text: // This was created from released VST2.x plugins, and is technically under the 2-clause BSD license.
  // Depending on which country you are in, Steinberg can do fuck all about this. Notable countries for
  // this are most members of the United States of America, the entirety of Europe, Japan, and Russia.
  // Consult a lawyer if you don't know if clean room reverse engineering is allowed in your country.
  
  // See README.md for all information.
  
  // Known additional information:
  // - Function call standard seems to be stdcall.
  // - Everything is aligned to 8 bytes.
  
  // VST Versioning:
  // - Base-10, thus can't store many version numbers.
  // - Always four components, with the major one being able to store the most numbers.
  // - Format is A...ABCD, so 1.2.3.4 would turn into 1234.
  
  #pragma once
  #ifndef VST2SDK_VST_H
  #define VST2SDK_VST_H
  
  #define VST_FUNCTION_INTERFACE __stdcall
  #define VST_ALIGNMENT 8
  #define VST_MAGICNUMBER 'VstP'
  
  #define VST_VENDOR_BUFFER_SIZE 64  // Vendor
  #define VST_PRODUCT_BUFFER_SIZE 64 // Product
  #define VST_EFFECT_BUFFER_SIZE 32  // Effect
  #define VST_NAME_BUFFER_SIZE 64    // Names
  
  #define VST_MAX_CHANNELS 32 // Couldn't find any audio editing software which would attempt to add more channels.
  
  #pragma pack(push, VST_ALIGNMENT)
  
  #ifdef __cplusplus
  #include <cinttypes>
  extern "C" {
  #else
  #include <inttypes.h>
  #endif
  
  /*******************************************************************************
  |* Enumeration
  |*/
  enum VST_VERSION {
  	VST_VERSION_1       = 0,    // Anything before 2.0, used by official plug-ins.
  	VST_VERSION_1_0_0_0 = 1000, // 1.0, used by some third-party plug-ins.
  	VST_VERSION_1_1_0_0 = 1100, // 1.1, used by some third-party plug-ins.
  	VST_VERSION_2       = 2,    // 2.0, used by official plug-ins.
  	VST_VERSION_2_0_0_0 = 2000, // 2.0, used by some third-party plug-ins.
  	VST_VERSION_2_1_0_0 = 2100, // 2.1
  	VST_VERSION_2_2_0_0 = 2200, // 2.2
  	VST_VERSION_2_3_0_0 = 2300, // 2.3
  	VST_VERSION_2_4_0_0 = 2400, // 2.4
  
  	// Pad to force 32-bit number.
  	_VST_VERSION_PAD = 0xFFFFFFFFul,
  };
  
  enum VST_CATEGORY {
  	VST_CATEGORY_UNCATEGORIZED = 0x00,
  	VST_CATEGORY_01            = 0x01,
  	VST_CATEGORY_02            = 0x02,
  	VST_CATEGORY_03            = 0x03,
  	VST_CATEGORY_04            = 0x04,
  	VST_CATEGORY_05            = 0x05,
  	VST_CATEGORY_06            = 0x06,
  	VST_CATEGORY_07            = 0x07,
  	VST_CATEGORY_RESTORATION   = 0x08, // Denoising and similar effects.
  	VST_CATEGORY_09            = 0x09,
  	VST_CATEGORY_CONTAINER     = 0x0A, // Plugin contains more than one Plugin.
  	VST_CATEGORY_0B            = 0x0B,
  	VST_CATEGORY_MAX, // Not part of specification, marks maximum category.
  
