Outer AA Dimensions#

Vertical Dimension

Horizontal Dimension

Left position

Right position

Upper position

Lower position

Negative 270°

Positive 90°

Positive 0°

Negative 180°

Vertical Dimension	Horizontal Dimension

Left position	Right position	Upper position	Lower position
Negative 270°	Positive 90°	Positive 0°	Negative 180°

Outer AA Dimension Attributes#

Show/Hide dims_aa properties

im
PIL image handle, link to the calling program
ptA
Start coordinates
ptB
Finishing coordinates
extA
Two integer tuple, giving the extension line size and gap next to start,
extB
Two integer tuple, giving the extension line size and gap next to end, optional if the same as extA
text
Dimension text
font
Font of the text
textorient
Change text orientation, "h", "horizontal", "v", "vertical"
fill
Line colour, RGB tuple
back
Background colour, RGB tuple
tail
Show tails or arrows, default True
arrowhead
Three integer tuple describing the shape and size of the arrow
arrow
position of the arrow on the line, which influences the direction it points.

Dimensions taken to the outside of an item will have extension lines and text, often there are several dimensions chained one to another plus one overall dimension positioned outside of the chained dimensions. If the chained dimensions have arrows the effect can be rather cluttered, and if they have short tails the effect can look better. Which method to use is a matter of taste or what is considered standard.

These dimensions are vertical or horizontal, for slanting dimensions see the next section. The text on vertical dimensions runs vertically, whilst horizontal dimensions have horizontal text. If the default text orientation needs changing use textorient to change its orientation (horizontal or vertical).

It is assumed that the dimensions lie to the right of the item or above it, when using dimensions to the left of an item or below the item use negative extension sizes. When both extension lines are the same the second extender extB can be left without a value. If the object is not linear over the dimension, use different sizes for the extensions, extA and extB. Extension line lengths are given as a tuple of two integers, the first shows the drawn line length and the next the space between the object and drawn line, if no gap is required use a single integer.

Confirm that we are dealing with vertical or horizontal dimensions. Several positioning properties depend on the orientation, so the extension lines are horizontal on vertical dimensions and vertical on the horizontal dimensions.

Note

The outer dimension is based on its own coordinates, ptA and ptB. Position the dimension away from the object using the extension line lengths .

The extension lines are drawn according to the lengths given. Then either add the two 45" stubs or add arrows to the dimension line , finally add the angled text.

At the end you should have something like the following.

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

from PIL import Image, ImageDraw, ImageFont
from math import atan2, degrees, sin, cos
from DimLinesAA import dims_aa, WideLineAA, LineAA
from DimLinesPIL import int_up, polar2cart, angled_text


def dims_aa(im, dr, ptA, ptB, extA, extB=None, text=None, font=None, textorient=None,
        fill=(0,0,0), tail=True, arrowhead=(8, 10, 3), arrow='both'):
    # vertical and horizontal dimension with extension lines tailed lines ,
    # option to use arrows.
    # ptA, ptB dim coords, extA, extB extension lines to measured item,
    # positive to right when vertical or above it when horizontal
    # read from bottom - unidirectional, read from bottom and right - aligned

    if isinstance(extA, int) or len(extA) == 1:
        exta = extA if isinstance(extA, int) else extA[0]
    elif len(extA) == 2:
        exta = extA[0]
        if extA[0] * extA[1] < 0:
            raise Exception('extA: both entries of extension tuple extA {} ' \
                'should either be positive or negative'.format(extA))
    else:
        raise Exception('extA: The extension tuple extA {} should be one or ' \
                'two entries'.format(extA))
    if extB is None:
        extB = extA
        extb = exta
    elif isinstance(extB, int) or len(extB) == 1:
        extb = extB if isinstance(extB, int) else extB[0]
    elif len(extB) == 2:
        extb = extB[0]
        if extB[0] * extB[1] < 0:
            raise Exception('extB: The extension tuple extB {} should be one or ' \
                'two entries, if None then it will equal extA {}'.format(extB, extA))
    if textorient is not None and textorient not in  ('vertical', 'horizontal', 'h', 'v'):
        raise Exception('dims: textorient {} should be None or' \
                '"horizontal", "h", "vertical" or "v"'.format(textorient))

