Move frustum culling from Scene to Camera

[libs/gl.git] / source / render / camera.cpp

diff --git a/source/render/camera.cpp b/source/render/camera.cpp
index 3ace92b9ecb7166de54fa20b33f07c943997dae1..7ffe0c155e60f6a6b968869901485a2c399fd7e6 100644 (file)
--- a/source/render/camera.cpp
+++ b/source/render/camera.cpp
@@ -125,6 +125,27 @@ Vector3 Camera::unproject(const Vector3 &p) const
        return unproject(Vector4(p.x, p.y, p.z, 1.0f)).slice<3>(0);
 }
 
+bool Camera::is_in_frustum(const Renderable &renderable) const
+{
+       const Matrix *rmatrix = renderable.get_matrix();
+       const Geometry::BoundingSphere<float, 3> *bsphere = renderable.get_bounding_sphere();
+       if(!rmatrix || !bsphere)
+               return true;
+
+       Vector4 center = *rmatrix*compose(bsphere->get_center(), 1.0f);
+       Vector3 x_axis = (rmatrix->column(0)*bsphere->get_radius()).slice<3>(0);
+       float radius_sq = inner_product(x_axis, x_axis);
+
+       for(unsigned i=0; i<6; ++i)
+       {
+               float distance = inner_product(center, frustum_planes[i]);
+               if(distance<0 && distance*distance>radius_sq)
+                       return false;
+       }
+
+       return true;
+}
+
 void Camera::update_projection_matrix()
 {
        float frustum_h = (fov!=Geometry::Angle<float>::zero() ? tan(fov/2.0f)*clip_near : height/2);
@@ -141,6 +162,8 @@ void Camera::update_projection_matrix()
 
        shdata.uniform("clip_eye_matrix", proj_matrix);
        shdata.uniform("eye_clip_matrix", invert(proj_matrix));
+
+       update_frustum_planes();
 }
 
 void Camera::update_object_matrix()
@@ -156,6 +179,43 @@ void Camera::update_object_matrix()
 
        shdata.uniform("world_eye_matrix", matrix);
        shdata.uniform("eye_world_matrix", view_matrix);
+
+       update_frustum_planes();
+}
+
+void Camera::update_frustum_planes()
+{
+       // TODO Handle off-center and rotated frustums
+       if(is_orthographic())
+       {
+               frustum_planes[0] = Vector4(0, 1, 0, height);
+               frustum_planes[1] = Vector4(0, -1, 0, height);
+
+               frustum_planes[2] = Vector4(1, 0, 0, height*aspect);
+               frustum_planes[3] = Vector4(-1, 0, 0, height*aspect);
+       }
+       else
+       {
+               float y = tan(fov/2.0f);
+               float s = sqrt(y*y+1);
+               frustum_planes[0] = Vector4(0, 1/s, -y/s, 0);
+               frustum_planes[1] = Vector4(0, -1/s, -y/s, 0);
+
+               float x = y*aspect;
+               s = sqrt(x*x+1);
+               frustum_planes[2] = Vector4(1/s, 0, -x/s, 0);
+               frustum_planes[3] = Vector4(-1/s, 0, -x/s, 0);
+       }
+
+       frustum_planes[4] = Vector4(0, 0, 1, clip_far);
+       frustum_planes[5] = Vector4(0, 0, -1, -clip_near);
+
+       for(unsigned i=0; i<6; ++i)
+       {
+               Vector3 normal = frustum_planes[i].slice<3>(0);
+               normal = (matrix*compose(normal, 0.0f)).slice<3>(0);
+               frustum_planes[i] = compose(normal, frustum_planes[i].w-dot(normal, matrix.column(3).slice<3>(0)));
+       }
 }
 
 void Camera::set_debug_name(const string &name)