C Specification
The VkAccessFlagBits enums is defined as:
// Provided by VK_VERSION_1_0
typedef enum VkAccessFlagBits {
VK_ACCESS_INDIRECT_COMMAND_READ_BIT = 0x00000001,
VK_ACCESS_INDEX_READ_BIT = 0x00000002,
VK_ACCESS_VERTEX_ATTRIBUTE_READ_BIT = 0x00000004,
VK_ACCESS_UNIFORM_READ_BIT = 0x00000008,
VK_ACCESS_INPUT_ATTACHMENT_READ_BIT = 0x00000010,
VK_ACCESS_SHADER_READ_BIT = 0x00000020,
VK_ACCESS_SHADER_WRITE_BIT = 0x00000040,
VK_ACCESS_COLOR_ATTACHMENT_READ_BIT = 0x00000080,
VK_ACCESS_COLOR_ATTACHMENT_WRITE_BIT = 0x00000100,
VK_ACCESS_DEPTH_STENCIL_ATTACHMENT_READ_BIT = 0x00000200,
VK_ACCESS_DEPTH_STENCIL_ATTACHMENT_WRITE_BIT = 0x00000400,
VK_ACCESS_TRANSFER_READ_BIT = 0x00000800,
VK_ACCESS_TRANSFER_WRITE_BIT = 0x00001000,
VK_ACCESS_HOST_READ_BIT = 0x00002000,
VK_ACCESS_HOST_WRITE_BIT = 0x00004000,
VK_ACCESS_MEMORY_READ_BIT = 0x00008000,
VK_ACCESS_MEMORY_WRITE_BIT = 0x00010000,
// Provided by VK_EXT_transform_feedback
VK_ACCESS_TRANSFORM_FEEDBACK_WRITE_BIT_EXT = 0x02000000,
// Provided by VK_EXT_transform_feedback
VK_ACCESS_TRANSFORM_FEEDBACK_COUNTER_READ_BIT_EXT = 0x04000000,
// Provided by VK_EXT_transform_feedback
VK_ACCESS_TRANSFORM_FEEDBACK_COUNTER_WRITE_BIT_EXT = 0x08000000,
// Provided by VK_EXT_conditional_rendering
VK_ACCESS_CONDITIONAL_RENDERING_READ_BIT_EXT = 0x00100000,
// Provided by VK_EXT_blend_operation_advanced
VK_ACCESS_COLOR_ATTACHMENT_READ_NONCOHERENT_BIT_EXT = 0x00080000,
// Provided by VK_KHR_ray_tracing
VK_ACCESS_ACCELERATION_STRUCTURE_READ_BIT_KHR = 0x00200000,
// Provided by VK_KHR_ray_tracing
VK_ACCESS_ACCELERATION_STRUCTURE_WRITE_BIT_KHR = 0x00400000,
// Provided by VK_NV_shading_rate_image
VK_ACCESS_SHADING_RATE_IMAGE_READ_BIT_NV = 0x00800000,
// Provided by VK_EXT_fragment_density_map
VK_ACCESS_FRAGMENT_DENSITY_MAP_READ_BIT_EXT = 0x01000000,
// Provided by VK_NV_device_generated_commands
VK_ACCESS_COMMAND_PREPROCESS_READ_BIT_NV = 0x00020000,
// Provided by VK_NV_device_generated_commands
VK_ACCESS_COMMAND_PREPROCESS_WRITE_BIT_NV = 0x00040000,
// Provided by VK_NV_ray_tracing
VK_ACCESS_ACCELERATION_STRUCTURE_READ_BIT_NV = VK_ACCESS_ACCELERATION_STRUCTURE_READ_BIT_KHR,
// Provided by VK_NV_ray_tracing
VK_ACCESS_ACCELERATION_STRUCTURE_WRITE_BIT_NV = VK_ACCESS_ACCELERATION_STRUCTURE_WRITE_BIT_KHR,
// Provided by VK_KHR_fragment_shading_rate
VK_ACCESS_FRAGMENT_SHADING_RATE_ATTACHMENT_READ_BIT_KHR = VK_ACCESS_SHADING_RATE_IMAGE_READ_BIT_NV,
} VkAccessFlagBits;Description
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VK_ACCESS_INDIRECT_COMMAND_READ_BITspecifies read access to indirect command data read as part of an indirect drawing or dispatch command. -
VK_ACCESS_INDEX_READ_BITspecifies read access to an index buffer as part of an indexed drawing command, bound by vkCmdBindIndexBuffer. -
VK_ACCESS_VERTEX_ATTRIBUTE_READ_BITspecifies read access to a vertex buffer as part of a drawing command, bound by vkCmdBindVertexBuffers. -
VK_ACCESS_UNIFORM_READ_BITspecifies read access to a uniform buffer. -
VK_ACCESS_INPUT_ATTACHMENT_READ_BITspecifies read access to an input attachment within a render pass during fragment shading. -
VK_ACCESS_SHADER_READ_BITspecifies read access to a storage buffer, physical storage buffer, shader binding table, uniform texel buffer, storage texel buffer, sampled image, or storage image. -
VK_ACCESS_SHADER_WRITE_BITspecifies write access to a storage buffer, physical storage buffer, storage texel buffer, or storage image. -
VK_ACCESS_COLOR_ATTACHMENT_READ_BITspecifies read access to a color attachment, such as via blending, logic operations, or via certain subpass load operations. It does not include advanced blend operations. -
VK_ACCESS_COLOR_ATTACHMENT_WRITE_BITspecifies write access to a color, resolve, or depth/stencil resolve attachment during a render pass or via certain subpass load and store operations. -
