1Pamgradient User Manual(0) Pamgradient User Manual(0)
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6 pamgradient - create a four-corner gradient PAM image
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10 pamgradient [-maxval=maxval] color-tl color-tr color-bl color-br width
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13 Minimum unique abbreviation of option is acceptable. You may use dou‐
14 ble hyphens instead of single hyphen to denote options. You may use
15 white space in place of the equals sign to separate an option name from
16 its value.
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21 This program is part of Netpbm(1).
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23 pamgradient creates an image of the specified dimensions width by
24 height which contains a smooth, two-dimensional gradient between the
25 specified colors of the four corners (from top left to bottom right).
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27 Specify the colors as described for the argument of the
28 pnm_parsecolor() library routine ⟨libnetpbm_image.html#colorname⟩ .
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30 If all four colors are gray values, pamgradient creates a grayscale
31 image (PAM tuple type GRAYSCALE). Otherwise, it creates a color image
32 (PAM tuple type RGB).
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36 In addition to the options common to all programs based on libnetpbm
37 (most notably -quiet, see
38 Common Options ⟨index.html#commonoptions⟩ ), pamgradient recognizes
39 the following command line option:
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43 -maxval=maxval
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46 maxval of the generated image. (See PAM(1) and PNM(1) specifi‐
47 cations).
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52 pamgradient(1), ppmmake(1), ppmrainbow(1), pgmramp(1), ppmpat(1),
53 pam(1), pnm(1)
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57 Only the top left corner of the generated image has exactly the speci‐
58 fied color. The color of the top right corner is a bit shifted to the
59 left, the bottom left corner a bit up, and the bottom right corner left
60 and up. This ensures nice transitions when combining adjacent (very
61 narrow) gradients, and doesn't play a role when the gradient butts
62 against a solid surface.
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64 This effect is created by the integer arithmetic used for the interpo‐
65 lation of the color values, and since it doesn't make a difference for
66 all practical purposes I might as well sell it as a feature.
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70 pamgradient was new in Netpbm 10.31 (December 2005).
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74 pamgradient was written by Daniel Haude in October 2005.
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77 This manual page was generated by the Netpbm tool 'makeman' from HTML
78 source. The master documentation is at
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80 http://netpbm.sourceforge.net/doc/pamgradient.html
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82netpbm documentation 21 October 2005 Pamgradient User Manual(0)