Sound System - Revision history

Lucubro: -WIP

2012-02-22T13:08:48Z

-WIP

← Older revision		Revision as of 13:08, 22 February 2012
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	<small>'''[[GSoC_2011\|GSoC 2011]] > Sound System'''</small>		<small>'''[[GSoC_2011\|GSoC 2011]] > Sound System'''</small>

	~~{{User:Lucubro/WIP}}~~

	<div style="float:right; margin-left:20px; margin-bottom:15px">__TOC__</div>		<div style="float:right; margin-left:20px; margin-bottom:15px">__TOC__</div>
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	=== Sounds associated to behaviours/actions of monsters ===		=== Sounds associated to behaviours/actions of monsters ===
	Like he is angry and plays the angry sound. These sounds can be played by using the factory sound system described above.		Like he is angry and plays the angry sound. These sounds can be played by using the factory sound system described above.

	~~=== Sounds for each weapon and attack ===~~
	~~If you attack with a sword you should hear the sound of a sword.~~

	=== Random sounds from environment ===		=== Random sounds from environment ===
	Buzzes of flies, water for rivers, wind and so on so forth.		Buzzes of flies, water for rivers, wind and so on so forth. These sounds can be played using emitters.


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	== Optional extensions ==		== Optional extensions ==
	These things (or part of them) will be done during the GSoC coding time only time permitting. Otherwise they can still be included in the next GSoC or implemented by developers.		These things (or part of them) will be done during the GSoC coding time only time permitting. Otherwise they can still be included in the next GSoC or implemented by developers.
			* Sounds for each weapon and attack: if you attack with a sword you should hear the sound of a sword.
	* Add ability to limit number of channels. The idea is to be able to limit the amount of sounds played at the same time coming from different sources. In the same areas you can have rivers, monsters, wind, and even the player clicking on the UI.		* Add ability to limit number of channels. The idea is to be able to limit the amount of sounds played at the same time coming from different sources. In the same areas you can have rivers, monsters, wind, and even the player clicking on the UI.
	* Special actions to do when particular sound types are being played (for example reducing all other sounds/music volume)		* Special actions to do when particular sound types are being played (for example reducing all other sounds/music volume)

Lucubro: /* Sounds in factories */

2012-02-06T20:55:32Z

Sounds in factories

← Older revision		Revision as of 20:55, 6 February 2012
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	* TIME_START = 0;		* TIME_START = 0;
	* TIME_END = 24;		* TIME_END = 24;
	* FALLBACK_STATE = -1;		* FALLBACK_STATE = UNDEFINED_STATE;
	* FALLBACK_PROBABILITY = 0.0;		* FALLBACK_PROBABILITY = 0.0;

	==== Example ====		==== Example ====
	We want to make a monster emits different sounds when it is in different states. The states are peace, combat and died. Moreover we want the monster to emit a sound when it ~~charge~~ the player:		We want to make a monster emits different sounds when it is in different states. The states are peace, combat and died. Moreover we want the monster to emit a sound when it charges the player:

	<nowiki><ENTITY FACTORY="monster_factory" MAX_RANGE="30.0">		<nowiki><ENTITY FACTORY="monster_factory" MAX_RANGE="30.0">
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	<!-- Dead state -->		<!-- Dead state -->
	<STATE ID="5" PROBABILITY="0~~.1" DELAY="10~~" FALLBACK_PROBABILITY="1.0">		<STATE ID="5" PROBABILITY="1.0" FALLBACK_PROBABILITY="1.0">
	<RESOURCE NAME="dead_sound_1" />		<RESOURCE NAME="dead_sound_1" />
	<RESOURCE NAME="dead_sound_2" />		<RESOURCE NAME="dead_sound_2" />
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	</ENTITY></nowiki>		</ENTITY></nowiki>

	Let's examine it in details.		Let's examine it in details. The first state is the peace state. Its ID is 1 (the same as the PEACE mode in psModeMessage::playerMode). PROBABILITY="0.1" means that there is a probability of 0.1 that the monster will play one of the resources '''in a second'''; moreover DELAY is set to 10 seconds so (on average) the monster will play once every 20 seconds (for 10 seconds the monster is surely silent because of the delay, the remaining 10 seconds are random and associated to the probability). All the other parameters not explicitly written take the default value as explained in the [[Sound System#Optional attributes\|section above]].