    font = ImageFont.load_default() if font is None else font
    # (wide, height)= font.getsize(text)
    unused1, unused2, wide, height = font.getbbox(text)

    h = height // 2
    w = wide // 2

    dx = dy = 0
    if ptA[0] == ptB[0]:
        # vertical dimension
        ang = 270 if exta > 0 else 90
        if textorient is None or textorient in ('vertical', 'v'):
            dx = -h -5 if exta > 0 else h+5 # text positioning
            phi = 90                        # text angle
        elif textorient in ('horizontal', 'h'):
            dx = -w - 5 if exta > 0 else w + 5
            phi = 0                         # text angle

    elif ptA[1] == ptB[1]:
        # horizontal dimension
        ang = 0 if exta > 0 else 180
        if textorient is None or textorient in ('horizontal', 'h'):
            dy = -h -5 if exta > 0 else +h +5
            phi = 0                        # text angle
        elif textorient in ('vertical', 'v'):
            dy = -w -5 if exta > 0 else +w +5 # text positioning
            phi = 90

    else:
        raise Exception('dims: should be vertical or horizontal '\
                        '{} {} coordinates'.format(ptA, ptB))


    # dimension line or tails
    if tail:
        LineAA(dr,ptA, ptB, fill=fill, back=back)
        # create 45° end stubs
        p2 = ptA[0]+3, ptA[1]+3
        p3 = ptA[0]-3, ptA[1]-3
        p4 = ptB[0]+3, ptB[1]+3
        p5 = ptB[0]-3, ptB[1]-3
        LineAA(dr, p2,p3, fill=fill, back=back)
        LineAA(dr, p4,p5, fill=fill, back=back)
    else:
        dimension_aa(im, dr, ptC, ptB=ptD, fill=fill, arrowhead=arrowhead,
                arrow='both')

    # extensions, leave a gap if extA 2 entries
    ptA3 = polar2cart(ptA, ang-90, 3)
    ptAe = polar2cart(ptA, ang+90, abs(exta))
    LineAA(dr,ptA3, ptAe, fill=fill, back=back)
    ptB3 = polar2cart(ptB, ang-90, 3)
    ptBe = polar2cart(ptB, ang+90, abs(extb))
    LineAA(dr,ptB3, ptBe, fill=fill, back=back)

    at = (ptA[0]+ptB[0])//2+dx,(ptA[1]+ptB[1])//2+dy

    angled_text(im, at, text=text, angle=phi, font=font, fill=fill, aall=0)

if __name__ == "__main__":

    c = (60,60)
    ptA = (c[0],c[1]-20) # (40, 60)
    ptB = (c[0],c[1]+20) # (80, 60)
    text = 'Text' #str(ptA)+','+ str(ptB)

    extA = (5, 3)
    extB = (10,3)
    atot = sum(extA)
    btot = sum(extB)
    font = ImageFont.truetype('consola.ttf', 12)
    back = (255,255,221)
    image2 = Image.new('RGB', (120, 120), back)
    sdraw = ImageDraw.Draw(image2)
    if ptA[0] == ptB[0]:
        WideLineAA(sdraw, (ptA[0]+atot, ptA[1]), (ptB[0]+btot, ptB[1]),
                fill=(0,0,255), back=back, width=2)
    else:
        WideLineAA(sdraw, (ptA[0], ptA[1]+atot), (ptB[0], ptB[1]+btot),
                fill=(0,0,255), back=back, width=2)

    dims_aa(image2,sdraw, ptA, ptB, extA, extB=extB, text=text, font=font)

    image2.show()
    #image2.save('../../temp/dims_aa'+str(ptA)+'-'+str(ptB)+'.png')

Outer AA Dimensions#

Outer AA Dimension Attributes#

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