arbitrary beam tracing

1 files changed, 31 insertions, 0 deletions

diff --git a/beam_trace.m b/beam_trace.m
new file mode 100644
index 0000000..401391a
--- /dev/null
+++ b/beam_trace.m
@@ -0,0 +1,31 @@
+function ret = beam_trace(beams, faces, borders)
+	%% trace beam and all it reflections and refractions on faces
+	% for beams and faces structure description see face_beam_interaction.m
+	% border similar to faces cell array which enclose the beam
+	% i.e. it does not leave the polygon consisting of border faces
+
+	Nbeams=size(beams)(2);
+	if ( Nbeams == 0 )
+		% no more beam to trace
+		return;
+	end
+
+	% trace each beam in beams cell array
+	for i=1:Nbeams
+		beam=beams{i};
+		[is_face_hit, hit_position, hit_distance, new_beams] =  face_beam_interaction(beam, faces);
+		if (is_face_hit)
+			beam_trace(new_beams, faces, borders );
+			continue;
+		end
+
+		% beam does not hit face but it should stop and borders
+		beam.face=NA;
+		[is_face_hit, hit_position, hit_distance, new_beams] =  face_beam_interaction(beam, borders);
+		if (!is_face_hit)
+			error('borders are badly defined, the beam misses them');
+		end
+	end
+end
+
+