Fix normals for normal object.

data/shaders/instanced_grass.vert

@@ -13,42 +13,8 @@ in vec4 Color;
 out vec3 nor;
 out vec2 uv;
 
-mat4 getMatrixFromRotation(vec3 rotation)
+mat4 getWorldMatrix(vec3 translation, vec3 rotation);
-{
+mat4 getInverseWorldMatrix(vec3 translation, vec3 rotation);
-
-    // from irrlicht
-    float cr = cos( rotation.z );
-    float sr = sin( rotation.z );
-    float cp = cos( rotation.x );
-    float sp = sin( rotation.x );
-    float cy = cos( rotation.y );
-    float sy = sin( rotation.y );
-
-    float srsp = sr*sp;
-    float crsp = cr*sp;
-
-    return mat4(
-        vec4(cp * cy, srsp * cy - cr * sy, crsp * cy + sr * sy, 0.),
-        vec4(cp * sy, srsp * sy + cr * cy, crsp * sy - sr * cy, 0.),
-        vec4(-sp, sr * cp, cr * cp, 0.),
-        vec4(0., 0., 0., 1.));
-}
-
-mat4 getWorldMatrix(vec3 translation, vec3 rotation)
-{
-    mat4 result = getMatrixFromRotation(rotation);
-    // translation
-    result[3].xyz += translation;
-    return result;
-}
-
-mat4 getInverseWorldMatrix(vec3 translation, vec3 rotation)
-{
-    mat4 result = transpose(getMatrixFromRotation(rotation));
-    // FIXME: it's wrong but the fourth column is not used
-    result[3].xyz -= translation;
-    return result;
-}
 
 void main()
 {

data/shaders/instanced_object_pass.vert

@@ -1,5 +1,5 @@
 uniform mat4 ViewProjectionMatrix;
-uniform mat4 ViewMatrix;
+uniform mat4 InverseViewMatrix;
 
 in vec3 Origin;
 in vec3 Orientation;
@@ -11,11 +11,13 @@ in vec2 Texcoord;
 out vec3 nor;
 out vec2 uv;
 
+mat4 getWorldMatrix(vec3 translation, vec3 rotation);
+mat4 getInverseWorldMatrix(vec3 translation, vec3 rotation);
+
 void main(void)
 {
-    mat4 ModelMatrix = mat4(1.);
+    mat4 ModelMatrix = getWorldMatrix(Origin, Orientation);
-    ModelMatrix[3].xyz += Origin;
+    mat4 TransposeInverseModelView = transpose(getInverseWorldMatrix(Origin, Orientation) * InverseViewMatrix);
-    mat4 TransposeInverseModelView = transpose(inverse(ViewMatrix * ModelMatrix));
     gl_Position = ViewProjectionMatrix *  ModelMatrix * vec4(Position, 1.);
     nor = (TransposeInverseModelView * vec4(Normal, 0.)).xyz;
     uv = Texcoord;

data/shaders/utils/getworldmatrix.vert

@@ -0,0 +1,36 @@
+mat4 getMatrixFromRotation(vec3 rotation)
+{
+
+    // from irrlicht
+    float cr = cos( rotation.z );
+    float sr = sin( rotation.z );
+    float cp = cos( rotation.x );
+    float sp = sin( rotation.x );
+    float cy = cos( rotation.y );
+    float sy = sin( rotation.y );
+
+    float srsp = sr*sp;
+    float crsp = cr*sp;
+
+    return mat4(
+        vec4(cp * cy, srsp * cy - cr * sy, crsp * cy + sr * sy, 0.),
+        vec4(cp * sy, srsp * sy + cr * cy, crsp * sy - sr * cy, 0.),
+        vec4(-sp, sr * cp, cr * cp, 0.),
+        vec4(0., 0., 0., 1.));
+}
+
+mat4 getWorldMatrix(vec3 translation, vec3 rotation)
+{
+    mat4 result = getMatrixFromRotation(rotation);
+    // translation
+    result[3].xyz += translation;
+    return result;
+}
+
+mat4 getInverseWorldMatrix(vec3 translation, vec3 rotation)
+{
+    mat4 result = transpose(getMatrixFromRotation(rotation));
+    // FIXME: it's wrong but the fourth column is not used
+    result[3].xyz -= translation;
+    return result;
+}

src/graphics/shaders.cpp

@@ -514,6 +514,7 @@ namespace MeshShader
     void InstancedObjectPass1Shader::init()
     {
         Program = LoadProgram(
+            GL_VERTEX_SHADER, file_manager->getAsset("shaders/utils/getworldmatrix.vert").c_str(),
             GL_VERTEX_SHADER, file_manager->getAsset("shaders/instanced_object_pass.vert").c_str(),
             GL_FRAGMENT_SHADER, file_manager->getAsset("shaders/utils/encode_normal.frag").c_str(),
             GL_FRAGMENT_SHADER, file_manager->getAsset("shaders/object_pass1.frag").c_str());
@@ -521,7 +522,7 @@ namespace MeshShader
         attrib_position = glGetAttribLocation(Program, "Position");
         attrib_normal = glGetAttribLocation(Program, "Normal");
         uniform_MP = glGetUniformLocation(Program, "ViewProjectionMatrix");
-        uniform_VM = glGetUniformLocation(Program, "ViewMatrix");
+        uniform_VM = glGetUniformLocation(Program, "InverseViewMatrix");
     }
 
     void InstancedObjectPass1Shader::setUniforms(const core::matrix4 &ModelViewProjectionMatrix, const core::matrix4 &ViewMatrix)
@@ -545,6 +546,7 @@ namespace MeshShader
     void InstancedGrassPass1Shader::init()
     {
         Program = LoadProgram(
+            GL_VERTEX_SHADER, file_manager->getAsset("shaders/utils/getworldmatrix.vert").c_str(),
             GL_VERTEX_SHADER, file_manager->getAsset("shaders/instanced_grass.vert").c_str(),
             GL_FRAGMENT_SHADER, file_manager->getAsset("shaders/utils/encode_normal.frag").c_str(),
             GL_FRAGMENT_SHADER, file_manager->getAsset("shaders/objectref_pass1.frag").c_str());
@@ -627,6 +629,7 @@ namespace MeshShader
     void InstancedObjectPass2Shader::init()
     {
         Program = LoadProgram(
+            GL_VERTEX_SHADER, file_manager->getAsset("shaders/utils/getworldmatrix.vert").c_str(),
             GL_VERTEX_SHADER, file_manager->getAsset("shaders/instanced_object_pass.vert").c_str(),
             GL_FRAGMENT_SHADER, file_manager->getAsset("shaders/utils/getLightFactor.frag").c_str(),
             GL_FRAGMENT_SHADER, file_manager->getAsset("shaders/object_pass2.frag").c_str());
@@ -926,6 +929,7 @@ namespace MeshShader
     void InstancedGrassPass2Shader::init()
     {
         Program = LoadProgram(
+            GL_VERTEX_SHADER, file_manager->getAsset("shaders/utils/getworldmatrix.vert").c_str(),
             GL_VERTEX_SHADER, file_manager->getAsset("shaders/instanced_grass.vert").c_str(),
             GL_FRAGMENT_SHADER, file_manager->getAsset("shaders/utils/getLightFactor.frag").c_str(),
             GL_FRAGMENT_SHADER, file_manager->getAsset("shaders/objectref_pass2.frag").c_str());