高级着色器语言

高级着色器语言（即 HLSL，缩写自 High Level Shader Language[1] 或 High-Level Shading Language[2]），是由微軟擁有及開發的一種着色器語言，最初的开发是为了辅助 Direct3D 9 的着色器汇编语言，后成为 Direct3D 10 以来统一着色器模型（英语：Unified Shader Model）所必须的语言。

HLSL只能供微軟的Direct3D以及XNA使用。HLSL是GLSL的先辈，不能與OpenGL標準兼容。它跟Nvidia的Cg非常相似，是因为两个开发者曾经紧密合作。[3]

HLSL的主要作用為將一些複雜的圖像處理，快速而又有效率地在顯示卡上完成，與組合式或低階Shader Language相比，能降低在編寫複雜特殊效果時所發生編程錯誤的機會。

Shader model 比較

Pixel shader 比較

Pixel shader 版本 1.0 to 1.3[4] 1.4[4] 2.0[4][5] 2.0a[4][5] 2.0b[4][5] 3.0[4][6] 4.0[7] 4.1[8] 5.0[9]
Dependent texture limit 4 6 8 Unlimited 8 Unlimited Unlimited Unlimited Unlimited
Texture instruction limit 4 6*2 32 Unlimited Unlimited Unlimited Unlimited Unlimited Unlimited
Position register No No No No No Yes Yes Yes Yes
Instruction slots 8+4 8+4 32 + 64 512 512 ≥ 512 ≥ 65536 ≥ 65536 ≥ 65536
Executed instructions 8+4 6*2+8*2 32 + 64 512 512 65536 Unlimited Unlimited Unlimited
Texture indirections 4 4 4 Unlimited 4 Unlimited Unlimited Unlimited Unlimited
Interpolated registers 2 + 8 2 + 8 2 + 8 2 + 8 2 + 8 10 32 32 32
Instruction predication No No No Yes No Yes No No No
Index input registers No No No No No Yes Yes Yes Yes
Temp registers 2 6 12 to 32 22 32 32 4096 4096 4096
Constant registers 8 8 32 32 32 224 16x4096 16x4096 16x4096
Arbitrary swizzling No No No Yes No Yes Yes Yes Yes
Gradient instructions No No No Yes No Yes Yes Yes Yes
Loop count register No No No No No Yes Yes Yes Yes
Face register (2-sided lighting) No No No No No Yes Yes Yes Yes
Dynamic flow control No No No No No 24 Yes Yes Yes
Bitwise Operators No No No No No No Yes Yes Yes
Native Integers No No No No No No Yes Yes Yes
  • PS 2.0 = DirectX 9.0 original Shader Model 2 specification.
  • PS 2.0a = NVIDIA GeForce FX-optimized model.
  • PS 2.0b = ATI Radeon X700, X800, X850 shader model, DirectX 9.0b.
  • PS 3.0 = Shader Model 3.0.
  • PS 4.0 = Shader Model 4.0.
  • PS 4.1 = Shader Model 4.1.
  • PS 5.0 = Shader Model 5.0.

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


Vertex shader 比較

Vertex shader 版本 VS 1.1[10] VS 2.0[5][10] VS 2.0a[5][10] VS 3.0[6][10] VS 4.0[7] VS 4.1[11] VS 5.0[9]
# of instruction slots 128 256 256 ≥ 512 4096 4096 4096
Max # of instructions executed Unknown 65536 65536 65536 65536 65536 65536
Instruction predication No No Yes Yes Yes Yes Yes
Temp registers 12 12 13 32 4096 4096 4096
# constant registers ≥ 96 ≥ 256 ≥ 256 ≥ 256 16x4096 16x4096 16x4096
Static flow control ??? Yes Yes Yes Yes Yes Yes
Dynamic flow control No No Yes Yes Yes Yes Yes
Dynamic flow control depth No No 24 24 Yes Yes Yes
Vertex texture fetch No No No Yes Yes Yes Yes
# of texture samplers N/A N/A N/A 4 128 128 128
Geometry instancing support No No No Yes Yes Yes Yes
Bitwise operators No No No No Yes Yes Yes
Native integers No No No No Yes Yes Yes
  • VS 2.0 = DirectX 9.0 original Shader Model 2 specification.
  • VS 2.0a = NVIDIA GeForce FX-optimized model.
  • VS 3.0 = Shader Model 3.0.
    • Note that ATI X1000 series cards (e.g. X1900) does not support Vertex Texture Fetch, hence it does not fully comply with the VS 3.0 model. Instead, they offer a feature called "Render to Vertex Buffer (R2VB)" that provides functionality that is a superset of Vertex Texture Fetch.[12]
  • VS 4.0 = Shader Model 4.0.
  • VS 4.1 = Shader Model 4.1.
  • VS 5.0 = Shader Model 5.0.

範例

灰階貼圖用
  • 灰階值 = 0.3 x 紅 + 0.59 x 綠 + 0.11 x 藍
sampler2D Texture0;

float4 ps_main( float2 texCoord  : TEXCOORD0 ) : COLOR
{
   float4 _inColor = tex2D( Texture0, texCoord );
   float gray = 0.3*_inColor.x + 0.59*_inColor.y + 0.11*_inColor.z;
   float4 _outColor = float4(gray, gray, gray, 1.0);
   
   return _outColor;
}

注釋

  1. ^ Writing HLSL Shaders in Direct3D 9 (Windows). msdn.microsoft.com. [2018-06-25]. （原始内容存档于2018-06-25）. 
  2. ^ HLSL. MSDN. Microsoft. [5 January 2015]. （原始内容存档于2018-06-25）. 
  3. ^ Fusion Industries :: Cg and HLSL FAQ ::. 24 August 2012. （原始内容存档于24 August 2012）. 
  4. ^ 4.0 4.1 4.2 4.3 4.4 4.5 Pixel Shader Differences. msdn.microsoft.com. 2011-02-08 [2014-08-28]. （原始内容存档于2013-03-16）. 
  5. ^ 5.0 5.1 5.2 5.3 5.4 Peeper, Craig. Microsoft DirectX High Level Shader Language (HLSL) (PPT). microsoft.com: 5–8, 24–25. 2004-03-15. [永久失效連結]
  6. ^ 6.0 6.1 Shader Model 3.0, Ashu Rege, NVIDIA Developer Technology Group, 2004.
  7. ^ 7.0 7.1 The Direct3D 10 System, David Blythe, Microsoft Corporation, 2006.
  8. ^ 存档副本. [2014-08-28]. （原始内容存档于2015-12-01）. 
  9. ^ 9.0 9.1 存档副本. [2014-08-28]. （原始内容存档于2013-09-09）. 
  10. ^ 10.0 10.1 10.2 10.3 Vertex Shader Differences. msdn.microsoft.com. 2011-02-08 [2014-08-28]. （原始内容存档于2013-03-14）. 
  11. ^ 存档副本. [2014-08-28]. （原始内容存档于2014-05-16）. 
  12. ^ Radeon X1000 series lacks vertex texture fetch[1] （页面存档备份，存于互联网档案馆）

外部連結