path: root/doc/pddp/all_about_messages.pd

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#X obj 407 2 pddp/pddplink http://puredata.info/dev/pddp -text pddp
;
#N canvas 14 48 428 289 What_is_a_message_in_Pd? 0;
#X obj 1 1 cnv 15 425 20 empty \$0-pddp.cnv.subheading empty 20 10
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#X text 7 1 What is a message in Pd?;
#X text 19 126 1) A selector \, which must be a symbol atom.[1];
#X text 19 243 [1] The exceptions to this are implicit float and list
messages. See the next subpatch for details.;
#X text 19 106 Messages in Pd are made up of the following components:
;
#X text 19 183 Messages divide into two groups: those with selectors
that have a predefined meaning and behavior in Pd \, and everything
else. See the other subpatches for more on how Pd processes messages.
;
#X text 19 36 Objects in Pd send each other various data in the form
of messages. Messages can transport all kinds of information: float
\, symbol \, and pointer atoms \, groups of floats and symbols \, etc.
Understanding how to build and work with messages is a key to understanding
Pd.;
#X text 19 146 2) Zero or more arguments \, which may be any atom type
that Pd can understand.;
#X restore 43 42 pd What_is_a_message_in_Pd?;
#X obj 43 183 pddp/pddplink all_about_atoms.pd;
#N canvas 19 160 428 264 User_defined_messages_in_Pd 0;
#X obj 1 1 cnv 15 425 20 empty \$0-pddp.cnv.subheading empty 20 10
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#X text 7 1 User-defined messages in Pd;
#X text 20 79 1) single selector messages - these are messages made
up of a single symbol atom \, like "set" \, "clear" \, or "flush".
;
#X text 20 37 User defined messages \, also referred to as "anythings"
\, are messages with selectors other than those predefined by Pd (listed
in the previous subpatch). These include:;
#X obj 20 231 pddp/pddplink all_about_lists_vs_anythings.pd;
#X text 20 212 For more information about "anythings" \, see:;
#X text 20 110 2) custom selector + 1 or more arguments - messages
with a custom selector followed by one or more atoms of any type. Examples
include "set 3 4 5" \, "threshold 30 74" \, and "foo bar 3 four".;
#X text 20 165 These messages are also referred to as meta-messages
\, selector series \, and anythings. (Additionally \, a message like
"foo 1 2 3" could be called a "foo message").;
#X restore 43 94 pd User_defined_messages_in_Pd;
#X obj 1 226 cnv 15 445 20 empty \$0-pddp.cnv.footer empty 20 12 0
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#N canvas 44 246 494 344 META 0;
#X text 12 105 HELP_PATCH_AUTHORS Dave Sabine \, May 5 \, 2003 . Jonathan
Wilkes revised the patch to conform to the PDDP template for Pd version
0.42.;
#X text 12 85 LIBRARY PDDP;
#X text 12 5 GENRE all_about_pd;
#X text 12 45 KEYWORDS needs_work;
#X text 12 25 NAME list float symbol;
#X text 12 65 DESCRIPTION message syntax in Pd;
#X restore 392 228 pd META;
#X obj 6 228 pddp/pddplink all_about.pd -text All About Pd;
#X text 42 153 Messages are made up of atoms. Make sure you understand
atoms before reading about messages.;
#N canvas 20 104 428 468 Distinguishing_Message_Types 0;
#X obj 1 1 cnv 15 425 20 empty \$0-pddp.cnv.subheading empty 20 10
1 18 -261106 -33289 0;
#X msg 23 72 foo;
#X msg 23 140 symbol foo;
#X symbolatom 22 378 10 0 0 0 - - -;
#X msg 22 254 symbol clear;
#X msg 46 310 clear;
#X text 109 260 like this one and pass it to the outlet after;
#X text 108 246 The [pipe] object will take a symbol message;
