Conky Lua & Cairo Troubleshooting

[wlourf]

re the blur... no luck yet, or at least nothing I know how to implement.

i was thinking along the line of seeing if you can export the data from cairo to imlib2...
you can use imlib2 to apply a blur filter to an image... or even export the cairo data to an image file and then display and blur the image with imlib2

but i havn't found out how to do that yet

Hi MrPeachy !
To export data from cairo to imlib, I think you have to export cairo to a png file and import png in imlib.
Look at theses functions in lua :

cairo_surface_write_to_png()
imlib_load_image()

Maybe there is another way, but at least it works, I used this method for my "calendar wheel" script if you 're looking for an example, it's here.

But how do you blur an image with imlib ??

Thanks

[mrpeachy]

I thought I had read about a blur filter with imlib2... but maybe it was something else:
heres one place that mentions it:

http://asbradbury.org/projects/lua-imlib2/doc/
search for blur... says
img:blur(radius)

Blurs the image. A radious value of 0 has no effect. 1 and above determine the blur matrix radius that determines how much to blur the image.

but now im not sure that this might require the lua-imlib2 package created by the author.

Or you could do your own "blur" effect, by calling multiple instances of the same image, altering their alpha value and overlaying them with slightly altered positions like this:

goes to

or another way to achieve a blur like effect would be to scale the image down, save it and then scale it back up again like this:

not as nice but quick and easy.

i havnt used imlib2 so i dont know if it can do the above either

[wlourf]

Hi all,

I need some advice for calling C code in a Lua script.

I am back with my attempt to draw an audio equalizer widget with conky (does this already exist ?)
This work is based on this widget (Impulse) for gnome : https://launchpad.net/impulse.bzr

So, if I can't get something faster, I will post the code here.

Actually the Lua script call a python script which call the Impulse.so file.

So I think Lua should call directly the Impulse.so file but I have no skills in C and it's where problems begin ! First I read this tuto

The conky is :

# -- Conky settings -- #
background no
update_interval 1

cpu_avg_samples 2
net_avg_samples 2

override_utf8_locale yes

double_buffer yes
no_buffers yes

text_buffer_size 2048
imlib_cache_size 0

# -- Window specifications -- #

own_window yes
#own_window_type desktop
own_window_transparent yes
#own_window_hints undecorate,sticky,skip_taskbar,skip_pager,below
own_window_title with lua

border_inner_margin 0
border_outer_margin 0

minimum_size 200 300

alignment tm
gap_x 10
gap_y 0

# -- Graphics settings -- #
draw_shades no
draw_outline no
draw_borders no
draw_graph_borders no

# -- Text settings -- #
use_xft yes
xftfont Santana:size=12
xftalpha 0.8

uppercase no

default_color FFFFFF


# -- Lua Load -- #
# SET THE PATH TO THE SCRIPT HERE
lua_load ~/scripts/equa1.1c/equalizer.lua
lua_draw_hook_pre main3

TEXT
with lua
cpu0 ${cpu cpu0}
cpu1 ${cpu cpu1}
update=0.1
mem ${mem}
up. ${updates}

The Lua code to load the Impulse.so is :

require 'cairo'
function conky_main3()

    package.cpath = "./?.so"
    require "Impulse"
    if conky_window == nil then return end
    
    local cs = cairo_xlib_surface_create(conky_window.display, conky_window.drawable, conky_window.visual, conky_window.width, conky_window.height)
    
    cr = cairo_create(cs)

    cairo_destroy(cr)
    cairo_surface_destroy(cs)
        
end

After installing the packages libfftw3 and libpulsedev
I modified the Impulse.c file at the beginning :

/*
 *
 *+  Copyright (c) 2009 Ian Halpern
 *@  http://impulse.ian-halpern.com
 *
 *   This file is part of Impulse.
 *
 *   Impulse is free software: you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation, either version 3 of the License, or
 *   (at your option) any later version.
 *
 *   Impulse is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with Impulse.  If not, see <http://www.gnu.org/licenses/>.
 */
/* 
wlourf 16.02.2010
added the 4 first lines
install libfftw3 libpulsedev package
*/

