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diff --git a/dumb/dumb-kode54/docs/deprec.txt b/dumb/dumb-kode54/docs/deprec.txt deleted file mode 100644 index 6ab7b60a..00000000 --- a/dumb/dumb-kode54/docs/deprec.txt +++ /dev/null @@ -1,281 +0,0 @@ -/* _______ ____ __ ___ ___
- * \ _ \ \ / \ / \ \ / / ' ' '
- * | | \ \ | | || | \/ | . .
- * | | | | | | || ||\ /| |
- * | | | | | | || || \/ | | ' ' '
- * | | | | | | || || | | . .
- * | |_/ / \ \__// || | |
- * /_______/ynamic \____/niversal /__\ /____\usic /| . . ibliotheque
- * / \
- * / . \
- * deprec.txt - Deprecated functions, why they / / \ \
- * were deprecated, and what to do | < / \_
- * instead. | \/ /\ /
- * \_ / > /
- * | \ / /
- * | ' /
- * \__/
- */
-
-
-**********************************************
-*** How the functions have been deprecated ***
-**********************************************
-
-
- GCC 3.1 and later provide a very useful attribute. The following:
-
- __attribute__((__deprecated__))
-
- when written alongside a function prototype, variable declaration or type
- definition, will result in a warning from GCC if any such part of the API
- is used. The warning will even tell you where the declaration is, and I
- have inserted comments by all the deprecated declarations, telling you
- what to do.
-
- Unfortunately, GCC 2.x and 3.0.x and MSVC do not have any means to
- deprecate things. The approach I have taken with these compilers is to
- avoid prototyping the deprecated parts of the API. This means you will get
- warnings and errors, and they won't be very helpful. If your program
- compiles, you may get strange crashes when you run it, since the compiler
- needs the declarations in order to make sure function calls are carried
- out correctly.
-
- If you would like the deprecated parts of the API to be declared, you can
- compile with the -DDUMB_DECLARE_DEPRECATED switch for GCC, or the
- -D"DUMB_DECLARE_DEPRECATED" switch for MSVC. This will be accepted by
- GCC 3.x but is unnecessary. Use this switch with other people's projects
- if necessary, but please make the effort to update your own projects to
- use the new API, as the deprecated parts may be removed in the future.
-
- The rest of this file explains why some parts of the API were deprecated,
- and how to adapt your code.
-
-
-**************************************
-*** What happened to DUH_RENDERER? ***
-**************************************
-
-
- The DUH_RENDERER struct was designed for rendering audio to an end-user
- format - 8-bit or 16-bit, signed or unsigned, with stereo samples
- interleaved. In order for it to do this, it was built on top of the
- hitherto undocumented DUH_SIGRENDERER struct, which rendered audio in
- DUMB's internal 32-bit signed format with channels (left/right) stored
- separately. The DUH_RENDERER struct contained a pointer to a
- DUH_SIGRENDERER struct, along with some other data like the position and
- number of channels.
-
- There were then some developments in the API. The DUH_SIGRENDERER struct
- also stored the position and the number of channels, so I decided to write
- functions for returning these. Suddenly there was no need to store them in
- the DUH_RENDERER struct. Before long, the DUH_RENDERER struct contained
- nothing but a pointer to a DUH_SIGRENDERER.
-
- I decided it would be a good idea to unify the structs. After all, there
- really is no difference between the data stored in each, and it would be
- easy to make duh_render(DUH_RENDERER *dr, ...) and
- duh_render_signal(DUH_SIGRENDERER *sr, ...) work on the same type of
- struct. (Note that duh_render_signal() is now deprecated too; see the next
- section.) It took some deliberation, but I decided I didn't want functions
- to be #defined (it prevents you from using these names for member
- functions in C++ classes), and that meant they had to be defined
- somewhere. Defining redundant functions is a source of bloat, inefficiency
- and general inelegance. After weighing things up, I decided it was better
- to deprecate the redundant functions and have people begin to use the more
- efficient versions, and eventually the redundant functions will be able to
- be removed.