#X text 91 297 On the other hand \, the "clear" message tells the;
#X text 19 403 It's helpful to consider the following: if Pd didn't
make a distinction between "symbol clear" and "clear" \, how would
[pipe] know whether you want to send the word "clear" to the outlet
\, or trigger the "clear" function described above?;
#X text 90 312 [pipe] object to forget all stored message and;
#X text 90 327 refrain from outputting anything.;
#X obj 22 351 pipe s 3000;
#X text 95 351 <-- wait 3 seconds \, then output the message;
#X text 7 1 Understanding Message Types;
#X text 20 35 Remember that messages in Pd can consist of a single
symbol atom. Consider the following:;
#X text 19 201 This distinction is important: some objects \, for example
\, have one behavior for symbol messages \, and a different behavior
for custom messages.;
#X text 109 274 the specified duration (3 seconds).;
#X text 19 93 Above is a message with the selector "foo". You might
also refer to this as a custom message \, the symbol atom "foo" \,
or even a "foo message". The message has no arguments.;
#X text 19 159 Above is a message with the selector "symbol". The first
(and only) argument is "foo". This is a "symbol message" \, one of
Pd's built-in message types.;
#X connect 4 0 12 0;
#X connect 5 0 12 0;
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#X restore 43 120 pd Distinguishing_Message_Types;
#N canvas 24 124 428 150 Quick_Quiz! 0;
#X obj 1 1 cnv 15 425 20 empty \$0-pddp.cnv.subheading empty 3 12 0
14 -261106 -33289 0;
#X text 7 2 Messages- Related Objects;
#X msg 22 43 list quiz: What type of message is this?;
#X obj 22 99 bng 15 250 50 0 empty empty list 0 25 0 8 -262144 -1 -1
;
#X obj 63 99 bng 15 250 50 0 empty empty bang 0 25 0 8 -262144 -1 -1
;
#X obj 104 99 bng 15 250 50 0 empty empty float 0 25 0 8 -262144 -1
-1;
#X obj 146 99 bng 15 250 50 0 empty empty symbol 0 25 0 8 -262144 -1
-1;
#X obj 187 99 bng 15 250 50 0 empty empty secret 0 25 0 8 -262144 -1
-1;
#X obj 229 99 bng 15 250 50 0 empty empty none_of_the_above 0 25 0
8 -262144 -1 -1;
#X obj 22 70 route list bang float symbol secret;
#X text 276 42 <- Click to find out;
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#N canvas 0 0 878 627 old 0;
#X obj 433 459 route;
#X floatatom 113 135 5 0 0 1 "float" - -;
#X symbolatom 204 135 10 0 0 1 "symbol" - -;
#X obj 116 231 symbol;
#X symbolatom 116 278 0 0 0 0 - - -;
#X msg 125 255 word;
#X msg 116 213 test;
#X msg 99 191 symbol this;
#X text 190 190 set type directly;
#X text 157 255 does not work (check console messages);
#X floatatom 35 253 5 0 0 0 - - -;
#X msg 40 232 12;
#X msg 23 212 float 83;
#N canvas 534 126 490 340 Related_Objects 0;
#X obj 32 54 ftos;
#X obj 68 54 list2symbol;
#X text 23 22 data type conversion;
#X obj 155 55 tosymbol;
#X obj 219 55 fromsymbol;
#X obj 36 252 lister;
#X obj 34 98 atoi;
#X obj 30 138 list2int;
#X obj 94 137 l2i;
#X obj 96 163 a2l;
#X obj 29 164 any2list;
#X obj 158 138 list2symbol;
#X obj 158 159 symbol2list;
#X obj 247 138 l2s;
#X obj 247 158 s2l;
#X obj 123 252 list;
#X restore 447 604 pd Related_Objects;
#X text 407 245 Many objects cast the data they receive when they output
it:;
#X text 526 326 Some objects do not cast the data:;
#X obj 424 297 trigger anything;
#X msg 424 272 this is a list without a cast;
#X obj 424 320 print;
#X text 410 360 Some objects need to have the data explicitly declared
in order to handle it. These are mostly symbol handling objects.;
#X text 410 426 Objects which route data generally can handle explicitly
