dst = texture_sample(unit, coord, bias)
+ for array textures src0.y contains the slice for 1D,
+ and src0.z contain the slice for 2D.
+ for shadow textures with no arrays, src0.z contains
+ the reference value.
+ for shadow textures with arrays, src0.z contains
+ the reference value for 1D arrays, and src0.w contains
+ the reference value for 2D arrays.
+ There is no way to pass a bias in the .w value for
+ shadow arrays, and GLSL doesn't allow this.
+ GLSL does allow cube shadows maps to take a bias value,
+ and we have to determine how this will look in TGSI.
.. opcode:: TXD - Texture Lookup with Derivatives
dst.w = src0.w \oplus src1.w
+.. opcode:: UCMP - Integer Conditional Move
+
+.. math::
+
+ dst.x = src0.x ? src1.x : src2.x
+
+ dst.y = src0.y ? src1.y : src2.y
+
+ dst.z = src0.z ? src1.z : src2.z
+
+ dst.w = src0.w ? src1.w : src2.w
+
+
+.. opcode:: UARL - Integer Address Register Load
+
+ Moves the contents of the source register, assumed to be an integer, into the
+ destination register, which is assumed to be an address (ADDR) register.
+
+
+.. opcode:: IABS - Integer Absolute Value
+
+.. math::
+
+ dst.x = |src.x|
+
+ dst.y = |src.y|
+
+ dst.z = |src.z|
+
+ dst.w = |src.w|
+
+
.. opcode:: SAD - Sum Of Absolute Differences
.. math::
dst.w = |src0.w - src1.w| + src2.w
-.. opcode:: TXF - Texel Fetch
+.. opcode:: TXF - Texel Fetch (as per NV_gpu_shader4), extract a single texel
+ from a specified texture image. The source sampler may
+ not be a CUBE or SHADOW.
+ src 0 is a four-component signed integer vector used to
+ identify the single texel accessed. 3 components + level.
+ src 1 is a 3 component constant signed integer vector,
+ with each component only have a range of
+ -8..+8 (hw only seems to deal with this range, interface
+ allows for up to unsigned int).
+ TXF(uint_vec coord, int_vec offset).
- TBD
+.. opcode:: TXQ - Texture Size Query (as per NV_gpu_program4)
+ retrieve the dimensions of the texture
+ depending on the target. For 1D (width), 2D/RECT/CUBE
+ (width, height), 3D (width, height, depth),
+ 1D array (width, layers), 2D array (width, height, layers)
-.. opcode:: TXQ - Texture Size Query
+.. math::
- TBD
+ lod = src0
+
+ dst.x = texture_width(unit, lod)
+
+ dst.y = texture_height(unit, lod)
+
+ dst.z = texture_depth(unit, lod)
.. opcode:: CONT - Continue
dst.zw = \sqrt{src.zw}
-.. _resourceopcodes:
+.. _samplingopcodes:
-Resource Access Opcodes
-^^^^^^^^^^^^^^^^^^^^^^^^
+Resource Sampling Opcodes
+^^^^^^^^^^^^^^^^^^^^^^^^^
Those opcodes follow very closely semantics of the respective Direct3D
instructions. If in doubt double check Direct3D documentation.
-.. opcode:: LOAD - Simplified alternative to the "SAMPLE" instruction.
- Using the provided integer address, LOAD fetches data
- from the specified buffer/texture without any filtering.
- The source data may come from any resource type other
- than CUBE.
- LOAD dst, address, resource
- e.g.
- LOAD TEMP[0], TEMP[1], RES[0]
-
-.. opcode:: LOAD_MS - Just like LOAD but allows fetch data from
- multi-sampled surfaces.
-
.. opcode:: SAMPLE - Using provided address, sample data from the
specified texture using the filtering mode identified
by the gven sampler. The source data may come from
any resource type other than buffers.
- SAMPLE dst, address, resource, sampler
+ SAMPLE dst, address, sampler_view, sampler
+ e.g.
+ SAMPLE TEMP[0], TEMP[1], SVIEW[0], SAMP[0]
+
+.. opcode:: SAMPLE_I - Simplified alternative to the SAMPLE instruction.
