error C2146 trying to compile a basic HLSL shader in C++ - c++

Question

i've just started to learn the basics of HLSL using C++, im following the tutorials on a book, the first basic shader is:
float4 VS_Main( float4 pos:POSITION):SV_POSITION
{
return pos;
}
but i get a lot of errors at compile time:
error C2146: syntax error: ';' missing before the identifier 'VS_Main'
error C4430: missing type specifier, int assumed. Note: default-int is no longer supported
error C2146: syntax error : ')' missing before the identifier 'pos'
error C2059: syntax errorlooks like a function definition, but there is no formal parameter list.
error C2059: syntax error: '{'
it really looks like the compiler cant handle HLSL at all...maybe VS2012 express doesnt support HLSL?
thanks in advance

Answer 1

HLSL is not C++. You should compile shaders with shader compiler, and C++ with C++ compiler — do not mix. There are two options for compiling HLSL.
Use command-line utility fxc.exe that is included in DirectX SDK (docs and usage here at MSDN). It generates a file that you should load in runtime by some of the ways described here.
Compile your shader at runtime by using D3DCompileFromFile function.
There are pros and cons about each of the variants. In short, pre-compiling at build time gives you some time gain at runtime, while compiling at runtime is more flexible and comfortable at development stage (no need to remember to recompile it or to use post-build scripts) but is more error-prone. Choose by yourself.

Answer 2

The code looks fine for HLSL. If you want to compile it from within VS2012 set the ".fx" file to build using the HLSL shader compiler. Right click the file select properties. Then select General and Item Type should be set to HLSL compiler.
If you really want to make shaders using C++ you could look into C++AMP to see if it may suit your needs.

Answer 3

it really looks like the compiler cant handle HLSL at all...maybe VS2012 express doesnt support HLSL?
No C++ compiler does. It is not supposed to be handled by the compiler.
You need to turn it into a resource and copy it into the bin directory using post-build scripts, and load the HLSL at runtime.
See also: http://www.directxtutorial.com/Lesson.aspx?lessonid=11-4-5