			The second state is associated to the charge event. The ID is 2. If we take a look at [http://planeshift.svn.sourceforge.net/viewvc/planeshift/trunk/src/common/net/messages.h psModeMessage::playerMode] we notice that this is the ID for the combat state. The probability is 1.0 so the sound is played as soon as the monster enter in combat mode. Since FALLBACK_PROBABILITY is 1.0 the monster will change its state to the one with ID="100" right after the sound has been played. The state with ID="100" is defined at the end and its the state associated with the combat state. By using the fallback state we can make the monster emit a sound just when it enters in combat mode (in this case a shout at the beginning of the combat) and then '''change the set of resources that are played''' (in this case to the resources in the state 100, the fight sounds).

			The third state is the dead state. As you can see the FALLBACK_PROBABILITY is set to 1.0 but there is not the FALLBACK_STATE! In this way the entity will change its state to UNDEFINED_STATE (see default values above) and won't play anything else. The monster thus will play a sound as soon as it will be killed and then it will change its state and it won't play anything else.

	==== The common sector ====		==== The common sector ====

Lucubro: /* Sounds in factories */

2012-02-06T18:40:10Z

Sounds in factories

@@ Line 507: / Line 507: @@
 * FALLBACK_STATE = -1;
 * FALLBACK_PROBABILITY = 0.0;
 ==== The common sector ====

Lucubro: /* Sounds in factories */

2011-12-27T00:23:30Z

Sounds in factories

← Older revision		Revision as of 00:23, 27 December 2011
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	==== Optional attributes ====		==== Optional attributes ====
	There are other optional attributes that can be used in the tag to configure better an entity.		There are other optional attributes that can be used in the tag to configure better an entity. Below there is a complete example with all the attributes that can be used and their explanation.
			<ENTITY FACTORY="name_of_the_factory" MIN_RANGE="0.5" MAX_RANGE="10.5">
			<STATE ID="1" PROBABILITY="0.5" DELAY="20" VOLUME="1.0" TIME_START="9" TIME_END="21" FALLBACK_STATE="2" FALLBACK_PROBABILITY="0.5">
			<RESOURCE NAME="name_of_the_sound_to_play_1" />
			<RESOURCE NAME="name_of_the_sound_to_play_2" />
			<RESOURCE NAME="name_of_the_sound_to_play_3" />
			</STATE>

			<STATE ID="2" PROBABILITY="1.0" DELAY="20" VOLUME="1.0" TIME_START="0" TIME_END="24">
			<RESOURCE NAME="name_of_the_sound_to_play_1" />
			</STATE>
			</ENTITY>

	* MIN_RANGE: the maximum distance at which the sound is heard with the maximum volume.		* MIN_RANGE: the maximum distance at which the sound is heard with the maximum volume.
			* PROBABILITY: the probability that one of the resources is played in a second.
			* DELAY: the interval of time in seconds during which the factory (mesh) cannot play any sound once the previous sound is finished.
	* VOLUME: the general volume of the sound (it will decrease with the distance).		* VOLUME: the general volume of the sound (it will decrease with the distance).
	* TIME_START: the time of the day in hours when the factory (mesh) can play the sound when it's in that state.		* TIME_START: the time of the day in hours when the factory (mesh) can play the sound when it's in that state.
	* TIME_END: the time of the day in hours when the factory (mesh) can't play the sound when it's in that state.		* TIME_END: the time of the day in hours when the factory (mesh) can't play the sound when it's in that state.
	* ~~DELAY~~: the ~~interval~~ of ~~time in seconds during which~~ the ~~factory (mesh) cannot play any sound once the previous sound~~ is ~~finished~~.		* FALLBACK_STATE: the ID of the state that is activated after this one has been activated with a probability per second given by ''FALLBACK_PROBABILITY''.
	* ~~PROBABILITY~~: the probability that ~~one of~~ the ~~resources is played in a second.~~		* FALLBACK_PROBABILITY: the probability per second that the entity state changes into the one give by ''FALLBACK_STATE''.