  	// Pad to force 32-bit number.
  	_VST_CATEGORY_PAD = 0xFFFFFFFFul,
  };
  
  enum VST_EFFECT_OPCODE {
  	/* Create/Initialize the effect (if it has not been created already).
  	 * 
  	 * @return Always 0.
  	 */
  	VST_EFFECT_OPCODE_00         = 0x00,
  	VST_EFFECT_OPCODE_CREATE     = 0x00,
  	VST_EFFECT_OPCODE_INITIALIZE = 0x00,
  
  	/* Destroy the effect (if there is any) and free its memory.
  	 *
  	 * This should destroy the actual object created by VST_ENTRYPOINT.
  	 * 
  	 * @return Always 0.
  	 */
  	VST_EFFECT_OPCODE_01      = 0x01,
  	VST_EFFECT_OPCODE_DESTROY = 0x01,
  
  	/* Set Program
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_02 = 0x02,
  
  	/* Get Program
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_03 = 0x03,
  
  	/* Set Program Name
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_04 = 0x04,
  
  	/* Get Program Name
  	 *
  	 * "Returns 0. If ptr is valid, sets the first byte of ptr to 0 then returns 0."
  	 */
  	VST_EFFECT_OPCODE_05 = 0x05,
  
  	/* Get the value? label for the parameter.
  	 * 
  	 * @param p_int1 Parameter index.
  	 * @param p_ptr 'char[8]'
  	 * @return 0 on success, 1 on failure.
  	 */
  	VST_EFFECT_OPCODE_06             = 0x06,
  	VST_EFFECT_OPCODE_PARAM_GETLABEL = 0x06,
  
  	/* Get the string value for the parameter.
  	 * 
  	 * @param p_int1 Parameter index.
  	 * @param p_ptr 'char[8]'
  	 * @return 0 on success, 1 on failure.
  	 */
  	VST_EFFECT_OPCODE_07             = 0x07,
  	VST_EFFECT_OPCODE_PARAM_GETVALUE = 0x07,
  
  	/* Get the name for the parameter.
  	 * 
  	 * @param p_int1 Parameter index.
  	 * @param p_ptr 'char[8]'
  	 * @return 0 on success, 1 on failure.
  	 */
  	VST_EFFECT_OPCODE_08            = 0x08,
  	VST_EFFECT_OPCODE_PARAM_GETNAME = 0x08,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_09 = 0x09,
  
  	/* Set the new sample rate for the plugin to use.
  	 * 
  	 * @param p_float New sample rate as a float (double on 64-bit because register upgrades).
  	 */
  	VST_EFFECT_OPCODE_0A              = 0x0A,
  	VST_EFFECT_OPCODE_SETSAMPLERATE   = 0x0A,
  	VST_EFFECT_OPCODE_SET_SAMPLE_RATE = 0x0A,
  
  	/* Sets the block size, which is the maximum number of samples passed into the effect via process calls.
  	 *
  	 * @param p_int2 The maximum number of samples to be passed in.
  	 */
  	VST_EFFECT_OPCODE_0B             = 0x0B,
  	VST_EFFECT_OPCODE_SETBLOCKSIZE   = 0x0B,
  	VST_EFFECT_OPCODE_SET_BLOCK_SIZE = 0x0B,
  
  	/* Effect processing should be suspended/paused.
  	 *
  	 * Unclear if this is should result in a flush of buffers.
  	 * 
  	 * @param p_int2 0 if the effect should suspend processing, 1 if it should resume.
  	 */
  	VST_EFFECT_OPCODE_0C      = 0x0C,
  	VST_EFFECT_OPCODE_SUSPEND = 0x0C,
  
  	/* Retrieve the client rect size of the plugins window.
  	 * If no window has been created, returns the default rect.
  	 *
  	 * @param p_ptr Pointer of type 'struct vst_rect*'.
  	 * @return On success, returns 1 and updates p_ptr to the rect. On failure, returns 0.
  	 */
  	VST_EFFECT_OPCODE_0D             = 0x0D,
  	VST_EFFECT_OPCODE_WINDOW_GETRECT = 0x0D,
  
