Translate code, comments and logs to English; English README; configurable paths and env varsHEADmain

Identifiers, docstrings, comments and console messages are now in English.
Narration, subtitles and on-screen text stay in Spanish (they are the video
content). The Blender <-> Godot physics protocol uses English keys and body
prefixes chosen to keep the original creation order, so cached simulations and
renders stay bit-identical. The old Spanish environment variable names are still
accepted.

1 files changed, 59 insertions, 59 deletions

diff --git a/scenes/v13_cuerda.py b/scenes/v13_cuerda.py
index 5ca224d..c02ea1c 100644
--- a/scenes/v13_cuerda.py
+++ b/scenes/v13_cuerda.py
@@ -4,13 +4,13 @@ sys.path.insert(0, os.path.dirname(os.path.abspath(__file__)))
 from manim import *
 from tiktok import *
 
-CEN = UP * 1.75
-RT = 2.05           # radio de la Tierra en pantalla
-HUECO = 0.72        # separacion dibujada (exagerada)
+CTR = UP * 1.75
+RT = 2.05           # Earth radius on screen
+GAP_W = 0.72        # drawn gap (exaggerated)
 
 
-def gato(h=0.55, color="#E8EDF7"):
-    """Silueta simple de gato de perfil, alto total = h."""
+def cat(h=0.55, color="#E8EDF7"):
+    """Simple cat silhouette in profile, total height = h."""
     body = Ellipse(width=0.90, height=0.34, stroke_width=0, fill_color=color,
                    fill_opacity=1).move_to([0, 0.12, 0])
     head = Circle(radius=0.17, stroke_width=0, fill_color=color,
@@ -27,29 +27,29 @@ def gato(h=0.55, color="#E8EDF7"):
     return g
 
 
-class Cuerda(TikTok):
+class Rope(TikTok):
     NAME = "cuerda"
 
-    def planeta(self, r, center, col="#1D3B6E"):
-        p = Circle(radius=r, stroke_width=4, stroke_color=CELESTE,
+    def planet(self, r, center, col="#1D3B6E"):
+        p = Circle(radius=r, stroke_width=4, stroke_color=C_SKY,
                    fill_color=col, fill_opacity=1).move_to(center)
         return p
 
     def construct(self):
         self.prepare()
-        chip = self.chip("Intuición rota", CELESTE)
+        chip = self.chip("Intuición rota", C_SKY)
 
-        tierra = self.planeta(RT, CEN)
-        cuerda = Circle(radius=RT + 0.03, stroke_width=7, color=AMBAR).move_to(CEN)
+        earth = self.planet(RT, CTR)
+        rope = Circle(radius=RT + 0.03, stroke_width=7, color=AMBER).move_to(CTR)
 
         with self.beat(0) as b:
             b.play(FadeIn(chip, shift=DOWN * 0.3), run_time=0.45)
-            b.play(GrowFromCenter(tierra), run_time=0.7)
-            b.play(Create(cuerda), run_time=max(0.8, b.floor - 1.6))
+            b.play(GrowFromCenter(earth), run_time=0.7)
+            b.play(Create(rope), run_time=max(0.8, b.floor - 1.6))
 
         with self.beat(1) as b:
-            km = Text("40.000 km", font=FONT, font_size=50, weight=BOLD, color=AMBAR)
-            km.move_to(CEN + DOWN * 0.0)
+            km = Text("40.000 km", font=FONT, font_size=50, weight=BOLD, color=AMBER)
+            km.move_to(CTR + DOWN * 0.0)
             box = RoundedRectangle(corner_radius=0.16, stroke_width=0, fill_color="#0B0F1A",
                                    fill_opacity=0.78, width=km.width + 0.5,
                                    height=km.height + 0.35).move_to(km)
@@ -57,37 +57,37 @@ class Cuerda(TikTok):
 
         with self.beat(2) as b:
             b.play(FadeOut(VGroup(box, km)), run_time=0.3)
-            seg = Line(LEFT * 0.6, RIGHT * 0.6, stroke_width=9, color=VERDE)
-            tip = VGroup(*[Line(UP * 0.16, DOWN * 0.16, stroke_width=6, color=VERDE)
-                           .move_to(p) for p in (seg.get_start(), seg.get_end())])
-            lab = Text("+ 1 metro", font=FONT, font_size=48, weight=BOLD, color=VERDE)
-            g = VGroup(VGroup(seg, tip), lab).arrange(DOWN, buff=0.3).move_to(DOWN * 2.15)
-            b.play(GrowFromCenter(VGroup(seg, tip)), run_time=0.5)
+            seg_m = Line(LEFT * 0.6, RIGHT * 0.6, stroke_width=9, color=C_GREEN)
+            tip = VGroup(*[Line(UP * 0.16, DOWN * 0.16, stroke_width=6, color=C_GREEN)
+                           .move_to(p) for p in (seg_m.get_start(), seg_m.get_end())])
+            lab = Text("+ 1 metro", font=FONT, font_size=48, weight=BOLD, color=C_GREEN)
+            g = VGroup(VGroup(seg_m, tip), lab).arrange(DOWN, buff=0.3).move_to(DOWN * 2.15)
+            b.play(GrowFromCenter(VGroup(seg_m, tip)), run_time=0.5)
             b.play(FadeIn(lab, shift=UP * 0.15), run_time=0.6)
 