	~~A complete example with all~~ the ~~possible attribute for a factory entity:~~

	~~<ENTITY FACTORY="name_of_the_factory" STATE="1" RESOURCE="name_of_the_sound_to_play" STARTING_RESOURCE="name_of_the_sound_to_play_on_transition"~~
	~~PROBABILITY="0.5" MAX_RANGE="10.5" MIN_RANGE="0.5" VOLUME="1~~.~~0" TIME_START="9" TIME_END="21" DELAY_AFTER="20">~~

	~~for a mesh entity it is very similar but with the MESH attribute instead of FACTORY:~~

	~~<ENTITY MESH="name_of_the_mesh" STATE="1" RESOURCE="name_of_the_sound_to_play" STARTING_RESOURCE="name_of_the_sound_to_play_on_transition"~~
	~~PROBABILITY="0.5" MAX_RANGE="10.5" MIN_RANGE="0.5" VOLUME="1.0" TIME_START="9" TIME_END="21" DELAY_AFTER="20">~~

	The optional attributes if not given assume their default values that are:		The optional attributes, if not given, assume their default values that are:
	* MIN_RANGE = 0.0;		* MIN_RANGE = 0.0;
			* PROBABILITY = 1.0;
			* DELAY = 0;
	* VOLUME = 1.0;		* VOLUME = 1.0;
	* TIME_START = 0;		* TIME_START = 0;
	* TIME_END = 24;		* TIME_END = 24;
	* ~~DELAY_AFTER~~ = 0;		* FALLBACK_STATE = -1;
			* FALLBACK_PROBABILITY = 0.0;

	==== The common sector ====		==== The common sector ====
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	==== Ambiguities and priorities ====		==== Ambiguities and priorities ====
	When a ~~factory (mesh) entity~~ is defined more than once for the same ~~state~~, only the first one is picked up. All the other ones are ignored.		When a state with the same ID is defined more than once for the same factory (mesh) entity, only the first one is picked up. All the other ones are ignored.

	In summary the sound for a mesh can be specified in four ways: a mesh entity in its sector, a factory entity in its sector (that defines the sound also for all the others meshes produced by its factory), a mesh entity in the common sector and a factory entity in the common sector. These four ways have a different priority: the mesh entities in the current sector have the maximum priority and the factory entities in the common sector the minimum one. The complete priority order order is the following:		In summary the sound for a mesh can be specified in four ways: a mesh entity in its sector, a factory entity in its sector (that defines the sound also for all the others meshes produced by its factory), a mesh entity in the common sector and a factory entity in the common sector. These four ways have a different priority: the mesh entities in the current sector have the maximum priority and the factory entities in the common sector the minimum one. The complete priority order order is the following:

Lucubro: /* Sounds in factories */

2011-12-27T00:13:05Z

Sounds in factories

← Older revision		Revision as of 00:13, 27 December 2011
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	==== The ENTITY tag ====		==== The ENTITY tag ====
	A sound can be associated to a mesh factory or a mesh by ~~inserting~~ the tag <nowiki><ENTITY /></nowiki> in an xml document that describe an area (currently these documents are located in ''/art/soundlib.zip/areas''). There are two types of entities: a '''factory entity''' and a '''mesh entity'''. The first one associates a sound to a factory, the second one to a mesh. Here there are two example that explain how to create an entity:		A sound can be associated to a mesh factory or a mesh by using the tag <nowiki><ENTITY /></nowiki> in an xml document that describe an area (currently these documents are located in ''/art/soundlib.zip/areas''). There are two types of entities: a '''factory entity''' and a '''mesh entity'''. The first one associates a sound to a factory, the second one to a mesh. Here there are two example that explain how to create an entity:

	<ENTITY FACTORY="name_of_the_factory" STATE="1" RESOURCE="name_of_the_sound_to_play" ~~PROBABILITY="0.5" MAX_RANGE="10.5"~~>		<ENTITY FACTORY="name_of_the_factory" MAX_RANGE="10.5">
			<STATE ID="1">
			<RESOURCE NAME="name_of_the_sound_to_play" />
			</STATE>
			</ENTITY>

	<ENTITY MESH="name_of_the_mesh" ~~STATE~~="1" ~~STARTING_RESOURCE~~="~~name_of_the_sound_to_play_on_transition" PROBABILITY=~~"~~0.5" MAX_RANGE~~="~~10.5~~">		<ENTITY MESH="name_of_the_mesh" MAX_RANGE="10.5">
			<STATE ID="1">
			<RESOURCE NAME="name_of_the_sound_to_play" />
			</STATE>
			</ENTITY>

