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| author | Mattias Andrée <maandree@kth.se> | 2017-07-11 20:26:04 +0200 |
|---|---|---|
| committer | Mattias Andrée <maandree@kth.se> | 2017-07-11 20:26:04 +0200 |
| commit | d91c5e12a53a33d50a5a0cef41255ae5b39bd55e (patch) | |
| tree | 83420390a9571678b762aa72ad305702d46221c7 | |
| parent | blind-spiral-gradient: fix -a (diff) | |
| download | blind-d91c5e12a53a33d50a5a0cef41255ae5b39bd55e.tar.gz blind-d91c5e12a53a33d50a5a0cef41255ae5b39bd55e.tar.bz2 blind-d91c5e12a53a33d50a5a0cef41255ae5b39bd55e.tar.xz | |
blind-spiral-gradient: add -s
Signed-off-by: Mattias Andrée <maandree@kth.se>
| -rw-r--r-- | man/blind-spiral-gradient.1 | 12 | ||||
| -rw-r--r-- | src/blind-spiral-gradient.c | 10 |
2 files changed, 21 insertions, 1 deletions
diff --git a/man/blind-spiral-gradient.1 b/man/blind-spiral-gradient.1 index e91688f..954adcc 100644 --- a/man/blind-spiral-gradient.1 +++ b/man/blind-spiral-gradient.1 @@ -3,6 +3,8 @@ blind-spiral-gradient - Generate a video with a spiral gradient .SH SYNOPSIS .B blind-spiral-gradient +[-s +.IR spirals ] [-al] -w .I width @@ -100,6 +102,16 @@ Create a spiral that gones anticlockwise. .B -l Create a logarithmic spiral. .TP +.BR -s " "\fIspirals\fP +Draw +.I spirals +spirals +going out the specified centre instead of +just one spiral. The spirals are uniformly +distributed. +.I spirals +can be any non-zero real number. +.TP .BR -w " "\fIwidth\fP The width of the video, in pixels. .TP diff --git a/src/blind-spiral-gradient.c b/src/blind-spiral-gradient.c index 4cf5937..5d80bef 100644 --- a/src/blind-spiral-gradient.c +++ b/src/blind-spiral-gradient.c @@ -1,10 +1,11 @@ /* See LICENSE file for copyright and license details. */ #include "common.h" -USAGE("[-al] -w width -h height") +USAGE("[-s spirals] [-al] -w width -h height") static int anticlockwise = 0; static int logarithmic = 0; +static double spirals = 1; static size_t width = 0; static size_t height = 0; static int with_params; @@ -58,6 +59,7 @@ static int with_vector; y2 -= y1;\ u = atan2(y2, x2);\ b = sqrt(x2 * x2 + y2 * y2);\ + b *= spirals;\ if (logarithmic)\ b = log(b);\ b /= pow(2 * (TYPE)M_PI, e);\ @@ -96,6 +98,7 @@ static int with_vector; r = pow(r / b, ep);\ r = (r - v) / (2 * (TYPE)M_PI);\ }\ + r = mod(r, 1 / (TYPE)spirals) * (TYPE)spirals + r - mod(r, (TYPE)1);\ buf[ptr][0] = buf[ptr][1] = buf[ptr][2] = buf[ptr][3] = r;\ if (++ptr == ELEMENTSOF(buf)) {\ ewriteall(STDOUT_FILENO, buf, sizeof(buf), "<stdout>");\ @@ -123,6 +126,11 @@ main(int argc, char *argv[]) case 'l': logarithmic = 1; break; + case 's': + spirals = etolf_flag('s', UARGF()); + if (!spirals) + eprintf("the value of -s must not be 0"); + break; case 'w': width = etozu_flag('w', UARGF(), 1, SIZE_MAX); break; |