   Basic HLSL Vertex Shader Problem
  Hi, I'm following the book, "3D Game Engine Programming" but instead of the assembly shaders, I want to implement HLSL shaders.I have used a few tutorials to set them up and am using a basic position HLSL shader from RenderMonkey. Here are the vertex and pixel shaders:float4x4 matViewProjection;struct VS_INPUT {   float4 Position : POSITION0;   };struct VS_OUTPUT {   float4 Position : POSITION0;   };VS_OUTPUT vs_main( VS_INPUT Input ){   VS_OUTPUT Output;   Output.Position = mul( matViewProjection, Input.Position ); return( Output );   }float4 ps_main() : COLOR0{ return( float4( 1.0f, 0.0f, 0.0f, 1.0f ) );   }When I run the program, the shaders compile fine and there are no complaints creating the shaders. However, I don't see any shapes ( I should see a box ). I have found that when rendering POINTS rather than SOLID, I can see one red point in the centre of the screen. As the pixel shader is set to change any input to red, I know the pixel shader is working.Perhaps there is something wrong with the way the vertices are sent to the shader?I think I am setting the matViewProjection correctly too.As I really have no idea where the problem is I can't post any more code. Just ask if you need to see more though.Help is much appreciated.All the best,Hugh Osborne   
  The lineOutput.Position = mul( matViewProjection, Input.Position );Should beOutput.Position = mul(float4(Input.Position.xyz,1.0f),matViewProjection);The order of multiplying a vertex by a matrix vs a matrix by a vertex matters, and the vertex must be in float4 format (even though yours is, the last value, the w-value, may not be 1.0f).Shawn   ;  Hmm, no joy i'm afraid. It's more likely to be something wrong with my code although I don't know what. I tried setting up assembly shaders ( NOT using RenderMoney "Disassembeld shaders" ) and that worked fine, everything rendered properly...   