Further tweak frustum culling to be more efficient

[libs/gl.git] / source / scene.cpp

diff --git a/source/scene.cpp b/source/scene.cpp
index 7896d23d6246830d0f1716beaf830a0cff4e8665..7d3c167975e7a3c548de29cc5aff782439e46a3a 100644 (file)
--- a/source/scene.cpp
+++ b/source/scene.cpp
@@ -21,42 +21,48 @@ void Scene::render(const Tag &tag) const
        render(renderer, tag);
 }
 
-void Scene::setup_frustum(const Renderer &renderer) const
+bool Scene::setup_frustum(const Renderer &renderer) const
 {
        const Camera *camera = renderer.get_camera();
        if(!camera)
-               return;
+               return false;
+
+       const Matrix &matrix = camera->get_object_matrix();
 
        float y = tan(camera->get_field_of_view()/2.0f);
        float s = sqrt(y*y+1);
-       frustum_edges[0] = Vector3(0, 1/s, y/s);
-       frustum_edges[1] = Vector3(0, -1/s, y/s);
+       frustum_edges[0] = matrix*Vector4(0, 1/s, y/s, 0);
+       frustum_edges[1] = matrix*Vector4(0, -1/s, y/s, 0);
 
        float x = y*camera->get_aspect();
        s = sqrt(x*x+1);
-       frustum_edges[2] = Vector3(1/s, 0, x/s);
-       frustum_edges[3] = Vector3(-1/s, 0, x/s);
+       frustum_edges[2] = matrix*Vector4(1/s, 0, x/s, 0);
+       frustum_edges[3] = matrix*Vector4(-1/s, 0, x/s, 0);
+
+       const Vector3 &camera_pos = camera->get_position();
+       Vector4 pos4 = compose(camera_pos, 0.0f);
+       for(unsigned i=0; i<4; ++i)
+               frustum_edges[i].w = -inner_product(frustum_edges[i], pos4);
+
+       const Vector3 &look_dir = camera->get_look_direction();
+       frustum_edges[4] = compose(look_dir, -dot(camera_pos, look_dir)-camera->get_far_clip());
+       frustum_edges[5] = compose(-look_dir, dot(camera_pos, look_dir)+camera->get_near_clip());
+
+       return true;
 }
 
-bool Scene::frustum_cull(const Renderer &renderer, const Renderable &renderable) const
+bool Scene::frustum_cull(const Renderable &renderable) const
 {
        const Matrix *matrix = renderable.get_matrix();
        const Geometry::BoundingSphere<float, 3> *bsphere = renderable.get_bounding_sphere();
-       const Camera *camera = renderer.get_camera();
-       if(!matrix || !bsphere || !camera)
+       if(!matrix || !bsphere)
                return false;
 
-       Matrix mvm = camera->get_matrix()**matrix;
-       float n = camera->get_near_clip();
-       float f = camera->get_far_clip();
-
-       Vector3 center = mvm*bsphere->get_center();
+       Vector4 center = *matrix*compose(bsphere->get_center(), 1.0f);
        float radius = bsphere->get_radius();
 
-       if(center.z-radius>-n || center.z+radius<-f)
-               return true;
-       for(unsigned i=0; i<4; ++i)
-               if(dot(center, frustum_edges[i])>radius)
+       for(unsigned i=0; i<6; ++i)
+               if(inner_product(center, frustum_edges[i])>radius)
                        return true;
 
        return false;