#include "lua/lua.h"
#include "lua/lualib.h"
#include "lua/lauxlib.h"
#include "stdio.h"

#include <pulse/pulseaudio.h>
#include <assert.h>
#include <string.h>
#include <fftw3.h>
#include <math.h>

#define CHUNK 1024

static const long fft_max[] = { 12317168L, 7693595L, 5863615L, 4082974L, 5836037L, 4550263L, 3377914L, 3085778L, 3636534L, 3751823L, 2660548L, 3313252L, 2698853L, 2186441L, 1697466L, 1960070L, 1286950L, 1252382L, 1313726L, 1140443L, 1345589L, 1269153L, 897605L, 900408L, 892528L, 587972L, 662925L, 668177L, 686784L, 656330L, 1580286L, 785491L, 761213L, 730185L, 851753L, 927848L, 891221L, 634291L, 833909L, 646617L, 804409L, 1015627L, 671714L, 813811L, 689614L, 727079L, 853936L, 819333L, 679111L, 730295L, 836287L, 1602396L, 990827L, 773609L, 733606L, 638993L, 604530L, 573002L, 634570L, 1015040L, 679452L, 672091L, 880370L, 1140558L, 1593324L, 686787L, 781368L, 605261L, 1190262L, 525205L, 393080L, 409546L, 436431L, 723744L, 765299L, 393927L, 322105L, 478074L, 458596L, 512763L, 381303L, 671156L, 1177206L, 476813L, 366285L, 436008L, 361763L, 252316L, 204433L, 291331L, 296950L, 329226L, 319209L, 258334L, 388701L, 543025L, 396709L, 296099L, 190213L, 167976L, 138928L, 116720L, 163538L, 331761L, 133932L, 187456L, 530630L, 131474L, 84888L, 82081L, 122379L, 82914L, 75510L, 62669L, 73492L, 68775L, 57121L, 94098L, 68262L, 68307L, 48801L, 46864L, 61480L, 46607L, 45974L, 45819L, 45306L, 45110L, 45175L, 44969L, 44615L, 44440L, 44066L, 43600L, 57117L, 43332L, 59980L, 55319L, 54385L, 81768L, 51165L, 54785L, 73248L, 52494L, 57252L, 61869L, 65900L, 75893L, 65152L, 108009L, 421578L, 152611L, 135307L, 254745L, 132834L, 169101L, 137571L, 141159L, 142151L, 211389L, 267869L, 367730L, 256726L, 185238L, 251197L, 204304L, 284443L, 258223L, 158730L, 228565L, 375950L, 294535L, 288708L, 351054L, 694353L, 477275L, 270576L, 426544L, 362456L, 441219L, 313264L, 300050L, 421051L, 414769L, 244296L, 292822L, 262203L, 418025L, 579471L, 418584L, 419449L, 405345L, 739170L, 488163L, 376361L, 339649L, 313814L, 430849L, 275287L, 382918L, 297214L, 286238L, 367684L, 303578L, 516246L, 654782L, 353370L, 417745L, 392892L, 418934L, 475608L, 284765L, 260639L, 288961L, 301438L, 301305L, 329190L, 252484L, 272364L, 261562L, 208419L, 203045L, 229716L, 191240L, 328251L, 267655L, 322116L, 509542L, 498288L, 341654L, 346341L, 451042L, 452194L, 467716L, 447635L, 644331L, 1231811L, 1181923L, 1043922L, 681166L, 1078456L, 1088757L, 1221378L, 1358397L, 1817252L, 1255182L, 1410357L, 2264454L, 1880361L, 1630934L, 1147988L, 1919954L, 1624734L, 1373554L, 1865118L, 2431931L };

static int16_t buffer[ CHUNK / 2 ], snapshot[ CHUNK / 2 ];
static size_t buffer_index = 0;

static pa_context *context = NULL;
static pa_stream *stream = NULL;
static pa_threaded_mainloop* mainloop = NULL;
static pa_io_event* stdio_event = NULL;
static pa_mainloop_api *mainloop_api = NULL;
static char *stream_name = NULL, *client_name = NULL, *device = NULL;

static pa_sample_spec sample_spec = {
    .format = PA_SAMPLE_S16LE,
    .rate = 44100,
    .channels = 2
};

static pa_stream_flags_t flags = 0;

static pa_channel_map channel_map;
static int channel_map_set = 0;