  	/* Create the window for the plugin.
  	 * 
  	 * @param p_ptr HWND of the parent window.
  	 * @return 0 on failure, or HWND on success.
  	 */
  	VST_EFFECT_OPCODE_0E            = 0x0E,
  	VST_EFFECT_OPCODE_WINDOW_CREATE = 0x0E,
  
  	/* Destroy the plugins window.
  	 * 
  	 * @return Always 0.
  	 */
  	VST_EFFECT_OPCODE_0F             = 0x0F,
  	VST_EFFECT_OPCODE_WINDOW_DESTROY = 0x0F,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_10 = 0x10,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_11 = 0x11,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_12 = 0x12,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_13 = 0x13,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_14 = 0x14,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_15 = 0x15,
  
  	/* Always returns the FourCC 'NvEF' (0x4E764566).
  	 */
  	VST_EFFECT_OPCODE_16 = 0x16,
  
  	/* Get Chunk
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_17 = 0x17,
  
  	/* Set Chunk
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_18 = 0x18,
  
  	// VST2.x starts here.
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_19 = 0x19,
  
  	/* Can the parameter be automated?
  	 *
  	 * @param p_int1 Index of the parameter.
  	 * @return 1 if the parameter can be automated, otherwise 0.
  	 */
  	VST_EFFECT_OPCODE_1A                  = 0x1A,
  	VST_EFFECT_OPCODE_PARAM_ISAUTOMATABLE = 0x1A,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_1B = 0x1B,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_1C = 0x1C,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_1D = 0x1D, // See VST_EFFECT_OPCODE_05
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_1E = 0x1E,
  
  	/* Input connected.
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_1F = 0x1F,
  
  	/* Input disconnected.
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_20 = 0x20,
  
  	/* Retrieve the name of the input channel at the given index.
  	 *
  	 * @param p_int1 Index of the input to get the name for.
  	 * @param p_ptr Pointer to a char* buffer able to hold at minimum 20 characters. Might need to be 32 even.
  	 * @return 0 on failure, 1 on success.
  	 */
  	VST_EFFECT_OPCODE_21                   = 0x21,
  	VST_EFFECT_OPCODE_INPUT_GETCHANNELNAME = 0x21,
  	VST_EFFECT_OPCODE_INPUT_CHANNEL_NAME   = 0x21,
  
  	/* Retrieve the name of the output channel at the given index.
  	 *
  	 * @param p_int1 Index of the output to get the name for.
  	 * @param p_ptr Pointer to a char* buffer able to hold at minimum 20 characters. Might need to be 32 even.
  	 * @return 0 on failure, 1 on success.
  	 */
  	VST_EFFECT_OPCODE_22                    = 0x22,
  	VST_EFFECT_OPCODE_OUTPUT_GETCHANNELNAME = 0x22,
  	VST_EFFECT_OPCODE_OUTPUT_CHANNEL_NAME   = 0x22,
  
  	/* Retrieve category of this effect.
  	 *
  	 * @return The category that this effect is in, see VST_CATEGORY.
  	 */
  	VST_EFFECT_OPCODE_23              = 0x23,
  	VST_EFFECT_OPCODE_EFFECT_CATEGORY = 0x23,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_24 = 0x24,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_25 = 0x25,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_26 = 0x26,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_27 = 0x27,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_28 = 0x28,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_29 = 0x29,
  
  	/* Set the speaker arrangement 
  	 *
  	 * @param p_int2 (vst_speaker_arrangement*) Pointer to a pointer to the speaker arrangement for the input.
  	 * @param p_ptr (vst_speaker_arrangement*) Pointer to a pointer to the speaker arrangement for the output.
  	 */
  	VST_EFFECT_OPCODE_2A                      = 0x2A,
  	VST_EFFECT_OPCODE_SET_SPEAKER_ARRANGEMENT = 0x2A,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_2B = 0x2B,
  
