.. _screen:
Screen
======
A screen is an object representing the context-independent part of a device.
Flags and enumerations
----------------------
XXX some of these don't belong in this section.
.. _pipe_cap:
PIPE_CAP_*
^^^^^^^^^^
Capability queries return information about the features and limits of the
driver/GPU. For floating-point values, use :ref:`get_paramf`, and for boolean
or integer values, use :ref:`get_param`.
The integer capabilities:
* ``PIPE_CAP_NPOT_TEXTURES``: Whether :term:`NPOT` textures may have repeat modes,
normalized coordinates, and mipmaps.
* ``PIPE_CAP_TWO_SIDED_STENCIL``: Whether the stencil test can also affect back-facing
polygons.
* ``PIPE_CAP_MAX_DUAL_SOURCE_RENDER_TARGETS``: How many dual-source blend RTs are support.
:ref:`Blend` for more information.
* ``PIPE_CAP_ANISOTROPIC_FILTER``: Whether textures can be filtered anisotropically.
* ``PIPE_CAP_POINT_SPRITE``: Whether point sprites are available.
* ``PIPE_CAP_MAX_RENDER_TARGETS``: The maximum number of render targets that may be
bound.
* ``PIPE_CAP_OCCLUSION_QUERY``: Whether occlusion queries are available.
* ``PIPE_CAP_QUERY_TIME_ELAPSED``: Whether PIPE_QUERY_TIME_ELAPSED queries are available.
* ``PIPE_CAP_TEXTURE_SHADOW_MAP``: indicates whether the fragment shader hardware
can do the depth texture / Z comparison operation in TEX instructions
for shadow testing.
* ``PIPE_CAP_TEXTURE_SWIZZLE``: Whether swizzling through sampler views is
supported.
* ``PIPE_CAP_MAX_TEXTURE_2D_LEVELS``: The maximum number of mipmap levels available
for a 2D texture.
* ``PIPE_CAP_MAX_TEXTURE_3D_LEVELS``: The maximum number of mipmap levels available
for a 3D texture.
* ``PIPE_CAP_MAX_TEXTURE_CUBE_LEVELS``: The maximum number of mipmap levels available
for a cubemap.
* ``PIPE_CAP_TEXTURE_MIRROR_CLAMP``: Whether mirrored texture coordinates with clamp
are supported.
* ``PIPE_CAP_BLEND_EQUATION_SEPARATE``: Whether alpha blend equations may be different
from color blend equations, in :ref:`Blend` state.
* ``PIPE_CAP_SM3``: Whether the vertex shader and fragment shader support equivalent
opcodes to the Shader Model 3 specification. XXX oh god this is horrible
* ``PIPE_CAP_MAX_STREAM_OUTPUT_BUFFERS``: The maximum number of stream buffers.
* ``PIPE_CAP_PRIMITIVE_RESTART``: Whether primitive restart is supported.
* ``PIPE_CAP_INDEP_BLEND_ENABLE``: Whether per-rendertarget blend enabling and channel
masks are supported. If 0, then the first rendertarget's blend mask is
replicated across all MRTs.
* ``PIPE_CAP_INDEP_BLEND_FUNC``: Whether per-rendertarget blend functions are
available. If 0, then the first rendertarget's blend functions affect all
MRTs.
* ``PIPE_CAP_MAX_TEXTURE_ARRAY_LAYERS``: The maximum number of texture array
layers supported. If 0, the array textures are not supported at all and
the ARRAY texture targets are invalid.
* ``PIPE_CAP_TGSI_FS_COORD_ORIGIN_UPPER_LEFT``: Whether the TGSI property
FS_COORD_ORIGIN with value UPPER_LEFT is supported.
* ``PIPE_CAP_TGSI_FS_COORD_ORIGIN_LOWER_LEFT``: Whether the TGSI property
FS_COORD_ORIGIN with value LOWER_LEFT is supported.
* ``PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_HALF_INTEGER``: Whether the TGSI
property FS_COORD_PIXEL_CENTER with value HALF_INTEGER is supported.
* ``PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_INTEGER``: Whether the TGSI
property FS_COORD_PIXEL_CENTER with value INTEGER is supported.