/* A shortcut for terminating the application */
static void quit( int ret ) {
    assert( mainloop_api );
    mainloop_api->quit( mainloop_api, ret );
}

static void get_source_info_callback( pa_context *c, const pa_source_info *i, int is_last, void *userdata ) {

    if ( is_last || device != NULL )
        return;

    assert(i);

    // snprintf(t, sizeof(t), "%u", i->monitor_of_sink);

    if ( i->monitor_of_sink != PA_INVALID_INDEX ) {

        device = pa_xstrdup( i->name );

        if ( ( pa_stream_connect_record( stream, device, NULL, flags ) ) < 0 ) {
            fprintf(stderr, "pa_stream_connect_record() failed: %s\n", pa_strerror(pa_context_errno(c)));
            quit(1);
        }
    }
}

/* This is called whenever new data may is available */
static void stream_read_callback(pa_stream *s, size_t length, void *userdata) {
    const void *data;
    assert(s);
    assert(length > 0);

    if (stdio_event)
        mainloop_api->io_enable(stdio_event, PA_IO_EVENT_OUTPUT);

    if (pa_stream_peek(s, &data, &length) < 0) {
        fprintf(stderr, "pa_stream_peek() failed: %s\n", pa_strerror(pa_context_errno(context)));
        quit(1);
        return;
    }

    assert(data);
    assert(length > 0);

    int excess = buffer_index * 2 + length - ( CHUNK );

    if ( excess < 0 ) excess = 0;

    memcpy( buffer + buffer_index, data, length - excess );
    buffer_index += ( length - excess ) / 2;

    if ( excess ) {
        memcpy( snapshot, buffer, buffer_index * 2 );
        buffer_index = 0;
    }

    pa_stream_drop(s);
}


static void context_state_callback(pa_context *c, void *userdata) {

    switch (pa_context_get_state(c)) {
        case PA_CONTEXT_CONNECTING:
        case PA_CONTEXT_AUTHORIZING:
        case PA_CONTEXT_SETTING_NAME:
            break;
        case PA_CONTEXT_READY:
            assert(c);
            assert(!stream);

            if (!(stream = pa_stream_new(c, stream_name, &sample_spec, channel_map_set ? &channel_map : NULL))) {
                fprintf(stderr, "pa_stream_new() failed: %s\n", pa_strerror(pa_context_errno(c)));
                quit(1);
            }

            pa_stream_set_read_callback(stream, stream_read_callback, NULL);

            pa_operation_unref( pa_context_get_source_info_list( c, get_source_info_callback, NULL ) );

            break;
        case PA_CONTEXT_TERMINATED:
            quit(0);
            break;

        case PA_CONTEXT_FAILED:
        default:
            fprintf(stderr, "Connection failure: %s\n", pa_strerror(pa_context_errno(c)));
            quit(1);
    }
}

void im_stop (void) {

    pa_threaded_mainloop_stop( mainloop );

    //printf( "exit\n" );
}

double *im_getSnapshot( int fft ) {

    static double magnitude[ CHUNK / 4 ];

    if ( ! fft ) {
        int i;
        for ( i = 0; i < CHUNK / 2; i += sample_spec.channels ) {
            magnitude[ i / sample_spec.channels ] = 0;
            int j;
            for ( j = 0; j < sample_spec.channels; j++ )
                magnitude[ i / sample_spec.channels ] += fabs( ( (double) snapshot[ i + j ] / ( pow( 2, 16 ) / 2 ) ) / sample_spec.channels );
        }
    } else {

        double *in;
        fftw_complex *out;
        fftw_plan p;

        in = (double*) malloc( sizeof( double ) * ( CHUNK / 2 ) );
        out = (fftw_complex*) fftw_malloc( sizeof( fftw_complex ) * ( CHUNK / 2 ) );

        if ( snapshot != NULL ) {
            int i;
            for ( i = 0; i < CHUNK / 2; i++ ) {
                in[ i ] = (double) snapshot[ i ];
            }
        }

