new image: tetraeder

1 files changed, 116 insertions, 0 deletions

diff --git a/buch/chapters/95-homologie/images/tetraeder.pov b/buch/chapters/95-homologie/images/tetraeder.pov
new file mode 100644
index 0000000..b110f96
--- /dev/null
+++ b/buch/chapters/95-homologie/images/tetraeder.pov
@@ -0,0 +1,116 @@
+//
+// tetraeder.pov
+//
+// (c) 2021 Prof Dr Andreas Müller, OST Ostschweizer Fachhochschule
+//
+#version 3.7;
+#include "colors.inc"
+
+global_settings {
+	assumed_gamma 1
+}
+
+#declare imagescale = 0.169;
+#declare O = <0, 0, 0>;
+#declare at = 0.02;
+
+camera {
+	location <-2, 3, -10>
+	look_at <0, 0.18, 0>
+	right 16/9 * x * imagescale
+	up y * imagescale
+}
+
+//light_source {
+//      <-14, 20, -50> color White
+//      area_light <1,0,0> <0,0,1>, 10, 10
+//      adaptive 1
+//      jitter
+//}
+
+light_source {
+	<-41, 20, -20> color White
+	area_light <1,0,0> <0,0,1>, 10, 10
+	adaptive 1
+	jitter
+}
+
+sky_sphere {
+	pigment {
+		color rgb<1,1,1>
+	}
+}
+
+#declare v1 = <1,1,1>;
+#declare v2 = <-1,1,-1>;
+#declare farbe = rgbf<0.8,0.8,1.0,0.5>;
+
+#declare tetraederwinkel = acos(vdot(v1,v2)/(vlength(v1)*vlength(v2)));
+
+#declare O = < 0, 0, 0 >;
+#declare A = < 0, 1, 0 >;
+#declare B = < sin(tetraederwinkel), cos(tetraederwinkel), 0>;
+#declare C = < sin(tetraederwinkel)*cos(2*pi/3), cos(tetraederwinkel),  sin(2*pi/3)>;
+#declare D = < sin(tetraederwinkel)*cos(2*pi/3), cos(tetraederwinkel), -sin(2*pi/3)>;
+
+#macro arrow(from, to, arrowthickness, c)
+#declare arrowdirection = vnormalize(to - from);
+#declare arrowlength = vlength(to - from);
+union {
+	sphere {
+		from, 1.0 * arrowthickness
+	}
+	cylinder {
+		from,
+		from + (arrowlength - 8 * arrowthickness) * arrowdirection,
+		arrowthickness
+	}
+	cone {
+		from + (arrowlength - 8 * arrowthickness) * arrowdirection,
+		2 * arrowthickness,
+		to - 3 * arrowthickness * arrowdirection,
+		0
+	}
+	pigment {
+		color c
+	}
+	finish {
+		specular 0.9
+		metallic
+	}
+}
+#end
+
+union {
+	arrow(B, C, at, White)
+	arrow(D, C, at, White)
+	arrow(D, B, at, White)
+	arrow(B, A, at, White)
+	arrow(C, A, at, White)
+	arrow(D, A, at, White)
+	sphere { A, 4 * at }
+	sphere { B, 4 * at }
+	sphere { C, 4 * at }
+	sphere { D, 4 * at }
+	pigment {
+		color White
+	}
+	finish {
+		specular 0.9
+		metallic
+	}
+}
+
+mesh {
+	triangle { A, B, C }
+	triangle { A, C, D }
+	triangle { A, D, B }
+	triangle { B, C, D }
+	pigment {
+		color farbe
+	}
+//	finish {
+//		specular 0.9
+//		metallic
+//	}
+}