Help with SpeedTree shaders

Hello,

I wonder if anyone could help me make some changes to the shader code for SpeedTrees.

Currently the SpeedTrees really do not look good at all. In particular they show a greater contrast in the lighting than other objects in teh scene. It looks like the lighting is more strongly impacted by my single directional light than othe robjects.

Is the some way I can change the SpeedTree shader code to reduce the impact of th edirectional light and increase the influence of ambient light??????

I am not very knowledgeable about surface shaders but I can hack code.

Any help or tips are very welcome. The SpeedTree shader code can be found here

Thanks for any tips!!!!!!!


http://unity3d.com/download_unity/builtin_shaders.zip

Code (CSharp):

1. #ifndef SPEEDTREE_COMMON_INCLUDED
2. #define SPEEDTREE_COMMON_INCLUDED
3.  
4. #include "UnityCG.cginc"
5.  
6. #define SPEEDTREE_Y_UP
7.  
8. #if defined(GEOM_TYPE_BRANCH_DETAIL) || defined(GEOM_TYPE_BRANCH_BLEND)
9.     #define GEOM_TYPE_BRANCH
10. #endif
11.  
12. #include "SpeedTreeVertex.cginc"
13.  
14. // Define Input structure
15.  
16. struct Input
17. {
18.     fixed4 color;
19.     half3 interpolator1;
20.     #if defined(GEOM_TYPE_BRANCH_DETAIL) || defined(GEOM_TYPE_BRANCH_BLEND)
21.         half3 interpolator2;
22.     #endif
23.     #ifdef LOD_FADE_CROSSFADE
24.         half3 myScreenPos;
25.     #endif
26. };
27.    
28. // Define uniforms
29.  
30. #define mainTexUV interpolator1.xy
31. uniform sampler2D _MainTex;
32.  
33. #ifdef GEOM_TYPE_BRANCH_DETAIL
34.     #define Detail interpolator2.xy
35.     uniform sampler2D _DetailTex;
36. #endif
37.  
38. #ifdef GEOM_TYPE_BRANCH_BLEND
39.     #define BranchBlend interpolator2
40. #endif
41.  
42. #if defined(GEOM_TYPE_FROND) || defined(GEOM_TYPE_LEAF) || defined(GEOM_TYPE_FACING_LEAF)
43.     #define SPEEDTREE_ALPHATEST
44.     uniform fixed _Cutoff;
45. #endif
46.  
47. #ifdef EFFECT_HUE_VARIATION
48.     #define HueVariationAmount interpolator1.z
49.     uniform half4 _HueVariation;
50. #endif
51.  
52. #ifdef EFFECT_BUMP
53.     uniform sampler2D _BumpMap;
54. #endif
55.  
56. #ifdef LOD_FADE_CROSSFADE
57.     uniform sampler2D _DitherMaskLOD2D;
58. #endif
59.  
60. uniform fixed4 _Color;
61. uniform half _Shininess;
62.  
63. // Vertex processing
64.  
65. void SpeedTreeVert(inout SpeedTreeVB IN, out Input OUT)
66. {
67.     UNITY_INITIALIZE_OUTPUT(Input, OUT);
68.  
69.     OUT.mainTexUV = IN.texcoord.xy;
70.     OUT.color = _Color;
71.     OUT.color.rgb *= IN.color.r; // ambient occlusion factor
72.  
73.     #ifdef EFFECT_HUE_VARIATION
74.         float hueVariationAmount = frac(_Object2World[0].w + _Object2World[1].w + _Object2World[2].w);
75.         hueVariationAmount += frac(IN.vertex.x + IN.normal.y + IN.normal.x) * 0.5 - 0.3;
76.         OUT.HueVariationAmount = saturate(hueVariationAmount * _HueVariation.a);
77.     #endif
78.  
79.     #ifdef GEOM_TYPE_BRANCH_DETAIL
80.         OUT.Detail = IN.texcoord2.xy;
81.     #endif
82.  
83.     #ifdef GEOM_TYPE_BRANCH_BLEND
84.         OUT.BranchBlend = float3(IN.texcoord2.zw, IN.texcoord1.w);
85.     #endif
86.  
87.     OffsetSpeedTreeVertex(IN, unity_LODFade.x);
88.  
89.     #ifdef LOD_FADE_CROSSFADE
