tFix a few problems in checkForContacts - Granular.jl - Julia package for granular dynamics simulation
(HTM) git clone git://src.adamsgaard.dk/Granular.jl
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---
(DIR) commit 62b30ca4668b7809b1664cb98c0fb70c9c15e410
(DIR) parent 0ca0e4abf901666fd3795f8b126be72e52645352
(HTM) Author: Anders Damsgaard <andersd@riseup.net>
Date: Thu, 21 Dec 2017 15:06:37 -0500
Fix a few problems in checkForContacts
Diffstat:
M src/contact_search.jl | 12 +++++++-----
M src/packing.jl | 87 ++++++++++++++-----------------
M test/packing.jl | 13 +++++++------
3 files changed, 54 insertions(+), 58 deletions(-)
---
(DIR) diff --git a/src/contact_search.jl b/src/contact_search.jl
t@@ -155,20 +155,22 @@ position `position` and `radius`, against all grains registered in the `grid`.
Returns `true` if no contacts were found, and `false` if contacts were found.
# Arguments
+* `simulation::Simulation`: Simulation object containing grain positions.
* `grid::Any`: `Ocean` or `Atmosphere` grid containing sorted particles.
* `position::Vector{Float64}`: Candidate center position to probe for contacts
with existing grains [m].
* `radius::Float64`: Candidate radius [m].
"""
-function checkForContacts(grid::Any, x_candidate::Vector{Float64},
+function checkForContacts(simulation::Simulation,
+ grid::Any,
+ x_candidate::Vector{Float64},
r_candidate::Float64)
- sw = zeros(2); se = zeros(2); ne = zeros(2); nw = zeros(2)
distance_modifier = zeros(2)
no_overlaps_found = true
# Inter-grain position vector and grain overlap
- ix, iy = findCellContainingPoint(grid, x_candidate, sw, se, ne, nw)
+ ix, iy = findCellContainingPoint(grid, x_candidate)
# Check for overlap with existing grains
for ix_=(ix - 1):(ix + 1)
t@@ -180,8 +182,8 @@ function checkForContacts(grid::Any, x_candidate::Vector{Float64},
# skip iteration if target still falls outside grid after
# periodicity correction
- if ix_corrected < 1 || ix_corrected > nx ||
- iy_corrected < 1 || iy_corrected > ny
+ if ix_corrected < 1 || ix_corrected > size(grid.xh)[1] ||
+ iy_corrected < 1 || iy_corrected > size(grid.xh)[2]
continue
end
(DIR) diff --git a/src/packing.jl b/src/packing.jl
t@@ -82,6 +82,14 @@ function generateNeighboringPoint(x_i::Vector, r_i::Real,
return [x_i[1] + R * sin(T), x_i[2] + R * cos(T)], r_j
end
+function generateRandomDirection()
+ return rand() * 2. * pi
+end
+
+function getPositionDistancedFromPoint(T::Real, x_i::Vector, dist::Real)
+ return [x_i[1] + dist * sin(T), x_i[2] + dist * cos(T)]
+end
+
export irregularPacking!
"""
irregularPacking!(simulation[, radius_max, radius_min, sample_limit,
t@@ -108,6 +116,8 @@ function irregularPacking!(simulation::Simulation;
radius_max::Real=.1,
radius_min::Real=.1,
sample_limit::Integer=30,
+ padding_factor::Real=2.,
+ progressive_downwards_radius_search::Bool=false,
thickness::Real=1.,
seed::Integer=1,
plot_during_packing::Bool=false,
t@@ -154,10 +164,7 @@ function irregularPacking!(simulation::Simulation;
# point is found, instead remove `i` from the active list.
i = 0; j = 0;
x_active = zeros(2); x_candidate = zeros(2);
- r_active = 0.; r_candidate = 0.
