I am currently writing a 3D engine based on the official Direct3D 9 tutorial by Microsoft. I adopted the code to my engine, but I cannot get triangles get rendered. It would be kind if someone could take a look at my structure, maybe he sees the mistake that I cannot. I know it's much code, so I tried to leave unimportant stuff away. The mesh seems to be alright, so I guess the error appears when copying the mesh into the vertex buffer. The types I use are all based on the native ones. The vertices I use ---------------------------

struct Vertex
{
	type::real position[3];  // float
	type::color color;  // unsigned long
};

My Mesh class ---------------------------

class Mesh
{
	private:
		type::uint16 _lastvertex;
		Vertex *_vertices;
		type::uint16 _vertexcount;

	public:
		IDirect3DVertexBuffer9 *_data_direct3d9;

		Mesh(type::uint16 vertexcount);
		virtual ~Mesh();

		inline void addVertex(const Vertex &v) { _vertices[_lastvertex++]= v; }
		inline void addVertex(const type::real posx, const type::real posy, const type::real posz, const type::color color)
		{
			_vertices[_lastvertex].position[0]= posx;
			_vertices[_lastvertex].position[1]= posy;
			_vertices[_lastvertex].position[2]= posz;

			_vertices[_lastvertex].color= color;

			++_lastvertex;
		}

		inline type::uint16 getVertexCount() { return _vertexcount; }
		inline Vertex* getVertices() { return _vertices; }
		inline type::uint32 getVertexMemorySize() { return _vertexcount * sizeof(Vertex); }
};

My Mesh object ---------------------------

	// create our test mesh
	type::color clr= D3DCOLOR_XRGB(255, 0, 0);

	__testmesh= new Mesh(3);
	__testmesh->addVertex(150.0f,  50.0f, 0.5f, clr);
	__testmesh->addVertex(250.0f, 250.0f, 0.5f, clr);
	__testmesh->addVertex( 50.0f, 250.0f, 0.5f, clr);

The Direct3D 9 Renderer Class ---------------------------

class RendererDirect3D9 : public Renderer
{
	protected:
		const static DWORD __vertex_format= D3DFVF_XYZ|D3DFVF_DIFFUSE;

	protected:
		IDirect3D9 *_direct3d;
		IDirect3DDevice9 *_device;

	public:
		virtual void update();
		virtual void acquireMesh(Mesh *m);
};

The Direct3D 9 Renderer - The created mesh is copied to the vertex buffer ---------------------------

void RendererDirect3D9::acquireMesh(Mesh *m)
{
	if(_device->CreateVertexBuffer(m->getVertexMemorySize(), 0, __vertex_format, D3DPOOL_DEFAULT, &m->_data_direct3d9, 0) !=D3D_OK)
	{
		showError(L"Could not create vertex buffer");
		return;
	}

	void* verts;
	if(m->_data_direct3d9->Lock(0, m->getVertexMemorySize(), &verts, 0) !=D3D_OK)
	{
		showError(L"Could not lock vertex buffer");
		return;
	}

	memcpy(verts, m->getVertices(), m->getVertexMemorySize());

	m->_data_direct3d9->Unlock();
}

The Direct3D 9 Renderer - The mesh is rendered ---------------------------

void RendererDirect3D9::update()
{
	_device->Clear(0, 0, D3DCLEAR_TARGET, 0, 1.0f, 0);
	_device->BeginScene();

	//render
	_device->SetStreamSource(0, __testmesh->_data_direct3d9, 0, sizeof(Vertex));
	_device->SetFVF(__vertex_format);
	_device->DrawPrimitive(D3DPT_TRIANGLELIST, 0, __testmesh->getVertexCount() -2);

	_device->EndScene();

	_device->Present(0, 0, 0, 0);
}

cheers Daniel

Usually when my triangles never appear it could be any of these 3 things.

1) Lighting is turned on.
2) Camera is in the wrong position.
3) Culling is on and the triangle is facing wrong way.

"official Direct3D 9 tutorial by Microsoft"

where is this?

You don't mean those 6 tutorials that come in the SDK do you?

Quote:Original post by Anonymous Poster
You don't mean those 6 tutorials that come in the SDK do you?

Hey, how did you know that? ;)

Mastaba, I corrected the error with the vertex count, although it currently makes no difference. thx for that

JoeyBlow2, I checked all that. It seems like the error is the getVertices() function.

This is how the sample does it

struct CUSTOMVERTEX{    FLOAT x, y, z, rhw; // The transformed position for the vertex    DWORD color;        // The vertex color};// Our custom FVF, which describes our custom vertex structure#define D3DFVF_CUSTOMVERTEX (D3DFVF_XYZRHW|D3DFVF_DIFFUSE)    CUSTOMVERTEX vertices[] =    {        { 150.0f,  50.0f, 0.5f, 1.0f, 0xffff0000, }, // x, y, z, rhw, color        { 250.0f, 250.0f, 0.5f, 1.0f, 0xff00ff00, },        {  50.0f, 250.0f, 0.5f, 1.0f, 0xff00ffff, },    };memcpy( pVertices, vertices, sizeof(vertices) );

This is how I do it

struct Vertex{	type::real position[3];	type::color color;};__vertex_format= D3DFVF_XYZ|D3DFVF_DIFFUSE;_vertices= new Vertex[vertexcount];inline Vertex* getVertices() { return _vertices; }memcpy(verts, m->getVertices(), m->getVertexMemorySize());

As you can see, the getVertices() function returns a pointer to a structure and not the structure itself, but when I change that, I see something on the screen, but not what I'm supposed to see.

I tried the following:

inline Vertex getVertices() { return *_vertices; }memcpy(verts, &m->getVertices(), m->getVertexMemorySize());

Shouldn't that have solved the problem?

I got it finally working. I have to use the D3DFVF_XYZRHW vertex data.

The only thing I had to do was to change D3DFVF_XYZ|D3DFVF_DIFFUSE to D3DFVF_XYZRHW|D3DFVF_DIFFUSE and to add the 4th component to the position and suddenly, it worked.

If I understand this right, this is because I currently do no transformation (WorldViewProjection), so I have to deliver the fourth component which would be otherwise computed during the transformation.

But why is the fourth component required? Isn't that somehow only a scale of the world position? (1.0f, 1.0f, 1.0f, 0.5f) -> (2.0f, 2.0f, 2.0f, 1.0f)