   Drawing lines and textures problem !
  I figured out that the lines I was drawing on the screen dissapeared (or weren't at full brightness) when I used a color key with textures.Why ? Technical details :I'm using DrawPrimitive()and a D3DPT_LINELIST to draw some lines around.  Not ID3DXLINE.My FVF for the lines is :D3DFVF_BASEVERTEXLINE (D3DFVF_XYZ | D3DFVF_DIFFUSE)I'm drawing textured quads (using tri-strips) using alpha testing  :pDevice->SetRenderState(D3DRS_ALPHAFUNC, D3DCMP_GREATER );pDevice->SetRenderState(D3DRS_ALPHATESTENABLE, TRUE);I load my textures using :D3DXCreateTextureFromFileExand I use a colorKey  of 0xFFFFFFFF (white)My FVF for the this is :D3DFVF_BASEVERTEX (D3DFVF_XYZ | D3DFVF_DIFFUSE | D3DFVF_TEX1)   
  What is the order in which you're drawing them in? Lines first, or textures? Are the lines primitives, or textured? Are you setting your vertex shader when switching between the two?If that isn't the case, then try experimenting a little. Change the color key, load but don't draw the textures, etc...   