        p = fftw_plan_dft_r2c_1d( CHUNK / 2, in, out, 0 );

        fftw_execute( p );

        fftw_destroy_plan( p );

        if ( out != NULL ) {
            int i;
            for ( i = 0; i < CHUNK / 2 / sample_spec.channels; i++ ) {
                magnitude[ i ] = (double) sqrt( pow( out[ i ][ 0 ], 2 ) + pow( out[ i ][ 1 ], 2 ) ) / (double) fft_max[ i ];
                if ( magnitude[ i ] > 1.0 ) magnitude[ i ] = 1.0;
            }
        }

        free( in );
        fftw_free(out);
    }

    return magnitude; // PyString_FromStringAndSize( (char *) snapshot, CHUNK );
}


void im_start ( void ) {

    // Pulseaudio
    int r;
    char *server = NULL;

    client_name = pa_xstrdup( "cimpulse" );
    stream_name = pa_xstrdup( "cimpulse" );

    // Set up a new main loop

    if ( ! ( mainloop = pa_threaded_mainloop_new( ) ) ) {
        fprintf( stderr, "pa_mainloop_new() failed.\n" );
        return;
    }

    mainloop_api = pa_threaded_mainloop_get_api( mainloop );

    r = pa_signal_init( mainloop_api );
    assert( r == 0 );

    /*if (!(stdio_event = mainloop_api->io_new(mainloop_api,
                                             STDOUT_FILENO,
                                             PA_IO_EVENT_OUTPUT,
                                             stdout_callback, NULL))) {
        fprintf(stderr, "io_new() failed.\n");
        goto quit;
    }
    
    // create a new connection context
    if ( ! ( context = pa_context_new( mainloop_api, client_name ) ) ) {
        fprintf( stderr, "pa_context_new() failed.\n" );
        return;
    }

    pa_context_set_state_callback( context, context_state_callback, NULL );

    /* Connect the context */
    pa_context_connect( context, server, 0, NULL );

    // pulseaudio thread
    pa_threaded_mainloop_start( mainloop );

    return;
}

and I compiled the impulse.c with this command :

gcc -o Impulse.so -shared Impulse.c

whitout errors

BUT, when I run my conky

conky -c conkyrc

I get this error :

Conky: llua_do_call: function conky_main3 execution failed: error loading module 'Impulse' from file './Impulse.so':
./Impulse.so: undefined symbol: pa_xstrdup

all pulseaudio variables are not recognized !

So, as I don't know nothing in C, what do you think about this error ?

Thanks!

[ianimal]

Wlourf,

As the creator of Impulse let me explain the source structure. impulse.so is the python bindings for the libimpulse.so library. Impulse.h, Impulse.c are the source code files for libimpulse.so, not impulse.so. The source code for impulse.so is impulsemodule.c. impulse.so uses the library libimpulse.so. You should not add any Lua code to Impulse.h or Impulse.c. Instead you should create a new file and follow the structure of impulsemodule.c to create a lua version using the lua c api, like the link you sent me here http://www.wellho.net/mouth/1844_Cal...rst-HowTo.html.

To build libimpulse.so use something like the following:

gcc -pthread -Wall -fPIC -c Impulse.c -o libimpulse.o
gcc -pthread -lpulse -lfftw3 -shared -Wl,-soname,libimpulse.so -fPIC libimpulse.o -o libimpulse.so
rm *.o

To build impulse.so (the python bindings) use something like the following:

gcc -pthread -fno-strict-aliasing -DNDEBUG -g -fwrapv -O2 -Wall -Wstrict-prototypes -fPIC -I/usr/include/python2.6 -c impulsemodule.c -o impulse.o
gcc -pthread -shared -Wl,-O1 -Wl,-Bsymbolic-functions -L. -limpulse -Wl,-rpath,. impulse.o -o impulse.so
rm *.o

*Note: -Wl,-rpath,. just allows for the dynamic linker to search for libraries in the current local path. You can also just move libimpulse.so to /usr/lib and remove -Wl,-rpath,. from the build command.

I hope this helps as a jumping off point.

