High-Level Shader Language

Last updated

A scene containing several different 2D HLSL shaders. Distortion of the statue is achieved purely physically, while the texture of the rectangular frame beside it is based on color intensity. The square in the background has been transformed and rotated. The partial transparency and reflection of the water in the foreground are added by a shader applied finally to the entire scene. HLSL-Examples-1.PNG
A scene containing several different 2D HLSL shaders. Distortion of the statue is achieved purely physically, while the texture of the rectangular frame beside it is based on color intensity. The square in the background has been transformed and rotated. The partial transparency and reflection of the water in the foreground are added by a shader applied finally to the entire scene.

The High-Level Shader Language [1] or High-Level Shading Language [2] (HLSL) is a proprietary shading language developed by Microsoft for the Direct3D 9 API to augment the shader assembly language, and went on to become the required shading language for the unified shader model of Direct3D 10 and higher.

Contents

HLSL is analogous to the GLSL shading language used with the OpenGL standard. It is very similar to the Nvidia Cg shading language, as it was developed alongside it. Early versions of the two languages were considered identical, only marketed differently. [3] HLSL shaders can enable profound speed and detail increases as well as many special effects in both 2D and 3D computer graphics.[ citation needed ]

HLSL programs come in six forms: pixel shaders (fragment in GLSL), vertex shaders, geometry shaders, compute shaders, tessellation shaders (Hull and Domain shaders), and ray tracing shaders (Ray Generation Shaders, Intersection Shaders, Any Hit/Closest Hit/Miss Shaders). A vertex shader is executed for each vertex that is submitted by the application, and is primarily responsible for transforming the vertex from object space to view space, generating texture coordinates, and calculating lighting coefficients such as the vertex's normal, tangent, and bitangent vectors. When a group of vertices (normally 3, to form a triangle) come through the vertex shader, their output position is interpolated to form pixels within its area; this process is known as rasterization.

Optionally, an application using a Direct3D 10/11/12 interface and Direct3D 10/11/12 hardware may also specify a geometry shader. This shader takes as its input some vertices of a primitive (triangle/line/point) and uses this data to generate/degenerate (or tessellate) additional primitives or to change the type of primitives, which are each then sent to the rasterizer.

D3D11.3 and D3D12 introduced Shader Model 5.1 [4] and later 6.0. [5]

Shader model comparison

GPUs listed are the hardware that first supported the given specifications. Manufacturers generally support all lower shader models through drivers. Note that games may claim to require a certain DirectX version, but don't necessarily require a GPU conforming to the full specification of that version, as developers can use a higher DirectX API version to target lower-Direct3D-spec hardware; for instance DirectX 9 exposes features of DirectX7-level hardware that DirectX7 did not, targeting their fixed-function T&L pipeline.

Pixel shader comparison

Pixel shader version1.01.11.2

1.3 [6]

1.4 [6] 2.0 [6] [7] 2.0a [6] [7] [8] 2.0b [6] [7] [9] 3.0 [6] [10] 4.0 [11] 4.1 [12]

5.0 [13]

Dependent texture limit44468Unlimited8UnlimitedUnlimited
Texture instruction limit4446 * 232UnlimitedUnlimitedUnlimitedUnlimited
Arithmetic instruction limit8888 * 264UnlimitedUnlimitedUnlimitedUnlimited
Position registerNoNoNoNoNoNoNoYesYes
Instruction slots88 + 48 + 4(8 + 6) * 264 + 32512512≥ 512≥ 65536
Executed instructions88 + 48 + 4(8 + 6) * 264 + 3251251265536Unlimited
Texture indirections44444Unlimited4UnlimitedUnlimited
Interpolated registers2 + 42 + 42 + 42 + 62 + 82 + 82 + 81032
Instruction predicationNoNoNoNoNoYesNoYesNo
Index input registersNoNoNoNoNoNoNoYesYes
Temp registers22 + 43 + 4612 to 322232324096
Constant registers888832323222416×4096
Arbitrary swizzling NoNoNoNoNoYesNoYesYes
Gradient instructionsNoNoNoNoNoYesNoYesYes
Loop count registerNoNoNoNoNoNoNoYesYes
Face register (2-sided lighting)NoNoNoNoNoNoYesYesYes
Dynamic flow controlNoNoNoNoNoNoNoYes (24)Yes (64)
Bitwise OperatorsNoNoNoNoNoNoNoNoYes
Native IntegersNoNoNoNoNoNoNoNoYes


"32 + 64" for Executed Instructions means "32 texture instructions and 64 arithmetic instructions."

Vertex shader comparison

Vertex shader version1.01.1 [14] 2.0 [7] [14] [8] 2.0a [7] [14] [8] 3.0 [10] [14] 4.0 [11]
4.1 [12]
5.0 [13]
# of instruction slots128128256256≥ 512≥ 65536
Max # of instructions executed12812810246553665536Unlimited
Instruction predication NoNoNoYesYesYes
Temp registers12121216324096
# constant registers≥ 96≥ 96≥ 256256≥ 25616×4096
Address registerNoYesYesYesYesYes
Static flow controlNoNoYesYesYesYes
Dynamic flow controlNoNoNoYesYesYes
Dynamic flow control depth242464
Vertex texture fetchNoNoNoNoYesYes
# of texture samplers4128
Geometry instancing supportNoNoNoNoYesYes
Bitwise operatorsNoNoNoNoNoYes
Native integersNoNoNoNoNoYes

See also

Footnotes

  1. "Writing HLSL Shaders in Direct3D 9". Microsoft Docs . Retrieved February 22, 2021.
  2. "High-level shader language (HLSL)". Microsoft Docs . Retrieved February 22, 2021.
  3. "Fusion Industries :: Cg and HLSL FAQ ::". August 24, 2012. Archived from the original on August 24, 2012.
  4. "Shader Model 5.1 Objects". Microsoft Docs . Retrieved February 22, 2021.
  5. "HLSL Shader Model 6.0". Microsoft Docs . Retrieved February 22, 2021.
  6. 1 2 3 4 5 6 "Pixel Shader Differences". Microsoft Docs . August 19, 2020. Retrieved February 22, 2021.
  7. 1 2 3 4 5 Peeper, Craig; Mitchell, Jason L. (July 2003). "Introduction to the DirectX 9 High-Level Shader Language". Microsoft Docs . Retrieved February 22, 2021.
  8. 1 2 3 Shimpi, Anand Lal. "NVIDIA Introduces GeForce FX (NV30)". AnandTech . Retrieved February 22, 2021.
  9. Wilson, Derek. "ATI Radeon X800 Pro and XT Platinum Edition: R420 Arrives". AnandTech . Retrieved February 22, 2021.
  10. 1 2 Shader Model 3.0, Ashu Rege, NVIDIA Developer Technology Group, 2004.
  11. 1 2 The Direct3D 10 System, David Blythe, Microsoft Corporation, 2006.
  12. 1 2 "Registers - ps_4_1". Microsoft Docs . August 23, 2019. Retrieved February 22, 2021.
  13. 1 2 "Registers - ps_5_0". Microsoft Docs . August 23, 2019. Retrieved February 22, 2021.
  14. 1 2 3 4 "Vertex Shader Differences". Microsoft Docs . August 19, 2020. Retrieved February 22, 2021.