how to render point sprites as correct spheres

I'm trying to render my fluid simulation(CUDA & DirectX 11) with liquid effect, I render particles as sprites

but I want to get this result

here is my geometry an pixel shader

1. [maxvertexcount(4)] 
2. void mainGS(point GSPS_INPUT gInput[1],inout TriangleStream<GSPS_OUTPUT> TriStream) 
3. { 
4.  
5.  
6.   float size = 0.065; 
7.   matrix mv = View; 
8.   float3 right  = normalize(float3(mv._11,mv._21,mv._31));  
9.   float3 up    = normalize(float3(mv._12,mv._22,mv._32)); 
10.   // 
11.   float3 posEye = mul( float4(gInput[0].Pos.xyz, 1.0),world).xyz; 
12.   // 
13.   float halfWidth  = size/length(posEye); 
14.   float halfHeight = size/length(posEye); 
15.   // 
16.   float4 v[4]; 
17.   v[0] = float4(gInput[0].Pos + halfWidth*right - halfHeight*up, 1.0f); 
18.   v[1] = float4(gInput[0].Pos + halfWidth*right + halfHeight*up, 1.0f); 
19.   v[2] = float4(gInput[0].Pos - halfWidth*right - halfHeight*up, 1.0f); 
20.   v[3] = float4(gInput[0].Pos - halfWidth*right + halfHeight*up, 1.0f); 
21.   // 
22.   // 
23.   GSPS_OUTPUT output; 
24.   [unroll] 
25.   for(int i=0; i<4; ++i) 
26.   { 
27.  
28.     // 
29.     output.Pos    = mul(v[i], View); 
30.     output.PosW    = (output.Pos.xyz); 
31.  
32.     output.Pos    = mul(output.Pos, Projection); 
33.     output.Tex    = gQuadTexC[i]; 
34.     TriStream.Append(output); 
35.   } 
36.   TriStream.RestartStrip(); 
37. } 
38.  
39. //pixel shader 
40.  
41. float4 PS(GSPS_OUTPUT input) : SV_TARGET 
42. { 
43.   float3 N; 
44.   N.xy = input.Tex*float2(2.0f,-2.0f) + float2(-1.0f,1.0f); 
45.   float mag = dot(N.xy, N.xy); 
46.   if (mag > 1.0)  
47.   { 
48.     discard; 
49.   } 
50.  
51.   N.z = sqrt(1.0f-mag); 
52.   N = N * 0.5 + 0.5; 
53.  
54.  
55.   float4 pixelPos = float4(input.PosW + N*(1/32), 1.0); 
56.   float4 clipSpacePos = mul(pixelPos, Projection); 
57.   float depthval = (clipSpacePos.z / clipSpacePos.w);