vertex fragment domain hull shader > tessellation with shadows

Heyho!

After a week of research regarding tessellation I managed to build a edge length based tessellation shader based on example shaders I found on the internetz.

I have another shader with working shadows. Now I want to combine both..

I understand how the flow through both shader works and tessellation itself works flawless, shadows too. But now I have a bit of a problem to understand how to attach the tessellation shader to unitys shadow pipeline.

I found this interesting post but they are talking about a geometry program shader
http://forum.unity3d.com/threads/is-it-possible-to-use-geometry-shader-with-surface-shaders.164905/

Is it the way to go to expand the unityCG and AutoLight cginc files? (which would be ok)

also adding a shadow collector and caster pass.

I have unity 4 and 5 on my hands but I guess it makes no difference, right?

I'm currently working on it but I have the feeling this is not thought through. Could someone with more knowledge check the above thread and explain if that's how it should be done? Is there definitely no support for something like TRANSFER_VERTEX_TO_FRAGMENT(o) for a hull - domain shader right now and in the near future?

cheers

 

ok to answer my own question. It is the way to go! It doesn't matter if he is using an geometry program. it's the same method.

So in very short (showing only the shadow relevant code) it is:

Code (CSharp):

1.  
2.  
3. /############### base pass
4.  
5. struct HullType
6. {
7.     float4 pos : SV_POSITION;
8.     float2 uv : TEXCOORD0;
9.     float3 normal : NORMAL;
10.     float4 tangent : TANGENT;
11.     float4 color: COLOR;
12. };
13.  
14. struct PixelInputType
15. {
16.     LIGHTING_COORDS(4,5)  
17. };
18. //--------------------------------------------------------------------------------------
19.  
20.  
21. //--------------------------------------------------------------------------------------
22. // Domain Shader - Geometry Pass
23. //--------------------------------------------------------------------------------------
24. [domain("tri")]
25. PixelInputType DS(ConstantOutputType input, float3 domainCoord : SV_DomainLocation, const OutputPatch<HullType, 3> patch)
26. {  
27.     TRANSFER_GEOM_TO_FRAGMENT(output, output.pos);
28. }
29. //--------------------------------------------------------------------------------------
30.  
31.  
32.  
33.  
34.  
35. // /############### collector / caster pass
36.  
37.  
38.  
39.        //--------------------------------------------------------------------------------------
40. // TYPEDEFS - Shadow Pass
41. //--------------------------------------------------------------------------------------
42.  
43. struct HullType_S
44. {
45.     #ifdef SHADOW_CASTER_PASS
46.         V2F_SHADOW_CASTER; // (this one blocks TexCoord 0 to 4 and defines pos) //float4 pos : SV_POSITION;
47.     #else
48.         V2F_SHADOW_COLLECTOR; // (this one blocks TexCoord 0 to 4 and defines pos) //float4 pos : SV_POSITION;
49.     #endif
50. };
51. struct PixelInputType_S
52. {
53.     #ifdef SHADOW_CASTER_PASS
54.         V2F_SHADOW_CASTER; // (this one blocks TexCoord 0 to 4 and defines pos) //float4 pos : SV_POSITION;
55.     #else
56.         V2F_SHADOW_COLLECTOR; // (this one blocks TexCoord 0 to 4 and defines pos) //float4 pos : SV_POSITION;
57.     #endif
58. };
59. //--------------------------------------------------------------------------------------
60.  
61.  
62. //--------------------------------------------------------------------------------------
63. // Domain Shader - Shadow Pass
64. //--------------------------------------------------------------------------------------
65. [domain("tri")]
66. PixelInputType_S DS_S(ConstantOutputType input, float3 domainCoord : SV_DomainLocation, const OutputPatch<HullType_S, 3> patch)
67. {      
68.  
69.     // here it makes a lot more sense but the method must fit the domain shader
70.     #if defined (SHADOW_COLLECTOR_PASS)    
71.         TRANSFER_SHADOW_COLLECTOR(output, vertexPosition)  
72.     #elif defined (SHADOW_CASTER_PASS)      
73.         TRANSFER_SHADOW_CASTER(output, vertexPosition)
74.     #endif
75.  
76.  
77. }
78. //--------------------------------------------------------------------------------------
79. //--------------------------------------------------------------------------------------
80. // Pixel Shader - Shadow Pass
81. //--------------------------------------------------------------------------------------
82.  
83. float4 PS_S(PixelInputType_S i) : COLOR
84. {
85.     #if defined (SHADOW_COLLECTOR_PASS)
86.         SHADOW_COLLECTOR_FRAGMENT(i)
87.     #elif defined (SHADOW_CASTER_PASS)  
88.         SHADOW_CASTER_FRAGMENT(i)
89.     #endif    
90. }
91.  
92.  
93.  