* ``PIPE_CAP_DEPTH_CLIP_DISABLE``: Whether the driver is capable of disabling
depth clipping (through pipe_rasterizer_state)
* ``PIPE_CAP_SHADER_STENCIL_EXPORT``: Whether a stencil reference value can be
written from a fragment shader.
* ``PIPE_CAP_TGSI_INSTANCEID``: Whether TGSI_SEMANTIC_INSTANCEID is supported
in the vertex shader.
* ``PIPE_CAP_VERTEX_ELEMENT_INSTANCE_DIVISOR``: Whether the driver supports
per-instance vertex attribs.
* ``PIPE_CAP_FRAGMENT_COLOR_CLAMPED``: Whether fragment color clamping is
supported. That is, is the pipe_rasterizer_state::clamp_fragment_color
flag supported by the driver? If not, the state tracker will insert
clamping code into the fragment shaders when needed.
* ``PIPE_CAP_MIXED_COLORBUFFER_FORMATS``: Whether mixed colorbuffer formats are
supported, e.g. RGBA8 and RGBA32F as the first and second colorbuffer, resp.
* ``PIPE_CAP_VERTEX_COLOR_UNCLAMPED``: Whether the driver is capable of
outputting unclamped vertex colors from a vertex shader. If unsupported,
the vertex colors are always clamped. This is the default for DX9 hardware.
* ``PIPE_CAP_VERTEX_COLOR_CLAMPED``: Whether the driver is capable of
clamping vertex colors when they come out of a vertex shader, as specified
by the pipe_rasterizer_state::clamp_vertex_color flag. If unsupported,
the vertex colors are never clamped. This is the default for DX10 hardware.
If both clamped and unclamped CAPs are supported, the clamping can be
controlled through pipe_rasterizer_state. If the driver cannot do vertex
color clamping, the state tracker may insert clamping code into the vertex
shader.
* ``PIPE_CAP_GLSL_FEATURE_LEVEL``: Whether the driver supports features
equivalent to a specific GLSL version. E.g. for GLSL 1.3, report 130.
* ``PIPE_CAP_QUADS_FOLLOW_PROVOKING_VERTEX_CONVENTION``: Whether quads adhere to
the flatshade_first setting in ``pipe_rasterizer_state``.
* ``PIPE_CAP_USER_VERTEX_BUFFERS``: Whether the driver supports user vertex
buffers. If not, the state tracker must upload all data which is not in hw
resources. If user-space buffers are supported, the driver must also still
accept HW resource buffers.
* ``PIPE_CAP_VERTEX_BUFFER_OFFSET_4BYTE_ALIGNED_ONLY``: This CAP describes a hw
limitation. If true, pipe_vertex_buffer::buffer_offset must always be aligned
to 4. If false, there are no restrictions on the offset.
* ``PIPE_CAP_VERTEX_BUFFER_STRIDE_4BYTE_ALIGNED_ONLY``: This CAP describes a hw
limitation. If true, pipe_vertex_buffer::stride must always be aligned to 4.
If false, there are no restrictions on the stride.
* ``PIPE_CAP_VERTEX_ELEMENT_SRC_OFFSET_4BYTE_ALIGNED_ONLY``: This CAP describes
a hw limitation. If true, pipe_vertex_element::src_offset must always be
aligned to 4. If false, there are no restrictions on src_offset.
* ``PIPE_CAP_COMPUTE``: Whether the implementation supports the
compute entry points defined in pipe_context and pipe_screen.
* ``PIPE_CAP_USER_INDEX_BUFFERS``: Whether user index buffers are supported.
If not, the state tracker must upload all indices which are not in hw
resources. If user-space buffers are supported, the driver must also still
accept HW resource buffers.
* ``PIPE_CAP_USER_CONSTANT_BUFFERS``: Whether user-space constant buffers
are supported. If not, the state tracker must put constants into HW
resources/buffers. If user-space constant buffers are supported, the
driver must still accept HW constant buffers also.
* ``PIPE_CAP_CONSTANT_BUFFER_OFFSET_ALIGNMENT``: Describes the required
alignment of pipe_constant_buffer::buffer_offset.
