Sign in to follow this  
LostSource

Vertices and Indices problem

Recommended Posts

Lang: DirectX, C++ Compiler: VS2005 I'm currently trying to draw a two sided pyramide (just two triangles connecting and 2 indices). Here is a picture of the pyramide I'm trying to draw. 2 sided pyramide The vertices that I have set are: Vertex* vertices; g_hTriangle->Lock(0, 0, (void**)&vertices, 0); vertices[0] = Vertex( 0.0f, 0.0f,-2.0f); vertices[1] = Vertex(-2.0f, 0.0f, 0.0f); vertices[2] = Vertex( 0.0f, 2.0f, 0.0f); vertices[3] = Vertex( 2.0f, 0.0f, 0.0f); g_hTriangle->Unlock(); and the indices I have set are: WORD* indices; g_hIndexBuffer->Lock(0, 0, (void**)&indices, 0); indices[0] = 0; indices[1] = 1; indices[2] = 2; indices[3] = 0; indices[4] = 2; indices[5] = 3; g_hIndexBuffer->Unlock(); The problem is that for some reason the Display() isn't able to draw the two connecting triangles at their indices. Here is the code for the with all the Setup() and Display() functions. Setup()
bool Setup() {
	g_hDevice->CreateVertexBuffer(4 * sizeof(Vertex), D3DUSAGE_WRITEONLY, Vertex::FVF, D3DPOOL_MANAGED, &g_hTriangle, 0);
	g_hDevice->CreateIndexBuffer(2 * sizeof(WORD), D3DUSAGE_WRITEONLY, D3DFMT_D16, D3DPOOL_MANAGED, &g_hIndexBuffer, 0);

	Vertex* vertices;
	
	g_hTriangle->Lock(0, 0, (void**)&vertices, 0);
	vertices[0] = Vertex( 0.0f, 0.0f,-2.0f);
	vertices[1] = Vertex(-2.0f, 0.0f, 0.0f);
	vertices[2] = Vertex( 0.0f, 2.0f, 0.0f);
	vertices[3] = Vertex( 2.0f, 0.0f, 0.0f);
	g_hTriangle->Unlock();

	WORD* indices;

	g_hIndexBuffer->Lock(0, 0, (void**)&indices, 0);
	indices[0] = 0; indices[1] = 1; indices[2] = 2;
	indices[3] = 0; indices[4] = 2; indices[5] = 3;
	g_hIndexBuffer->Unlock();

	D3DXVECTOR3 position(0.0f, 5.0f, -8.0f);
	D3DXVECTOR3 target(0.0f, 0.0f, 0.0f);
	D3DXVECTOR3 up(0.0f, 1.0f, 0.0f);
	D3DXMATRIX view;
	D3DXMatrixLookAtLH(&view, &position, &target, &up);
	g_hDevice->SetTransform(D3DTS_VIEW, &view);

	D3DXMATRIX projection;
	D3DXMatrixPerspectiveFovLH(&projection, D3DX_PI * 0.5f, 
		(float)g_nBufferWidth/(float)g_nBufferHeight, 1.0f, 1000.0f);
	g_hDevice->SetTransform(D3DTS_PROJECTION, &projection);

	g_hDevice->SetRenderState(D3DRS_FILLMODE, D3DFILL_WIREFRAME);

	return true;
}

Display()
bool Display(bool frame_rate) {
	if(g_hDevice) {
		g_hDevice->Clear(0, 0, D3DCLEAR_TARGET | D3DCLEAR_ZBUFFER, 0xffffffff, 1.0f, 0);
		g_hDevice->BeginScene();

		g_hDevice->SetStreamSource(0, g_hTriangle, 0, sizeof(Vertex));
		g_hDevice->SetIndices(g_hIndexBuffer);
		g_hDevice->SetFVF(Vertex::FVF);
		g_hDevice->DrawIndexedPrimitive(D3DPT_TRIANGLELIST, 0, 0, 4, 0, 6);

		g_hDevice->EndScene();
		g_hDevice->Present(0, 0, 0, 0);
	}
	else
		return false;

	return true;
}

Thank you ahead of time for your help.

Share this post


Link to post
Share on other sites
How do I disable Culling? Sorry, I'm still new to this. = /

Edit: g_hDevice->SetRenderState(D3DRS_CULLMODE, D3DCULL_NONE)?

Edit2: I tried that and it still didn't work. = / I'm learning this from a book and the book never disables culling. I really wounder what it is that is preventing it from rendering the triangles.

Edit3: I found one problem. The g_hDevice->DrawIndexedPrimitive(D3DPT_TRIANGLELIST, 0, 0, 4, 0, 6) function should be g_hDevice->DrawIndexedPrimitive(D3DPT_TRIANGLELIST, 0, 0, 4, 0, 2); Because I'm only rendering 2 triangles, not 6. = ]

[Edited by - LostSource on September 9, 2006 11:38:01 AM]

Share this post


Link to post
Share on other sites
Your call to create the index buffer is most certainly failing because you specified D3DFMT_D16 - a depth buffer format. You also aren't making the index buffer large enough to hold the six indices necessary to describe the pyramid.

If you would add error checking to your program or enable the Debug D3D runtime, you'd determine this right away. The DX Forum FAQ has a list of suggestions on how to troubleshoot your app when things don't work as expected. You might want to look at it.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

Sign in to follow this