or implicitly defined data.;
#X obj 480 459 trigger;
#X obj 538 459 niagara;
#X obj 426 403 select;
#X obj 15 18 cnv 15 750 20 empty empty all_about_data_types 20 10 1
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#X obj 731 19 pddp/pddplink http://puredata.info/dev/pddp -text pddp
;
#X text 11 311 "anything";
#X text 11 427 "list";
#X text 11 413 "float";
#X text 11 454 "symbol";
#X text 11 400 "bang";
#X msg 111 359 anything 1 two three;
#X msg 262 359 one 2 3;
#X obj 167 442 bng 15 250 50 0 empty empty empty 0 -6 0 8 -262144 -1
-1;
#X obj 171 416 t a b f l p s;
#X obj 201 443 bng 15 250 50 0 empty empty empty 0 -6 0 8 -262144 -1
-1;
#X msg 264 393 list one 2 3;
#X msg 303 423 1 2 3;
#X text 17 55 atoms (basic data types):;
#X text 17 80 The basic data types are known as 'atoms' in Pd. "float"
and "symbol" atoms have 'atom boxes' for realtime display and control
from within a patch. "pointer" atoms are used for accessing data stored
in graphical data structures.;
#X obj 421 197 int;
#X obj 429 177 / 5.23;
#X floatatom 429 149 5 0 0 0 - - -;
#X floatatom 462 217 5 0 0 0 - - -;
#X floatatom 421 217 5 0 0 0 - - -;
#X obj 511 147 tosymbol;
#X obj 575 148 fromsymbol;
#X obj 658 147 list2symbol;
#X obj 662 189 ftos;
#X obj 617 56 symbol;
#X obj 580 100 int;
#X obj 699 56 pointer;
#X obj 440 100 bang;
#X obj 478 101 bng 15 250 50 0 empty empty empty 0 -6 0 8 -262144 -1
-1;
#X obj 499 56 float;
#X text 21 547 There a number of objects which are used for storing
messages \, or casting messages as a specific data type \, sometimes
converting from one data type to another. The right inlet on these
objects is stores that value \, which can be later output using a bang.
;
#X obj 608 100 lister;
#X text 540 57 aka;
#X obj 566 56 f;
#X obj 470 531 pddp/pddplink all_about_lists_vs_anythings.pd -text
all_about_lists_vs_anythings;
#X obj 470 552 pddp/pddplink all_about_symbol_construction.pd -text
all_about_symbol_construction;
#X obj 470 573 pddp/pddplink all_about_data_structures.pd -text all_about_data_structures
;
#X text 495 101 (aka [bng]);
#X text 23 324 "anything" allows anything to pass through unchanged.
It is not a data type tho.;
#X text 14 163 "symbols" need to be declared explicitly. "floats" do
not need to be declared explicitly \, but can be:;
#X text 173 232 casting as a "symbol";
#X text 21 529 CASTING AND STORAGE OBJECTS;
#X text 411 487 FOR MORE INFO:;
#X text 410 127 EXAMPLES OF CASTING;
#X text 405 56 atom objects:;
#X text 412 78 other data types:;
#X text 11 440 "pointer";
#X obj 44 480 trigger anything bang float list pointer symbol;
#X obj 44 500 bng 15 250 50 0 empty empty empty 0 -6 0 8 -262144 -1
-1;
#X obj 98 500 bng 15 250 50 0 empty empty empty 0 -6 0 8 -262144 -1
-1;
#X obj 154 499 bng 15 250 50 0 empty empty empty 0 -6 0 8 -262144 -1
-1;
#X obj 211 500 bng 15 250 50 0 empty empty empty 0 -6 0 8 -262144 -1
-1;
#X obj 267 499 bng 15 250 50 0 empty empty empty 0 -6 0 8 -262144 -1
-1;
#X obj 323 500 bng 15 250 50 0 empty empty empty 0 -6 0 8 -262144 -1
-1;
#X text 213 55 "float" \, "symbol" \, "pointer";
#N canvas 0 22 505 381 float/list 0;
#X msg 75 133 float 1 2 3;
#X text 34 22 FLOAT CONVERSION;
#X msg 95 187 list 1 2 3;
#X text 92 164 A list with multiple elements remains a list.;
#X text 43 59 A float with one element remains a float.;
#X text 72 106 A float with multiple elements remains a float but is
cut to one element.;
#X text 99 218 A list with one float element is converted to a float.