* ``PIPE_CAP_START_INSTANCE``: Whether the driver supports
pipe_draw_info::start_instance.
* ``PIPE_CAP_QUERY_TIMESTAMP``: Whether PIPE_QUERY_TIMESTAMP and
the pipe_screen::get_timestamp hook are implemented.
* ``PIPE_CAP_TEXTURE_MULTISAMPLE``: Whether all MSAA resources supported
for rendering are also supported for texturing.
* ``PIPE_CAP_MIN_MAP_BUFFER_ALIGNMENT``: The minimum alignment that should be
expected for a pointer returned by transfer_map if the resource is
PIPE_BUFFER. In other words, the pointer returned by transfer_map is
always aligned to this value.
* ``PIPE_CAP_TEXTURE_BUFFER_OFFSET_ALIGNMENT``: Describes the required
alignment for pipe_sampler_view::u.buf.first_element, in bytes.
If a driver does not support first/last_element, it should return 0.
* ``PIPE_CAP_TGSI_TEXCOORD``: This CAP describes a hw limitation.
If true, the hardware cannot replace arbitrary shader inputs with sprite
coordinates and hence the inputs that are desired to be replaceable must
be declared with TGSI_SEMANTIC_TEXCOORD instead of TGSI_SEMANTIC_GENERIC.
The rasterizer's sprite_coord_enable state therefore also applies to the
TEXCOORD semantic.
Also, TGSI_SEMANTIC_PCOORD becomes available, which labels a fragment shader
input that will always be replaced with sprite coordinates.
* ``PIPE_CAP_PREFER_BLIT_BASED_TEXTURE_TRANSFER``: Whether it is preferable
to use a blit to implement a texture transfer which needs format conversions
and swizzling in state trackers. Generally, all hardware drivers with
dedicated memory should return 1 and all software rasterizers should return 0.
* ``PIPE_CAP_QUERY_PIPELINE_STATISTICS``: Whether PIPE_QUERY_PIPELINE_STATISTICS
is supported.
* ``PIPE_CAP_TEXTURE_BORDER_COLOR_QUIRK``: Bitmask indicating whether special
considerations have to be given to the interaction between the border color
in the sampler object and the sampler view used with it.
If PIPE_QUIRK_TEXTURE_BORDER_COLOR_SWIZZLE_R600 is set, the border color
may be affected in undefined ways for any kind of permutational swizzle
(any swizzle XYZW where X/Y/Z/W are not ZERO, ONE, or R/G/B/A respectively)
in the sampler view.
If PIPE_QUIRK_TEXTURE_BORDER_COLOR_SWIZZLE_NV50 is set, the border color
state should be swizzled manually according to the swizzle in the sampler
view it is intended to be used with, or herein undefined results may occur
for permutational swizzles.
* ``PIPE_CAP_MAX_TEXTURE_BUFFER_SIZE``: The maximum accessible size with
a buffer sampler view, in bytes.
* ``PIPE_CAP_MAX_VIEWPORTS``: The maximum number of viewports (and scissors
since they are linked) a driver can support. Returning 0 is equivalent
to returning 1 because every driver has to support at least a single
viewport/scissor combination.
* ``PIPE_CAP_ENDIANNESS``:: The endianness of the device. Either
PIPE_ENDIAN_BIG or PIPE_ENDIAN_LITTLE.
* ``PIPE_CAP_MIXED_FRAMEBUFFER_SIZES``: Whether it is allowed to have
different sizes for fb color/zs attachments. This controls whether
ARB_framebuffer_object is provided.
* ``PIPE_CAP_TGSI_VS_LAYER_VIEWPORT``: Whether ``TGSI_SEMANTIC_LAYER`` and
``TGSI_SEMANTIC_VIEWPORT_INDEX`` are supported as vertex shader
outputs. Note that the viewport will only be used if multiple viewports are
exposed.
* ``PIPE_CAP_MAX_GEOMETRY_OUTPUT_VERTICES``: The maximum number of vertices
output by a single invocation of a geometry shader.
* ``PIPE_CAP_MAX_GEOMETRY_TOTAL_OUTPUT_COMPONENTS``: The maximum number of
vertex components output by a single invocation of a geometry shader.