 

But I have another question: why does the shader doesn't render "multi_compile_fwdadd" correctly?


If I only output the Forward Add Pass like that

Code (CSharp):

1.  
2. ...
3. // forward add pass
4.     Pass {
5.         Name "FORWARDADD"    
6.         Tags {"LightMode" = "ForwardAdd"}
7.         //Blend One One
8.         //Blend Zero One // only ambient
9.         Blend One Zero     // only direct light
10.  
11.         CGPROGRAM
12.  
13. #pragma target 5.0      
14.      #pragma vertex VS  
15.      #pragma fragment PS
16.      #pragma hull HS  
17.      #pragma domain DS  
18.    
19.      #pragma multi_compile_fwdadd
20.      #pragma fragmentoption ARB_precision_hint_fastest
21.      #pragma only_renderers d3d11
22.      
23.      //----------------------------------------------------------
24.      #define UNITY_PASS_FORWARDADD
25.      #include "UnityCG.cginc"
26.      #include "cginc/DwarfMines_UnityCG.cginc"
27.      #include "AutoLight.cginc"
28.      #include "cginc/DwarfMines_AutoLight.cginc"
29.      //#include "Lighting.cginc"
30.      //----------------------------------------------------------
31.      
32.      sampler2D _MainTex;
33.      
34.      //-------------------------------------------------------
35.      uniform half _DisplacementFactor;  
36.      uniform half _StaticTessellationFactor;
37.      uniform half _MaxDynamicTesselation;
38.      
39.      #include "cginc/DwarfMines_Tessellation.cginc"
40.      //-------------------------------------------------------
41.      
42.  
43.      //--------------------------------------------------------------------------------------
44.      // Pixel Shader
45.      //--------------------------------------------------------------------------------------
46.      float4 PS(PixelInputType v) : COLOR
47.      {
48.         float4 returnColor = float4(0.0, 1.0, 0.0, 1.0);      
49.        
50.        float atten = LIGHT_ATTENUATION(v); // This gets you the attenuation + shadow value.
51.        
52.        float3 lightDirection;
53.        if (0.0f == _WorldSpaceLightPos0.w) // directional light?  
54.          lightDirection = normalize(float3(_WorldSpaceLightPos0.xyz));  
55.        else // point or spot light  
56.          lightDirection =  normalize(float3(_WorldSpaceLightPos0.xyz - v.pos.xyz));
57.          
58.        float lightIntensity = saturate(dot(v.normal_w,lightDirection));
59.  
60.        if(lightIntensity > 0.0f)      
61.          returnColor += lightIntensity;        
62.  
63.        float3 diffuse = tex2D (_MainTex, v.uv).rgb;
64.        returnColor.rgb = atten*lightIntensity;      
65.  
66.        return saturate(returnColor);
67.      }
68.      
69.      ENDCG
70.    
71.    } // end pass "forward add"
72.    //-----------------------------
73.  

I get this behaviour
(center sphere is a reference with my working shader without tessellation)
What I expect: see the red light illuminate the plane and the 2nd sphere with attenuation and whatnot.