VK_ACCESS_DEPTH_STENCIL_ATTACHMENT_READ_BITspecifies read access to a depth/stencil attachment, via depth or stencil operations or via certain subpass load operations. -
VK_ACCESS_DEPTH_STENCIL_ATTACHMENT_WRITE_BITspecifies write access to a depth/stencil attachment, via depth or stencil operations or via certain subpass load and store operations. -
VK_ACCESS_TRANSFER_READ_BITspecifies read access to an image or buffer in a copy operation. -
VK_ACCESS_TRANSFER_WRITE_BITspecifies write access to an image or buffer in a clear or copy operation. -
VK_ACCESS_HOST_READ_BITspecifies read access by a host operation. Accesses of this type are not performed through a resource, but directly on memory. -
VK_ACCESS_HOST_WRITE_BITspecifies write access by a host operation. Accesses of this type are not performed through a resource, but directly on memory. -
VK_ACCESS_MEMORY_READ_BITspecifies all read accesses. It is always valid in any access mask, and is treated as equivalent to setting allREADaccess flags that are valid where it is used. -
VK_ACCESS_MEMORY_WRITE_BITspecifies all write accesses. It is always valid in any access mask, and is treated as equivalent to setting allWRITEaccess flags that are valid where it is used. -
VK_ACCESS_CONDITIONAL_RENDERING_READ_BIT_EXTspecifies read access to a predicate as part of conditional rendering. -
VK_ACCESS_TRANSFORM_FEEDBACK_WRITE_BIT_EXTspecifies write access to a transform feedback buffer made when transform feedback is active. -
VK_ACCESS_TRANSFORM_FEEDBACK_COUNTER_READ_BIT_EXTspecifies read access to a transform feedback counter buffer which is read whenvkCmdBeginTransformFeedbackEXTexecutes. -
VK_ACCESS_TRANSFORM_FEEDBACK_COUNTER_WRITE_BIT_EXTspecifies write access to a transform feedback counter buffer which is written whenvkCmdEndTransformFeedbackEXTexecutes. -
VK_ACCESS_COMMAND_PREPROCESS_READ_BIT_NVspecifies reads fromVkBufferinputs to vkCmdPreprocessGeneratedCommandsNV. -
VK_ACCESS_COMMAND_PREPROCESS_WRITE_BIT_NVspecifies writes to theVkBufferpreprocess outputs in vkCmdPreprocessGeneratedCommandsNV. -
VK_ACCESS_COLOR_ATTACHMENT_READ_NONCOHERENT_BIT_EXTis similar toVK_ACCESS_COLOR_ATTACHMENT_READ_BIT, but also includes advanced blend operations. -
VK_ACCESS_FRAGMENT_SHADING_RATE_ATTACHMENT_READ_BIT_KHRspecifies read access to a fragment shading rate attachment or shading rate image during rasterization. -
VK_ACCESS_ACCELERATION_STRUCTURE_READ_BIT_KHRspecifies read access to an acceleration structure as part of a trace or build command, or to an acceleration structure scratch buffer as part of a build command. -
VK_ACCESS_ACCELERATION_STRUCTURE_WRITE_BIT_KHRspecifies write access to an acceleration structure or acceleration structure scratch buffer as part of a build command. -
VK_ACCESS_FRAGMENT_DENSITY_MAP_READ_BIT_EXTspecifies read access to a fragment density map attachment during dynamic fragment density map operations
Certain access types are only performed by a subset of pipeline stages. Any synchronization command that takes both stage masks and access masks uses both to define the access scopes - only the specified access types performed by the specified stages are included in the access scope. An application must not specify an access flag in a synchronization command if it does not include a pipeline stage in the corresponding stage mask that is able to perform accesses of that type. The following table lists, for each access flag, which pipeline stages can perform that type of access.
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Document Notes
For more information, see the Vulkan Specification
This page is extracted from the Vulkan Specification. Fixes and changes should be made to the Specification, not directly.