90.         float4 pos = mul(UNITY_MATRIX_MVP, IN.vertex);
91.         OUT.myScreenPos = ComputeScreenPos(pos).xyw;
92.         OUT.myScreenPos.xy *= _ScreenParams.xy * 0.25;
93.     #endif
94. }
95.  
96. // Fragment processing
97.  
98. #ifdef EFFECT_BUMP
99.     #define SPEEDTREE_DATA_NORMAL            fixed3 Normal;
100.     #define SPEEDTREE_COPY_NORMAL(to, from)    to.Normal = from.Normal;
101. #else
102.     #define SPEEDTREE_DATA_NORMAL
103.     #define SPEEDTREE_COPY_NORMAL(to, from)
104. #endif
105.  
106. #define SPEEDTREE_COPY_FRAG(to, from)    \
107.     to.Albedo = from.Albedo;            \
108.     to.Alpha = from.Alpha;                \
109.     to.Specular = from.Specular;        \
110.     to.Gloss = from.Gloss;                \
111.     SPEEDTREE_COPY_NORMAL(to, from)
112.  
113. struct SpeedTreeFragOut
114. {
115.     fixed3 Albedo;
116.     fixed Alpha;
117.     half Specular;
118.     fixed Gloss;
119.     SPEEDTREE_DATA_NORMAL
120. };
121.  
122. void SpeedTreeFrag(Input IN, out SpeedTreeFragOut OUT)
123. {
124.     #ifdef LOD_FADE_CROSSFADE
125.         half2 projUV = IN.myScreenPos.xy / IN.myScreenPos.z;
126.         projUV.y = frac(projUV.y) * 0.0625 /* 1/16 */ + unity_LODFade.y; // quantized lod fade by 16 levels
127.         clip(tex2D(_DitherMaskLOD2D, projUV).a - 0.5);
128.     #endif
129.  
130.     half4 diffuseColor = tex2D(_MainTex, IN.mainTexUV);
131.  
132.     OUT.Alpha = diffuseColor.a * _Color.a;
133.     #ifdef SPEEDTREE_ALPHATEST
134.         clip(OUT.Alpha - _Cutoff);
135.     #endif
136.  
137.     #ifdef GEOM_TYPE_BRANCH_DETAIL
138.         half4 detailColor = tex2D(_DetailTex, IN.Detail);
139.         diffuseColor.rgb = lerp(diffuseColor.rgb, detailColor.rgb, detailColor.a);
140.     #endif
141.  
142.     #ifdef GEOM_TYPE_BRANCH_BLEND
143.         half4 blendColor = tex2D(_MainTex, IN.BranchBlend.xy);
144.         half amount = saturate(IN.BranchBlend.z);
145.         diffuseColor.rgb = lerp(blendColor.rgb, diffuseColor.rgb, amount);
146.     #endif
147.  
148.     #ifdef EFFECT_HUE_VARIATION
149.         half3 shiftedColor = lerp(diffuseColor.rgb, _HueVariation.rgb, IN.HueVariationAmount);
150.         half maxBase = max(diffuseColor.r, max(diffuseColor.g, diffuseColor.b));
151.         half newMaxBase = max(shiftedColor.r, max(shiftedColor.g, shiftedColor.b));
152.         maxBase /= newMaxBase;
153.         maxBase = maxBase * 0.5f + 0.5f;
154.         // preserve vibrance
155.         shiftedColor.rgb *= maxBase;
156.         diffuseColor.rgb = saturate(shiftedColor);
157.     #endif
158.  
159.     OUT.Albedo = diffuseColor.rgb * IN.color.rgb;
160.     OUT.Gloss = diffuseColor.a;
161.     OUT.Specular = _Shininess;
162.  
163.     #ifdef EFFECT_BUMP
164.         OUT.Normal = UnpackNormal(tex2D(_BumpMap, IN.mainTexUV));
165.     #endif
166. }
167.  
168. #endif // SPEEDTREE_COMMON_INCLUDED

 

I agree about there being too much contrast between light and shadow on the speed trees. Decreasing the bias on the scene's directional light helped a bit. Best of luck.

Also if anyone has seen documentation on the speedtree and speedtree billboard shader I'd love a link.

 

Here's a link to our documentation, hope it helps!

http://docs.speedtree.com/doku.php