+ Using the provided integer address, SAMPLE_I fetches data
+ from the specified sampler view without any filtering.
+ The source data may come from any resource type other
+ than CUBE.
+ SAMPLE_I dst, address, sampler_view
e.g.
- SAMPLE TEMP[0], TEMP[1], RES[0], SAMP[0]
+ SAMPLE_I TEMP[0], TEMP[1], SVIEW[0]
+ The 'address' is specified as unsigned integers. If the
+ 'address' is out of range [0...(# texels - 1)] the
+ result of the fetch is always 0 in all components.
+ As such the instruction doesn't honor address wrap
+ modes, in cases where that behavior is desirable
+ 'SAMPLE' instruction should be used.
+ address.w always provides an unsigned integer mipmap
+ level. If the value is out of the range then the
+ instruction always returns 0 in all components.
+ address.yz are ignored for buffers and 1d textures.
+ address.z is ignored for 1d texture arrays and 2d
+ textures.
+ For 1D texture arrays address.y provides the array
+ index (also as unsigned integer). If the value is
+ out of the range of available array indices
+ [0... (array size - 1)] then the opcode always returns
+ 0 in all components.
+ For 2D texture arrays address.z provides the array
+ index, otherwise it exhibits the same behavior as in
+ the case for 1D texture arrays.
+ The exact semantics of the source address are presented
+ in the table below:
+ resource type X Y Z W
+ ------------- ------------------------
+ PIPE_BUFFER x ignored
+ PIPE_TEXTURE_1D x mpl
+ PIPE_TEXTURE_2D x y mpl
+ PIPE_TEXTURE_3D x y z mpl
+ PIPE_TEXTURE_RECT x y mpl
+ PIPE_TEXTURE_CUBE not allowed as source
+ PIPE_TEXTURE_1D_ARRAY x idx mpl
+ PIPE_TEXTURE_2D_ARRAY x y idx mpl
+
+ Where 'mpl' is a mipmap level and 'idx' is the
+ array index.
+
+.. opcode:: SAMPLE_I_MS - Just like SAMPLE_I but allows fetch data from
+ multi-sampled surfaces.
.. opcode:: SAMPLE_B - Just like the SAMPLE instruction with the
exception that an additiona bias is applied to the
level of detail computed as part of the instruction
execution.
- SAMPLE_B dst, address, resource, sampler, lod_bias
+ SAMPLE_B dst, address, sampler_view, sampler, lod_bias
e.g.
- SAMPLE_B TEMP[0], TEMP[1], RES[0], SAMP[0], TEMP[2].x
+ SAMPLE_B TEMP[0], TEMP[1], SVIEW[0], SAMP[0], TEMP[2].x
-.. opcode:: SAMPLE_C - Similar to the SAMPLE instruction but it
+.. opcode:: SAMPLE_C - Similar to the SAMPLE instruction but it
performs a comparison filter. The operands to SAMPLE_C
are identical to SAMPLE, except that tere is an additional
float32 operand, reference value, which must be a register
reference value against the red component value for the
surce resource at each texel that the currently configured
texture filter covers based on the provided coordinates.
- SAMPLE_C dst, address, resource.r, sampler, ref_value
+ SAMPLE_C dst, address, sampler_view.r, sampler, ref_value
e.g.
- SAMPLE_C TEMP[0], TEMP[1], RES[0].r, SAMP[0], TEMP[2].x
+ SAMPLE_C TEMP[0], TEMP[1], SVIEW[0].r, SAMP[0], TEMP[2].x
.. opcode:: SAMPLE_C_LZ - Same as SAMPLE_C, but LOD is 0 and derivatives
are ignored. The LZ stands for level-zero.
- SAMPLE_C_LZ dst, address, resource.r, sampler, ref_value
+ SAMPLE_C_LZ dst, address, sampler_view.r, sampler, ref_value
e.g.
- SAMPLE_C_LZ TEMP[0], TEMP[1], RES[0].r, SAMP[0], TEMP[2].x
+ SAMPLE_C_LZ TEMP[0], TEMP[1], SVIEW[0].r, SAMP[0], TEMP[2].x
.. opcode:: SAMPLE_D - SAMPLE_D is identical to the SAMPLE opcode except
that the derivatives for the source address in the x
direction and the y direction are provided by extra
parameters.