This is the product of the number of attribute components per vertex and
the number of output vertices.
* ``PIPE_CAP_MAX_TEXTURE_GATHER_COMPONENTS``: Max number of components
in format that texture gather can operate on. 1 == RED, ALPHA etc,
4 == All formats.
* ``PIPE_CAP_TEXTURE_GATHER_SM5``: Whether the texture gather
hardware implements the SM5 features, component selection,
shadow comparison, and run-time offsets.
* ``PIPE_CAP_BUFFER_MAP_PERSISTENT_COHERENT``: Whether
PIPE_TRANSFER_PERSISTENT and PIPE_TRANSFER_COHERENT are supported
for buffers.
* ``PIPE_CAP_TEXTURE_QUERY_LOD``: Whether the ``LODQ`` instruction is
supported.
* ``PIPE_CAP_MIN_TEXTURE_GATHER_OFFSET``: The minimum offset that can be used
in conjunction with a texture gather opcode.
* ``PIPE_CAP_MAX_TEXTURE_GATHER_OFFSET``: The maximum offset that can be used
in conjunction with a texture gather opcode.
* ``PIPE_CAP_SAMPLE_SHADING``: Whether there is support for per-sample
shading. The context->set_min_samples function will be expected to be
implemented.
* ``PIPE_CAP_TEXTURE_GATHER_OFFSETS``: Whether the ``TG4`` instruction can
accept 4 offsets.
* ``PIPE_CAP_TGSI_VS_WINDOW_SPACE_POSITION``: Whether
TGSI_PROPERTY_VS_WINDOW_SPACE_POSITION is supported, which disables clipping
and viewport transformation.
* ``PIPE_CAP_MAX_VERTEX_STREAMS``: The maximum number of vertex streams
supported by the geometry shader. If stream-out is supported, this should be
at least 1. If stream-out is not supported, this should be 0.
* ``PIPE_CAP_DRAW_INDIRECT``: Whether the driver supports taking draw arguments
{ count, instance_count, start, index_bias } from a PIPE_BUFFER resource.
See pipe_draw_info.
* ``PIPE_CAP_TGSI_FS_FINE_DERIVATIVE``: Whether the fragment shader supports
the FINE versions of DDX/DDY.
* ``PIPE_CAP_VENDOR_ID``: The vendor ID of the underlying hardware. If it's
not available one should return 0xFFFFFFFF.
* ``PIPE_CAP_DEVICE_ID``: The device ID (PCI ID) of the underlying hardware.
0xFFFFFFFF if not available.
* ``PIPE_CAP_ACCELERATED``: Whether the renderer is hardware accelerated.
* ``PIPE_CAP_VIDEO_MEMORY``: The amount of video memory in megabytes.
* ``PIPE_CAP_UMA``: If the device has a unified memory architecture or on-card
memory and GART.
* ``PIPE_CAP_CONDITIONAL_RENDER_INVERTED``: Whether the driver supports inverted
condition for conditional rendering.
* ``PIPE_CAP_MAX_VERTEX_ATTRIB_STRIDE``: The maximum supported vertex stride.
* ``PIPE_CAP_SAMPLER_VIEW_TARGET``: Whether the sampler view's target can be
different than the underlying resource's, as permitted by
ARB_texture_view. For example a 2d array texture may be reinterpreted as a
cube (array) texture and vice-versa.
* ``PIPE_CAP_CLIP_HALFZ``: Whether the driver supports the
pipe_rasterizer_state::clip_halfz being set to true. This is required
for enabling ARB_clip_control.
* ``PIPE_CAP_VERTEXID_NOBASE``: If true, the driver only supports
TGSI_SEMANTIC_VERTEXID_NOBASE (and not TGSI_SEMANTIC_VERTEXID). This means
state trackers for APIs whose vertexIDs are offset by basevertex (such as GL)
will need to lower TGSI_SEMANTIC_VERTEXID to TGSI_SEMANTIC_VERTEXID_NOBASE
and TGSI_SEMANTIC_BASEVERTEX, so drivers setting this must handle both these
semantics. Only relevant if geometry shaders are supported.
