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pyMKcam
Commit d9d40db7 authored by sumpfralle's avatar sumpfralle
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further improvements of the new polygon offsetting alorithm 

(it is still not finished)


git-svn-id: https://pycam.svn.sourceforge.net/svnroot/pycam/trunk@814 bbaffbd6-741e-11dd-a85d-61de82d9cad9
parent d31a2f68
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Showing with 119 additions and 71 deletions
src/pycam/Geometry/Polygon.py
View file @ d9d40db7
...@@ -324,81 +324,127 @@ class Polygon(TransformableContainer): ...@@ -324,81 +324,127 @@ class Polygon(TransformableContainer):
points = [] points = []
for index in range(len(self._points)): for index in range(len(self._points)):
points.append(get_shifted_vertex(index, offset)) points.append(get_shifted_vertex(index, offset))
new_lines = [] max_dist = 100 * epsilon
split_points = []
def test_point_near(p, others): def test_point_near(p, others):
for o in others: for o in others:
if p.sub(o).norm < 0.0001: if p.sub(o).norm < max_dist:
return True return True
return False return False
reverse_lines = []
shifted_lines = []
for index in range(len(points)): for index in range(len(points)):
next_index = (index + 1) % len(points) next_index = (index + 1) % len(points)
p1 = points[index] p1 = points[index]
p2 = points[next_index] p2 = points[next_index]
diff = p2.sub(p1) diff = p2.sub(p1)
if diff.norm < epsilon:
# fix the location of p2 (avoid gaps for diff.norm > 0)
points[next_index] = points[index]
# don't add the current line
else:
old_dir = self._points[next_index].sub( old_dir = self._points[next_index].sub(
self._points[index]).normalized() self._points[index]).normalized()
if diff.normalized() != old_dir: if diff.normalized() != old_dir:
# the direction turned around - this offset is too big # the direction turned around
print "TURNAROUND" if diff.norm > max_dist:
# the offset was too big
return None return None
else: else:
new_line = Line(p1, p2) reverse_lines.append(index)
if index == len(points) - 1: shifted_lines.append((True, Line(p1, p2)))
# Don't check for a collision of the last line with the else:
# first line. shifted_lines.append((False, Line(p1, p2)))
other_index = 1 # look for reversed lines
index = 0
while index < len(shifted_lines):
line_reverse, line = shifted_lines[index]
if line_reverse:
prev_index = (index - 1) % len(shifted_lines)
next_index = (index + 1) % len(shifted_lines)
prev_reverse, prev_line = shifted_lines[prev_index]
while prev_reverse and (prev_index != next_index):
prev_index = (prev_index - 1) % len(shifted_lines)
prev_reverse, prev_line = shifted_lines[prev_index]
if prev_index == next_index:
# no lines are left
print "out 1"
return []
next_reverse, next_line = shifted_lines[next_index]
while next_reverse and (prev_index != next_index):
next_index = (next_index + 1) % len(shifted_lines)
next_reverse, next_line = shifted_lines[next_index]
if prev_index == next_index:
# no lines are left
print "out 2"
return []
if prev_line.p2.sub(next_line.p1).norm > max_dist:
cp, dist = prev_line.get_intersection(next_line)
else:
cp = prev_line.p2
if cp:
shifted_lines[prev_index] = (False, Line(prev_line.p1, cp))
shifted_lines[next_index] = (False, Line(cp, next_line.p2))
else:
cp, dist = prev_line.get_intersection(next_line, infinite_lines=True)
raise BaseException("Expected intersection not found: " \
+ "%s - %s - %s(%d) / %s(%d)" % (cp, shifted_lines[prev_index+1:next_index], prev_line, prev_index, next_line, next_index))
if index > next_index:
# we wrapped around the end of the list
break
else:
index = next_index + 1
else: else:
index += 1
non_reversed = [line for reverse, line in shifted_lines
if not reverse and line.len > 0]
# split the list of lines into groups (based on intersections)
split_points = []
index = 0
while index < len(non_reversed):
other_index = 0 other_index = 0
# Check for any intersections with previous lines (except while other_index < len(non_reversed):
# for the direct predecessor). other_line = non_reversed[other_index]
already_added = False if (other_index == index) \
while other_index < len(new_lines) - 1: or (other_index == ((index - 1) % len(non_reversed))) \
other_line = new_lines[other_index] or (other_index == ((index + 1) % len(non_reversed))):
cp, dist = new_line.get_intersection(other_line) # skip neighbours
if not cp is None:
