1 1 1 1 1 0;
0 1 1 1 1 1 1 1 1 1 1 0;
0 1 1 1 1 1 1 1 1 1 1 1;
0 1 1 1 1 1 1 1 1 1 1 1;
0 1 1 1 1 1 1 1 1 1 1 1;
+0 1 1 1 1 1 1 1 1 1 1 1;
0 1 1 1 1 1 1 1 1 1 1 0;
0 0 1 1 1 1 1 1 1 1 1 0;
-0 0 0 1 1 1 1 1 1 1 0 0;
-0 0 0 0 0 1 1 1 0 0 0 0])
+0 0 1 1 1 1 1 1 1 1 0 0;
+0 0 0 0 1 1 1 1 0 0 0 0])
@test occupied == occupied_ans
+sim_init = deepcopy(sim)
+
+info("Testing raster-based mapping algorithm (power law GSD)")
+sim = deepcopy(sim_init)
+np_init = length(sim.grains)
+Granular.rasterPacking!(sim, 0.02, 0.04, verbose=verbose)
+@test np_init < length(sim.grains)
-#Granular.rasterPacking!(sim,
- #radius_max=.01,
- #radius_min=.01,
- #verbose=verbose)
+info("Testing raster-based mapping algorithm (uniform GSD)")
+sim = deepcopy(sim_init)
+np_init = length(sim.grains)
+Granular.rasterPacking!(sim, 0.02, 0.04, size_distribution="uniform",
+ verbose=verbose)
+@test np_init < length(sim.grains)