  	/* Enable/Disable bypassing the effect.
  	 *
  	 * @param p_int2 Zero if bypassing the effect is disabled, otherwise 1.
  	 */
  	VST_EFFECT_OPCODE_2C     = 0x2C,
  	VST_EFFECT_OPCODE_BYPASS = 0x2C,
  
  	/* Retrieve the effect name into the ptr buffer.
  	 *
  	 * @param p_ptr char[64] Buffer containing a zero-terminated effect information string. May be shorter than 64 bytes on older hosts.
  	 * @return Always 0, even on failure.
  	 */
  	VST_EFFECT_OPCODE_2D          = 0x2D,
  	VST_EFFECT_OPCODE_GETNAME     = 0x2D,
  	VST_EFFECT_OPCODE_EFFECT_NAME = 0x2D,
  
  	/* Translate an error code to a string.
  	 *
  	 * @param p_ptr char[256] Buffer that should contain a zero-terminated error string.
  	 */
  	VST_EFFECT_OPCODE_2E              = 0x2E,
  	VST_EFFECT_OPCODE_TRANSLATE_ERROR = 0x2E,
  
  	/* Retrieve the vendor name into the ptr buffer.
  	 *
  	 * @param p_ptr char[64] Buffer containing a zero-terminated vendor information string. May be shorter than 64 bytes on older hosts.
  	 * @return Always 0, even on failure.
  	 */
  	VST_EFFECT_OPCODE_2F          = 0x2F,
  	VST_EFFECT_OPCODE_GETVENDOR   = 0x2F,
  	VST_EFFECT_OPCODE_VENDOR_NAME = 0x2F,
  
  	/* See VST_EFFECT_OPCODE_GETNAME
  	 *
  	 * Rarely used, if at all even supported. Not sure what the purpose of this is even.
  	 */
  	VST_EFFECT_OPCODE_30           = 0x30,
  	VST_EFFECT_OPCODE_GETNAME2     = 0x30,
  	VST_EFFECT_OPCODE_PRODUCT_NAME = 0x30,
  
  	/* Retrieve the vendor version in return value.
  	 *
  	 * @return Version.
  	 */
  	VST_EFFECT_OPCODE_31               = 0x31,
  	VST_EFFECT_OPCODE_GETVENDORVERSION = 0x31,
  	VST_EFFECT_OPCODE_VENDOR_VERSION   = 0x31,
  
  	/* User defined OP Code, for custom interaction.
  	 * 
  	 */
  	VST_EFFECT_OPCODE_32     = 0x32,
  	VST_EFFECT_OPCODE_CUSTOM = 0x32,
  
  	/* Test for support of a specific named feature.
  	 * 
  	 * @param p_ptr Pointer to a zero-terminated buffer containing the feature name.
  	 * @return Non-zero if the feature is supported, otherwise 0.
  	 */
  	VST_EFFECT_OPCODE_33       = 0x33,
  	VST_EFFECT_OPCODE_SUPPORTS = 0x33,
  
  	/* Number of samples that are at the tail at the end of playback.
  	 * 
  	 * @return 0 or 1 for no tail, > 1 for number of samples to tail.
  	 */
  	VST_EFFECT_OPCODE_34             = 0x34,
  	VST_EFFECT_OPCODE_GETTAILSAMPLES = 0x34,
  	VST_EFFECT_OPCODE_TAIL_SAMPLES   = 0x34,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_35 = 0x35,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_36 = 0x36,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_37 = 0x37,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_38 = 0x38,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_39 = 0x39,
  
  	/* Retrieve the VST Version supported.
  	 *
  	 * @return Return 0 for <2.0, 2 for 2.0, 2100 for 2.1, 2200 for 2.2, 2300 for 2.3, etc.
  	 */
  	VST_EFFECT_OPCODE_3A          = 0x3A,
  	VST_EFFECT_OPCODE_VST_VERSION = 0x3A,
  