-
- So why did I choose to keep the more complicated name, DUH_SIGRENDERER?
- The reason has to do with what DUMB will become in the future. Signals are
- an inherent part of the DUH struct and how .duh files will be constructed.
- It will be possible to have multiple signals in a single DUH struct, and
- you will be able to choose which one you want to play (this is the 'sig'
- parameter passed to duh_start_sigrenderer()). But don't hold your breath;
- we still have a long way to go before .duh files will start to appear...
-
-
-typedef DUH_SIGRENDERER DUH_RENDERER;
-
- Wherever you are using DUH_RENDERER in your program, simply replace it
- with DUH_SIGRENDERER. An automated (case-sensitive!) search and replace
- operation should get this done.
-
-
-DUH_RENDERER *duh_start_renderer(DUH *duh, int n_channels, long pos);
-
- Use duh_start_sigrenderer() instead. It takes an extra parameter, 'sig',
- which comes after 'duh' and before 'n_channels'; pass 0 for this. So an
- example would be, replace:
-
- sr = duh_start_renderer(duh, 2, 0);
-
- with:
-
- sr = duh_start_sigrenderer(duh, 0, 2, 0);
-
-
-int duh_renderer_get_n_channels(DUH_RENDERER *dr);
-long duh_renderer_get_position(DUH_RENDERER *dr);
-void duh_end_renderer(DUH_RENDERER *dr);
-
- These are easy enough to fix; all you have to do is replace 'renderer'
- with 'sigrenderer'. So the new functions are:
-
- int duh_sigrenderer_get_n_channels(DUH_SIGRENDERER *sigrenderer);
- long duh_sigrenderer_get_position(DUH_SIGRENDERER *sigrenderer);
- void duh_end_sigrenderer(DUH_SIGRENDERER *sigrenderer);
-
-
-Note that duh_render() has NOT been deprecated. It now uses DUH_SIGRENDERER
-instead of DUH_RENDERER, but its functionality is unchanged. You do not have
-to change calls to this function in any way.
-
-
-DUH_RENDERER *duh_renderer_encapsulate_sigrenderer(DUH_SIGRENDERER *sr);
-DUH_SIGRENDERER *duh_renderer_get_sigrenderer(DUH_RENDERER *dr);
-DUH_SIGRENDERER *duh_renderer_decompose_to_sigrenderer(DUH_RENDERER *dr);
-
- These functions did not exist in the last release of DUMB, so you are
- probably not using them, but they are included here for completeness. All
- you have to do here is unwrap the function, since the structs have been
- unified. So, for instance, replace:
-
- duh_renderer_encapsulate_sigrenderer(my_sigrenderer)
-
- with:
-
- my_sigrenderer
-
- Simple!
-
-
-AL_DUH_PLAYER *al_duh_encapsulate_renderer(DUH_RENDERER *dr,
- float volume, long bufsize, int freq);
-DUH_RENDERER *al_duh_get_renderer(AL_DUH_PLAYER *dp);
-DUH_RENDERER *al_duh_decompose_to_renderer(AL_DUH_PLAYER *dp);
-
- Again, these functions were not in the last release, so you probably
- aren't using them. Nevertheless, the fix is simple as always: simply
- replace 'renderer' with 'sigrenderer'. So the new functions are:
-
- AL_DUH_PLAYER *al_duh_encapsulate_sigrenderer(DUH_SIGRENDERER *sr,
- float volume, long bufsize, int freq);
- DUH_SIGRENDERER *al_duh_get_sigrenderer(AL_DUH_PLAYER *dp);
- DUH_SIGRENDERER *al_duh_decompose_to_sigrenderer(AL_DUH_PLAYER *dp);
-
-
-*********************
-*** Miscellaneous ***
-*********************
-
-
-long duh_render_signal(DUH_SIGRENDERER *sigrenderer,
- float volume, float delta,
- long size, sample_t **samples);
-
- This function used to return samples in DUMB's internal format. This
- format consisted of 32-bit integers whose 'normal range' was -0x8000 to
- 0x7FFF (any samples outside this range would have to be clipped when sent
- to the sound card).