- distance_modifier = zeros(2)
- sw = zeros(2); se = zeros(2); ne = zeros(2); nw = zeros(2)
- nx, ny = size(grid.xh)
+ r_active = 0.; r_candidate = 0.; T = 0.
n = 0
neighbor_found = false
t@@ -167,25 +174,33 @@ function irregularPacking!(simulation::Simulation;
x_active = simulation.grains[i].lin_pos
r_active = simulation.grains[i].contact_radius
- #r_candidate = rand()*(radius_max - radius_min) + radius_min
neighbor_found = false
for j=1:sample_limit
- # add points at wider distance for the first 10 iterations, and
- # afterwards directly neighboring points
- if j <= 2
- x_candidate, r_candidate = generateNeighboringPoint(x_active,
- r_active,
- radius_max,
- radius_min,
- padding=2.0*radius_max)
+ if progressive_downwards_radius_search
+ # Generate a point positioned at r_active + radius_max from the
+ # position x_active.
+ T = generateRandomDirection()
+ r_candidate = radius_max
+ x_candidate = getPositionFromPoint(x_active, T,
+ r_active + r_candidate)
else
- x_candidate, r_candidate = generateNeighboringPoint(x_active,
- r_active,
- radius_max,
- radius_min)
+ if j <= 2
+ x_candidate, r_candidate = generateNeighboringPoint(
+ x_active,
+ r_active,
+ radius_max,
+ radius_min,
+ padding=padding_factor*radius_max)
+ else
+ x_candidate, r_candidate = generateNeighboringPoint(
+ x_active,
+ r_active,
+ radius_max,
+ radius_min)
+ end
end
t@@ -193,37 +208,15 @@ function irregularPacking!(simulation::Simulation;
continue # skip this candidate
end
- # Inter-grain position vector and grain overlap
- ix, iy = findCellContainingPoint(grid, x_candidate, sw, se, ne, nw)
- no_overlaps_found = true
-
- # Check for overlap with existing grains
- for ix_=(ix - 1):(ix + 1)
- for iy_=(iy - 1):(iy + 1)
-
- # correct indexes if necessary
- ix_corrected, iy_corrected = periodicBoundaryCorrection!(
- grid, ix_, iy_,
- distance_modifier)
-
- # skip iteration if target still falls outside grid after
- # periodicity correction
- if ix_corrected < 1 || ix_corrected > nx ||
- iy_corrected < 1 || iy_corrected > ny
- continue
- end
-
- for idx in grid.grain_list[ix_corrected, iy_corrected]
- if norm(simulation.grains[idx].lin_pos - x_candidate +
- distance_modifier) -
- (simulation.grains[idx].contact_radius +
- r_candidate) < 0.
-
- no_overlaps_found = false
- break # overlap: skip this candidate
- end
- end
+
+ if progressive_downwards_radius_search
+ while no_overlaps_found == false
+ error("not yet implemented")
end
+ else
+ no_overlaps_found = checkForContacts(simulation, grid,
+ x_candidate,
+ r_candidate)
end
# if the grain candidate doesn't overlap with any other grains, add
(DIR) diff --git a/test/packing.jl b/test/packing.jl
t@@ -40,25 +40,26 @@ end
info("Testing irregular (Poisson-disk) packing generation (monodisperse size)")
-sim = Granular.createSimulation("poisson1")
+sim = Granular.createSimulation("poisson1-monodisperse-nopadding")
sim.ocean = Granular.createRegularOceanGrid([1, 1, 1], [1., 1., 1.])
Granular.irregularPacking!(sim,
radius_max=.1,
radius_min=.1,
+ padding_factor=0.,
verbose=true)
info("Testing irregular (Poisson-disk) packing generation (wide PSD)")
-sim = Granular.createSimulation("poisson2")
+sim = Granular.createSimulation("poisson2-wide-nopadding")
sim.ocean = Granular.createRegularOceanGrid([1, 1, 1], [1., 1., 1.])
Granular.irregularPacking!(sim,
radius_max=.1,
radius_min=.001,
+ padding_factor=0.,
verbose=true)
-
-info("Testing irregular (Poisson-disk) packing generation (intermediate PSD)")
-sim = Granular.createSimulation("poisson3")
+sim = Granular.createSimulation("poisson3-wide-padding")
sim.ocean = Granular.createRegularOceanGrid([1, 1, 1], [1., 1., 1.])
Granular.irregularPacking!(sim,
radius_max=.1,
- radius_min=.01,
+ radius_min=.001,
+ padding_factor=2.,
verbose=true)