Moinsen..
ich hab' hier mal die Beschreibung eines Plugins für die Visualisierung in Winamp.. Das ist ein 1:1 Copy&Paste Zitat von
hier, allerdings ist die Seite früher oder später eh wieder down oder umgezogen (so ist das meistens) und dann ist auch der Code weg daher stell ich das nochmal hier für alle rein:
Data Structures
First off you have to create a
DLL. winamp expects your
DLL to export winampVisGetHeader
exports winampVisGetHeader;
Then in the
unit containing the rest of the code add the following data structures. Winamp will use this record to
pas information to and execute the functions it needs.
Delphi-Quellcode:
type
PWinampVisModule = ^TwinampVisModule;
TwinampVisModule =
record
description : PChar;
// description of module
hwndParent : HWND;
// parent window (filled in by calling app)
hDllInstance : HINST;
// instance handle to this DLL (filled in by calling app)
sRate : Cardinal;
// sample rate (filled in by calling app)
nCh : Cardinal;
// number of channels (filled in...)
latencyMs : Cardinal;
// latency from call to Render to actual drawing
delayMs : Cardinal;
// delay between calls to Render (in ms)
// the data is filled in according to the respective Nch entry
spectrumNCh : Cardinal;
// Number of channels
waveformNCh : Cardinal;
// Number of channels
spectrumData :
Array [0..1, 0..575]
of Byte;
// waveform data (values from 0-255)
waveformData :
Array [0..1, 0..575]
of Byte;
// spectrum data (values from 0-255)
// functions that winamp calls to configure the plugin, initialise ...
Config :
procedure(
const PVisModule : PwinampVisModule);
cdecl;
Init :
function (
const PVisModule : PwinampVisModule) : Integer;
cdecl;
Render :
function (
const PVisModule : PwinampVisModule) : Integer;
cdecl;
Quit :
procedure(
const PVisModule : PwinampVisModule);
cdecl;
userData :
procedure;
cdecl;
// user data, optional
end;
PwinampVisHeader = ^TwinampVisHeader;
TwinampVisHeader =
record
version : Integer;
description : PChar;
// description of library
getModule :
function (Which : Integer) : PwinampVisModule;
cdecl;
end;
I then also added a forward declaration of the functions that will be called by winamp.
Delphi-Quellcode:
// forward declaration of the procedures
function GetModule(Which :integer) :PWinAMPVisModule; cdecl;
procedure Config(const PVisModule : PWinAMPVisModule); cdecl;
function Init(const PVisModule : PWinAMPVisModule) : integer; cdecl;
function Render(const PVisModule : PWinAMPVisModule) :integer; cdecl;
procedure Quit(const PVisModule : PWinAMPVisModule); cdecl;
You also need to add the function that will be exported before you get to the implementation
function winampVisGetHeader : PwinampVisHeader; cdecl; export;
Global Variables
This section might change depending on your implementation of the plugin. For my plugin I created the window using
API calls. You could do it using the standard Delphi Forms.
Delphi-Quellcode:
implementation
const
WND_TITLE = '
Jan OpenGL WinAMP Plugin';
var
h_Wnd : HWND;
// Global window handle
h_DC : HDC;
// Global device context
h_RC : HGLRC;
// OpenGL rendering context
keys :
Array[0..255]
of Boolean;
// Holds keystrokes
Active : Boolean = FALSE;
// State of the plugin
Functions called by Winamp
This is a list of the functions called by winamp and what they are for.
WinAMPVisGetHeader : Return as pointer to the WinAMPVisHeader
Delphi-Quellcode:
function WinAMPVisGetHeader :PWinAMPVisHeader;
begin
Result := @HDR; // Return the main header
end;
GetModule : Returns a pointer to the WinampVisModule. A variable containing the plugin information and functions.
Delphi-Quellcode:
function GetModule(Which : integer) : PwinampVisModule;
begin
if which = 0 then
Result := @VisModule
else
Result := nil;
end;
Config : This function gets called when the user got to the plugin configuration section on winamp. It should display the plugin options like screensize and any other display options. These options should then be stored in the "plugin.ini" file in the winamp plugins folder.
Delphi-Quellcode:
procedure Config(const PVisModule : PWinAMPVisModule);
begin
Form1 :=TForm1.Create(nil);
try
Form1.ShowModal;
finally
Form1.Free;
end;
end;
Init : The initialisation function should get the plugin display options from the "plugin.ini" file in the winamp\plugins folder. All global variable get initialised here. In the code that I use, I create the glWindow here and initialise
OpenGL
Delphi-Quellcode:
function Init(const PVisModule :PWinAMPVisModule) :integer;
begin
...
// Get plugin config details
...
// create and initialise the window
...
end;
Render : This is the main function where everything happens. The number of times that this function gets called depends on the DelayMS value in the VisModule. A value of 25 will tell winamp to call this function every 25 milliseconds.
Here you would render the image and check for any key presses.
Delphi-Quellcode:
function Render(const PVisModule : PWinAMPVisModule) : Integer;
var LastTime : DWord;
begin
if Active then
begin
glDraw(PVisModule); // Draw the scene
SwapBuffers(h_DC); // Display the scene
if (keys[VK_ESCAPE]) then // If user pressed ESC then set finised TRUE
begin
Active :=FALSE;
PostQuitMessage(0);
Result :=1;
exit;
end
else
ProcessKeys(PVisModule); // Check for any other key Pressed
end;
Result :=0;
end;
Quit : Closes the window.
Delphi-Quellcode:
procedure Quit(const PVisModule : PWinAMPVisModule);
begin
glKillWnd(PVisModule, AppFullScreen);
end;
That's it. The other functions in my code are there to create the
OpenGL window, watch for key presses and to render the GL scene. They were copied from my
OpenGL template.