#!/usr/bin/env python3 ''' Globe rendering extension for Inkscape Copyright (C) 2009 Gerrit Karius This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. About the Globe rendering extension: ''' from __future__ import division import inkex from math import * from lxml import etree #TODO: put the globe in the center of the view canvas def draw_ellipse_rotated(cx,cy,rx,ry, width, fill, name, parent, rotationAngle): a = cos(rotationAngle) b = sin(rotationAngle) c = -sin(rotationAngle) d = cos(rotationAngle) e = -(a*cx + c*cy) + cx f = -(b*cx + d*cy) + cy style = { 'stroke': '#000000', 'stroke-width':str(width), 'fill':fill} if rx == 0: x1 = cx x2 = cx y1 = cy - ry y2 = cy + ry circle_attribs = {'style':str(inkex.Style(style)), inkex.addNS('label','inkscape'):name, 'd':'M '+str(x1)+','+str(y1)+' L '+str(x2)+','+str(y2), 'transform':'matrix('+str(a)+','+str(b)+','+str(c)+','+str(d)+','+str(e)+','+str(f)+')'} elif ry == 0: x1 = cx - rx x2 = cx + rx y1 = cy y2 = cy circle_attribs = {'style':str(inkex.Style(style)), inkex.addNS('label','inkscape'):name, 'd':'M '+str(x1)+','+str(y1)+' L '+str(x2)+','+str(y2), 'transform':'matrix('+str(a)+','+str(b)+','+str(c)+','+str(d)+','+str(e)+','+str(f)+')'} else: circle_attribs = {'style':str(inkex.Style(style)), inkex.addNS('label','inkscape'):name, inkex.addNS('cx','sodipodi'):str(cx), inkex.addNS('cy','sodipodi'):str(cy), inkex.addNS('rx','sodipodi'):str(rx), inkex.addNS('ry','sodipodi'):str(ry), inkex.addNS('type','sodipodi'):'arc', 'transform':'matrix('+str(a)+','+str(b)+','+str(c)+','+str(d)+','+str(e)+','+str(f)+')'} etree.SubElement(parent, inkex.addNS('path','svg'), circle_attribs) def draw_ellipse_segment_rotated(cx,cy,rx,ry, width, fill, name, parent, rotationAngle, segmentAngleStart, segmentAngleEnd): a = cos(rotationAngle) b = sin(rotationAngle) c = -sin(rotationAngle) d = cos(rotationAngle) e = -(a*cx + c*cy) + cx f = -(b*cx + d*cy) + cy style = { 'stroke': '#000000', 'stroke-width':str(width), 'fill':fill} if rx == 0: x1 = cx x2 = cx y1 = cy - ry y2 = cy + ry circle_attribs = {'style':str(inkex.Style(style)), inkex.addNS('label','inkscape'):name, 'd':'M '+str(x1)+','+str(y1)+' L '+str(x2)+','+str(y2), 'transform':'matrix('+str(a)+','+str(b)+','+str(c)+','+str(d)+','+str(e)+','+str(f)+')'} elif ry == 0: x1 = cx - rx x2 = cx + rx y1 = cy y2 = cy circle_attribs = {'style':str(inkex.Style(style)), inkex.addNS('label','inkscape'):name, 'd':'M '+str(x1)+','+str(y1)+' L '+str(x2)+','+str(y2), 'transform':'matrix('+str(a)+','+str(b)+','+str(c)+','+str(d)+','+str(e)+','+str(f)+')'} else: circle_attribs = {'style':str(inkex.Style(style)), inkex.addNS('label','inkscape'):name, inkex.addNS('cx','sodipodi'):str(cx), inkex.addNS('cy','sodipodi'):str(cy), inkex.addNS('rx','sodipodi'):str(rx), inkex.addNS('ry','sodipodi'):str(ry), inkex.addNS('start','sodipodi'):str(segmentAngleStart), inkex.addNS('end','sodipodi'):str(segmentAngleEnd), inkex.addNS('open','sodipodi'):'true', inkex.addNS('type','sodipodi'):'arc', 'transform':'matrix('+str(a)+','+str(b)+','+str(c)+','+str(d)+','+str(e)+','+str(f)+')'} etree.SubElement(parent, inkex.addNS('path','svg'), circle_attribs) class Globe(inkex.Effect): def __init__(self): inkex.Effect.__init__(self) self.arg_parser.add_argument("--longitudeLineCount", type=int, default=15, help="Number of longitude lines") self.arg_parser.add_argument("--latitudeLineCount", type=int, default=15, help="Number of latitude lines") self.arg_parser.add_argument("--rotationXDegrees", type=float, default=45, help="Rotation around X axis (degrees)") self.arg_parser.add_argument("--rotationYDegrees", type=float, default=-45, help="Rotation around Y axis (degrees)") self.arg_parser.add_argument("--isSeeThrough", type=inkex.Boolean, default=False, help="Is the globe see-through") def effect(self): name = 'globe' # globe fill and stroke style fill = 'none' width = 1 #input parameters - globe center and radius cyb = 500.0 cxb = 500.0 rb = 100.0 longitudeRotationAngleDegrees = float(self.options.rotationYDegrees) tiltForwardAngleDegrees = float(self.options.rotationXDegrees) # inputs range fixing # tiltForwardAngle is adjusted to vary from 0 <= angle < pi if tiltForwardAngleDegrees >= 180.0: tiltForwardAngleDegrees -= 180.0 elif tiltForwardAngleDegrees < 180.0: tiltForwardAngleDegrees += 180.0 if self.options.longitudeLineCount > 0: angleSpacingLongitudeLinesDegrees = 180.0 / float(self.options.longitudeLineCount); # longitudeAngle is wrapped to vary from 0 <= angle < angleSpacingLongitudeLines. while longitudeRotationAngleDegrees < 0: longitudeRotationAngleDegrees += angleSpacingLongitudeLinesDegrees while longitudeRotationAngleDegrees >= angleSpacingLongitudeLinesDegrees: longitudeRotationAngleDegrees -= angleSpacingLongitudeLinesDegrees # units conversion from degrees to radians tiltForwardAngle = tiltForwardAngleDegrees * pi / 180.0; initialAngleLongitudeLines = longitudeRotationAngleDegrees * pi / 180.0 # derived parameters rxb = rb ryb = rb # # start drawing # # create the group to put the globe in group_attribs = {inkex.addNS('label','inkscape'):name} parent = etree.SubElement(self.svg.get_current_layer(), 'g', group_attribs) # draw the outside border draw_ellipse_rotated(cxb,cyb,rxb,ryb, width, fill, 'border', parent, 0) # draw the longitude lines # elipse #0 corresponds to ring on the front (visible only as a straight vertical line) # elipse #n-1 corresponds to the ring that is almost 180 degrees away # elipse #n/2 corresponds to ring around the side (overlaps with globe boundary) (only if n is even) if self.options.longitudeLineCount > 0: angleSpacingLongitudeLines = pi / float(self.options.longitudeLineCount); yOfPole = ryb * cos(tiltForwardAngle) for i in range(0, self.options.longitudeLineCount): lineName = 'longitude' + str(i) # longitudeAngle is always from 0 to pi. # rotation angle is always from 0 to pi. # rx is never negative. longitudeAngle = ((float(i)) * angleSpacingLongitudeLines) + initialAngleLongitudeLines if tiltForwardAngleDegrees == 0 or tiltForwardAngleDegrees == 180.0: if longitudeAngle < pi/2: rotationAngle = 0.0 else: rotationAngle = pi rx = rxb * sin(longitudeAngle) arcStart = pi/2 arcEnd = -pi/2 else: rotationAngle = acos(cos(longitudeAngle) / sqrt(1 - pow(sin(longitudeAngle)*cos(tiltForwardAngle), 2))) rx = rxb * sin(longitudeAngle) * cos(tiltForwardAngle) if rx < 0: rx = -rx arcStart = -pi/2 arcEnd = pi/2 else: arcStart = pi/2 arcEnd = -pi/2 ry = ryb cx = cxb cy = cyb if self.options.isSeeThrough: draw_ellipse_rotated(cx,cy,rx,ry, width, fill, lineName, parent, rotationAngle) else: draw_ellipse_segment_rotated(cx,cy,rx,ry, width, fill, lineName, parent, rotationAngle, arcStart, arcEnd) # draw the latitude lines # elipse #0 corresponds to ring closest to north pole. # elipse #n-1 corresponds to ring closest to south pole. # equator is ring #(n-1)/2 (only if n is odd). if self.options.latitudeLineCount > 0: angleSpacingLatitudeLines = pi / (1.0 + float(self.options.latitudeLineCount)); yOfPole = ryb * cos(tiltForwardAngle) for i in range(0, self.options.latitudeLineCount): lineName = 'latitude' + str(i) # angleOfCurrentLatitudeLine is always from 0 to pi. # tiltForwardAngle is always from 0 to pi. # ry is never negative. angleOfCurrentLatitudeLine = float(i + 1) * angleSpacingLatitudeLines rx = rxb * sin(angleOfCurrentLatitudeLine) ry = rx * sin(tiltForwardAngle) cx = cxb cy = cyb - yOfPole*cos(angleOfCurrentLatitudeLine) if self.options.isSeeThrough: #inkex.utils.debug(cx) #inkex.utils.debug(cy) #inkex.utils.debug(rx) #inkex.utils.debug(ry) #inkex.utils.debug(width) #inkex.utils.debug(fill) #inkex.utils.debug(lineName) #inkex.utils.debug(parent) draw_ellipse_rotated(cx,cy,rx,ry, width, fill, lineName, parent, 0) else: if tiltForwardAngle > pi/2: # tilt away from viewaer if rxb * cos(angleOfCurrentLatitudeLine) / cos(tiltForwardAngle) > rxb: # elipse is not visible pass else: if rxb * cos(angleOfCurrentLatitudeLine) / cos(tiltForwardAngle) < -rxb: # elipse is all visible segmentAngle = pi else: # elipse is only partially visible segmentAngle = acos(max(-1,min(1, -tan(tiltForwardAngle) / tan(angleOfCurrentLatitudeLine)))) draw_ellipse_segment_rotated(cx,cy,rx,ry, width, fill, lineName, parent, 0, pi/2+segmentAngle, pi/2-segmentAngle) else: # tilt towards viewer if rxb * cos(angleOfCurrentLatitudeLine) / cos(tiltForwardAngle) < -rxb: # elipse is not visible pass else: if rxb * cos(angleOfCurrentLatitudeLine) / cos(tiltForwardAngle) > rxb: # elipse is all visible segmentAngle = pi else: # elipse is only partially visible segmentAngle = acos(max(-1,min(1, tan(tiltForwardAngle) / tan(angleOfCurrentLatitudeLine)))) draw_ellipse_segment_rotated(cx,cy,rx,ry, width, fill, lineName, parent, 0, -pi/2+segmentAngle, -pi/2-segmentAngle) if __name__ == '__main__': Globe().run()