(Currently not possible to query availability of these two semantics outside
this, at least BASEVERTEX should be exposed separately too).
* ``PIPE_CAP_POLYGON_OFFSET_CLAMP``: If true, the driver implements support
for ``pipe_rasterizer_state::offset_clamp``.
* ``PIPE_CAP_MULTISAMPLE_Z_RESOLVE``: Whether the driver supports blitting
a multisampled depth buffer into a single-sampled texture (or depth buffer).
Only the first sampled should be copied.
* ``PIPE_CAP_RESOURCE_FROM_USER_MEMORY``: Whether the driver can create
a pipe_resource where an already-existing piece of (malloc'd) user memory
is used as its backing storage. In other words, whether the driver can map
existing user memory into the device address space for direct device access.
The create function is pipe_screen::resource_from_user_memory. The address
and size must be page-aligned.
* ``PIPE_CAP_DEVICE_RESET_STATUS_QUERY``:
Whether pipe_context::get_device_reset_status is implemented.
.. _pipe_capf:
PIPE_CAPF_*
^^^^^^^^^^^^^^^^
The floating-point capabilities are:
* ``PIPE_CAPF_MAX_LINE_WIDTH``: The maximum width of a regular line.
* ``PIPE_CAPF_MAX_LINE_WIDTH_AA``: The maximum width of a smoothed line.
* ``PIPE_CAPF_MAX_POINT_WIDTH``: The maximum width and height of a point.
* ``PIPE_CAPF_MAX_POINT_WIDTH_AA``: The maximum width and height of a smoothed point.
* ``PIPE_CAPF_MAX_TEXTURE_ANISOTROPY``: The maximum level of anisotropy that can be
applied to anisotropically filtered textures.
* ``PIPE_CAPF_MAX_TEXTURE_LOD_BIAS``: The maximum :term:`LOD` bias that may be applied
to filtered textures.
* ``PIPE_CAPF_GUARD_BAND_LEFT``,
``PIPE_CAPF_GUARD_BAND_TOP``,
``PIPE_CAPF_GUARD_BAND_RIGHT``,
``PIPE_CAPF_GUARD_BAND_BOTTOM``: TODO
.. _pipe_shader_cap:
PIPE_SHADER_CAP_*
^^^^^^^^^^^^^^^^^
These are per-shader-stage capabitity queries. Different shader stages may
support different features.
* ``PIPE_SHADER_CAP_MAX_INSTRUCTIONS``: The maximum number of instructions.
* ``PIPE_SHADER_CAP_MAX_ALU_INSTRUCTIONS``: The maximum number of arithmetic instructions.
* ``PIPE_SHADER_CAP_MAX_TEX_INSTRUCTIONS``: The maximum number of texture instructions.
* ``PIPE_SHADER_CAP_MAX_TEX_INDIRECTIONS``: The maximum number of texture indirections.
* ``PIPE_SHADER_CAP_MAX_CONTROL_FLOW_DEPTH``: The maximum nested control flow depth.
* ``PIPE_SHADER_CAP_MAX_INPUTS``: The maximum number of input registers.
* ``PIPE_SHADER_CAP_MAX_OUTPUTS``: The maximum number of output registers.
This is valid for all shaders except the fragment shader.
* ``PIPE_SHADER_CAP_MAX_CONST_BUFFER_SIZE``: The maximum size per constant buffer in bytes.
* ``PIPE_SHADER_CAP_MAX_CONST_BUFFERS``: Maximum number of constant buffers that can be bound
to any shader stage using ``set_constant_buffer``. If 0 or 1, the pipe will
only permit binding one constant buffer per shader, and the shaders will
not permit two-dimensional access to constants.
If a value greater than 0 is returned, the driver can have multiple
constant buffers bound to shader stages. The CONST register file can
be accessed with two-dimensional indices, like in the example below.
DCL CONST[0][0..7] # declare first 8 vectors of constbuf 0
DCL CONST[3][0] # declare first vector of constbuf 3
MOV OUT[0], CONST[0][3] # copy vector 3 of constbuf 0
For backwards compatibility, one-dimensional access to CONST register
file is still supported. In that case, the constbuf index is assumed
to be 0.
