Hello,

I am tringing to make a 2D sprite engine that uses a dynamic Vertex Buffer, but I can't tell if the way I'm adding vertex data to is is working. So I was wondering if there is any way I can use the Visual Studio 2010 debugger to find the value of each vetex in the Vertex buffer (to see if its being stored correctly)?

Just in case here is how I'm creating it:

//Called once during initialization 
if(FAILED( g_pd3dDevice->CreateVertexBuffer( s_nBatchSize * 4 * sizeof( SpriteVertex ), D3DUSAGE_DYNAMIC | D3DUSAGE_WRITEONLY, 
D3DFVF_SPRITEVERTEX, D3DPOOL_DEFAULT, &m_pVB, NULL ) ) )

SpriteVertex* pVertex;
		m_pVB->Lock(nRenderOffset, nSpritesToLock*4, (void**)&pVertex, 0);

//Use these variables to set the 4 verticies for each sprite (quad)
			//Set vertex 1
			pVertex->vPos = D3DXVECTOR3(vPos.x - 0.5f, vPos.y - 0.5f, fDepth);
			pVertex->Colour = tColour;
			pVertex->u1 = pTexture->GetTextureUMin();
			pVertex->v1 = pTexture->GetTextureVMin();
			pVertex++;
			//Set vertex 2
			pVertex->vPos = D3DXVECTOR3(vPos.x+vSize.x - 0.5f, vPos.y - 0.5f, fDepth);
			pVertex->Colour = tColour;
			pVertex->u1 = pTexture->GetTextureUMax();
			pVertex->v1 = pTexture->GetTextureVMin();
			pVertex++;
			//Set vertex 3
			pVertex->vPos = D3DXVECTOR3(vPos.x - 0.5f, vPos.y+vSize.y - 0.5f, fDepth);
			pVertex->Colour = tColour;
			pVertex->u1 = pTexture->GetTextureUMin();
			pVertex->v1 = pTexture->GetTextureVMax();
			pVertex++;
			//Set vertex 
			pVertex->vPos = D3DXVECTOR3(vPos.x+vSize.x - 0.5f, vPos.y+vSize.y - 0.5f, fDepth);
			pVertex->Colour = tColour;
			pVertex->u1 = pTexture->GetTextureUMax();
			pVertex->v1 = pTexture->GetTextureVMax();
			pVertex++;
		}

m_pVB->Unlock();

[quote name='Jason Z' timestamp='1358130572' post='5021254']
Are you seeing behavior that makes you think it isn't working correctly?
[/quote]

Well all the values are what they should be, but I'm just having trouble finding what part of the process isn't working. Nothing draws to the screen when I call drawIndexedPrimitive but the code is too big to put up here (I think)

The only way I have used VB's previously was by creating an array then using memcpy(); but I don't see how I can create an array out of the for loop I had above?

Put up a screenshot of all the PIX state values at the time of rendering.
Check the obvious: Is your viewport correct? Are your near/far planes correct? Is your culling correct? Is your depth negative when it should be positive or vice-versa? Is your world-view-project matrix orthogonal and correct? Is it of the correct handedness?

Post a PIX screenshot or 2 containing all of these values at the time of render.


L. Spiro

I've never used PIX, I have the SDK but have no idea how to use it? Do you mind explaining?

Yeah I havn't really touched the matrices, Stupid as this sounds I am just using the SetupMatracis(); from one of the SDK Tutorials, So it might be this.

How do I ensure the world view projection Matrix is Orthogonal and the correct handedness?

Currently I just have:

    D3DXMATRIXA16 matWorld;
    D3DXMatrixIdentity( &matWorld );
    D3DXMatrixRotationX( &matWorld, timeGetTime() / 1000.0f );
    g_pd3dDevice->SetTransform( D3DTS_WORLD,  &matWorld );

    D3DXVECTOR3 vEyePt( 0.0f, 0.0f, -70.0f );
    D3DXVECTOR3 vLookatPt( 0.0f, 0.0f, 0.0f );
    D3DXVECTOR3 vUpVec( 0.0f, 1.0f, 0.0f );
    D3DXMATRIXA16 matView;
    D3DXMatrixLookAtLH( &matView, &vEyePt, &vLookatPt, &vUpVec );
    g_pd3dDevice->SetTransform( D3DTS_VIEW, &matView );

    D3DXMATRIXA16 matProj;
    D3DXMatrixPerspectiveFovLH( &matProj, D3DX_PI / 4, 800.0f / 600.0f, 1.0f, 100.0f );
    g_pd3dDevice->SetTransform( D3DTS_PROJECTION, &matProj );

All my depths are 0 (by default) , is this a problem?

I have :

g_pd3dDevice->SetRenderState(D3DRS_CULLMODE, D3DCULL_NONE);

So I think it might be my matrices, so how do I ensure the world view projection Matrix is Orthogonal and the correct handedness?

Thanks

See below