From e9965ab2a630ed4c8717b3e838769a39bd2d9195 Mon Sep 17 00:00:00 2001 From: Nino van Hooff Date: Thu, 26 Sep 2019 10:42:54 +0200 Subject: Revert the OneAtATimeIterator to the pre 06-2018 implementation. This seems like a better starting point to fix print head collisions, because we got less bug reports for it compared to the 2018 rewrite. CURA-6785 --- cura/OneAtATimeIterator.py | 227 +++++++++++++++++++-------------------------- 1 file changed, 95 insertions(+), 132 deletions(-) (limited to 'cura/OneAtATimeIterator.py') diff --git a/cura/OneAtATimeIterator.py b/cura/OneAtATimeIterator.py index a08f3ed2bf..ab97534ff4 100644 --- a/cura/OneAtATimeIterator.py +++ b/cura/OneAtATimeIterator.py @@ -1,149 +1,112 @@ -# Copyright (c) 2018 Ultimaker B.V. +# Copyright (c) 2015 Ultimaker B.V. # Cura is released under the terms of the LGPLv3 or higher. -import sys - -from shapely import affinity -from shapely.geometry import Polygon - -from UM.Scene.Iterator.Iterator import Iterator +from UM.Scene.Iterator import Iterator from UM.Scene.SceneNode import SceneNode +from functools import cmp_to_key +from UM.Application import Application - -# Iterator that determines the object print order when one-at a time mode is enabled. -# -# In one-at-a-time mode, only one extruder can be enabled to print. In order to maximize the number of objects we can -# print, we need to print from the corner that's closest to the extruder that's being used. Here is an illustration: -# -# +--------------------------------+ -# | | -# | | -# | | - Rectangle represents the complete print head including fans, etc. -# | X X | y - X's are the nozzles -# | (1) (2) | ^ -# | | | -# +--------------------------------+ +--> x -# -# In this case, the nozzles are symmetric, nozzle (1) is closer to the bottom left corner while (2) is closer to the -# bottom right. If we use nozzle (1) to print, then we better off printing from the bottom left corner so the print -# head will not collide into an object on its top-right side, which is a very large unused area. Following the same -# logic, if we are printing with nozzle (2), then it's better to print from the bottom-right side. -# -# This iterator determines the print order following the rules above. -# -class OneAtATimeIterator(Iterator): - +## Iterator that returns a list of nodes in the order that they need to be printed +# If there is no solution an empty list is returned. +# Take note that the list of nodes can have children (that may or may not contain mesh data) +class OneAtATimeIterator(Iterator.Iterator): def __init__(self, scene_node): - from cura.CuraApplication import CuraApplication - self._global_stack = CuraApplication.getInstance().getGlobalContainerStack() + super().__init__(scene_node) # Call super to make multiple inheritence work. + self._hit_map = [[]] self._original_node_list = [] - super().__init__(scene_node) # Call super to make multiple inheritance work. - - def getMachineNearestCornerToExtruder(self, global_stack): - head_and_fans_coordinates = global_stack.getHeadAndFansCoordinates() - - used_extruder = None - for extruder in global_stack.extruders.values(): - if extruder.isEnabled: - used_extruder = extruder - break - - extruder_offsets = [used_extruder.getProperty("machine_nozzle_offset_x", "value"), - used_extruder.getProperty("machine_nozzle_offset_y", "value")] - - # find the corner that's closest to the origin - min_distance2 = sys.maxsize - min_coord = None - for coord in head_and_fans_coordinates: - x = coord[0] - extruder_offsets[0] - y = coord[1] - extruder_offsets[1] - - distance2 = x**2 + y**2 - if distance2 <= min_distance2: - min_distance2 = distance2 - min_coord = coord - - return min_coord - - def _checkForCollisions(self) -> bool: - all_nodes = [] - for node in self._scene_node.getChildren(): - if not issubclass(type(node), SceneNode): - continue - convex_hull = node.callDecoration("getConvexHullHead") - if not convex_hull: - continue - - bounding_box = node.getBoundingBox() - if not bounding_box: - continue - from UM.Math.Polygon import Polygon - bounding_box_polygon = Polygon([[bounding_box.left, bounding_box.front], - [bounding_box.left, bounding_box.back], - [bounding_box.right, bounding_box.back], - [bounding_box.right, bounding_box.front]]) - - all_nodes.append({"node": node, - "bounding_box": bounding_box_polygon, - "convex_hull": convex_hull}) - - has_collisions = False - for i, node_dict in enumerate(all_nodes): - for j, other_node_dict in enumerate(all_nodes): - if i == j: - continue - if node_dict["bounding_box"].intersectsPolygon(other_node_dict["convex_hull"]): - has_collisions = True - break - - if has_collisions: - break - - return has_collisions - def _fillStack(self): - min_coord = self.getMachineNearestCornerToExtruder(self._global_stack) - transform_x = -int(round(min_coord[0] / abs(min_coord[0]))) - transform_y = -int(round(min_coord[1] / abs(min_coord[1]))) - - machine_size = [self._global_stack.getProperty("machine_width", "value"), - self._global_stack.getProperty("machine_depth", "value")] - - def flip_x(polygon): - tm2 = [-1, 0, 0, 1, 0, 0] - return affinity.affine_transform(affinity.translate(polygon, xoff = -machine_size[0]), tm2) - - def flip_y(polygon): - tm2 = [1, 0, 0, -1, 0, 0] - return affinity.affine_transform(affinity.translate(polygon, yoff = -machine_size[1]), tm2) - - if self._checkForCollisions(): - self._node_stack = [] - return - node_list = [] for node in self._scene_node.getChildren(): if not issubclass(type(node), SceneNode): continue - convex_hull = node.callDecoration("getConvexHull") - if convex_hull: - xmin = min(x for x, _ in convex_hull._points) - xmax = max(x for x, _ in convex_hull._points) - ymin = min(y for _, y in convex_hull._points) - ymax = max(y for _, y in convex_hull._points) + if node.callDecoration("getConvexHull"): + node_list.append(node) - convex_hull_polygon = Polygon.from_bounds(xmin, ymin, xmax, ymax) - if transform_x < 0: - convex_hull_polygon = flip_x(convex_hull_polygon) - if transform_y < 0: - convex_hull_polygon = flip_y(convex_hull_polygon) - node_list.append({"node": node, - "min_coord": [convex_hull_polygon.bounds[0], convex_hull_polygon.bounds[1]], - }) + if len(node_list) < 2: + self._node_stack = node_list[:] + return - node_list = sorted(node_list, key = lambda d: d["min_coord"]) + # Copy the list + self._original_node_list = node_list[:] + + ## Initialise the hit map (pre-compute all hits between all objects) + self._hit_map = [[self._checkHit(i,j) for i in node_list] for j in node_list] + + # Check if we have to files that block eachother. If this is the case, there is no solution! + for a in range(0,len(node_list)): + for b in range(0,len(node_list)): + if a != b and self._hit_map[a][b] and self._hit_map[b][a]: + return + + # Sort the original list so that items that block the most other objects are at the beginning. + # This does not decrease the worst case running time, but should improve it in most cases. + sorted(node_list, key = cmp_to_key(self._calculateScore)) + + todo_node_list = [_ObjectOrder([], node_list)] + while len(todo_node_list) > 0: + current = todo_node_list.pop() + for node in current.todo: + # Check if the object can be placed with what we have and still allows for a solution in the future + if not self._checkHitMultiple(node, current.order) and not self._checkBlockMultiple(node, current.todo): + # We found a possible result. Create new todo & order list. + new_todo_list = current.todo[:] + new_todo_list.remove(node) + new_order = current.order[:] + [node] + if len(new_todo_list) == 0: + # We have no more nodes to check, so quit looking. + todo_node_list = None + self._node_stack = new_order + + return + todo_node_list.append(_ObjectOrder(new_order, new_todo_list)) + self._node_stack = [] #No result found! + + + # Check if first object can be printed before the provided list (using the hit map) + def _checkHitMultiple(self, node, other_nodes): + node_index = self._original_node_list.index(node) + for other_node in other_nodes: + other_node_index = self._original_node_list.index(other_node) + if self._hit_map[node_index][other_node_index]: + return True + return False + + def _checkBlockMultiple(self, node, other_nodes): + node_index = self._original_node_list.index(node) + for other_node in other_nodes: + other_node_index = self._original_node_list.index(other_node) + if self._hit_map[other_node_index][node_index] and node_index != other_node_index: + return True + return False + + ## Calculate score simply sums the number of other objects it 'blocks' + def _calculateScore(self, a, b): + score_a = sum(self._hit_map[self._original_node_list.index(a)]) + score_b = sum(self._hit_map[self._original_node_list.index(b)]) + return score_a - score_b + + # Checks if A can be printed before B + def _checkHit(self, a, b): + if a == b: + return False + + overlap = a.callDecoration("getConvexHullBoundary").intersectsPolygon(b.callDecoration("getConvexHullHeadFull")) + if overlap: + return True + else: + return False + + +## Internal object used to keep track of a possible order in which to print objects. +class _ObjectOrder(): + def __init__(self, order, todo): + """ + :param order: List of indexes in which to print objects, ordered by printing order. + :param todo: List of indexes which are not yet inserted into the order list. + """ + self.order = order + self.todo = todo - self._node_stack = [d["node"] for d in node_list] -- cgit v1.2.3