tag:blogger.com,1999:blog-32321530.post8331061218015629563..comments2023-03-28T07:30:48.442+00:00Comments on Randomchaos 3D Engine: Generic XNA - SM3 FogCharles Humphreyhttp://www.blogger.com/profile/10935746329039730399noreply@blogger.comBlogger3125tag:blogger.com,1999:blog-32321530.post-66096121478893603482007-08-20T09:10:00.000+00:002007-08-20T09:10:00.000+00:00SM 2.x is only the Vertex Shader, on the pixel sha...SM 2.x is only the Vertex Shader, on the pixel shader it is 2.0a and 2.0b, 2.0a is Nvidia Geforce FX only, and 2.0b is Radeon x700+ only. So you would ONLY use those in say, a fragment shader where it will actually run on.<BR/>SM 2.0 will run on Geforce FX and Radeon 9500+, whilst 2.0b will not run on the 9500, making it only good for programatically constructed/combined shaders where you can Chr0n1xhttps://www.blogger.com/profile/03234723061961548946noreply@blogger.comtag:blogger.com,1999:blog-32321530.post-51296197118284226822007-08-18T11:34:00.000+00:002007-08-18T11:34:00.000+00:00I call it SM3 fog as the method will work in SM3, ...I call it SM3 fog as the method will work in SM3, I am using SM2 as my laptop can't do SM3, if you set it as SM2 and compile for the 360 it wil compile as SM3 by default (I think).<BR/><BR/>Oops, thought it was 64 for each, any how the extra calcs are in the pixel shader so, as shown, if you exceed 64 (arithmetic) slots (SM2) then you can add another pass to do the fog.<BR/><BR/>Thanks for the Charles Humphreyhttps://www.blogger.com/profile/10935746329039730399noreply@blogger.comtag:blogger.com,1999:blog-32321530.post-33701989239122091882007-08-18T09:49:00.000+00:002007-08-18T09:49:00.000+00:00Why you call it SM 3 Fog, when you use SM 2.0? The...Why you call it SM 3 Fog, when you use SM 2.0? The instruction limits in SM 2.0 are 256 for Vertex Shader and 32 (texture) + 64 (arithmetic) for the Pixel Shader. If you use SM 2.x you got 96 to 512 instructions for the Pixel Shader depending on your hardware.Anonymousnoreply@blogger.com