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I am trying to draw a cube in DirectX. However, I am getting the following error message;

D3D11 ERROR: ID3D11DeviceContext::DrawIndexed: Rasterization Unit is enabled (PixelShader is not NULL or Depth/Stencil test is enabled and RasterizedStream is not D3D11_SO_NO_RASTERIZED_STREAM) but position is not provided by the last shader before the Rasterization Unit. [ EXECUTION ERROR #362: DEVICE_DRAW_POSITION_NOT_PRESENT]

Here is the code for my shaders;

cbuffer WorldBuffer : register (b0)
{
    matrix World;
    matrix View;
    matrix Projection;
}

struct VS_OUTPUT
{
    float4 pos   : SV_POSITION;
    float4 color : COLOR0;
};

VS_OUTPUT VS(float4 pos : POSITION, float4 color : COLOR) : VS_OUTPUT_SEMANTICS
{
    VS_OUTPUT output = (VS_OUTPUT)0;
    output.pos = mul(pos, World);
    output.pos = mul(output.pos, View);
    output.pos = mul(output.pos, Projection);
    output.color = color;
    return output;
}

float4 PS(VS_OUTPUT input : VS_OUTPUT_SEMANTICS) : SV_TARGET
{
    return input.color;
}

Since I have given SV_POSITION semantic to VS_OUTPUT.pos, I think shader should be passing position, but it doesn't seem to work. How can I fix my shaders?


This is how I compile my shaders:

UINT flags = D3DCOMPILE_ENABLE_STRICTNESS | D3DCOMPILE_SKIP_OPTIMIZATION | D3DCOMPILE_DEBUG;

r = D3DCompileFromFile(L"shader.fx", NULL, NULL, "VS", "vs_5_0", flags, 0, &vertex_blob, &errMsg);
yasar
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  • You should not need VS_OUTPUT_SEMANTICS, since semantics are already set on a per field basis, after it can also depends if you set your pipeline correctly, but would need to see the c++ code for that. – mrvux Jan 14 '20 at 12:53
  • @catflier, removing `VS_OUTPUT_SEMANTICS` actually fixes the problem. Now I wonder why it would have any affect. – yasar Jan 14 '20 at 12:55

1 Answers1

2

When using :

VS_OUTPUT VS(float4 pos : POSITION, float4 color : COLOR) : VS_OUTPUT_SEMANTICS

VS_OUTPUT_SEMANTICS will actually override the per element semantics, so instead of outputting a struct like :

struct VS_OUTPUT
{
    float4 pos   : SV_POSITION;
    float4 color : COLOR0;
};

you actually output

struct VS_OUTPUT
{
    float4 pos   : VS_OUTPUT_SEMANTICS;
    float4 color : VS_OUTPUT_SEMANTICS;
};

When you call :

UINT flags = D3DCOMPILE_ENABLE_STRICTNESS | D3DCOMPILE_SKIP_OPTIMIZATION | D3DCOMPILE_DEBUG;

r = D3DCompileFromFile(L"shader.fx", NULL, NULL, "VS", "vs_5_0", flags, 0, &vertex_blob, &errMsg);

Even if the shader compiles, you should still look in errMsg, as the compiler might issue some warnings (which in this case will be) :

"semantics in type overriden by variable/function or enclosing type"

If can also be a good idea to call D3DDisassemble on the resulting blob, this can give you the resulting reflection data in a text form.

In your vertex shader case you will have (only relevant part):

// Input signature:
//
// Name                 Index   Mask Register SysValue  Format   Used
// -------------------- ----- ------ -------- -------- ------- ------
// POSITION                 0   xyzw        0     NONE   float   xyzw
// COLOR                    0   xyzw        1     NONE   float   xyzw
//
//
// Output signature:
//
// Name                 Index   Mask Register SysValue  Format   Used
// -------------------- ----- ------ -------- -------- ------- ------
// VS_OUTPUT_SEMANTICS      0   xyzw        0     NONE   float   xyzw
// VS_OUTPUT_SEMANTICS      1   xyzw        1     NONE   float   xyzw
//
mrvux
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