DirectX SDK

DMUS_PORTCAPS

The DMUS_PORTCAPS structure receives information about a port enumerated by a call to the IDirectMusic::EnumPort method. The structure is also used to return information through the IDirectMusicPort::GetCaps method.

typedef struct _DMUS_PORTCAPS {
    DWORD dwSize;
    DWORD dwFlags;
    GUID  guidPort;
    DWORD dwClass;
    DWORD dwType;
    DWORD dwMemorySize;
    DWORD dwMaxChannelGroups;
    DWORD dwMaxVoices;
    DWORD dwMaxAudioChannels;
    DWORD dwEffectFlags;
    WCHAR wszDescription[DMUS_MAX_DESCRIPTION];
} DMUS_PORTCAPS, *LPDMUS_PORTCAPS;

Members

dwSize
Size of the structure, in bytes. This member must be initialized to sizeof(DMUS_PORTCAPS) before the structure is passed to any method.
dwFlags
Flags describing various capabilities of the port. This field can contain one or more of the following values:
DMUS_PC_DIRECTSOUND
The port supports streaming wave data to DirectSound.
DMUS_PC_DLS
The port supports DLS Level 1 sample collections.
DMUS_PC_DLS2
The port supports DLS Level 2 sample collections.
DMUS_PC_EXTERNAL
The port connects to devices outside the host—for example, devices connected over an external MIDI port such as the MPU-401.
DMUS_PC_GMINHARDWARE
The synthesizer has its own GM instrument set, so GM instruments do not need to be downloaded.
DMUS_PC_GSINHARDWARE
This port contains the Roland GS sound set in hardware.
DMUS_PC_MEMORYSIZEFIXED
Memory available for DLS instruments cannot be adjusted.
DMUS_PC_SHAREABLE
More than one port can be created that uses the same range of channel groups on the device. Unless this bit is set, the port can be opened only in exclusive mode. In exclusive mode, an attempt to create a port fails unless free channel groups are available to assign to the create request.
DMUS_PC_SOFTWARESYNTH
The port is a software synthesizer.
DMUS_PC_XGINHARDWARE
The port contains the Yamaha XG extensions in hardware.
guidPort
Identifier of the port. This value can be passed to the IDirectMusic::CreatePort method to get an IDirectMusicPort interface for the port.
dwClass
Class of this port. The following classes are defined:
DMUS_PC_INPUTCLASS
Input port.
DMUS_PC_OUTPUTCLASS
Output port.
dwType
Type of this port. The following types are defined:
DMUS_PORT_WINMM_DRIVER
Windows multimedia driver.
DMUS_PORT_USER_MODE_SYNTH
User-mode synthesizer.
DMUS_PORT_KERNEL_MODE
WDM driver.
dwMemorySize
Amount of memory available to store DLS instruments. If the port is using system memory and the amount is therefore limited only by the available system memory, this field contains DMUS_PC_SYSTEMMEMORY.
dwMaxChannelGroups
Maximum number of channel groups supported by this port. A channel group is a set of 16 MIDI channels.
dwMaxVoices
Maximum number of voices that can be allocated when this port is opened. The value can be –1 if the driver does not support returning this parameter.
dwMaxAudioChannels
Maximum number of audio channels that can be rendered by the port. The value can be –1 if the driver does not support returning this parameter.
dwEffectFlags
Flags indicating what audio effects are available on the port.

The following flags are defined:

DMUS_EFFECT_NONE
No effects are supported.
DMUS_EFFECT_REVERB
The port supports reverb.
DMUS_EFFECT_CHORUS
The port supports chorus.
wszDescription
Description of the port. This can be a system-generated name, such as L"MPU-401 Output Port [330]", or a user-specified friendly name, such as L"Port w/ External SC-55".

Requirements

  Windows NT/2000: Requires Windows 2000.
  Windows 95/98: Requires Windows 95 or later. Available as a redistributable for Windows 95.
  Header: Declared in dmusicc.h.