  	// VST 2.1 or later
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_3B = 0x3B,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_3C = 0x3C,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_3D = 0x3D,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_3E = 0x3E,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_3F = 0x3F,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_40 = 0x40,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_41 = 0x41,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_42 = 0x42,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_43 = 0x43,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_44 = 0x44,
  
  	// VST 2.3 or later
  
  	/* Retrieve the speaker arrangement.
  	 *
  	 * @param p_int2 (vst_speaker_arrangement**) Pointer to a pointer to the speaker arrangement for the input.
  	 * @param p_ptr (vst_speaker_arrangement**) Pointer to a pointer to the speaker arrangement for the output.
  	 */
  	VST_EFFECT_OPCODE_45                      = 0x45,
  	VST_EFFECT_OPCODE_GET_SPEAKER_ARRANGEMENT = 0x45,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_46 = 0x46,
  
  	/* Begin processing of audio.
  	 *
  	 * 
  	 * 
  	 */
  	VST_EFFECT_OPCODE_PROCESS_BEGIN = 0x47,
  
  	/* End processing of audio.
  	 *
  	 * 
  	 *
  	 */
  	VST_EFFECT_OPCODE_PROCESS_END = 0x48,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_49 = 0x49,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_4A = 0x4A,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_4B = 0x4B,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_4C = 0x4C,
  
  	// VST 2.4 or later
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_4D = 0x4D,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_4E = 0x4E,
  
  	/*
  	 *
  	 *
  	 */
  	VST_EFFECT_OPCODE_4F = 0x4F,
  
  	// Highest number of known OPCODE.
  	VST_EFFECT_OPCODE_MAX,
  
  	// Pad to force 32-bit number.
  	_VST_EFFECT_OPCODE_PAD = 0xFFFFFFFFul,
  };
  
  enum VST_HOST_OPCODE {
  	/*
  	 * @param int1 -1 or Parameter Index
  	 * @return Expected to return... something.
  	 */
  	VST_HOST_OPCODE_00 = 0x00, // cb(vst, 0x00, ?, 0, 0);
  	VST_HOST_OPCODE_01 = 0x01,
  	VST_HOST_OPCODE_02 = 0x02, // bool cb(0, 0x02, 0, 0, 0);
  	VST_HOST_OPCODE_03 = 0x03,
  	VST_HOST_OPCODE_04 = 0x04,
  	VST_HOST_OPCODE_05 = 0x05,
  	VST_HOST_OPCODE_06 = 0x06,
  	VST_HOST_OPCODE_07 = 0x07,
  	VST_HOST_OPCODE_08 = 0x08,
  	VST_HOST_OPCODE_09 = 0x09,
  	VST_HOST_OPCODE_0A = 0x0A,
  	VST_HOST_OPCODE_0B = 0x0B,
  	VST_HOST_OPCODE_0C = 0x0C,
  	VST_HOST_OPCODE_0D = 0x0D,
  	VST_HOST_OPCODE_0E = 0x0E,
  	VST_HOST_OPCODE_0F = 0x0F,
  	VST_HOST_OPCODE_10 = 0x10,
  	VST_HOST_OPCODE_11 = 0x11,
  	VST_HOST_OPCODE_12 = 0x12,
  	VST_HOST_OPCODE_13 = 0x13,
  	VST_HOST_OPCODE_14 = 0x14,
  	VST_HOST_OPCODE_15 = 0x15,
  	VST_HOST_OPCODE_16 = 0x16,
  	VST_HOST_OPCODE_17 = 0x17,
  	VST_HOST_OPCODE_18 = 0x18,
  	VST_HOST_OPCODE_19 = 0x19,
  	VST_HOST_OPCODE_1A = 0x1A,
  	VST_HOST_OPCODE_1B = 0x1B,
  	VST_HOST_OPCODE_1C = 0x1C,
  	VST_HOST_OPCODE_1D = 0x1D,
  	VST_HOST_OPCODE_1E = 0x1E,
  	VST_HOST_OPCODE_1F = 0x1F,
  	VST_HOST_OPCODE_20 = 0x20,
  	VST_HOST_OPCODE_21 = 0x21,
  	VST_HOST_OPCODE_22 = 0x22,
  	VST_HOST_OPCODE_23 = 0x23,
  	VST_HOST_OPCODE_24 = 0x24,
  	VST_HOST_OPCODE_25 = 0x25,
  	VST_HOST_OPCODE_26 = 0x26,
  	VST_HOST_OPCODE_27 = 0x27,
  	VST_HOST_OPCODE_28 = 0x28,
  	VST_HOST_OPCODE_29 = 0x29,
  	VST_HOST_OPCODE_2A = 0x2A,
  