[wlourf]

Thanks Ian,
That seems to be toooooooo complicated for me actually ...
I will return to my little drawnings and stay with the python stuff for the moment !


Edit 28 Feb 2010 :
With the help of Ian, I made a nice conky for his Impulse library, it's on this post.

[olgmen]

Hello everyone

I olgmen from Russia

Sorry for the mistakes, I do not know much English language and writing with an electronic translator.

I wrote a small script printed to the window conky expanding inscription MAIL. But I do not know how to connect the test mail. If a script to insert checks with conkyEmail, it is continuous, constant checking email

Text of script

--[[ Conky Widgets by olgmen (2010)

This widget displays the window conky expanding inscription MAIL!!!

lua_load ~/scripts/text_mail.lua
lua_draw_hook_pre widgets

]]


require 'cairo'

function text()

        local x = 0
        local y = 200
        local w=conky_window.width
        local h = 50

        local extents = cairo_text_extents_t:create()
-- назначаем шрифт

        cairo_select_font_face(cr, "PT Sans", CAIRO_FONT_SLANT_NORMAL, CAIRO_FONT_WEIGHT_BOLD)

-- font size

        size = 10

        alpha = 0.6

        local updates=conky_parse('${updates}')

        if updates == nil then updates = 0 end

            update_num=tonumber(updates)

                if (update_num % 6 == 0) then
                
                    if updates_num == nil then updates_num = 0 end

                    reset_num=update_num
        
                end

                if (reset_num >0)then

                    timer_num=update_num-reset_num

                    cairo_set_font_size(cr, size*timer_num)
                    cairo_text_extents(cr, "MAIL !!!", extents)
                    cairo_set_source_rgba(cr, 1, 0, 0, alpha+timer_num/10)
                    cairo_move_to(cr, x + w/2 - extents.x_advance/2, y + 0.5*h - extents.y_bearing/2)
                    cairo_show_text(cr, "MAIL !!!")

                end
end

    function conky_widgets()
        if conky_window == nil then return end
        local cs = cairo_xlib_surface_create(conky_window.display, conky_window.drawable, conky_window.visual, conky_window.width, conky_window.height)

    cr = cairo_create (cs)
    text()
    cairo_destroy (cr)

end

how to make check-mail

Thank
and good day

[wlourf]

how to make check-mail

Thank
and good day

hello olgmen, I don't use this function but did you try fetchmail , the documentation says :

mails (mailbox) (interval) Mail count in the specified mailbox or your mail spool if not. Both mbox and maildir type mailboxes are supported. You can use a program like fetchmail to get mails from some server using your favourite protocol. See also new_mails.

aybe this like is more sure (conkyEmail) : http://conky.linux-hardcore.com/?page_id=846

[wlourf]

Hi!

When we call a conkyrc with an alsolute path like this :

conky -c /home/wlourf/scripts/conkyrc

How can we get the path of the conky, or the path of a Lua script called by the conky.
It's for the audio analyser widget, it works fine when it is called from conkyrc's path but not when called from an another path because the Lua runs python like this :

impulse_pipe = io.popen('python impulse.py ' .. fft , "r")

and doesn't find impulse.py

Thanks

[dk75]

Hi!

When we call a conkyrc with an alsolute path like this :

conky -c /home/wlourf/scripts/conkyrc

How can we get the path of the conky, or the path of a Lua script called by the conky.
It's for the audio analyser widget, it works fine when it is called from conkyrc's path but not when called from an another path because the Lua runs python like this :

impulse_pipe = io.popen('python impulse.py ' .. fft , "r")

and doesn't find impulse.py

Thanks

I don't know the proper way but I do know some improper way

First of all, there is some better way to call external command (I found it durring "lua wait command" search):

function os.capture(cmd, raw)
	local f = assert(io.popen(cmd, 'r'))
	local s = assert(f:read('*a'))
	f:close()
	if raw then return s end
	s = string.gsub(s, '^%s+', '')
	s = string.gsub(s, '%s+$', '')
	s = string.gsub(s, '[\n\r]+', ' ')
	return s
end

and then, the improper way - test it:

conkyrc

background no
update_interval 1
total_run_times 1
own_window yes
own_window_type override
own_window_transparent yes
own_window_colour black
own_window_hints undecorated,below,sticky,skip_taskbar,skip_pager
double_buffer yes
minimum_size 0 0
maximum_width 0
imlib_cache_size 0
lua_load $HOME/.conky/lua/test04.lua
lua_draw_hook_pre conky_main
TEXT

test04.lua

do

function os.capture(cmd, raw)
	local f = assert(io.popen(cmd, 'r'))
	local s = assert(f:read('*a'))
	f:close()
	if raw then return s end
	s = string.gsub(s, '^%s+', '')
	s = string.gsub(s, '%s+$', '')
	s = string.gsub(s, '[\n\r]+', ' ')
	return s
end

lua_script_dir = os.capture('find ~ -depth -mount -nowarn -name test04.lua -type f -print -quit 2>/dev/null |awk -F"/" \'{gsub($NF,"");print}\'')

impulse_command = os.capture('find ~ -depth -mount -nowarn -name impulse.py -type f -print -quit 2>/dev/null')

fft = 'you must define it here'

function conky_main()
	impulse_pipe = os.capture('python ' .. impulse_command .. ' ' .. fft)
	print (lua_script_dir)
	print (impulse_pipe)
end

end

[wlourf]

I don't know the proper way but I do know some improper way

First of all, there is some better way to call external command (I found it durring "lua wait command" search):

function os.capture(cmd, raw)
    local f = assert(io.popen(cmd, 'r'))
    local s = assert(f:read('*a'))
    f:close()
    if raw then return s end
    s = string.gsub(s, '^%s+', '')
    s = string.gsub(s, '%s+$', '')
    s = string.gsub(s, '[\n\r]+', ' ')
    return s
end

and then, the improper way - test it:

conkyrc

background no
update_interval 1
total_run_times 1
own_window yes
own_window_type override
own_window_transparent yes
own_window_colour black
own_window_hints undecorated,below,sticky,skip_taskbar,skip_pager
double_buffer yes
minimum_size 0 0
maximum_width 0
imlib_cache_size 0
lua_load $HOME/.conky/lua/test04.lua
lua_draw_hook_pre conky_main
TEXT

test04.lua

do

function os.capture(cmd, raw)
    local f = assert(io.popen(cmd, 'r'))
    local s = assert(f:read('*a'))
    f:close()
    if raw then return s end
    s = string.gsub(s, '^%s+', '')
    s = string.gsub(s, '%s+$', '')
    s = string.gsub(s, '[\n\r]+', ' ')
    return s
end

lua_script_dir = os.capture('find ~ -depth -mount -nowarn -name test04.lua -type f -print -quit 2>/dev/null |awk -F"/" \'{gsub($NF,"");print}\'')

impulse_command = os.capture('find ~ -depth -mount -nowarn -name impulse.py -type f -print -quit 2>/dev/null')

fft = 'you must define it here'

function conky_main()
    impulse_pipe = os.capture('python ' .. impulse_command .. ' ' .. fft)
    print (lua_script_dir)
    print (impulse_pipe)
end

end

Hmmpf, that's nice ! I finally found another (proper?) way to find the script's path using conky_config from Lua API, and I didn't managed to get the path with your script

function conky_main()

    local s=conky_config
    local pos=(s:reverse(s)):find("/")
    if pos==nil then pos=0 end
    
    lua_script_dir= s:sub(1 ,#s-pos+1)
    print (lua_script_dir)
    fft = 1
    if impulse_pipe == nil then
        --impulse_pipe = io.popen('python ' .. lua_script_dir .. 'impulse.py ' .. fft , "r")
        impulse_pipe = os.capture('python ' .. lua_script_dir .. 'impulse.py ' .. ' ' .. fft)
    end 
    
end

Anyway, it works BUT not, it doesn't work!

Impulse.py is called, yes, but the python script needs to load the 'impulse' shared library with

import impulse

but doesn't find it because it's not in the PATH.
I can pass the path to impulse to python with an argument but after I didn't find a way to load the shared library.
I tried that for example :

imp.load_dynamic('impulse', os.path.join(sys.argv[2], 'impulse.so'))

but without success, so if you have some ideas again, it will be nice !