* ``PIPE_SHADER_CAP_MAX_TEMPS``: The maximum number of temporary registers.
* ``PIPE_SHADER_CAP_MAX_PREDS``: The maximum number of predicate registers.
* ``PIPE_SHADER_CAP_TGSI_CONT_SUPPORTED``: Whether the continue opcode is supported.
* ``PIPE_SHADER_CAP_INDIRECT_INPUT_ADDR``: Whether indirect addressing
of the input file is supported.
* ``PIPE_SHADER_CAP_INDIRECT_OUTPUT_ADDR``: Whether indirect addressing
of the output file is supported.
* ``PIPE_SHADER_CAP_INDIRECT_TEMP_ADDR``: Whether indirect addressing
of the temporary file is supported.
* ``PIPE_SHADER_CAP_INDIRECT_CONST_ADDR``: Whether indirect addressing
of the constant file is supported.
* ``PIPE_SHADER_CAP_SUBROUTINES``: Whether subroutines are supported, i.e.
BGNSUB, ENDSUB, CAL, and RET, including RET in the main block.
* ``PIPE_SHADER_CAP_INTEGERS``: Whether integer opcodes are supported.
If unsupported, only float opcodes are supported.
* ``PIPE_SHADER_CAP_MAX_TEXTURE_SAMPLERS``: The maximum number of texture
samplers.
* ``PIPE_SHADER_CAP_PREFERRED_IR``: Preferred representation of the
program. It should be one of the ``pipe_shader_ir`` enum values.
* ``PIPE_SHADER_CAP_MAX_SAMPLER_VIEWS``: The maximum number of texture
sampler views. Must not be lower than PIPE_SHADER_CAP_MAX_TEXTURE_SAMPLERS.
* ``PIPE_SHADER_CAP_DOUBLES``: Whether double precision floating-point
operations are supported.
* ``PIPE_SHADER_CAP_TGSI_DROUND_SUPPORTED``: Whether double precision rounding
is supported. If it is, DTRUNC/DCEIL/DFLR/DROUND opcodes may be used.
* ``PIPE_SHADER_CAP_TGSI_DFRACEXP_DLDEXP_SUPPORTED``: Whether DFRACEXP and
DLDEXP are supported.
* ``PIPE_SHADER_CAP_TGSI_FMA_SUPPORTED``: Whether FMA and DFMA (doubles only)
are supported.
.. _pipe_compute_cap:
PIPE_COMPUTE_CAP_*
^^^^^^^^^^^^^^^^^^
Compute-specific capabilities. They can be queried using
pipe_screen::get_compute_param.
* ``PIPE_COMPUTE_CAP_IR_TARGET``: A description of the target of the form
``processor-arch-manufacturer-os`` that will be passed on to the compiler.
This CAP is only relevant for drivers that specify PIPE_SHADER_IR_LLVM
or PIPE_SHADER_IR_NATIVE for their preferred IR.
Value type: null-terminated string.
* ``PIPE_COMPUTE_CAP_GRID_DIMENSION``: Number of supported dimensions
for grid and block coordinates. Value type: ``uint64_t``.
* ``PIPE_COMPUTE_CAP_MAX_GRID_SIZE``: Maximum grid size in block
units. Value type: ``uint64_t []``.
* ``PIPE_COMPUTE_CAP_MAX_BLOCK_SIZE``: Maximum block size in thread
units. Value type: ``uint64_t []``.
* ``PIPE_COMPUTE_CAP_MAX_THREADS_PER_BLOCK``: Maximum number of threads that
a single block can contain. Value type: ``uint64_t``.
This may be less than the product of the components of MAX_BLOCK_SIZE and is
usually limited by the number of threads that can be resident simultaneously
on a compute unit.
* ``PIPE_COMPUTE_CAP_MAX_GLOBAL_SIZE``: Maximum size of the GLOBAL
resource. Value type: ``uint64_t``.
* ``PIPE_COMPUTE_CAP_MAX_LOCAL_SIZE``: Maximum size of the LOCAL
resource. Value type: ``uint64_t``.
* ``PIPE_COMPUTE_CAP_MAX_PRIVATE_SIZE``: Maximum size of the PRIVATE
resource. Value type: ``uint64_t``.
