   zbuffer problems?
  I'm running slimdx and I have a shader that runs.  And for some reason the zbuffer is not appearing to work.  I have set zenable to true.  Is there some inherint problem in slimdx that stops it from performing standard zbuffer testing? So do I need to perform zbuffer testing in my hlsl program?   
  Firstly make sure zwriteenable and zfunc are also set appropriately.You don't need to do anything special in the hlsl.   ;  Thanks, I'll check that now.;  I think I found the problem. Its in the shader.  It calcs on a float4 which is causing trouble with the w coordinate in the vertex.  Can anyone help me figure out how to work on only a float3 instead of a float4, I just get errors.float4x4 wvp;float4x4 w;float4x4 v;float3 eyedir;float3 lightdir;float4 ambient;float4 linecolor;texture tex;sampler samp = sampler_state { texture = (tex); };struct vmI{float4 p : POSITION0;float3 n : NORMAL0;float4 c : COLOR0;float2 t : TEXCOORD0;};struct vmO{float4 p : POSITION0;float3 n : TEXCOORD1;float4 c : COLOR0;float2 t : TEXCOORD0;};struct pmI{float3 n : TEXCOORD1;float4 c : COLOR0;float2 t : TEXCOORD0;};vmO VShader(vmI i){vmO o;o.p = mul(i.p, wvp);//positiono.n = mul(i.n, w);//mul(i.n0, view);//normalo.c = i.c;//material diffuseo.t = i.t;//texture coordinate    return o;}float4 PShader(pmI i) : COLOR{   //normalize inputfloat3 ld = normalize(lightdir);float3 nd = normalize(i.n);float3 ed = normalize(eyedir);//calc diffuse component//float3 ref = ld - nd + nd;//float4 litpow = dot(ref, ed);float4 litpow = dot(nd, ld);float4 spec = litpow;// * i.c;//spec += ambient;//return the color compositionfloat4 o = spec;o.a = 1;//float4 s = tex2D(samp, i.t);//o *= s;return o;}technique Shader{pass p0{//BlendOp=Subtract;//SrcBlend=ONE;//DestBlend=DESTCOLOR;    //CullMode = CCW;//ZEnable = true;//ZWriteEnable = true;//Lighting = true;VertexShader = compile vs_2_0 VShader();PixelShader = compile ps_2_0 PShader();}}