From 9a1e103a7f32031e528a7f9f82b1e64c5c12f59c Mon Sep 17 00:00:00 2001
From: Grant Sanderson <grant@3blue1brown.com>
Date: Fri, 8 Jan 2021 22:26:47 -0800
Subject: [PATCH] Introduce flat_stroke uniform

---
 manimlib/mobject/three_dimensions.py         |  1 +
 manimlib/mobject/types/vectorized_mobject.py | 13 +++++++++++++
 2 files changed, 14 insertions(+)

diff --git a/manimlib/mobject/three_dimensions.py b/manimlib/mobject/three_dimensions.py
index 2918a6ac..1949aca9 100644
--- a/manimlib/mobject/three_dimensions.py
+++ b/manimlib/mobject/three_dimensions.py
@@ -16,6 +16,7 @@ class SurfaceMesh(VGroup):
         "stroke_width": 1,
         "normal_nudge": 1e-2,
         "depth_test": True,
+        "flat_stroke": False,
     }
 
     def __init__(self, uv_surface, **kwargs):
diff --git a/manimlib/mobject/types/vectorized_mobject.py b/manimlib/mobject/types/vectorized_mobject.py
index 5d5c59c4..4a9ca676 100644
--- a/manimlib/mobject/types/vectorized_mobject.py
+++ b/manimlib/mobject/types/vectorized_mobject.py
@@ -62,6 +62,7 @@ class VMobject(Mobject):
         # "fill_frag_shader_file": "quadratic_bezier_fill_frag.glsl",
         # Could also be Bevel, Miter, Round
         "joint_type": "auto",
+        "flat_stroke": True,
         "render_primitive": moderngl.TRIANGLES,
         "triangulation_locked": False,
         "fill_dtype": [
@@ -106,6 +107,7 @@ class VMobject(Mobject):
             background=self.draw_stroke_behind_fill,
         )
         self.set_gloss(self.gloss)
+        self.set_flat_stroke(self.flat_stroke)
         return self
 
     def generate_rgba_array(self, color, opacity):
@@ -336,6 +338,16 @@ class VMobject(Mobject):
             return self.get_fill_opacity()
         return self.get_stroke_opacity()
 
+    def set_flat_stroke(self, flat_stroke=True, family=True):
+        self.flat_stroke = flat_stroke
+        if family:
+            for submob in self.submobjects:
+                submob.set_flat_stroke(flat_stroke, family)
+        return self
+
+    def get_flat_stroke(self):
+        return self.flat_stroke
+
     # TODO, this currently does nothing
     def color_using_background_image(self, background_image_file):
         self.background_image_file = background_image_file
@@ -970,6 +982,7 @@ class VMobject(Mobject):
         }
         result = super().get_shader_uniforms()
         result["joint_type"] = j_map[self.joint_type]
+        result["flat_stroke"] = float(self.flat_stroke)
         return result
 
     def get_stroke_shader_data(self):