  	/* Parameter gained focus.
  	 *
  	 * @param int1 Parameter index.
  	 */
  	VST_HOST_OPCODE_2B = 0x2B,
  
  	/* Parameter lost focus.
  	 * 
  	 * @param int1 Parameter index.
  	 */
  	VST_HOST_OPCODE_2C = 0x2C,
  
  	VST_HOST_OPCODE_2D = 0x2D,
  	VST_HOST_OPCODE_2E = 0x2E,
  	VST_HOST_OPCODE_2F = 0x2F,
  
  	// Highest number of known OPCODE.
  	VST_HOST_OPCODE_MAX,
  
  	// Pad to force 32-bit number.
  	_VST_HOST_OPCODE_PAD = 0xFFFFFFFFul,
  };
  
  enum VST_ARRANGEMENT_TYPE {
  	/* Custom speaker arrangement.
  	 *
  	 * Accidentally discovered through random testing.
  	 */
  	VST_ARRANGEMENT_TYPE_CUSTOM = -2,
  
  	/* Unknown/Empty speaker layout.
  	 *
  	 */
  	VST_ARRANGEMENT_TYPE_UNKNOWN = -1,
  
  	/* Mono
  	 */
  	VST_ARRANGEMENT_TYPE_MONO = 0,
  
  	/* Stereo
  	 */
  	VST_ARRANGEMENT_TYPE_STEREO = 1,
  
  	/* 5.1
  	 */
  	VST_ARRANGEMENT_TYPE_5_1 = 0x0F,
  
  	// Pad to force 32-bit number.
  	_VST_ARRANGEMENT_TYPE_PAD = 0xFFFFFFFFul,
  };
  
  enum VST_SPEAKER_TYPE {
  	VST_SPEAKER_TYPE_MONO       = 0,
  	VST_SPEAKER_TYPE_LEFT       = 1,
  	VST_SPEAKER_TYPE_RIGHT      = 2,
  	VST_SPEAKER_TYPE_CENTER     = 3,
  	VST_SPEAKER_TYPE_LFE        = 4,
  	VST_SPEAKER_TYPE_LEFT_SIDE  = 5,
  	VST_SPEAKER_TYPE_RIGHT_SIDE = 6,
  
  	// Pad to force 32-bit number.
  	_VST_SPEAKER_TYPE_PAD = 0xFFFFFFFFul,
  };
  
  /*******************************************************************************
  |* Structures
  |*/
  
  struct vst_rect {
  	int16_t left;
  	int16_t top;
  	int16_t right;
  	int16_t bottom;
  };
  
  struct vst_effect {
  	int32_t magic_number; // Should always be VST_MAGICNUMBER
  
  	// 64-bit adds 4-byte padding here to align pointers.
  
