Different Orientations#

The examples so far worked for vertical lines, let's expand on this. Our line length appears to be sorted out, the next problem is the second linspace. The start and finish points need to be calculated based on the change due to the length of the dash, but as we have seen this must be reduced by one, to account for the way a line is drawn:

# make second part of the line array
x2 = x0 + int_up(dash2 * cos(theta))
y2 = y0 + int_up(dash2 * sin(theta))
x3 = x1 + int_up(dash2 * cos(theta))
y3 = y1 + int_up(dash2 * sin(theta))

Change the orientation to horizontal and check the dash and gap sizes. Oops not what we want, it's a continuous line, check on the final array(fin_arr), it hasn't been sorted:

# sort along the column, where the maximum change occurs
if abs(x1 -x0) > abs(y1 -y0):
    fin_arr = int_(both_arr[both_arr[:, 0].argsort()])
else:
    fin_arr = int_(both_arr[both_arr[:, 1].argsort()])

When sorting along the column, select the appropriate column, the x or y one, [:, 0] and [:, 1] respectively. Use the column that changes most.

import sys
sys.path.append('../dims')

from PIL import Image, ImageDraw, ImageFont
from math import dist, atan2, sin, cos
from numpy import array, linspace, concatenate, int_
from DimLinesPIL import angled_text, dims, int_up

def line_dashed(dr, start_pos, end_pos, dash=(5,5), width = 1, fill='black'):
    # create dashed lines in PIL

    # unpack tuples
    x0, y0 = start_pos
    x1, y1 = end_pos
    dash0, dash1 = dash
    dash2 = dash0 - 1
    theta = atan2(y1 - y0, x1 - x0)

    # sort out lengths
    dash_gap_length = sum(dash)
    line_length = dist(start_pos, end_pos)

    # adjust length to suit start and end positions if required
    if line_length % dash_gap_length != 0:
        factor = line_length//dash_gap_length # + 1
        line_length = factor * dash_gap_length
        x1 = int_up(x0 + line_length * cos(theta))
        y1 = int_up(y0 + line_length * sin(theta))

    # inclusive number of dashes and gaps
    dash_amount = int_up(line_length / dash_gap_length) + 1

    start_arr = linspace((x0, y0), (x1, y1), dash_amount)

    # make second part of the line array
    x2 = x0 + int_up(dash2 * cos(theta))
    y2 = y0 + int_up(dash2 * sin(theta))
    x3 = x1 + int_up(dash2 * cos(theta))
    y3 = y1 + int_up(dash2 * sin(theta))

    end_arr = linspace((x2, y2), (x3, y3), dash_amount)

    both_arr = concatenate([start_arr, end_arr], axis=0)

    # sort along the column, where the maximum change occurs
    if abs(x1 -x0) > abs(y1 -y0):
        fin_arr = int_(both_arr[both_arr[:, 0].argsort()])
    else:
        fin_arr = int_(both_arr[both_arr[:, 1].argsort()])

    nr_lines = len(fin_arr)

    [dr.line([tuple(fin_arr[n]), tuple(fin_arr[n+1])], width=width, fill=fill)
            for n in range(0, nr_lines, 2)]

if __name__ == "__main__":
    Font = ImageFont.truetype('consola.ttf', 12)

    arr = array([[30, 10],
    [30, 24],
    [30, 40],
    [30, 54],
    [30, 70],
    [30, 84]])

    arr[:, 0], arr[:, 1] = arr[:, 1], arr[:, 0].copy() # swapping columns
    
    Nr_lines = len(arr)

    Dash =(15, 15)

    Start_pos = (10,30) # (30, 10)
    End_pos = (90, 30) # (30, 90)

    w, h = 100, 100
    image = Image.new('RGB', (w,h), '#FFFFDD')
    draw = ImageDraw.Draw(image)

    # wide, height = Font.getsize('(30, 84)')
    ununused1, unused2, wide, height = Font.getbbox('(30, 84)')

    for i in range(Nr_lines):
        angled_text(image, (arr[i][0], arr[i][1] + 10 + wide//2),text=str(arr[i]),
                angle=90, fill='black', font=Font)

    for j in range(Nr_lines - 1):
        # TypeError: only length-1 arrays can be converted to Python scalars
        dims(image, draw, arr[j], arr[j+1], (8, 2), text='15', font=Font, fill='lightgreen',
                textorient='vertical')

    line_dashed(draw, Start_pos, End_pos, dash=Dash, width = 1, fill='black')

    image.show()

Different Orientations#

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