	In these two examples there are all the mandatory attributes of the ENTITY TAG:		In these two examples there are all the mandatory attributes and elements of the ENTITY TAG:
	* ~~<u>~~One and only one~~</u>~~ attribute between FACTORY and MESH that contains the name of the factory/mesh that you want to play the sound. If both those attributes are given, ~~or if~~ no one of them is specified, the tag is just ignored.		* '''One and only one''' attribute between ''FACTORY'' and ''MESH'' that contains the name of the factory/mesh that you want to play the sound. If ''FACTORY'' is specified the entity is considered a factory entity, if ''MESH'' is given it is considered a mesh entity. If both those attributes are given, only the attribute ''MESH'' is considered. If no one of them is specified the tag is just ignored.
	* ~~<u>~~One~~</u>~~ attribute STATE. The state is used to determine in which situation the factory (mesh) will play the sound. For example a factory called "rat" can be associated to a calm peep when it is in a normal state and to a more aggressive noise when it enters in combat. The states used by the client are those in the enum [http://planeshift.svn.sourceforge.net/viewvc/planeshift/trunk/src/common/net/messages.h psModeMessage::playerMode].		* '''One''' attribute ''MAX_RANGE'' that specifies the maximum distance at which the sound can be heard.
	* ~~<u>~~At least one~~</u>~~ attribute ~~between RESOURCE and STARTING_RESOURCE~~. ~~RESOURCE~~ gives the name of the sound that must be played randomly during the period of time in which the factory (mesh) is in the given state. ~~STARTING_RESOURCE is the name of the sound that must be played when the factory (mesh) enters the given state. STARTING_RESOURCE~~ can be ~~used~~ for ~~example to make a monster emit the last cry~~ when ~~it enters~~ the ~~''DEAD'' state. If no one of these two attributes is given the tag is just ignored.~~		* '''At least one''' child tag ''STATE'' with '''one''' attribute ''ID''. ''ID'' must be non-negative. The state is used to determine in which situation the factory (mesh) will play the sound. For example a factory called "rat" can be associated to a calm peep when it is in a normal state and to a more aggressive noise when it enters in combat. There can be an unlimited number of state for each entity. The states used by the client are those in the enum [http://planeshift.svn.sourceforge.net/viewvc/planeshift/trunk/src/common/net/messages.h psModeMessage::playerMode].
	* <u>One</u> attribute PROBABILITY that gives the probability that the sound indicated by the attribute RESOURCE is played in a ~~second. Note that the~~ sound ~~in STARTING_RESOURCE is '''always''' played at the beginning~~, ~~no matter~~ of the ~~probability.~~		* '''At least one''' child tag ''RESOURCE'' with '''one''' attribute ''NAME''. ''NAME'' gives the name of the sound that must be played randomly during the period of time in which the factory (mesh) is in the given state. There can be an unlimited number of resource for each state; when the entity plays a sound, it picks randomly one of the given resources.
	* <u>One</u> attribute MAX_RANGE that specifies the maximum distance at which the sound can be heard.

	==== Optional attributes ====		==== Optional attributes ====
	There are other optional attributes that can be used in the tag to configure better an entity.		There are other optional attributes that can be used in the tag to configure better an entity.
	* MIN_RANGE: the distance at which the sound is heard with the ~~highest~~ volume.		* MIN_RANGE: the maximum distance at which the sound is heard with the maximum volume.
	* VOLUME: the general volume of the sound (it will ~~vary~~ with the distance).		* VOLUME: the general volume of the sound (it will decrease with the distance).
	* TIME_START: the time in hours when the factory (mesh) ~~starts to~~ play ~~this~~ sound.		* TIME_START: the time of the day in hours when the factory (mesh) can play the sound when it's in that state.
	* TIME_END: the time in hours when the factory (mesh) ~~stops to~~ play ~~this~~ sound.		* TIME_END: the time of the day in hours when the factory (mesh) can't play the sound when it's in that state.
	* ~~DELAY_AFTER~~: the interval of time in seconds during which the factory (mesh) cannot play any sound once the previous sound is finished.		* DELAY: the interval of time in seconds during which the factory (mesh) cannot play any sound once the previous sound is finished.
			* PROBABILITY: the probability that one of the resources is played in a second.

