ShaderModel与ES版本和GPU特性的关系

Opengl版本和功能的对应

Opengl网站

OpenGL 4.0 (2010)

OpenGL 3.3 (2010)

OpenGL 3.2 (2009)

• Core and compatibility profiles
• Shading language 1.50

OpenGL 3.1 (2009)

• All features deprecated in OpenGL 3.0 are removed except wide lines
• Shading language 1.40
• SNORM texture component formats

Microsoft对ShaderModel的定义

HLSL的ShaderModel主要表示不同版本的Shader支持的语言、功能特性。（The HLSL shader model is a versioning approach indicating which new features are added to the language.

应用和游戏可以针对某个版本通用的功能进行开发，硬件和驱动工程师也可以针对这个版本的特性进行支持。

不同的ShaderModel版本：不同的处理阶段（Geometry etc）、约束、处理能力、向下兼容情况。

• Shader Model 1. This was the first shader model created in DirectX. It introduced vertex and pixel shaders to the first implementation of the programmable pipeline.
• Shader Model 2. Adds new intrinsics and increases limits on registers and instructions.
• Shader Model 3. Adds new intrinsics and increases limits on registers and instructions.
• Shader Model 4. This is a superset of the capabilities in Shader Model 3, except that Shader Model 4 doesn’t support the features in Shader Model 1. It has been designed using a common-shader core that gives a common set of features to all programmable shaders, which are only programmable using HLSL. It adds new shader profiles to target geometry shaders.
• Shader Model 5. This is a superset of shader model 4 and adds new resources, compute shaders and tessellation.
• Shader Model 5.1. This is functionally very similar to Shader Model 5; the main change is more flexibility in resource selection by allowing indexing of arrays of descriptors from within a shader.
• Shader Model 6.0. This is a superset of shader model 5.1 with some deprecated language elements and with the addition of wave intrinsics and 64-bit integers for arithmetic.
• Shader Model 6.1. This is a superset of shader model 6.0 that adds support for SV_ViewID, barycentric semantics and the GetAttributeAtVertex intrinsic.
• Shader Model 6.2. Adds support for float16 (as opposed to minfloat16) and denorm mode selection.
• Shader Model 6.3. Adds support for DirectX Raytracing (DXR), including libraries and linking.
• Shader Model 6.4. Adds low-precision packed dot product intrinsics, and support for library sub-objects to simplify raytracing.

Differences between Direct3D 9 and Direct3D 10: Direct3D 9 introduced shader models 1, 2, and 3. Direct3D 10 introduced shader model 4. Direct3D 10.1 introduced shader model 4.1.

Unity对不同版本的定义

https://docs.unity3d.com/Manual/SL-ShaderCompileTargets.html

Here is the list of shader models supported, with roughly increasing set of capabilities (and in some cases higher platform/GPU requirements):

#pragma target 2.0

• Works on all platforms supported by Unity. DX9 shader model 2.0.
• Limited amount of arithmetic & texture instructions; 8 interpolators; no vertex texture sampling; no derivatives in fragment shaders ; no explicit LOD texture sampling.

#pragma target 2.5 (default)

• Almost the same as 3.0 target (see below), except still only has 8 interpolators, and does not have explicit LOD texture sampling.
• Compiles into DX11 feature level 9.3 on Windows Phone.

#pragma target 3.0

• DX9 shader model 3.0: derivative instructions, texture LOD sampling, 10 interpolators, more math/texture instructions allowed.
• Not supported on DX11 feature level 9.x GPUs (e.g. most Windows Phone devices).
• Might not be fully supported by some OpenGL ES 2.0 devices, depending on driver extensions present and features used.

#pragma target 3.5 (or es3.0)

• OpenGL ES 3.0 capabilities (DX10 SM4.0 on D3D platforms, just without geometry shaders).
• Not supported on DX11 9.x (WinPhone), OpenGL ES 2.0.
• Supported on DX11+, OpenGL 3.2+, OpenGL ES 3+, Metal, Vulkan, PS4/XB1 consoles.
• Native integer operations in shaders, texture arrays and so on.

#pragma target 4.0

• DX11 shader model 4.0.
• Not supported on DX11 9.x (WinPhone), OpenGL ES 2.0/3.0/3.1, Metal.
• Supported on DX11+, OpenGL 3.2+, OpenGL ES 3.1+AEP, Vulkan, PS4/XB1 consoles.
• Has geometry shaders and everything that es3.0 target has.

#pragma target 4.5 (or es3.1)

• OpenGL ES 3.1 capabilities (DX11 SM5.0 on D3D platforms, just without tessellation shaders).
• Not supported on DX11 before SM5.0, OpenGL before 4.3 (i.e. Mac), OpenGL ES 2.0/3.0.
• Supported on DX11+ SM5.0, OpenGL 4.3+, OpenGL ES 3.1, Metal, Vulkan, PS4/XB1 consoles.
• Has compute shaders, random access texture writes, atomics and so on. No geometry or tessellation shaders.

#pragma target 4.6 (or gl4.1)

• OpenGL 4.1 capabilities (DX11 SM5.0 on D3D platforms, just without compute shaders). This is basically the highest OpenGL level supported by Macs.
• Not supported on DX11 before SM5.0, OpenGL before 4.1, OpenGL ES 2.0/3.0/3.1, Metal.
• Supported on DX11+ SM5.0, OpenGL 4.1+, OpenGL ES 3.1+AEP, Vulkan, Metal (without geometry), PS4/XB1 consoles.

#pragma target 5.0

• DX11 shader model 5.0.
• Not supported on DX11 before SM5.0, OpenGL before 4.3 (i.e. Mac), OpenGL ES 2.0/3.0/3.1, Metal.
• Supported on DX11+ SM5.0, OpenGL 4.3+, OpenGL ES 3.1+AEP, Vulkan, Metal (without geometry), PS4/XB1 consoles.