File talk:Black and white right turn.svg

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This SVG file has an interesting history.

Its source is J4A.svg, a very simple drawing consisting only of three or four bent blue strokes, enclosed by a rectangle with rounded edges.

Without any problem, the strokes can be drawn with one single path.

Created with Adobe Illustrator, its structure consists of three pathes and four polygones; as a miracle, there are also ten tiny circles (EURions??), but at positions where they are invisible.

The image derivated from it using Sodipodi-Inkscape has the same size 576×192, just the blue strokes are black and the transparent inbetween in white. It has as well three pathes and four polygones; even the ten circles are there, in blue color of J4A.svg, but they are still invisible. Sodipodi preferes a more complicated style to define the structures, increasing the file size to more than double of Adobe size: from 3690 to 7724 bytes.

The image (Sodipodi, version 20:37,13 August 2010/7724 bytes/Setreset) has several severe errors.
Everywhere when the white strokes meet the surrounding, threetimes the upper and threetimes the lower edge, and even at the right edge, its black stroke is outside the surrounding. This is clearly visible, especially when zoomed a bit. The same is with Black and white left turn.svg.

To draw that image with a reasonable effort, it seems the best and cheapest way to get the rounded edges with the clipping function. If it is not possible to define the clip shape and to draw the sourrounding by the same element, it is necassary to define that element twice. The path is then rather simple, it can be like

<path fill="none" stroke-width="68" d="
M-83-34 47,96-83 226
m192,0 130-130-130-130
m192,0 130,130-130,130
m192,0 130-130-130-130
" clip-path="url(#o)"/>

to draw the four black stripes, leaving the other space white.

For the file Black and white left turn.svg it looks almost the same,

<path fill="none" stroke-width="68" d="
M83-34-47,96 83,226
m192,0-130-130 130-130
m192,0-130,130 130,130
m192,0-130-130 130-130
" clip-path="url(#o)"/>

because now the arrows point to the left. There seems no need for an abundary exactness, integers ccordinates are sufficient to get an impression like from Sodipodi.

All these was done with 409 bytes (Manual version 21:25,15 January 2011/409 bytes/Sarang). Unfortunateley that had too a slight irregularity, to get rid of it both rectangles need an offset of ½ point, therefore the version of (20:00,4 March 2011) is larger: 437 bytes.

Very similar is Zeichen 625-11.svg, its Sodipodi version of 5598 bytes became 5200 bytes smaller by manual coding. It has only three red strokes but more complicated relations with its framing. It can be asked whether the background should be white instead of transparent.


Most SVG files in the category Chevrons could be disgarbeged, with remarkable reductions of file sizes.


Compare also Italian left (Sodipodi) with Italian right (manual).