# There is a collision - let's check if the split
# happened at the end of one of these lines.
split_points.append(cp)
if test_point_near(cp, (p1, p2)):
# maybe we need to split 'other_line'
if not test_point_near(cp, (other_line.p1, other_line.p2)):
line_part1 = Line(other_line.p1, cp)
line_part2 = Line(cp, other_line.p2)
# remove the old line
new_lines.pop(other_index)
new_lines.insert(other_index, line_part1)
new_lines.insert(other_index + 1, line_part2)
# Skip the pointless check for the second
# part of the splitted 'other_line'.
other_index += 1 other_index += 1
elif test_point_near(cp, (other_line.p1, other_line.p2)): continue
if not test_point_near(cp, (p1, p2)): line = non_reversed[index]
if already_added: cp, dist = line.get_intersection(other_line)
raise BaseException("Already added before") if cp:
new_lines.append(Line(p1, cp)) if not test_point_near(cp,
new_lines.append(Line(cp, p2)) (line.p1, line.p2, other_line.p1, other_line.p2)):
already_added = True # the collision is not close to an end of the line
else:
# a split within the line -> problem
return None return None
elif (cp == line.p1) or (cp == line.p2):
# maybe we have been here before
if not cp in split_points:
split_points.append(cp)
elif (cp.sub(line.p1).norm < max_dist) \
or (cp.sub(line.p2).norm < max_dist):
if cp.sub(line.p1).norm < cp.sub(line.p2).norm:
non_reversed[index] = Line(cp, line.p2)
else:
non_reversed[index] = Line(line.p1, cp)
non_reversed.pop(other_index)
non_reversed.insert(other_index,
Line(other_line.p1, cp))
non_reversed.insert(other_index + 1,
Line(cp, other_line.p2))
split_points.append(cp)
if other_index < index:
index += 1
# skip the second part of this line
other_index += 1 other_index += 1
# the new line is ok else:
if not already_added: # the split of 'other_line' will be handled later
new_lines.append(new_line) pass
TODO: move the splitting of lines down here other_index += 1
# split the list of lines into groups (based on intersections) index += 1
print "Lines:", new_lines
print "Points:", split_points
groups = [[]] groups = [[]]
current_group = 0 current_group = 0
for line in new_lines: split_here = False
if test_point_near(line.p1, split_points): for line in non_reversed:
if line.p1 in split_points:
split_here = True
if split_here:
split_here = False
# check if any preceeding group fits to the point # check if any preceeding group fits to the point
for index, group in enumerate(groups): for index, group in enumerate(groups):
if not group: if not group:
...@@ -414,19 +460,23 @@ class Polygon(TransformableContainer): ...@@ -414,19 +460,23 @@ class Polygon(TransformableContainer):
groups.append([line]) groups.append([line])
else: else:
groups[current_group].append(line) groups[current_group].append(line)
if line.p2 in split_points:
split_here = True
result_polygons = [] result_polygons = []
for group in groups: for group in groups:
if len(group) <= 2: if len(group) <= 2:
continue continue
poly = Polygon(self.plane) poly = Polygon(self.plane)
#print "**************************************"
for line in group: for line in group:
#print line
poly.append(line) poly.append(line)
if self._is_closed: if self._is_closed and ((not poly._is_closed) \
if poly.is_outer() != poly.is_outer(): or (self.is_outer() != poly.is_outer())):
continue continue
else: elif (not self._is_closed) and (poly.get_area() != 0):
if poly.get_area() != 0:
continue continue
else:
result_polygons.append(poly) result_polygons.append(poly)
return result_polygons return result_polygons
...@@ -445,16 +495,14 @@ class Polygon(TransformableContainer): ...@@ -445,16 +495,14 @@ class Polygon(TransformableContainer):
result = self.get_offset_polygons_validated(middle) result = self.get_offset_polygons_validated(middle)
if result is None: if result is None:
upper = middle upper = middle
elif len(result) > 1: else:
print "POLYGON SPLIT at %s: %d" % (middle, len(result)) # the original polygon was splitted or modified
# the original polygon was splitted print "Next level: %s" % str(middle)
shifted_sub_polygons = [] shifted_sub_polygons = []
for sub_poly in result: for sub_poly in result:
shifted_sub_polygons.extend( shifted_sub_polygons.extend(
sub_poly.get_offset_polygons(offset - middle)) sub_poly.get_offset_polygons(offset - middle))
return shifted_sub_polygons return shifted_sub_polygons
else:
lower = middle
loop_limit -= 1 loop_limit -= 1
# no split event happened -> no valid shifted polygon # no split event happened -> no valid shifted polygon
return [] return []
......
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