  	/* Control the VST through an opcode and up to four parameters.
  	 * 
  	 * @param this Pointer to the effect itself.
  	 * @param opcode The opcode to run, see VST_EFFECT_OPCODES.
  	 * @param p_int1 Parameter, see VST_EFFECT_OPCODES.
  	 * @param p_int2 Parameter, see VST_EFFECT_OPCODES.
  	 * @param p_ptr Parameter, see VST_EFFECT_OPCODES.
  	 * @param p_float Parameter, see VST_EFFECT_OPCODES.
  	 */
  	intptr_t(VST_FUNCTION_INTERFACE* control)(vst_effect* pthis, VST_EFFECT_OPCODE opcode, int32_t p_int1,
  											  intptr_t p_int2, void* p_ptr, float p_float);
  
  	/* Process the given number of samples in inputs and outputs.
  	 *
  	 * Different to process_float how? Never seen any difference.
  	 * 
  	 * @param pthis Pointer to the effect itself.
  	 * @param inputs Pointer to an array of 'const float[samples]' with size numInputs.
  	 * @param outputs Pointer to an array of 'float[samples]' with size numOutputs.
  	 * @param samples Number of samples per channel in inputs.
  	 */
  	void(VST_FUNCTION_INTERFACE* process)(vst_effect* pthis, const float* const* inputs, float** outputs,
  										  int32_t samples);
  
  	/* Updates the value for the parameter at the given index, or does nothing if out of bounds.
  	 * 
  	 * @param pthis Pointer to the effect itself.
  	 * @param index Parameter index.
  	 * @param value New value for the parameter.
  	 */
  	void(VST_FUNCTION_INTERFACE* set_parameter)(vst_effect* pthis, uint32_t index, float value);
  
  	/* Returns the value stored for the parameter at index, or 0 if out of bounds.
  	 * 
  	 * @param pthis Pointer to the effect itself.
  	 * @param index Parameter index.
  	 * @return float Value of the parameter.
  	 */
  	float(VST_FUNCTION_INTERFACE* get_parameter)(vst_effect* pthis, uint32_t index);
  
  	int32_t num_programs; // Number of possible programs.
  	int32_t num_params;   // Number of possible parameters.
  	int32_t num_inputs;   // Number of inputs.
  	int32_t num_outputs;  // Number of outputs.
  
  	/* Bitflags
  	 * 
  	 * Bit		Description
  	 * 1		Effect has "Editor"
  	 * 2		Unknown (Found in: ReaDelay)
  	 * 3		Unknown (Found in: ReaDelay)
  	 * 4		Unknown (Found in: ReaDelay)
  	 * 5		Has process_float (Found in: ReaDelay, ReaComp, ReaControlMIDI, ReaStream, ReaFir)
  	 * 6		Unknown (Found in: ReaControlMIDI, ReaStream, ReaFir)
  	 * 10		Unknown (Found in: ReaFir)
  	 * 13		Has process_double (Found in: ReaControlMIDI)
  	 */
  	int32_t flags;
  
  	// 64-bit adds 4-byte padding here to align pointers.
  
  	void* _unknown_ptr_00[2];
  
  	/* Initial delay before processing of samples can actually begin in Samples.
  	 *
  	 * Should be updated before or during handling the 0x47 control call. 
  	 */
  	int32_t delay;
  
  	int32_t _unknown_int32_00[2]; // Unknown int32_t values.
  	float   _unknown_float_00;    // Seems to always be 1.0
  
  	void* effect_internal; // Pointer to Plugin internal data
  	void* host_internal;   // Pointer to Host internal data.
  
  	/* Id of the plugin.
  	 *
  	 * Due to this not being enough for uniqueness, it should not be used alone 
  	 * for indexing. Ideally you want to index like this:
  	 *     [unique_id][module_name][version][flags]
  	 * If any of the checks after unique_id fail, you default to the first 
  	 * possible choice.
  	 */
  	int32_t unique_id;
  
  	/* Plugin version
  	 * 
  	 * Unrelated to the minimum VST Version, but often the same.
  	 */
  	int32_t version;
  
  	// There is no padding here if everything went right.
  