* ``PIPE_COMPUTE_CAP_MAX_INPUT_SIZE``: Maximum size of the INPUT
resource. Value type: ``uint64_t``.
* ``PIPE_COMPUTE_CAP_MAX_MEM_ALLOC_SIZE``: Maximum size of a memory object
allocation in bytes. Value type: ``uint64_t``.
* ``PIPE_COMPUTE_CAP_MAX_CLOCK_FREQUENCY``: Maximum frequency of the GPU
clock in MHz. Value type: ``uint32_t``
* ``PIPE_COMPUTE_CAP_MAX_COMPUTE_UNITS``: Maximum number of compute units
Value type: ``uint32_t``
* ``PIPE_COMPUTE_CAP_IMAGES_SUPPORTED``: Whether images are supported
non-zero means yes, zero means no. Value type: ``uint32_t``
.. _pipe_bind:
PIPE_BIND_*
^^^^^^^^^^^
These flags indicate how a resource will be used and are specified at resource
creation time. Resources may be used in different roles
during their lifecycle. Bind flags are cumulative and may be combined to create
a resource which can be used for multiple things.
Depending on the pipe driver's memory management and these bind flags,
resources might be created and handled quite differently.
* ``PIPE_BIND_RENDER_TARGET``: A color buffer or pixel buffer which will be
rendered to. Any surface/resource attached to pipe_framebuffer_state::cbufs
must have this flag set.
* ``PIPE_BIND_DEPTH_STENCIL``: A depth (Z) buffer and/or stencil buffer. Any
depth/stencil surface/resource attached to pipe_framebuffer_state::zsbuf must
have this flag set.
* ``PIPE_BIND_BLENDABLE``: Used in conjunction with PIPE_BIND_RENDER_TARGET to
query whether a device supports blending for a given format.
If this flag is set, surface creation may fail if blending is not supported
for the specified format. If it is not set, a driver may choose to ignore
blending on surfaces with formats that would require emulation.
* ``PIPE_BIND_DISPLAY_TARGET``: A surface that can be presented to screen. Arguments to
pipe_screen::flush_front_buffer must have this flag set.
* ``PIPE_BIND_SAMPLER_VIEW``: A texture that may be sampled from in a fragment
or vertex shader.
* ``PIPE_BIND_VERTEX_BUFFER``: A vertex buffer.
* ``PIPE_BIND_INDEX_BUFFER``: An vertex index/element buffer.
* ``PIPE_BIND_CONSTANT_BUFFER``: A buffer of shader constants.
* ``PIPE_BIND_TRANSFER_WRITE``: A transfer object which will be written to.
* ``PIPE_BIND_TRANSFER_READ``: A transfer object which will be read from.
* ``PIPE_BIND_STREAM_OUTPUT``: A stream output buffer.
* ``PIPE_BIND_CUSTOM``:
* ``PIPE_BIND_SCANOUT``: A front color buffer or scanout buffer.
* ``PIPE_BIND_SHARED``: A sharable buffer that can be given to another
process.
* ``PIPE_BIND_GLOBAL``: A buffer that can be mapped into the global
address space of a compute program.
* ``PIPE_BIND_SHADER_RESOURCE``: A buffer or texture that can be
bound to the graphics pipeline as a shader resource.
* ``PIPE_BIND_COMPUTE_RESOURCE``: A buffer or texture that can be
bound to the compute program as a shader resource.
* ``PIPE_BIND_COMMAND_ARGS_BUFFER``: A buffer that may be sourced by the
GPU command processor. It can contain, for example, the arguments to
indirect draw calls.
.. _pipe_usage:
PIPE_USAGE_*
^^^^^^^^^^^^
The PIPE_USAGE enums are hints about the expected usage pattern of a resource.
Note that drivers must always support read and write CPU access at any time
no matter which hint they got.
* ``PIPE_USAGE_DEFAULT``: Optimized for fast GPU access.
* ``PIPE_USAGE_IMMUTABLE``: Optimized for fast GPU access and the resource is
not expected to be mapped or changed (even by the GPU) after the first upload.