         with self.beat(3) as b:
-            alta = Circle(radius=RT + HUECO, stroke_width=7, color=AMBAR).move_to(CEN)
+            high_c = Circle(radius=RT + GAP_W, stroke_width=7, color=AMBER).move_to(CTR)
             radios = VGroup(*[
-                DashedLine(CEN + RT * np.array([math.cos(a), math.sin(a), 0]),
-                           CEN + (RT + HUECO) * np.array([math.cos(a), math.sin(a), 0]),
+                DashedLine(CTR + RT * np.array([math.cos(a), math.sin(a), 0]),
+                           CTR + (RT + GAP_W) * np.array([math.cos(a), math.sin(a), 0]),
                            stroke_width=4, color="#7C8AA8", dash_length=0.07)
                 for a in np.linspace(0, TAU, 16, endpoint=False)])
             b.play(FadeOut(g), run_time=0.25)
-            b.play(Transform(cuerda, alta), run_time=1.0)
+            b.play(Transform(rope, high_c), run_time=1.0)
             b.play(FadeIn(radios), run_time=0.5)
-            esc = Text("(dibujo exagerado)", font=FONT, font_size=28, color=GRIS)
-            esc.move_to(DOWN * 2.6)
-            b.play(FadeIn(esc), run_time=0.35)
+            scale_f = Text("(dibujo exagerado)", font=FONT, font_size=28, color=C_GRAY)
+            scale_f.move_to(DOWN * 2.6)
+            b.play(FadeIn(scale_f), run_time=0.35)
 
         with self.beat(4) as b:
             q = VGroup(
                 self.fit(Text("¿cuánto se separa?", font=FONT, font_size=52,
                               weight=BOLD, color=WHITE), 8.0),
                 VGroup(
-                    Text("«nada»", font=FONT, font_size=40, color=GRIS),
-                    Text("«un pelo»", font=FONT, font_size=40, color=GRIS),
+                    Text("«nada»", font=FONT, font_size=40, color=C_GRAY),
+                    Text("«un pelo»", font=FONT, font_size=40, color=C_GRAY),
                 ).arrange(RIGHT, buff=0.7),
-            ).arrange(DOWN, buff=0.35).move_to(CEN)
+            ).arrange(DOWN, buff=0.35).move_to(CTR)
             bx = RoundedRectangle(corner_radius=0.2, stroke_width=0, fill_color="#0B0F1A",
                                   fill_opacity=0.82, width=q.width + 0.6,
                                   height=q.height + 0.5).move_to(q)
@@ -95,67 +95,67 @@ class Cuerda(TikTok):
 
         with self.beat(5) as b:
             b.play(FadeOut(VGroup(bx, q)), run_time=0.3)
-            gt = gato(HUECO * 0.92).move_to(CEN + UP * (RT + HUECO / 2))
-            med = DoubleArrow(CEN + LEFT * RT, CEN + LEFT * (RT + HUECO), buff=0,
-                              color=VERDE, stroke_width=6, tip_length=0.18)
-            val = Text("15,9 cm", font=FONT, font_size=42, weight=BOLD, color=VERDE)
+            gt = cat(GAP_W * 0.92).move_to(CTR + UP * (RT + GAP_W / 2))
+            med = DoubleArrow(CTR + LEFT * RT, CTR + LEFT * (RT + GAP_W), buff=0,
+                              color=C_GREEN, stroke_width=6, tip_length=0.18)
+            val = Text("15,9 cm", font=FONT, font_size=42, weight=BOLD, color=C_GREEN)
             val.next_to(med, UP, buff=0.22)
             b.play(GrowArrow(med), FadeIn(val), run_time=0.7)
             b.play(FadeIn(gt, shift=RIGHT * 0.3), run_time=0.7)
 
         with self.beat(6) as b:
-            b.play(FadeOut(VGroup(radios, gt, med, val, esc)), run_time=0.4)
-            b.play(VGroup(tierra, cuerda).animate.scale(0.52).move_to(UP * 4.6),
+            b.play(FadeOut(VGroup(radios, gt, med, val, scale_f)), run_time=0.4)
+            b.play(VGroup(earth, rope).animate.scale(0.52).move_to(UP * 4.6),
                    run_time=0.6)
             f1 = MathTex(r"r = \frac{P}{2\pi}", color=WHITE).scale(1.6).move_to(UP * 1.5)
             b.play(Write(f1), run_time=1.0)
 