  	/* Process the given number of single samples in inputs and outputs.
  	 *
  	 * @param pthis Pointer to the effect itself.
  	 * @param inputs Pointer to an array of 'const float[samples]' with size numInputs.
  	 * @param outputs Pointer to an array of 'float[samples]' with size numOutputs.
  	 * @param samples Number of samples per channel in inputs.
  	 */
  	void(VST_FUNCTION_INTERFACE* process_float)(vst_effect* pthis, const float* const* inputs, float** outputs,
  												int32_t samples);
  
  	/* Process the given number of double samples in inputs and outputs.
  	 *
  	 * Used only by 2.4 hosts and plugins, possibly restricted to said version.
  	 * 
  	 * @param pthis Pointer to the effect itself.
  	 * @param inputs Pointer to an array of 'const double[samples]' with size numInputs.
  	 * @param outputs Pointer to an array of 'double[samples]' with size numOutputs.
  	 * @param samples Number of samples per channel in inputs.
  	 */
  	void(VST_FUNCTION_INTERFACE* process_double)(vst_effect* pthis, const double* const* inputs, double** outputs,
  												 int32_t samples);
  
  	// Everything after this is unknown and was present in reacomp-standalone.dll.
  	uint8_t _unknown[56]; // 56-bytes of something. Could also just be 52-bytes.
  };
  
  struct vst_speaker_properties {
  	float            _unknown_00; // 10.0 if LFE, otherwise random? Never exceeds -PI to PI range.
  	float            _unknown_04; // 10.0 if LFE, otherwise random? Never exceeds -PI to PI range.
  	float            _unknown_08; // 0.0 if LFE, otherwise 1.0.
  	float            _unknown_0C;
  	char             name[VST_NAME_BUFFER_SIZE];
  	VST_SPEAKER_TYPE type;
  
  	uint8_t _unknown[28]; // Padding detected from testing.
  };
  
  struct vst_speaker_arrangement {
  	VST_ARRANGEMENT_TYPE   type;                       // See VST_SPEAKER_ARRANGEMENT_TYPE
  	int32_t                channels;                   // Number of channels in speakers.
  	vst_speaker_properties speakers[VST_MAX_CHANNELS]; // Array of speaker properties, actual size defined by channels.
  };
  
  /* Callback used by the plugin to interface with the host.
   * 
   * @param opcode See VST_HOST_OPCODE
   * @param p_str Zero terminated string or null on call.
   * @return ?
   */
  typedef intptr_t (*vst_host_callback)(vst_effect* plugin, VST_HOST_OPCODE opcode, int32_t p_int1, int64_t p_int2,
  									  const char* p_str, int32_t p_int3);
  
  static const char* vst_host_string[] = {
  	"GetResourcePath", // ReaControlMIDI
  	"get_ini_file",    // ReaControlMIDI
  	"resolve_fn",      // ReaControlMIDI
  };
  
  /* Entry point for VST2.x plugins.
   *
   * @return A new instance of the VST2.x effect.
   */
  #define VST_ENTRYPOINT vst_effect* VSTPluginMain(vst_host_callback callback)
  #define VST_ENTRYPOINT_WINDOWS                   \
  	vst_effect* MAIN(vst_host_callback callback) \
  	{                                            \
  		return VSTPluginMain(callback);          \
  	}
  #define VST_ENTRYPOINT_MACOS                           \
  	vst_effect* main_macho(vst_host_callback callback) \
  	{                                                  \
  		return VSTPluginMain(callback);                \
  	}
  
  #ifdef __cplusplus
  }
  #endif
  
  // Variable size variant of vst_speaker_arrangement.
  #ifdef __cplusplus
  template<size_t T>
  struct vst_speaker_arrangement_t {
  	VST_ARRANGEMENT_TYPE   type;        // See VST_SPEAKER_ARRANGEMENT_TYPE
  	int32_t                channels;    // Number of channels in speakers.
  	vst_speaker_properties speakers[T]; // Array of speaker properties, actual size defined by channels.
  };
  #endif
  
  #pragma pack(pop)
  
  #endif
  