Detector2D now parameterized through width and center in phi,alpha (#854)

Some code duplication in the GUI (Axis -> Span property and form), to be revised later.

Resolves #854 (closed).

Device/Detector/Detector2D.cpp

@@ -24,15 +24,16 @@
 
 using std::numbers::pi;
 
-Detector2D::Detector2D(size_t n_phi, double phi_min, double phi_max, size_t n_alpha,
-                       double alpha_min, double alpha_max)
-    : IDetector(new Frame(newEquiDivision("phi_f (rad)", n_phi, phi_min, phi_max),
-                          newEquiDivision("alpha_f (rad)", n_alpha, alpha_min, alpha_max)))
+Detector2D::Detector2D(double phi_full_width, double alpha_full_width, size_t n_phi, size_t n_alpha,
+                       double phi_center, double alpha_center)
+    : IDetector(
+        new Frame(newEquiDivision("phi_f (rad)", n_phi, phi_center - phi_full_width / 2,
+                                  phi_center + phi_full_width / 2),
+                  newEquiDivision("alpha_f (rad)", n_alpha, alpha_center - alpha_full_width / 2,
+                                  alpha_center + alpha_full_width / 2)))
 {
-    ASSERT(-pi / 2 < phi_min && phi_min < +pi / 2);
-    ASSERT(-pi / 2 < phi_max && phi_max < +pi / 2);
-    ASSERT(-pi / 2 < alpha_min && alpha_min < +pi / 2);
-    ASSERT(-pi / 2 < alpha_max && alpha_max < +pi / 2);
+    ASSERT(-pi / 2 < axis(0).min() && axis(0).max() < +pi / 2);
+    ASSERT(-pi / 2 < axis(1).min() && axis(1).max() < +pi / 2);
 }
 
 Detector2D* Detector2D::clone() const