MuesliMix/prototype/svg_utils.py

import numpy as np
import math

# scale in inkscape
# 1 unit = 0.28222 mm
svg_scale = 1000.0 / 282.222


def svg_circle(id, name, c, r):
    # create circle object centered at point c with radius r
    text = ['      <circle\n',
            '       id="circle{}"\n'.format(id),
            '       inkscape:label="{}"\n'.format(name),
            '       style="fill:none;stroke:#000000;stroke-width:0.1mm"\n',
            '       r="{}mm"\n'.format(r),
            '       cy="{}mm"\n'.format(c[1]),
            '       cx="{}mm" />\n'.format(c[0])]

    return text


def svg_puzzle(p, size, angle):
    # convert angle to radians
    angle = angle / 360.0 * 2.0 * np.pi

    # compute points
    """
        v1 and v2 are orthogonal vectors

        construction of points (starting at p):

           p3 <------   -2 v1  ------ p2
                                      ^
                                      |
                                      v2
                                      |
                                      |
           p4 <-- -v1 --  p -- v1 --> p1

        then between points p2 and p3 with draw an arc
    """
    v1 = np.array([np.cos(angle), np.sin(angle)])
    v2 = np.array([v1[1], -v1[0]])
    p1 = p + size * v1
    p2 = p1 + size * v2
    p3 = p2 - 2.0 * size * v1
    p4 = p - size * v1

    # convert to svg units
    p1 *= svg_scale
    p2 *= svg_scale
    p3 *= svg_scale
    p4 *= svg_scale

    radius_scaled = 1.25 * size * svg_scale

    text = ['      <path \n     '
            '        id="path666" \n       '
            '        style="fill:none;stroke:#ff0000;stroke-width:1.60000002" \n'
            '        d="M {} {} L {} {} A {} {} 0 1 0 {} {} L {} {}"'
            '      />\n'.format(p1[0], p1[1], p2[0], p2[1], radius_scaled, radius_scaled, p3[0], p3[1], p4[0], p4[1])]

    return text


def svg_line_puzzle(start, end, puzzle_scale=1.0, linewidth=0.50, placement=0.5):
    # draws a line from start to end with a simple jigsaw puzzle style cutout in the middle
    # the size of the cutout can be controlled with the puzzle_scale parameter
    # compute points
    """
        v1 and v2 are orthogonal vectors

        construction of points (starting at p (middle between start and end)):

                 p2 -------   2 v1  -----> p3
                  ^
                  |
                 v2
                  |
                  |
     start ---   p1 <-- -v1 --  p -- v1 --> p4   --- end

        then between points p2 and p3 with draw an arc
    """
    v = end - start
    dist = np.linalg.norm(v)
    size = dist / 10.0 * puzzle_scale  # size of the cutout
    v = v / dist
    angle = math.atan2(v[1], v[0])  # angle of v

    # midpoint between start and end
    p = (1.0 - placement) * start + placement * end
    #p = np.mean([start, end], axis=0)

    v1 = np.array([np.cos(angle), np.sin(angle)])
    v2 = np.array([v1[1], -v1[0]])
    p1 = p - size * v1
    p2 = p1 + size * v2
    p3 = p2 + 2.0 * size * v1
    p4 = p + size * v1

    # convert to svg units
    p1 *= svg_scale
    p2 *= svg_scale
    p3 *= svg_scale
    p4 *= svg_scale
    start *= svg_scale
    end *= svg_scale

    radius_scaled = 1.25 * size * svg_scale

    text = ['      <path \n     '
            '        id="path666" \n       '
            '        style="fill:none;stroke:#000000;stroke-width:{}mm" \n'
            '        d="M {} {} L {} {} L {} {} A {} {} 0 1 1 {} {} L {} {} L {} {}"'
            '      />\n'.format(linewidth, start[0], start[1], p1[0], p1[1], p2[0], p2[1], radius_scaled, radius_scaled,
                                p3[0], p3[1], p4[0], p4[1], end[0], end[1])]

    return text


def svg_half_circle(id, name, c, r, angle, orientation_flag=1):
    # draws half a circle centered at c with radius r
    # angle specifies how the half circle should be rotated
    # the orientation flag determines if the upper or the lower half of the circle is drawn

