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diff --git a/ppmrough.html b/ppmrough.html index 7ecc343d..e31c4221 100644 --- a/ppmrough.html +++ b/ppmrough.html @@ -2,12 +2,13 @@ <html><head><title>Ppmrough User Manual</title></head> <body> <h1>ppmrough</h1> -Updated: 28 January 2022 +Updated: 20 August 2023 <br> <a href="#index">Table Of Contents</a> <h2>NAME</h2> -ppmrough - create PPM image of two colors with a ragged border between them +ppmrough - create PPM image of a single color rectangle with ragged edges on a +different color background <h2 id="synopsis">SYNOPSIS</h2> @@ -43,37 +44,27 @@ name and its value with white space instead of an equals sign. <p>This program is part of <a href="index.html">Netpbm</a>. -<p><b>ppmrough</b> generates a PPM image of the specified width, height, and -colors. <b>ppmrough</b> tiles the image into semi-rectangular regions with a -ragged borders between them. It calculates the fluctuations with -pseudo-random numbers. +<p><b>ppmrough</b> generates a PPM image of the specified width and height. + The image consists of a rectangle of the specified foreground color + surrounded by borders of the specified size and background color, except + that the boundary between the foreground rectangle and the borders is + ragged. The ragged effect is random. <p><b>ppmrough</b> writes the PPM image to Standard Output. <p>The maxval of the output image is 255 (You can change this with <b>pamdepth</b>). -<p>Use the options <b>-left</b> or <b>-right</b>, respectively, to -make vertical borders, and <b>-top</b> or <b>-bottom</b>, -respectively, to generate horizontal borders inside the image. Each of -these options needs an integer value <i>pixels</i> that determines the -average distance of the interior border to the related edge of the -image. You may combine the <b>-left</b>, <b>-right</b>, <b>-top</b>, -and <b>-bottom</b> options to generate an image with more than one -border. The algorithm ensures that you can concatenate two images -produced with the same (i.e. <b>-left</b>) value without dislocations. - -<p>You specify the dimensions of the generated image with the -<b>-width</b> and <b>-height</b> options. - -<p>Use the <b>-bg</b> and <b>-fg</b> options to set the background -(margin) color and the foreground (interior) color, respectively. If -you don't specify any of the <b>-left</b>, <b>-right</b>, <b>-top</b>, -and <b>-bottom</b> options, all pixels are set to foreground color. -The defaults are white foreground and black background. +<p>Use the options <b>-left</b> or <b>-right</b>, respectively, to make +vertical borders, and <b>-top</b> or <b>-bottom</b>, respectively, to generate +horizontal borders inside the image. The value of each of these options is +the minimum width of the border on that edge. Beyond that minimum, the width +at any given location on that edge is random, varying along the edge in a +fractal kind of way. + <p>Use the <b>-var</b> option to control the "raggedness" of -the border. The less its value is the smoother the border is. You +the border. The lower its value, the smoother the border is. You can initialize the pseudo-random generator with the <b>-init</b> option. @@ -88,51 +79,46 @@ Common Options</a>), <b>ppmrough</b> recognizes the following command line options: <dl compact> -<dt><b>-left=</b><i>pixels</i> - -<dd> Specifies the mean distance of the border from the left margin -(default: no border). -<dt><b>-right=</b><i>pixels</i> +<dt><b>-width=</b><i>pixels</i> -<dd>Specifies the mean distance of the border from the right margin -(default: no border). +<dd>This specifies the width of the image in pixels (default: 100). -<dt><b>-top=</b><i>pixels</i> +<dt><b>-height=</b><i>pixels</i> -<dd>Specifies the mean distance of the border from the top margin -(default: no border). +<dd>This specifies the height of the image in pixels (default: 100). +<dt><b>-left=</b><i>pixels</i> +<dt><b>-right=</b><i>pixels</i> +<dt><b>-top=</b><i>pixels</i> <dt><b>-bottom=</b><i>pixels</i> -<dd>Specifies the mean distance of the border from the bottom margin -(default: no border). - -<dt><b>-width=</b><i>pixels</i> - -<dd>Specifies the width of the image (default: 100). - -<dt><b>-height=</b><i>pixels</i> - -<dd>Specifies the height of the image (default: 100). +<dd>This option causes the program to create a left, right, top, or bottom +border, respectively, at least <i>pixels</i> pixels wide, varying randomly +beyond that. You may specify any combination of these. <dt><b>-bg=</b><i>colorspec</i> -<dd>Background color. <i>colorspec</i> is as described for the +<dd>This is the background color, i.e. the color of the +borders. <i>colorspec</i> is as described for the <a href="libnetpbm_image.html#colorname">argument of the <b>pnm_parsecolor()</b> library routine</a>. Default is black. <dt><b>-fg=</b><i>color</i> -<dd>Foreground color. <i>colorspec</i> is as described for the +<dd>This specifies the foreground color, i.e. the color of the center of the +mage -- everything but the borders. <i>colorspec</i> is as described for the <a href="libnetpbm_image.html#colorname">argument of the <b>pnm_parsecolor()</b> library routine</a>. Default is white. <dt><b>-var=</b><i>pixels</i> -<dd> Specifies the variance of the ragged border (default: 10). Must -be a positive integer. Set <i>pixels</i> to 1 to get a straight -border. +<dd>This specifies how ragged the borders are -- how much and how quickly its +width varies along the image edge. Its specific meaning is complex, but the +larger it is, the more the border varies. Zero means it does not vary at all +-- the edge of the foreground is straight. + +<p>This must be a nonnegative integer. The default is 10. <dt><b>-randomseed=</b><i>seed</i> |