         with self.beat(7) as b:
-            f2 = MathTex(r"\Delta r = \frac{1\,\text{m}}{2\pi}", color=AMBAR)
+            f2 = MathTex(r"\Delta r = \frac{1\,\text{m}}{2\pi}", color=AMBER)
             f2.scale(1.6).move_to(DOWN * 0.5)
             b.play(Write(f2), run_time=1.1)
 
         with self.beat(8) as b:
-            f3 = MathTex(r"= 0{,}159\ \text{m} = 15{,}9\ \text{cm}", color=VERDE)
+            f3 = MathTex(r"= 0{,}159\ \text{m} = 15{,}9\ \text{cm}", color=C_GREEN)
             f3.scale(1.25).move_to(DOWN * 2.15)
             b.play(Write(f3), run_time=0.9)
-            nota = self.fit(Text("el tamaño del planeta no aparece", font=FONT,
-                                 font_size=40, weight=BOLD, color=ROSA), 8.2)
-            nota.move_to(DOWN * 3.05)
-            b.play(FadeIn(nota, shift=UP * 0.15), run_time=0.6)
+            note_txt = self.fit(Text("el tamaño del planeta no aparece", font=FONT,
+                                 font_size=40, weight=BOLD, color=C_PINK), 8.2)
+            note_txt.move_to(DOWN * 3.05)
+            b.play(FadeIn(note_txt, shift=UP * 0.15), run_time=0.6)
 
         with self.beat(9) as b:
-            b.play(FadeOut(VGroup(f1, f2, f3, nota, tierra, cuerda)), run_time=0.45)
-            def par(r, etiqueta, x, col):
+            b.play(FadeOut(VGroup(f1, f2, f3, note_txt, earth, rope)), run_time=0.45)
+            def pair_label(r, label, x, col):
                 c0 = [x, 1.75, 0]
-                p = self.planeta(r, c0, col)
-                c = Circle(radius=r + 0.30, stroke_width=6, color=AMBAR).move_to(c0)
-                lab = Text(etiqueta, font=FONT, font_size=36, weight=BOLD, color=WHITE)
+                p = self.planet(r, c0, col)
+                c = Circle(radius=r + 0.30, stroke_width=6, color=AMBER).move_to(c0)
+                lab = Text(label, font=FONT, font_size=36, weight=BOLD, color=WHITE)
                 lab.move_to([x, -0.55, 0])
-                v = Text("15,9 cm", font=FONT, font_size=38, weight=BOLD, color=VERDE)
+                v = Text("15,9 cm", font=FONT, font_size=38, weight=BOLD, color=C_GREEN)
                 v.move_to([x, -1.25, 0])
                 return VGroup(p, c, lab, v)
-            iz = par(1.25, "la Tierra", -2.05, "#1D3B6E")
-            de = par(0.55, "una pelota de tenis", 2.05, "#2F7A3C")
+            left_lab = pair_label(1.25, "la Tierra", -2.05, "#1D3B6E")
+            de = pair_label(0.55, "una pelota de tenis", 2.05, "#2F7A3C")
             self.fit(de[2], 3.9)
-            b.play(FadeIn(iz), run_time=0.6)
+            b.play(FadeIn(left_lab), run_time=0.6)
             b.play(FadeIn(de), run_time=0.6)
-            ig = Text("=", font=FONT, font_size=64, weight=BOLD, color=AMBAR)
+            ig = Text("=", font=FONT, font_size=64, weight=BOLD, color=AMBER)
             ig.move_to([0, 1.75, 0])
             b.play(FadeIn(ig, scale=0.6), run_time=0.5)
-            esc2 = Text("(no está a escala)", font=FONT, font_size=28, color=GRIS)
+            esc2 = Text("(no está a escala)", font=FONT, font_size=28, color=C_GRAY)
             esc2.move_to(DOWN * 2.35)
             b.play(FadeIn(esc2), run_time=0.35)
 
         with self.beat(10) as b:
-            b.play(FadeOut(VGroup(iz, de, ig, esc2)), run_time=0.4)
-            cta = VGroup(
+            b.play(FadeOut(VGroup(left_lab, de, ig, esc2)), run_time=0.4)
+            count_txt = VGroup(
                 self.fit(Text("el tamaño no importa", font=FONT, font_size=56,
-                              weight=BOLD, color=AMBAR), 8.0),
+                              weight=BOLD, color=AMBER), 8.0),
                 self.fit(Text("mandáselo al que dudó", font=FONT, font_size=44,
                               weight=BOLD, color=WHITE), 8.0),
             ).arrange(DOWN, buff=0.38).move_to(UP * 1.4)
-            b.play(Write(cta[0]), run_time=0.9)
-            b.play(FadeIn(cta[1], shift=UP * 0.15), run_time=0.6)
+            b.play(Write(count_txt[0]), run_time=0.9)
+            b.play(FadeIn(count_txt[1], shift=UP * 0.15), run_time=0.6)
 
         self.finish()