nic/drawing-robot-ros2
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Implement basic SVG primitives and 'path' skeleton

Browse Source
This commit is contained in:
Nicolas Hiillos
2023-01-30 17:21:45 +02:00
parent bd49409c17
commit 06a595640a
2 changed files with 123 additions and 13 deletions
Download Patch File Download Diff File Expand all files Collapse all files

10
src/drawing_controller/drawing_controller/drawing_controller.py
View File

@@ -71,8 +71,12 @@ class DrawingController(Node):
xml = ET.parse(svgpath)
svg = xml.getroot()
#self.map_point = map_point_function(float(svg.get('width')), float(svg.get('height')), 0.1, 0.5, -0.2, 0.2)
self.map_point = map_point_function(float(svg.get('width')), float(svg.get('height')), 0.0, 1.0, 0.0, 1.0)
self.lines = []
try:
self.map_point = map_point_function(float(svg.get('width')), float(svg.get('height')), 0.0, 1.0, 0.0, 1.0)
except:
self.map_point = map_point_function(1000, 1000, 0.0, 1.0, 0.0, 1.0)
self.lines = [ ((0,0),(0,0)) ]
for child in svg:
if (child.tag == 'line'):
p1 = (float(child.get('x1')), float(child.get('y1')))
@@ -80,7 +84,7 @@ class DrawingController(Node):
self.lines.append((p1,p2))
self.svg_processor = SVGProcessor(self.get_logger())
self.svg_processor.process_svg(svgpath)
print(self.svg_processor.process_svg(svgpath))
def send_goal(self, motion):
self.busy = True

126
src/drawing_controller/drawing_controller/svg_processor.py
View File

@@ -1,31 +1,136 @@
#!/usr/bin/env python3
import rclpy
import lxml.etree as ET
class SVGProcessor():
"""
Class which reads an svg file and creates sequences of points
...
Attributes
----------
primitive_fns : dict
contains a mapping of SVG primitive names to functions that produce points
Methods
-------
Services
-------
Topics
-------
"""
def __init__(self, logger):
self.logger = logger
# A dict containing svg primitive names mapping to functions that handle them
self.primitives = {
self.primitive_fns = {
# Reference:
# https://developer.mozilla.org/en-US/docs/Web/SVG/Element
#"line": lambda p: print("LINE"),
"line": self.primitive_line,
"polyline": self.primitive_polyline,
"polygon": self.primitive_polygon,
}
def get_primitive(self, primitive):
log_error = lambda p: self.logger.error("'{}' not supported".format(p.tag))
return self.primitives.get(primitive.tag, log_error)
def get_primitive_fn(self, primitive):
'''
Looks up the primitive tag name in the dictionary of functions.
Parameters:
primitive (lxml child): the primitive from the svg file
Returns:
primitive_fn ():
'''
def log_error(p, _):
self.logger.error("'{}' not supported".format(p.tag))
return []
return self.primitive_fns.get(primitive.tag, log_error)
def down_and_up(self, points):
down = (points[0][0], points[0][1], 1)
up = (points[-1][0], points[-1][1], 1)
return [down] + points + [up]
def primitive_line(self, child, map_point):
p1 = map_point(float(child.get('x1')), float(child.get('y1')))
p2 = map_point(float(child.get('x2')), float(child.get('y2')))
return [
(p1[0],p1[1],0),
(p2[0],p2[1],0),
]
def primitive_polyline(self, child, map_point):
points = child.get('points').split(' ')
points = [(map_point(float(p[0])),
map_point(float(p[1])))
for p in points.split(',')]
output = []
for p in points:
output.append((p[0],p[1],0))
return output
def primitive_polygon(self, child, map_point):
output = self.primitive_polyline(child, map_point)
output.append((output[0][0],output[0][1],0))
return output
# https://developer.mozilla.org/en-US/docs/Web/SVG/Attribute/d
def path_parser(self, child, map_point):
path = child.get('d')
self.logger.info("Parsing path :'{}...' with {} characters".format(path[:40], len(path)))
self.logger.error("Path parser not implemented")
return []
# https://stackoverflow.com/questions/30232031/how-can-i-strip-namespaces-out-of-an-lxml-tree
def strip_ns_prefix(self, tree):
#xpath query for selecting all element nodes in namespace
query = "descendant-or-self::*[namespace-uri()!='']"
#for each element returned by the above xpath query...
for element in tree.xpath(query):
#replace element name with its local name
element.tag = ET.QName(element).localname
return tree
def process_svg(self, svg_path):
with open(svg_path) as svg:
xml = ET.parse(svg)
with open(svg_path) as svg_file:
xml = ET.parse(svg_file)
svg = xml.getroot()
svg = self.strip_ns_prefix(svg)
map_point = self.map_point_function(1000,
1000)
if 'width' in svg.attrib:
map_point = self.map_point_function(float(svg.get('width')),
float(svg.get('height')))
elif 'viewBox' in svg.attrib:
# TODO parse viewBox
pass
else:
self.logger.error("Unable to get SVG dimensions")
motions = []
for child in svg:
f = self.get_primitive(child)
f(child)
self.logger.info("Attempting to process SVG primitive:'{}'".format(child.tag))
primitive_fn = self.primitive_line
# path can consist of multiple primitives
if (child.tag == 'path'):
for m in self.path_parser(child, map_point):
motions.append(m)
else:
primitive_fn = self.get_primitive_fn(child)
motions.append(primitive_fn(child, map_point))
motions_refined = []
for m in motions:
if m == []:
continue
self.logger.info("Refining:'{}'".format(m))
motions_refined.append(self.down_and_up(m))
return motions_refined
def translate(self, val, lmin, lmax, rmin, rmax):
lspan = lmax - lmin
@@ -39,3 +144,4 @@ class SVGProcessor():
y = self.translate(ypix, 0, y_pixels, 0, 1)
return (x,y)
return map_point