- SAMPLE_D dst, address, resource, sampler, der_x, der_y
+ SAMPLE_D dst, address, sampler_view, sampler, der_x, der_y
e.g.
- SAMPLE_D TEMP[0], TEMP[1], RES[0], SAMP[0], TEMP[2], TEMP[3]
+ SAMPLE_D TEMP[0], TEMP[1], SVIEW[0], SAMP[0], TEMP[2], TEMP[3]
.. opcode:: SAMPLE_L - SAMPLE_L is identical to the SAMPLE opcode except
that the LOD is provided directly as a scalar value,
representing no anisotropy. Source addresses A channel
is used as the LOD.
- SAMPLE_L dst, address, resource, sampler
+ SAMPLE_L dst, address, sampler_view, sampler
e.g.
- SAMPLE_L TEMP[0], TEMP[1], RES[0], SAMP[0]
-
+ SAMPLE_L TEMP[0], TEMP[1], SVIEW[0], SAMP[0]
.. opcode:: GATHER4 - Gathers the four texels to be used in a bi-linear
filtering operation and packs them into a single register.
- Only woth with 2D, 2D array, cubemaps, and cubemaps arrays.
+ Only works with 2D, 2D array, cubemaps, and cubemaps arrays.
For 2D textures, only the addressing modes of the sampler and
the top level of any mip pyramid are used. Set W to zero.
It behaves like the SAMPLE instruction, but a filtered
sample is not generated. The four samples that contribute
- to filtering are places into xyzw in cunter-clockwise order,
+ to filtering are placed into xyzw in counter-clockwise order,
starting with the (u,v) texture coordinate delta at the
following locations (-, +), (+, +), (+, -), (-, -), where
the magnitude of the deltas are half a texel.
-.. opcode:: RESINFO - query the dimentions of a given input buffer.
+.. opcode:: SVIEWINFO - query the dimensions of a given sampler view.
dst receives width, height, depth or array size and
- total mip count (also can be slected by writemask).
- RESINFO dst, src_mip_level, resource
+ number of mipmap levels. The dst can have a writemask
+ which will specify what info is the caller interested
+ in.
+ SVIEWINFO dst, src_mip_level, sampler_view
e.g.
- RESINFO TEMP[0], TEMP[1].x, RES[0]
+ SVIEWINFO TEMP[0], TEMP[1].x, SVIEW[0]
+ src_mip_level is an unsigned integer scalar. If it's
+ out of range then returns 0 for width, height and
+ depth/array size but the total number of mipmap is
+ still returned correctly for the given sampler view.
+ The returned width, height and depth values are for
+ the mipmap level selected by the src_mip_level and
+ are in the number of texels.
+ For 1d texture array width is in dst.x, array size
+ is in dst.y and dst.zw are always 0.
.. opcode:: SAMPLE_POS - query the position of a given sample.
dst receives float4 (x, y, 0, 0) indicated where the
sample is located. If the resource is not a multi-sample
resource and not a render target, the result is 0.
-.. opcode:: SAMPLE_INFO - dst receives number of components in x.
- If the resource is not a multi-sample resource and
+.. opcode:: SAMPLE_INFO - dst receives number of samples in x.
+ If the resource is not a multi-sample resource and
not a render target, the result is 0.
+.. _resourceopcodes:
+
+Resource Access Opcodes
+^^^^^^^^^^^^^^^^^^^^^^^
+
+.. opcode:: LOAD - Fetch data from a shader resource
+
+ Syntax: ``LOAD dst, resource, address``
+
+ Example: ``LOAD TEMP[0], RES[0], TEMP[1]``
+
+ Using the provided integer address, LOAD fetches data
+ from the specified buffer or texture without any
+ filtering.
+
+ The 'address' is specified as a vector of unsigned
+ integers. If the 'address' is out of range the result
+ is unspecified.
+
+ Only the first mipmap level of a resource can be read
+ from using this instruction.
