Make 3D axes correspond to places in binary representation (allows for more generic...

diff --git a/src/box3d-face.cpp b/src/box3d-face.cpp
index 13e19d769a81bcd90edad7543e800aa5ef83a14a..8b3b5d96886a578428976c568b42aee636e81fea 100644 (file)
--- a/src/box3d-face.cpp
+++ b/src/box3d-face.cpp
@@ -30,13 +30,7 @@ void Box3DFace::set_shape(NR::Point const ul, NR::Point const lr,
         corners[2] = lr;
     } else {
         if (align_along_PL) {
-               Box3D::PerspDir dir3;
-            if (dir1 == Box3D::X && dir2 == Box3D::Z) dir3 = Box3D::Y;
-            if (dir1 == Box3D::X && dir2 == Box3D::Y) dir3 = