QMemoryBarrier

Class to emplace a memory barrier. More…

Synopsis

Functions

• def waitOperations ()

Slots

• def setWaitOperations (operations)

Signals

• def waitOperationsChanged (barrierTypes)

Detailed Description

A QMemoryBarrier FrameGraph node is used to emplace a specific memory barrier at a specific time of the rendering. This is required to properly synchronize drawing and compute commands on the GPU.

The barrier defines the ordering of memory operations issued by a prior command. This means that if command1 is manipulating a buffer that is to be used as a vertex attribute buffer in a following command2, then the memory barrier should be placed after command1 and setting the appropriate barrier type for vertex attribute buffer.

When a QMemoryBarrier node is found in a FrameGraph branch, the barrier will be enforced prior to any draw or compute command even if these are defined deeper in the branch.

For OpenGL rendering, this page gives more info about the Memory Model

class PySide6.Qt3DRender.Qt3DRender.QMemoryBarrier([parent=None])

Parameters

parent – PySide6.Qt3DCore.Qt3DCore.QNode

PySide6.Qt3DRender.Qt3DRender.QMemoryBarrier.Operation

This enum type describes types of buffer to be cleared.

Constant	Description
Qt3DRender.QMemoryBarrier.None
Qt3DRender.QMemoryBarrier.ElementArray
Qt3DRender.QMemoryBarrier.Uniform
Qt3DRender.QMemoryBarrier.TextureFetch
Qt3DRender.QMemoryBarrier.ShaderImageAccess
Qt3DRender.QMemoryBarrier.Command
Qt3DRender.QMemoryBarrier.PixelBuffer
Qt3DRender.QMemoryBarrier.TextureUpdate
Qt3DRender.QMemoryBarrier.BufferUpdate
Qt3DRender.QMemoryBarrier.FrameBuffer
Qt3DRender.QMemoryBarrier.TransformFeedback
Qt3DRender.QMemoryBarrier.AtomicCounter
Qt3DRender.QMemoryBarrier.ShaderStorage
Qt3DRender.QMemoryBarrier.QueryBuffer
Qt3DRender.QMemoryBarrier.VertexAttributeArray
Qt3DRender.QMemoryBarrier.All

PySide6.Qt3DRender.Qt3DRender.QMemoryBarrier.setWaitOperations(operations)

Parameters

operations – Operations

PySide6.Qt3DRender.Qt3DRender.QMemoryBarrier.waitOperations()

Return type

Operations

PySide6.Qt3DRender.Qt3DRender.QMemoryBarrier.waitOperationsChanged(barrierTypes)

Parameters

barrierTypes – Operations