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GetShapeDmaBufferFull

Gets the buffer-full flag.

Syntax

Parameters

context   _In_
Type: SHAPE_DMA_CONTEXT*
Pointer to a SHAPE_DMA_CONTEXT structure.

Return value

Type: bool The buffer-full flag.

Remarks

The Direct Memory Access (DMA) system supports read and write functionality with automatic float-to-integer and integer-to-float conversion. The DMA system uses circular buffers containing de-interleaved samples in 128-sample blocks. The DMA processor allows the Scalable Hardware Audio Processing Engine (SHAPE) to send data from mix buffers to main system memory and retrieve data from main system into the mix buffers for further processing. DMA is done on a block basis, transferring one audio frame of data at a time. To facilitate block-interleaved data, a skip value specifies the number of audio frame blocks in system memory to skip (from the base address) when reading or writing samples. Multichannel streams therefore require one DMA context per channel. Audio data samples are always read and written as 32-bit values, either integer or float, as specified in the floatConvert flag of the SHAPE_DMA_CONTEXT structure. Note that the direction of the DMA (read or write) is specified in the DMA command, not in the DMA context. This helps reduce the amount of data bandwidth. The DMA engine has no signal processing, but can perform float-to-integer conversion (or integer-to-float). This allows the application CPU to process data samples in floating-point format. To calculate the size of a DMA buffer, use the following formula:
The read and write pointers are incremented as follows:
Addresses within the audio buffer are calculated as follows:

Requirements

Header: shapedmacontext.h Supported platforms: XBOX One family consoles and XBOX Series consoles

See also

Overview of SHAPE
ShapeDmaContext
Last modified on August 20, 2026