	A complete example with all the possible attribute for a factory entity:		A complete example with all the possible attribute for a factory entity:

Lucubro: /* Instrument */

2011-11-21T22:42:57Z

Instrument

← Older revision		Revision as of 22:42, 21 November 2011
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	<instruments>		<instruments>
	<instrument name="guitar" polyphony="3~~" volume="1.0~~" volume="1.0" min_dist="1.0" max_dist="50.0">		<instrument name="guitar" polyphony="3" volume="1.0" min_dist="1.0" max_dist="50.0">
	<note resource="E2" step="E" alter="0" octave="2"/>		<note resource="E2" step="E" alter="0" octave="2"/>
	<note resource="A3" step="A" alter="0" octave="3"/>		<note resource="A3" step="A" alter="0" octave="3"/>

Lucubro: suggested images for buttons

2011-09-06T21:05:31Z

suggested images for buttons

← Older revision		Revision as of 21:05, 6 September 2011
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	[[File:PawsMusicWindow1.jpg\|thumb\|500px\|Figure 1: The GUI used to create musical sheets in "edit mode"]]		[[File:PawsMusicWindow1.jpg\|thumb\|500px\|Figure 1: The GUI used to create musical sheets in "edit mode"]]
	In Figure 1 is represented the GUI to create musical sheet. The toolbar presents many buttons, in order from left to right:		In Figure 1 is represented the GUI to create musical sheet. The toolbar presents many buttons, in order from left to right:
	# Edit mode: toggle on-off the edit mode (where the user can edit the sheet).		# Edit mode '''(toggle)''': toggle on-off the edit mode (where the user can edit the sheet).
	# Play/Stop '''(toggle)''': used to play/stop the musical sheet.		# Play/Stop '''(toggle)''': used to play/stop the musical sheet.
	# Load: load a sheet from a file on the hard disk.		# Load: load a sheet from a file on the hard disk.
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	# BPM: change the BPM of the song.		# BPM: change the BPM of the song.
	# Rest '''(toggle)''': when down rests are inserted instead of notes.		# Rest '''(toggle)''': when down rests are inserted instead of notes.
	# The third group of buttons are the duration buttons and they decide the duration of the note/rest. In order they are: sixteenth, eighth, quarter, half and whole. '''The last one is a toggle button''' and when down a dot is inserted near the note to multiply its duration by 1.5 times.		# The third group of buttons are the duration buttons and they decide the duration of the note/rest. '''They are all toggle buttons'''. In order they are: sixteenth, eighth, quarter, half and whole. '''The last one is a toggle button too''' and when down a dot is inserted near the note to multiply its duration by 1.5 times.
	# The fourth group of buttons are the alteration buttons, in order flat, natural and sharp. '''They are all toggle buttons'''.		# The fourth group of buttons are the alteration buttons, in order flat, natural and sharp. '''They are all toggle buttons'''.
	# Delete chord: delete the selected chord.		# Delete chord: delete the selected chord.
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	'''Toggle buttons''' need 2 images (the up button image and the down one).		'''Toggle buttons''' need 2 images (the up button image and the down one).

			==== Suggested images ====
			For toggle buttons (with the exception of the Play/Stop button) it would be nice to have a shaded background version of the button when it is down.
			* Play/Stop '''(toggle)''': a play symbol when the button is off, a stop symbol when the button is on.
			* Load: I think that the given image is enough, it's the same that the sketch interface so the user is already acquainted with it.
			* Save: I think that the given image is enough, it's the same that the sketch interface so the user is already acquainted with it.
			* Change title: I think that the given image is enough, it's the same that the sketch interface so the user is already acquainted with it.
			* Tonality: something like [http://en.wikipedia.org/wiki/File:C-sharp-major_a-sharp-minor.svg this]. You can avoid to draw the clef.
			* Switch double staff: a [http://en.wikipedia.org/wiki/Modern_musical_symbols#Lines staff].
			* Meter: a fraction 4/4 like [http://en.wikipedia.org/wiki/File:Characteristic_rock_drum_pattern.png here]
			* BPM: just write "BPM".
			* Rest '''(toggle)''': a quarter rest (e.g. the third symbol in [http://en.wikipedia.org/wiki/File:Quarter_notes_and_rest.svg this image].
			* Duration buttons: a note with the corresponding duration, take a look [http://en.wikipedia.org/wiki/Note_value here] to find the symbol associate to each note value.
			* Dot button: a [http://en.wikipedia.org/wiki/Dotted_note dot].
			* Alteration buttons: a [http://en.wikipedia.org/wiki/Flat_(music) flat] for the first button, a [http://en.wikipedia.org/wiki/Natural_(music) natural] for the second one and a [http://en.wikipedia.org/wiki/Sharp_(music) sharp] for the third one.
			* Delete chord: a note with a cross on it.
			* Delete measure: a measure with a cross on it.
			* Start repeat '''(toggle)''': a line with a colon on its right.
			* End repeat '''(toggle)''': a line with a colon on its left like [http://en.wikipedia.org/wiki/File:Repeatsign.svg here].
			* Ending '''(toggle)''': something like [http://commons.wikimedia.org/wiki/File:2nd_ending_2.png this] (the upper line doesn't have to be so long).