    # convert angle to radians
    angle = angle / 360.0 * 2.0 * np.pi

    # compute starting point
    v = np.array([np.cos(angle), np.sin(angle)])
    begin = c + r * v  # in millimeters
    begin *= svg_scale  # in svg units

    # compute end point
    end = c - r * v  # in millimeters
    end *= svg_scale  # in svg units

    radius_scaled = r * svg_scale  # radius in svg units

    text = ['      <path \n     '
            '        id="path666" \n       '
            '        style="fill:none;stroke:#000000;stroke-width:0.60000002" \n'
            '        d="M {} {} A {} {} 0 {} {} {} {}"'
            '      />\n'.format(begin[0], begin[1], radius_scaled, radius_scaled, orientation_flag, orientation_flag,
                                end[0], end[1])]

    return text


def svg_arc(p1, p2, r, large_arc, sweep):
    begin = p1 * svg_scale
    end = p2 * svg_scale
    radius_scaled = r * svg_scale
    text = ['      <path \n     '
            '        id="path666" \n       '
            '        style="fill:none;stroke:#000000;stroke-width:0.60000002" \n'
            '        d="M {} {} A {} {} 0 {} {} {} {}"'
            '      />\n'.format(begin[0], begin[1], radius_scaled, radius_scaled, large_arc, sweep,
                                end[0], end[1])]

    return text


def svg_rectangle(id, name, c):
    center = c['center']
    width = c['length']
    height = c['width']
    angle = c['angle_deg']
    x = np.sqrt(center[0] ** 2 + center[1] ** 2) - width / 2
    y = - height
    text = ['<g transform="rotate({})">\n '
            '<rect x="{}mm" y="{}mm" width="{}mm" height="{}mm" style="fill:none;stroke-width:0.1mm;stroke:rgb(0,0,0)" />\n '
            '</g>\n'
                .format(angle, x, y, width, height)]

    return text


def svg_line(p1, p2, width=1.0):
    text = ['<line x1="{}mm" y1="{}mm" x2="{}mm" y2="{}mm" style="stroke:rgb(0,0,0);stroke-width:{}mm" />'.format(p1[0],
                                                                                                                  p1[1],
                                                                                                                  p2[0],
                                                                                                                  p2[1],
                                                                                                                  width)]

    return text


def svg_gear_marking(tangent_coord, circle_midpoint, marking_length=5.0):
    c = tangent_coord
    v = np.array(c[0]) - np.array(circle_midpoint)
    v = v / np.linalg.norm(v)

    p1 = c[0]
    p2 = c[0] + v * marking_length

    text = svg_line(p1, p2)

    return text

def svg_segment_border_inner(angle, center_hole_radius, circle_pos, circle_radius, puzzle_scale=1.0, placement=0.5):
    a = angle
    a = a / 360.0 * 2.0 * np.pi
    r1 = np.linalg.norm(np.array(circle_pos)) - circle_radius
    vunit = np.array([np.cos(a), np.sin(a)])
    p1 = vunit * center_hole_radius
    p2 = vunit * r1
    text = svg_line_puzzle(p1, p2, puzzle_scale=puzzle_scale, placement=placement)

    return text

def svg_segment_border_outer(angle, plate_pitch_radius, plate_gear_module, circle_pos, circle_radius, puzzle_scale=1.0,
                             placement=0.5):
    a = angle
    a = a / 360.0 * 2.0 * np.pi
    vunit = np.array([np.cos(a), np.sin(a)])
    r2 = np.linalg.norm(np.array(circle_pos)) + circle_radius
    p3 = vunit * r2
    r3 = plate_pitch_radius - plate_gear_module
    p4 = vunit * r3
    text = svg_line_puzzle(p3, p4, puzzle_scale=puzzle_scale, placement=placement)

    return text