Hello I use the same way to render sprites with directx from a long time but here I am rendering the screen in a texture and then render it with a big sprite on the screen.
For the camera I use that: vUpVec=D3DXVECTOR3(0,1,0); vLookatPt=D3DXVECTOR3(0,0,0); vFromPt=D3DXVECTOR3(0,0,-1);
D3DXMatrixLookAtRH( &matView, &vFromPt, &vLookatPt, &vUpVec );
g_pd3dDevice->SetTransform( D3DTS_VIEW, &matView );
D3DXMatrixOrthoRH( &matProj, 1,1, 0.5f, 20 );
g_pd3dDevice->SetTransform( D3DTS_PROJECTION, &matProj );
And to render the sprite: CUSTOMVERTEX* v; spritevb->Lock( 0, 0, (void**)&v, 0 );
v[0].position = D3DXVECTOR3(-0.5f,-0.5f,0); v[0].u=0; v[0].v=1;
v[1].position = D3DXVECTOR3(-0.5f,0.5f,0); v[1].u=0; v[1].v=0;
v[2].position = D3DXVECTOR3(0.5f,-0.5f,0); v[2].u=1; v[2].v=1;
v[3].position = D3DXVECTOR3(0.5f,0.5f,0); v[3].u=1; v[3].v=0;
spritevb->Unlock();
g_pd3dDevice->DrawPrimitive( D3DPT_TRIANGLESTRIP, 0, 2 );
This is very basic and works, my sprite is rendered on the screen full. But by looking closer I see that there's a small diagonal line through the screen (between the 2 polygons) not a colored one but like if them weren't perfectly positionned.
I thought about filtering and tried removing everything but maybe I forget something...
Thanks
To render to full screen best way is to not define any camera positions.
If you use as input positions
and in the Vertex Shader do
you get a render to full screen as well without having to worry about the viewing frustrum. Using this I never saw any lines between the two triangles.