	=== Network communications part ===		=== Network communications part ===

Lucubro: typo

2011-08-26T08:16:42Z

typo

← Older revision		Revision as of 08:16, 26 August 2011
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	=== GUI part ===		=== GUI part ===
	----		----
	[[File:PawsMusicWindow1.jpg\|thumb\|500px\|Figure 1: The GUI to create musical sheets in "edit mode"]]		[[File:PawsMusicWindow1.jpg\|thumb\|500px\|Figure 1: The GUI used to create musical sheets in "edit mode"]]
	In Figure 1 is represented the GUI to create musical sheet. The toolbar presents many buttons, in order from left to right:		In Figure 1 is represented the GUI to create musical sheet. The toolbar presents many buttons, in order from left to right:
	# Edit mode: toggle on-off the edit mode (where the user can edit the sheet).		# Edit mode: toggle on-off the edit mode (where the user can edit the sheet).
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	# Delete chord: delete the selected chord.		# Delete chord: delete the selected chord.
	# Delete measure: delete the selected measure.		# Delete measure: delete the selected measure.
	[[File:PawsMusicWindow2.jpg\|thumb\|500px\|Figure 2: The GUI to ~~reate~~ musical sheets with double staff]]		[[File:PawsMusicWindow2.jpg\|thumb\|500px\|Figure 2: The GUI used to create musical sheets with double staff]]
	# Insert note '''(toggle)''': insert a note where clicked.		# Insert note '''(toggle)''': insert a note where clicked.
	# Insert measure: insert a note before the selected measure.		# Insert measure: insert a note before the selected measure.

Lucubro: /* GUI part */

2011-08-26T08:15:27Z

GUI part

← Older revision		Revision as of 08:15, 26 August 2011
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	In Figure 1 is represented the GUI to create musical sheet. The toolbar presents many buttons, in order from left to right:		In Figure 1 is represented the GUI to create musical sheet. The toolbar presents many buttons, in order from left to right:
	# Edit mode: toggle on-off the edit mode (where the user can edit the sheet).		# Edit mode: toggle on-off the edit mode (where the user can edit the sheet).
	# Play/Stop: used to play/stop the musical sheet.		# Play/Stop '''(toggle)''': used to play/stop the musical sheet.
	# Load: load a sheet from a file on the hard disk.		# Load: load a sheet from a file on the hard disk.
	# Save: save the sheet into a file on the hard disk.		# Save: save the sheet into a file on the hard disk.

Lucubro: /* Network communications part */

2011-08-11T15:03:45Z

Network communications part

← Older revision		Revision as of 15:03, 11 August 2011
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	'''Toggle buttons''' need 2 images (the up button image and the down one).		'''Toggle buttons''' need 2 images (the up button image and the down one).

			=== Network communications part ===
			----
			When a player click the Play Song button, the song manager send the compressed musical sheet to the server asking for playing it. The server then does the following things:
			* checks that the player is the owner of the musical sheet;
			* checks that the player has an instrument equipped;
			* determines with which instrument the player should play the song;
			* computes the error probabilities depending on the player skills with that instrument;
			* send a psPlaySongMessage containing the score, the instrument to use and the error probabilities to the player and all the near players.
			The client receive all these parameters and translate the score into music.

			Note that the server can only compute the error probabilities but it's the client that applies it. This is necessary because the server doesn't control directly the produced sound but it has only the musical sheet in an XML format. Another approach to this problem would be letting the server change the played musical sheet depending on the error probabilities. This would still be uneffective because:
			* the score is saved on the server compressed so to be edited it should be decompressed first (time consuming).
			* the score should be parsed and edited (very time consuming).
			* the client would still be hackable by changing the received musical sheet with the one represented in pawsMusicWindow that is error-free.

			Thus, any attempt to let the server decide how to apply the error probability to the song's execution is useless. Nevertheless this is not a big deal:
			* the computed error probability affects only what the player hear but not the sucess/fail of the operation (that is handled by the server).
			* even if the player hacked his client to set the error probability to 0, all the near players would hear that song with mistakes.

	== Optional extensions ==		== Optional extensions ==