Fix inconsistency between grass shader and the instanced version

1. Assign the missing depth stencil texture (dtex)

2. Correct the movement and color

data/shaders/grass_pass.vert

@@ -19,9 +19,18 @@ out vec2 uv;
 
 void main()
 {
+
+    mat4 new_model_matrix = ModelMatrix;
+    mat4 new_inverse_model_matrix = InverseModelMatrix;
+    new_model_matrix[3].xyz += windDir * Color.r;
+
+    // FIXME doesn't seem to make too much difference in pass 2, because this
+    // affects "nor" which is later only * 0.1 by scattering
+    new_inverse_model_matrix[3].xyz -= windDir * Color.r;
+
+    mat4 ModelViewProjectionMatrix = ProjectionMatrix * ViewMatrix * new_model_matrix;
+    mat4 TransposeInverseModelView = transpose(InverseViewMatrix * new_inverse_model_matrix);
+    gl_Position = ModelViewProjectionMatrix * vec4(Position, 1.);
+    nor = (TransposeInverseModelView * vec4(Normal, 0.)).xyz;
     uv = Texcoord;
-    mat4 ModelViewProjectionMatrix = ProjectionMatrix * ViewMatrix * ModelMatrix;
-    mat4 TransposeInverseModelView = transpose(InverseModelMatrix * InverseViewMatrix);
-    nor = (TransposeInverseModelView * vec4(Normal, 1.)).xyz;
-    gl_Position = ModelViewProjectionMatrix * vec4(Position + windDir * Color.r, 1.);
 }

data/shaders/grass_pass2.frag

@@ -39,8 +39,8 @@ void main(void)
 
     float fLdotNBack  = max(0., - dot(nor, L) * 0.6 + 0.4);
     float scattering = mix(fPowEdotL, fLdotNBack, .5);
-    float specmap = texture(SpecMap, uv).g;
 
-    vec3 LightFactor = color.xyz * (scattering * 0.3) + getLightFactor(color.xyz, vec3(1.), specmap, 0.);
-    FragColor = vec4(color.xyz * LightFactor, 1.);
+    float specmap = texture(SpecMap, uv).g;
+    vec3 LightFactor = color.xyz * (scattering * 0.1) + getLightFactor(color.xyz, vec3(1.), specmap, 0.);
+    FragColor = vec4(LightFactor, 1.);
 }

src/graphics/draw_policies.cpp

@@ -86,7 +86,48 @@ void renderMeshes2ndPass( const std::vector<uint64_t> &Prefilled_Handle,
     }
 }   // renderMeshes2ndPass
 
+// ----------------------------------------------------------------------------
+template<>
+void renderMeshes2ndPass<GrassMat, 3, 1>
+    (const std::vector<uint64_t> &Prefilled_Handle,
+     const std::vector<GLuint> &Prefilled_Tex)
+{
+    auto &meshes = GrassMat::List::getInstance()->SolidPass;
+    GrassMat::SecondPassShader::getInstance()->use();
+    if (CVS->isARBBaseInstanceUsable())
+        glBindVertexArray(VAOManager::getInstance()->getVAO(GrassMat::VertexType));
+    for (unsigned i = 0; i < meshes.size(); i++)
+    {
+        GLMesh &mesh = *(STK::tuple_get<0>(meshes.at(i)));
+        if (!CVS->isARBBaseInstanceUsable())
+            glBindVertexArray(mesh.vao);
 
+        if (mesh.VAOType != GrassMat::VertexType)
+        {
+#ifdef DEBUG
+            Log::error("Materials", "Wrong vertex Type associed to pass 2 "
+                                    "(hint texture : %s)",
+                       mesh.textures[0]->getName().getPath().c_str());
+#endif
+            continue;
+        }
+
+        if (CVS->isAZDOEnabled())
+        {
+            HandleExpander<GrassMat::SecondPassShader>::
+                expand(mesh.TextureHandles, GrassMat::SecondPassTextures,
+                       Prefilled_Handle[0], Prefilled_Handle[1],
+                       Prefilled_Handle[2], Prefilled_Handle[3]);
+        }
+        else
+        {
+            TexExpander<GrassMat::SecondPassShader>::
+                expandTex(mesh, GrassMat::SecondPassTextures, Prefilled_Tex[0],
+                          Prefilled_Tex[1], Prefilled_Tex[2], Prefilled_Tex[3]);
+        }
+        CustomUnrollArgs<3, 1>::template drawMesh<GrassMat::SecondPassShader>(meshes.at(i));
+    }
+}   // renderMeshes2ndPass
 
 // ----------------------------------------------------------------------------
 template<typename T, int...List>

src/graphics/materials.hpp

@@ -536,7 +536,7 @@ public:
 
 
 // ============================================================================
-class GrassPass2Shader : public TextureShader<GrassPass2Shader, 5, core::matrix4,
+class GrassPass2Shader : public TextureShader<GrassPass2Shader, 6, core::matrix4,
                                        core::vector3df>
 {
 public:
@@ -548,6 +548,7 @@ public:
         assignSamplerNames(0, "DiffuseMap", ST_NEAREST_FILTERED,
                            1, "SpecularMap", ST_NEAREST_FILTERED,
                            2, "SSAO", ST_BILINEAR_FILTERED,
+                           3, "dtex", ST_NEAREST_FILTERED,
                            3, "Albedo", ST_TRILINEAR_ANISOTROPIC_FILTERED,
                            4, "SpecMap", ST_TRILINEAR_ANISOTROPIC_FILTERED);
     }   // GrassPass2Shader