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OpenGL D3D9 & HLSL First Triangle (nothing appears on screen)

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I've been doing OpenGL for a while and decided to try out the DirectX API, so I've got a sample application that I'm trying to use to render my 'hello world' triangle, but it's not appearing on the screen.

I got it to show up using fixed pipeline commands, but once I tried with HLSL I wasn't able to get anything to appear. I've cobbled my code together from a bunch of random tutorials and API documentation, as I can't find a single comprehensive resource that explains how to link a hlsl shader to your directx program. I thought I had the basics of it down, but I'm sure I'm missing a simple step or two somewhere.

I stripped down my code to below, maybe someone can spot my error. I checked the HRESULT after every command and I do not get any errors, just an plain blue screen (the clear color). This should draw a white triangle right in the middle of the screen.

Also my project is ultimately a cross-API renderer, so I'm not interested in using the Effects framework, I'd like to manage my shader states myself.

Thanks for anyone who can help!

DX Code:

main(){
//snipped out windows init code

d3d->CreateDevice(D3DADAPTER_DEFAULT,
D3DDEVTYPE_HAL,
hWnd,
D3DCREATE_SOFTWARE_VERTEXPROCESSING,
&d3dpp,
&d3ddev);



#define VERTEXTYPE D3DFVF_XYZ
struct CUSTOMVERTEX
{
FLOAT x, y, z; // from the D3DFVF_XYZ flag
};

CUSTOMVERTEX MyVertices[] =
{
{-1.f, 0.f, 5.0f, },
{0, 1.f, 5.0f, },
{1.f, 0, 5.0f, },
};

LPDIRECT3DVERTEXBUFFER9 v_buffer;
d3ddev->CreateVertexBuffer(3*sizeof(CUSTOMVERTEX),
0,
VERTEXTYPE,
D3DPOOL_MANAGED,
&v_buffer,
NULL);

VOID* pVoid; // the void* we were talking about
v_buffer->Lock(0, 0, (void**)&pVoid, 0); // locks v_buffer, the buffer we made earlier
memcpy(pVoid, MyVertices, sizeof(MyVertices)); // copy vertices to the vertex buffer
v_buffer->Unlock(); // unlock v_buffer

D3DXMATRIX matProjection;

LPD3DXBUFFER vshader;
LPD3DXBUFFER pshader;

LPD3DXBUFFER errorMsgs;
LPD3DXCONSTANTTABLE vsConstantTable;
LPD3DXCONSTANTTABLE psConstantTable;
std::string filename = SHADER_PATH + std::string("DX9//singleColor.hlsl9.vs");
HRESULT hr;
if(FAILED(hr = D3DXCompileShaderFromFile(filename.c_str(),NULL,NULL,"main","vs_2_0",NULL,&vshader,&errorMsgs,&vsConstantTable))){
return 0;
}
filename = SHADER_PATH + std::string("DX9//singleColor.hlsl9.ps");
if(FAILED(hr = D3DXCompileShaderFromFile(filename.c_str(),NULL,NULL,"main","ps_2_0",NULL,&pshader,&errorMsgs,&psConstantTable))){
return 0;
}

IDirect3DVertexShader9* vs;
IDirect3DPixelShader9* ps;
if(FAILED(hr = d3ddev->CreateVertexShader((DWORD*)vshader->GetBufferPointer(),&vs))){return 0;}
if(FAILED(hr = d3ddev->CreatePixelShader((DWORD*)pshader->GetBufferPointer(),&ps))){return 0;}

D3DXHANDLE handle;
handle = vsConstantTable->GetConstantByName(NULL,"mvpMatrix");
if(FAILED(hr = d3ddev->SetVertexShader(vs))){return 0;}
if(FAILED(hr = d3ddev->SetPixelShader(ps))){return 0;}

D3DVERTEXELEMENT9 decl[] = {
{0,0, D3DDECLTYPE_FLOAT3, D3DDECLMETHOD_DEFAULT, D3DDECLUSAGE_POSITION, 0},
D3DDECL_END()
};
LPDIRECT3DVERTEXDECLARATION9 m_pVertexDeclaration;
if(FAILED(hr = d3ddev->CreateVertexDeclaration(decl,&m_pVertexDeclaration))){return 0;}
if(FAILED(hr = d3ddev->SetVertexDeclaration(m_pVertexDeclaration))){return 0;}
D3DXMatrixPerspectiveFovLH(&matProjection,D3DXToRadian(45.f),(float)WINDOW_WIDTH/WINDOW_HEIGHT,0.1f,100.0f);
D3DXMATRIX mvpMatrix = matProjection;
if(FAILED(hr = vsConstantTable->SetMatrix(d3ddev,handle,&mvpMatrix))){return 0;}

//render loop
while(TRUE)
{
//snipped message code

// clear the window to a deep blue
d3ddev->Clear(0, NULL, D3DCLEAR_TARGET, D3DCOLOR_XRGB(0, 40, 100), 1.0f, 0);
d3ddev->BeginScene(); // begins the 3D scene

if(FAILED(hr = d3ddev->SetStreamSource(0, v_buffer, 0, sizeof(CUSTOMVERTEX)))){return 0;}
if(FAILED(hr = d3ddev->DrawPrimitive(D3DPT_TRIANGLELIST, 0, 1))){return 0;}
if(FAILED(hr = d3ddev->EndScene())){return 0;} // ends the 3D scene
if(FAILED(hr = d3ddev->Present(NULL, NULL, NULL, NULL))){return 0;} // displays the created frame
}

d3ddev->Release(); // close and release the 3D device
d3d->Release(); // close and release Direct3D

return msg.wParam;
}




Vertex Shader

float4x4 mvpMatrix;

struct VS_IN
{
float3 Pos : POSITION;
};
struct VS_OUT
{
float4 Pos : POSITION;
};

VS_OUT main(VS_IN In) {

VS_OUT Out;
Out.Pos = mul (mvpMatrix, float4(In.Pos,1));
return Out;
}




Pixel Shader:


struct PS_IN
{
};

struct PS_OUT
{
float4 Color : COLOR;
};

PS_OUT main(PS_IN In){

PS_OUT Out;
Out.Color = float4(1,1,1,1);
return Out;
}


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Your mul(mvpMatrix, position) should be mul(position, mvpMatrix). This can differ depending on how you set up your matrices.

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Quote:
Original post by Erik Rufelt
Your mul(mvpMatrix, position) should be mul(position, mvpMatrix). This can differ depending on how you set up your matrices.


Thanks, that was it :D

Guess I've been in the habit of using column major matrices.

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