+
+ For 1D or 2D texture arrays, the array index is
+ provided as an unsigned integer in address.y or
+ address.z, respectively. address.yz are ignored for
+ buffers and 1D textures. address.z is ignored for 1D
+ texture arrays and 2D textures. address.w is always
+ ignored.
+
+
Explanation of symbols used
------------------------------
UsageMask field specifies which of the register components can be accessed
and is one of TGSI_WRITEMASK.
-Interpolate field is only valid for fragment shader INPUT register files.
-It specifes the way input is being interpolated by the rasteriser and is one
-of TGSI_INTERPOLATE.
-
If Dimension flag is set to 1, a Declaration Dimension token follows.
If Semantic flag is set to 1, a Declaration Semantic token follows.
-CylindricalWrap bitfield is only valid for fragment shader INPUT register
-files. It specifies which register components should be subject to cylindrical
-wrapping when interpolating by the rasteriser. If TGSI_CYLINDRICAL_WRAP_X
-is set to 1, the X component should be interpolated according to cylindrical
-wrapping rules.
+If Interpolate flag is set to 1, a Declaration Interpolate token follows.
If file is TGSI_FILE_RESOURCE, a Declaration Resource token follows.
This allows the fragment shader to change the fragments stencilref value.
-Declaration Resource
+Declaration Interpolate
+^^^^^^^^^^^^^^^^^^^^^^^
+
+This token is only valid for fragment shader INPUT declarations.
+
+The Interpolate field specifes the way input is being interpolated by
+the rasteriser and is one of TGSI_INTERPOLATE_*.
+
+The CylindricalWrap bitfield specifies which register components
+should be subject to cylindrical wrapping when interpolating by the
+rasteriser. If TGSI_CYLINDRICAL_WRAP_X is set to 1, the X component
+should be interpolated according to cylindrical wrapping rules.
+
+
+Declaration Sampler View
^^^^^^^^^^^^^^^^^^^^^^^^
+ Follows Declaration token if file is TGSI_FILE_SAMPLER_VIEW.
+
+ DCL SVIEW[#], resource, type(s)
+
+ Declares a shader input sampler view and assigns it to a SVIEW[#]
+ register.
+
+ resource can be one of BUFFER, 1D, 2D, 3D, 1DArray and 2DArray.
+
+ type must be 1 or 4 entries (if specifying on a per-component
+ level) out of UNORM, SNORM, SINT, UINT and FLOAT.
+
+
+Declaration Resource
+^^^^^^^^^^^^^^^^^^^^
+
Follows Declaration token if file is TGSI_FILE_RESOURCE.
- DCL RES[#], resource, type(s)
+ DCL RES[#], resource [, RAW]
Declares a shader input resource and assigns it to a RES[#]
register.
resource can be one of BUFFER, 1D, 2D, 3D, CUBE, 1DArray and
2DArray.
- type must be 1 or 4 entries (if specifying on a per-component
- level) out of UNORM, SNORM, SINT, UINT and FLOAT.
+ If the RAW keyword is not specified, the texture data will be
+ subject to conversion, swizzling and scaling as required to yield
+ the specified data type from the physical data format of the bound
+ resource.
+
+ If the RAW keyword is specified, no channel conversion will be
+ performed: the values read for each of the channels (X,Y,Z,W) will
+ correspond to consecutive words in the same order and format
+ they're found in memory. No element-to-address conversion will be
+ performed either: the value of the provided X coordinate will be
+ interpreted in byte units instead of texel units. The result of
+ accessing a misaligned address is undefined.
Properties
bound cbufs. This facilitates OpenGL's fragColor output vs fragData[0] where
fragData is directed to a single color buffer, but fragColor is broadcast.
+VS_PROHIBIT_UCPS
+""""""""""""""""""""""""""
+If this property is set on the program bound to the shader stage before the
+fragment shader, user clip planes should have no effect (be disabled) even if
+that shader does not write to any clip distance outputs and the rasterizer's
+clip_plane_enable is non-zero.
+This property is only supported by drivers that also support shader clip
+distance outputs.
+This is useful for APIs that don't have UCPs and where clip distances written
+by a shader cannot be disabled.
+
Texture Sampling and Texture Formats
------------------------------------
projects / mesa.git / blobdiff