Allow explicit segment count limitation

inkscape_raytracing/raytracing/world.py

@@ -19,14 +19,18 @@ class OpticalObject(NamedTuple):
     material: OpticMaterial
 
 
+class Tip(NamedTuple):
+    beam: Ray
+    rays: List
+
+
 @dataclass
 class World:
     """Stores a scene and computes the interaction with a ray"""
 
     objects: Optional[list[OpticalObject]] = field(default_factory=list)
-    # default recursion depth can be changed, but should not exceed
-    # system recursion limit.
-    max_recursion_depth: Optional[int] = 500
+    max_segment_count: Optional[int] = 500
+    show_warning: Optional[bool] = True
 
     def add(self, obj: OpticalObject):
         self.objects.append(obj)
@@ -56,38 +60,29 @@ def first_hit(self, ray: Ray) -> Tuple[ShadeRec, OpticMaterial]:
         return result, material
 
     def propagate_beams(self, seed):
-        return self._propagate_beams([[seed]], 0)
-
-    def _propagate_beams(self, beams: List[List[Ray]], depth) -> List[List[Ray]]:
-        """Computes the propagation of beams in the system
-
-        :return: List of all the beam paths generated by these seeds.
-            It is stored as
-            [path0[Ray0, Ray1, ...], path1[...], ...].
-            Each path is a list of successive rays having each traveled a
-            given distance.
-        :raise: warning if recursion depth hits a limit.
-        """
-
-        if depth >= self.max_recursion_depth:
-            err_msg = (
-                f"Maximal recursion depth exceeded ({self.max_recursion_depth})."
-                "It is  likely that not all beams have been rendered."
-            )
-            warnings.warn(err_msg)
-            return beams
-        else:
-            new_beams = list()
-            for index, beam in enumerate(beams):
-                ray = beam[-1]
-                if ray.travel <= 0:
-                    shade, material = self.first_hit(ray)
-                    new_seeds = material.generated_beams(ray, shade)
-                    beams[index][-1] = Ray(ray.origin, ray.direction, shade.travel_dist)
-                    if len(new_seeds) == 0:
-                        new_beams.append(beams[index])
-                    for seed in new_seeds:
-                        generated_beams = self._propagate_beams([[seed]], depth + 1)
-                        for new_beam in generated_beams:
-                            new_beams.append(beams[index] + new_beam)
-            return new_beams
+        initial_beam = []
+        beams = [initial_beam]
+        tips = [Tip(seed, initial_beam)]
+        while len(tips):
+            tip = tips.pop(0)
+            if len(tip.rays) >= self.max_segment_count:
+                err_msg = (
+                    f"Maximal segment count exceeded ({self.max_segment_count})."
+                    "It is likely that not all beams have been rendered."
+                )
+                tips = []
+                if self.show_warning:
+                    warnings.warn(err_msg)
+            else:
+                shade, material = self.first_hit(tip.beam)
+                new_seeds = material.generated_beams(tip.beam, shade)
+                ray = Ray(tip.beam.origin, tip.beam.direction, shade.travel_dist)
+                tip.rays.append(ray)
+                rays = [tip.rays] if len(new_seeds) == 1 else [tip.rays, *[[*tip.rays] for i in range(len(new_seeds)-1)]]
+                for index, seed in enumerate(new_seeds):
+                    tips.append(Tip(seed, rays[index]))
+                rays.pop(0)
+                for r in rays:
+                    beams.append(r)
+
+        return beams

inkscape_raytracing/render.inx

@@ -11,5 +11,7 @@
     <script>
         <command location="inx" interpreter="python">render.py</command>
     </script>
+    <param name="max_segment_count" type="int" gui-text="Maximum segment count:" max="10000" indent="1">500</param>
+    <param name="show_iteration_warning" type="bool" gui-text="Display iteration limit reached warning">true</param>
 </inkscape-extension>
 

inkscape_raytracing/render.py

@@ -75,10 +75,16 @@ def __init__(self):
         self.world = World()
         self.beam_seeds: list[BeamSeed] = list()
 
+    def add_arguments(self, pars):
+        pars.add_argument("--max_segment_count", type=int)
+        pars.add_argument("--show_iteration_warning", type=str)
+
     def effect(self) -> None:
         """
         Loads the objects and outputs a svg with the beams after propagation
         """
+        self.world.max_segment_count = self.options.max_segment_count
+        self.world.show_warning = self.options.show_iteration_warning == 'true'
 
         # Can't set the border earlier because self.svg is not yet defined
         self.document_border = self.get_document_borders_as_beamdump()

pyproject.toml

@@ -1,6 +1,6 @@
 [tool.poetry]
 name = "inkscape-raytracing"
-version = "1.1"
+version = "1.2.0"
 description = "An extension for Inkscape that makes it easier to draw optical diagrams."
 authors = ["Your Name <[email protected]>"]
 license = "GPL3"