Mercurial > hg > octave-nkf
annotate scripts/image/brighten.m @ 10400:b14fd5116c29
Ensure that 'limits' is a 2 or 4 vector, and that 'fn' is a function
| author | Soren Hauberg <hauberg@gmail.com> |
|---|---|
| date | Fri, 05 Mar 2010 14:29:47 -0800 |
| parents | 1bf0ce0930be |
| children | ec34c7acd057 |
| rev | line source |
|---|---|
| 8920 | 1 ## Copyright (C) 1999, 2000, 2007, 2009 Kai Habel |
| 6788 | 2 ## |
| 3 ## This file is part of Octave. | |
| 4 ## | |
| 5 ## Octave is free software; you can redistribute it and/or modify it | |
| 6 ## under the terms of the GNU General Public License as published by | |
| 7016 | 7 ## the Free Software Foundation; either version 3 of the License, or (at |
| 8 ## your option) any later version. | |
| 6788 | 9 ## |
| 10 ## Octave is distributed in the hope that it will be useful, but | |
| 11 ## WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 12 ## MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| 13 ## General Public License for more details. | |
| 14 ## | |
| 15 ## You should have received a copy of the GNU General Public License | |
| 7016 | 16 ## along with Octave; see the file COPYING. If not, see |
| 17 ## <http://www.gnu.org/licenses/>. | |
| 6788 | 18 |
| 19 ## -*- texinfo -*- | |
| 20 ## @deftypefn {Function File} {@var{map_out} =} brighten (@var{map}, @var{beta}) | |
| 6792 | 21 ## @deftypefnx {Function File} {@var{map_out} =} brighten (@var{h}, @var{beta}) |
| 6788 | 22 ## @deftypefnx {Function File} {@var{map_out} =} brighten (@var{beta}) |
|
9051
1bf0ce0930be
Grammar check TexInfo in all .m files
Rik <rdrider0-list@yahoo.com>
parents:
8920
diff
changeset
|
23 ## Darkens or brightens the given colormap. If the @var{map} argument |
|
1bf0ce0930be
Grammar check TexInfo in all .m files
Rik <rdrider0-list@yahoo.com>
parents:
8920
diff
changeset
|
24 ## is omitted, the function is applied to the current colormap. The first |
| 6788 | 25 ## argument can also be a valid graphics handle @var{h}, in which case |
| 26 ## @code{brighten} is applied to the colormap associated with this handle. | |
| 27 ## | |
| 28 ## Should the resulting colormap @var{map_out} not be assigned, it will be | |
| 29 ## written to the current colormap. | |
| 30 ## | |
| 31 ## The argument @var{beta} should be a scalar between -1 and 1, | |
| 32 ## where a negative value darkens and a positive value brightens | |
| 33 ## the colormap. | |
| 34 ## @seealso{colormap} | |
| 35 ## @end deftypefn | |
| 36 | |
| 37 function Rmap = brighten (m, beta) | |
| 38 h = -1; | |
| 39 if (nargin == 1) | |
| 40 beta = m; | |
| 41 m = colormap; | |
| 42 h = gcf (); | |
| 43 elseif (nargin == 2) | |
| 44 if (ishandle (m)) | |
| 45 h = m; | |
| 46 m = get (h, "colormap"); | |
| 8507 | 47 elseif (! is_matrix (m) || size (m, 2) != 3) |
| 8664 | 48 error ("brighten: first argument must be an Nx3 matrix or a handle"); |
| 6788 | 49 endif |
| 50 else | |
| 51 print_usage (); | |
| 52 endif | |
| 53 | |
| 8507 | 54 if (! isscalar (beta) || beta <= -1 || beta >= 1) |
| 8664 | 55 error ("brighten: beta must be a scalar in the range (-1,1)"); |
| 6788 | 56 endif |
| 57 | |
| 58 if (beta > 0) | |
| 59 gamma = 1 - beta; | |
| 60 else | |
| 61 gamma = 1 / (1 + beta); | |
| 62 endif | |
| 63 | |
| 64 if (nargout == 0) | |
| 65 if (ishandle (h)) | |
| 66 set (h, "colormap", m .^ gamma); | |
| 67 else | |
| 68 colormap (m .^ gamma); | |
| 69 endif | |
| 70 else | |
| 71 Rmap = m .^ gamma; | |
| 72 endif | |
| 73 | |
| 74 endfunction |