-
- DUMB's internal format has changed. DUMB still uses 32-bit integers, but
- now the normal range is -0x800000 to 0x7FFFFF. The lowest eight bits are
- discarded at the final stage by duh_render() when you ask for 16-bit
- output. A new function, duh_sigrenderer_get_samples(), will return samples
- in DUMB's new internal format. It takes exactly the same parameters, so
- all you have to do to the call itself is change the name; however, you
- will most likely have to change your code to account for the new
- normalised range.
-
- duh_render_signal() will still be able to give you the samples in DUMB's
- old internal format, but it is inefficient. You should change your code as
- soon as possible.
-
-
-typedef void (*DUH_SIGRENDERER_CALLBACK)(void *data, sample_t **samples,
- int n_channels, long length);
-
-void duh_sigrenderer_set_callback(DUH_SIGRENDERER *sigrenderer,
- DUH_SIGRENDERER_CALLBACK callback, void *data);
-
- This callback was intended to allow you to analyse the output. It was by
- no means intended to let you modify the output. For this reason, the names
- have been changed to DUH_SIGRENDERER_ANALYSER_CALLBACK and
- duh_sigrenderer_set_analyser_callback, and the 'samples' parameter to your
- callback should now be specified as follows:
-
- const sample_t *const *samples
-
- The first 'const' indicates that you must not modify the samples. The
- second indicates that you must not modify the pointers to each channel.
-
- There is a second reason why this change was necessary, and it is the one
- described further up for duh_render_signal()'s entry: the format in which
- the samples themselves are stored has changed. They are 256 times as
- large, with a normal range from -0x800000 to 0x7FFFFF. You will most
- likely need to change your code to account for this.
-
- If you try to call the old function, it will print a message to stderr
- directing you to this file, and it will not install the callback. You
- shouldn't be able to get this far without a compiler warning (or, if you
- don't have GCC 3.1 or later, some compiler errors).
-
- If you wanted to use this callback to apply a DSP effect, don't worry;
- there is a better way of doing this. It is undocumented, so contact me
- and I shall try to help. Contact details are at the bottom of this file.
-
- For reference, here are the new definitions:
-
- typedef void (*DUH_SIGRENDERER_ANALYSER_CALLBACK)(void *data,
- const sample_t *const *samples, int n_channels, long length);
-
- void duh_sigrenderer_set_analyser_callback(DUH_SIGRENDERER *sigrenderer,
- DUH_SIGRENDERER_ANALYSER_CALLBACK callback, void *data);
-
-
-int dumb_resampling_quality;
-
- This variable has changed meaning. It used to hold a value from 0 to 4,
- whose meaning was as follows:
-
- 0 - aliasing
- 1,2 - linear interpolation
- 3 - quadratic interpolation
- 4 - cubic interpolation
-
- 0,1 - always use a straightforward interpolation algorithm
- 2,3,4 - when decimating (increasing the pitch), use a linear average
- algorithm designed to reduce frequencies that would otherwise
- reflect off the Nyquist
-
- Now the variable only holds values from 0 to 2, and these values have
- preprocessor constants associated with them. The somewhat inappropriate
- quadratic interpolation has been removed. The linear average algorithm has
- also been removed, and may or may not come back; there are probably more
- efficient ways of achieving the same effect, which I shall be
- investigating in the future.
-
- This change will have hardly any noticeable effect on existing programs.
- Levels 2, 3 and 4 used considerably more processor time because of the
- linear average algorithm. Likewise, Level 2 in the new scheme (cubic) uses
- considerably more processor time than Levels 1 and 0, and Levels 3 and 4
- will behave identically to Level 2.
-
-
-******************
-*** Conclusion ***
-******************
-
-
-"I conclude that... DUMB is the bestest music player in the world because...
-Complete this sentence in fifteen words or fewer... D'OH!"
-
-The preceding conclusion formerly appeared in dumb.txt, and is deprecated
-because it's lame.
-
-
-Ben Davis
-entheh@users.sf.net
-IRC EFnet #dumb
-See readme.txt for details on using IRC.
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