VIS.H

// This file is part of: Geiss screensaver and Winamp music visualization plug-in
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// 3-Clause BSD License
//
// Copyright (c) 1998-2022 Ryan Geiss (@geissomatik)
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice, this
//    list of conditions and the following disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright notice,
//    this list of conditions and the following disclaimer in the documentation
//    and/or other materials provided with the distribution.
//
// 3. Neither the name of the copyright holder nor the names of its
//    contributors may be used to endorse or promote products derived from
//    this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
// OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

// notes:
// any window that remains in foreground should optimally pass 
// keystrokes to the parent (winamp's) window, so that the user
// can still control it. unless escape is hit, or some option 
// key specific to the vis is hit. As for storing configuration,
// Configuration data should be stored in <dll directory>\plugin.ini
// Look at the example plugin for a framework.

// ints are 32 bits, and structure members are aligned on the default 8 byte boundaries
// tested with VC++ 4.2 and 5.0


typedef struct winampVisModule {
  char *description; // description of module
  HWND hwndParent;   // parent window (filled in by calling app)
  HINSTANCE hDllInstance; // instance handle to this DLL (filled in by calling app)
  int sRate;		 // sample rate (filled in by calling app)
  int nCh;			 // number of channels (filled in...)
  int latencyMs;     // latency from call of RenderFrame to actual drawing
                     // (calling app looks at this value when getting data)
  int delayMs;       // delay between calls in ms

  // the data is filled in according to the respective Nch entry
  int spectrumNch;
  int waveformNch;
  unsigned char spectrumData[2][576];
  unsigned char waveformData[2][576];

  void (*Config)(struct winampVisModule *this_mod);  // configuration dialog
  int (*Init)(struct winampVisModule *this_mod);     // 0 on success, creates window, etc
  int (*Render)(struct winampVisModule *this_mod);   // returns 0 if successful, 1 if vis should end
  void (*Quit)(struct winampVisModule *this_mod);    // call when done

  void *userData; // user data, optional
} winampVisModule;

typedef struct {
  int version;       // VID_HDRVER
  char *description; // description of library
  winampVisModule* (*getModule)(int);
} winampVisHeader;

// exported symbols
typedef winampVisHeader* (*winampVisGetHeaderType)();

// version of current module (0x101 == 1.01)
#define VIS_HDRVER 0x101