;
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#X obj 105 308 bng 15 250 50 0 empty empty float 0 21 1 9 -262144 -1
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#X obj 152 308 bng 15 250 50 0 empty empty symbol 0 21 1 9 -262144
-1 -1;
#X obj 200 308 bng 15 250 50 0 empty empty list 0 21 1 9 -262144 -1
-1;
#X obj 248 308 bng 15 250 50 0 empty empty UNDEFINED 0 21 1 9 -262144
-1 -1;
#X obj 57 286 route bang float symbol list;
#X obj 92 349 print FLOAT;
#X msg 50 81 float 3;
#X msg 106 239 list 2;
#X obj 188 349 print LIST;
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#X restore 445 506 pd float/list conversion;
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#X obj 125 268 bng 15 250 50 0 empty empty float 0 21 1 9 -262144 -1
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#X obj 172 268 bng 15 250 50 0 empty empty symbol 0 21 1 9 -262144
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#X obj 220 268 bng 15 250 50 0 empty empty list 0 21 1 9 -262144 -1
-1;
#X obj 268 268 bng 15 250 50 0 empty empty UNDEFINED 0 21 1 9 -262144
-1 -1;
#X msg 127 205 list;
#X msg 50 75 float;
#X msg 97 134 symbol;
#X text 31 21 EMPTY DATA TYPES;
#X obj 77 246 route bang float symbol list;
#X obj 73 326 print FLOAT;
#X obj 155 326 print SYMBOL;
#X text 120 184 An empty list is converted to a bang;
#X text 85 114 An empty "symbol" remains a empty "symbol".;
#X text 46 55 An empty "float" remains a "float" and is initialized
to 0;
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#X restore 636 506 pd empty data types;
#X text 568 604 updated for Pd version 0.38.4;
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#X restore 290 119 pd old;
#X obj 43 203 pddp/pddplink ../1.manual/x2.htm#s3.1;
#X text 194 202 <- fix this;
#N canvas 18 112 428 500 Predefined_and_implicit_messages_in_Pd 0;
#X obj 1 1 cnv 15 425 20 empty \$0-pddp.cnv.subheading empty 20 10
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#X text 7 1 Predefined messages in Pd;
#X text 20 131 2) symbol message - the selector "symbol" \, followed
by a single symbol atom.;
#X obj 1 274 cnv 15 425 20 empty \$0-pddp.cnv.subheading empty 20 10
1 18 -261106 -33289 0;
#X text 20 216 5) pointer message - the selector "pointer" \, followed
by a pointer atom.;
#X text 20 186 4) list - the selector "list" \, followed by two or
more atoms of any type (these are the elements of the list).;
#X text 20 166 3) bang message - the single selector "bang".;
#X text 20 246 6) signal - an audio signal;
#X text 7 274 Implicit float and list Messages;
#X text 20 37 In Pd \, when an object receives a message to an inlet
\, it looks at the selector to figure out what to do next. So that
objects can easily communicate with one another \, Pd has several predefined
messages:;
#X text 20 344 1) A single float atom has an implicit "float" selector.
;
#X msg 41 370 1;
#X msg 181 370 float 1;
#X text 71 370 is the same as...;
#X text 20 394 1) a message that starts with a float atom and is followed
by one or more atoms has an implicit "list" selector. Thus "1 2 3"
or "1 4 63" \, and even "1 foo fee four" are list messages.;
#X text 81 460 is the same as...;
#X msg 41 460 2 3 4;
#X msg 191 460 list 2 3 4;
#X text 20 97 1) float message - this message has the selector "float"
\, followed by a single float atom like 12 \, -4 \, or 1.8.;
#X text 20 309 Since numbers are used so often in Pd \, two shortcuts
are provided to make it easier to type and read them:;
#X restore 43 69 pd Predefined_and_implicit_messages_in_Pd;