* ``PIPE_USAGE_DYNAMIC``: Expect frequent write-only CPU access. What is
uploaded is expected to be used at least several times by the GPU.
* ``PIPE_USAGE_STREAM``: Expect frequent write-only CPU access. What is
uploaded is expected to be used only once by the GPU.
* ``PIPE_USAGE_STAGING``: Optimized for fast CPU access.
Methods
-------
XXX to-do
get_name
^^^^^^^^
Returns an identifying name for the screen.
get_vendor
^^^^^^^^^^
Returns the screen vendor.
get_device_vendor
^^^^^^^^^^^^^^^^^
Returns the actual vendor of the device driving the screen
(as opposed to the driver vendor).
.. _get_param:
get_param
^^^^^^^^^
Get an integer/boolean screen parameter.
**param** is one of the :ref:`PIPE_CAP` names.
.. _get_paramf:
get_paramf
^^^^^^^^^^
Get a floating-point screen parameter.
**param** is one of the :ref:`PIPE_CAP` names.
context_create
^^^^^^^^^^^^^^
Create a pipe_context.
**priv** is private data of the caller, which may be put to various
unspecified uses, typically to do with implementing swapbuffers
and/or front-buffer rendering.
is_format_supported
^^^^^^^^^^^^^^^^^^^
Determine if a resource in the given format can be used in a specific manner.
**format** the resource format
**target** one of the PIPE_TEXTURE_x flags
**sample_count** the number of samples. 0 and 1 mean no multisampling,
the maximum allowed legal value is 32.
**bindings** is a bitmask of :ref:`PIPE_BIND` flags.
**geom_flags** is a bitmask of PIPE_TEXTURE_GEOM_x flags.
Returns TRUE if all usages can be satisfied.
can_create_resource
^^^^^^^^^^^^^^^^^^^
Check if a resource can actually be created (but don't actually allocate any
memory). This is used to implement OpenGL's proxy textures. Typically, a
driver will simply check if the total size of the given resource is less than
some limit.
For PIPE_TEXTURE_CUBE, the pipe_resource::array_size field should be 6.
.. _resource_create:
resource_create
^^^^^^^^^^^^^^^
Create a new resource from a template.
The following fields of the pipe_resource must be specified in the template:
**target** one of the pipe_texture_target enums.
Note that PIPE_BUFFER and PIPE_TEXTURE_X are not really fundamentally different.
Modern APIs allow using buffers as shader resources.
**format** one of the pipe_format enums.
**width0** the width of the base mip level of the texture or size of the buffer.
**height0** the height of the base mip level of the texture
(1 for 1D or 1D array textures).
**depth0** the depth of the base mip level of the texture
(1 for everything else).
**array_size** the array size for 1D and 2D array textures.
For cube maps this must be 6, for other textures 1.
**last_level** the last mip map level present.
**nr_samples** the nr of msaa samples. 0 (or 1) specifies a resource
which isn't multisampled.
**usage** one of the PIPE_USAGE flags.
**bind** bitmask of the PIPE_BIND flags.
**flags** bitmask of PIPE_RESOURCE_FLAG flags.
resource_destroy
^^^^^^^^^^^^^^^^
Destroy a resource. A resource is destroyed if it has no more references.
get_timestamp
^^^^^^^^^^^^^
Query a timestamp in nanoseconds. The returned value should match
PIPE_QUERY_TIMESTAMP. This function returns immediately and doesn't
wait for rendering to complete (which cannot be achieved with queries).
get_driver_query_info
^^^^^^^^^^^^^^^^^^^^^
Return a driver-specific query. If the **info** parameter is NULL,
the number of available queries is returned. Otherwise, the driver
query at the specified **index** is returned in **info**.
The function returns non-zero on success.
The driver-specific query is described with the pipe_driver_query_info
structure.
get_driver_query_group_info
^^^^^^^^^^^^^^^^^^^^^^^^^^^
Return a driver-specific query group. If the **info** parameter is NULL,
the number of available groups is returned. Otherwise, the driver
query group at the specified **index** is returned in **info**.
The function returns non-zero on success.
The driver-specific query group is described with the
pipe_driver_query_group_info structure.