- This wiki is out of date, use the continuation of this wiki instead
Process
From FenixWiki
Revision as of 00:06, 9 May 2007 (edit) Sandman (Talk | contribs) m ← Previous diff |
Current revision (23:57, 8 August 2008) (edit) (undo) Sandman (Talk | contribs) m (→Statement) |
||
(8 intermediate revisions not shown.) | |||
Line 2: | Line 2: | ||
[[category:reserved]] | [[category:reserved]] | ||
[[category:language]] | [[category:language]] | ||
+ | [[category:basic statement]] | ||
- | + | [[Basic statements|'''Up to Basic Statements''']] | |
+ | ---- | ||
== Definition == | == Definition == | ||
+ | |||
+ | === Statement === | ||
+ | '''Process''' <name>([<parameters>])<br> | ||
+ | ['''Public''' | ||
+ | :<public variables>] | ||
+ | ['''Private''' | ||
+ | :<private variables>] | ||
+ | '''Begin''' | ||
+ | :<main code> | ||
+ | ['''OnExit''' | ||
+ | :<OnExit code>] | ||
+ | '''End''' | ||
+ | |||
+ | Process is a reserved word used to start the code of a process. If ''name'' is ''Main'', that process will be started at the start of the program (see [[Program]]). | ||
+ | |||
+ | === Concept === | ||
A process is a [[subroutine]] to which one or more of the following apply: | A process is a [[subroutine]] to which one or more of the following apply: | ||
*it receives [[parameter]]s | *it receives [[parameter]]s | ||
Line 21: | Line 39: | ||
*The [[smallbro]] variable of the processes called by the father immediately before the new process was called (updated). | *The [[smallbro]] variable of the processes called by the father immediately before the new process was called (updated). | ||
*The [[son]] and smallbro variables are also defined of the new process, but do not yet carry values. | *The [[son]] and smallbro variables are also defined of the new process, but do not yet carry values. | ||
+ | |||
+ | When there are no more processes alive, the program ends. | ||
== Example == | == Example == | ||
<pre> | <pre> | ||
- | Process SpaceShip( | + | Process SpaceShip( int x, int y, int angle, int maxspeed, int maxturnspeed) |
- | Private | + | Public // Declare public variables here (Fenix 0.86 and up) |
+ | Private // Declare private variables here | ||
int speed; | int speed; | ||
- | Begin | + | Begin // Start the main processcode |
+ | graph = new_map(20,20,8); | ||
+ | map_clear(0,graph,rgb(0,255,255)); | ||
Loop | Loop | ||
speed+=key(_up)*(speed<maxspeed)-key(_down)*(speed>-maxspeed); | speed+=key(_up)*(speed<maxspeed)-key(_down)*(speed>-maxspeed); | ||
Line 34: | Line 57: | ||
frame; | frame; | ||
End | End | ||
- | End | + | OnExit // Start the exit code (Fenix 0.90.2 and up) |
+ | unload_map(0,graph); | ||
+ | End // End the main processcode | ||
</pre> | </pre> | ||
Now one can call this process for example by doing the following. | Now one can call this process for example by doing the following. | ||
<pre> | <pre> | ||
- | + | Process Main() | |
- | + | ||
Begin | Begin | ||
- | | + | SpaceShip(100,100,0,20,5000); |
- | | + | Repeat |
- | | + | frame; |
+ | Until(key(_ESC)) | ||
+ | let_me_alone(); | ||
End | End | ||
</pre> | </pre> | ||
- | Used in example: [[key]](), [[advance]](), [[ | + | Used in example: [[new_map]](), [[map_clear]](), [[key]](), [[advance]](), [[unload_map]](), [[let_me_alone]](), [[Process]], [[Begin]], [[End]], [[Loop]], [[Repeat]], [[graph]], [[angle]] |
+ | |||
+ | And when the SpaceShip process ends - because the code of it reached the End or something sent an [[s_kill]] [[signal]] - the [[OnExit]] code starts. In this example it will unload the memory used for the created [[graphic]]. If there is no OnExit code, the process will just end. | ||
This will make a SpaceShip with a cyan coloured block, able to move around the screen. | This will make a SpaceShip with a cyan coloured block, able to move around the screen. |
Current revision
Contents |
[edit] Definition
[edit] Statement
Process <name>([<parameters>])
[Public
- <public variables>]
[Private
- <private variables>]
Begin
- <main code>
[OnExit
- <OnExit code>]
End
Process is a reserved word used to start the code of a process. If name is Main, that process will be started at the start of the program (see Program).
[edit] Concept
A process is a subroutine to which one or more of the following apply:
- it receives parameters
- it acts on the parameters
- it processes data located elsewhere
In addition to these possibilities, a process always has a frame; statement. The difference between a function and a process is a process is treated as a separate thread. This means one can't let a process return a value like a function, as the father process continues its code as well, as soon as the process hits a frame; statement or when the code is done. When that happens, the process 'returns' its ProcessID and continues the code (in the next frame).
In earlier Fenix versions (2005 and earlier) there is no difference in syntax, however, a process is treated like a function when there is no frame; statement in the code.
When the frame; statement is reached in the code, a number of other local variables are defined or updated not only of the new process, but also of related processes. These are:
- The father variable of the new process.
- The son variable of the father process (updated).
- The bigbro variable of the new process.
- The smallbro variable of the processes called by the father immediately before the new process was called (updated).
- The son and smallbro variables are also defined of the new process, but do not yet carry values.
When there are no more processes alive, the program ends.
[edit] Example
Process SpaceShip( int x, int y, int angle, int maxspeed, int maxturnspeed) Public // Declare public variables here (Fenix 0.86 and up) Private // Declare private variables here int speed; Begin // Start the main processcode graph = new_map(20,20,8); map_clear(0,graph,rgb(0,255,255)); Loop speed+=key(_up)*(speed<maxspeed)-key(_down)*(speed>-maxspeed); angle+=(key(_left)-key(_right))*maxturnspeed; advance(speed); frame; End OnExit // Start the exit code (Fenix 0.90.2 and up) unload_map(0,graph); End // End the main processcode
Now one can call this process for example by doing the following.
Process Main() Begin SpaceShip(100,100,0,20,5000); Repeat frame; Until(key(_ESC)) let_me_alone(); End
Used in example: new_map(), map_clear(), key(), advance(), unload_map(), let_me_alone(), Process, Begin, End, Loop, Repeat, graph, angle
And when the SpaceShip process ends - because the code of it reached the End or something sent an s_kill signal - the OnExit code starts. In this example it will unload the memory used for the created graphic. If there is no OnExit code, the process will just end.
This will make a SpaceShip with a cyan coloured block, able to move around the screen.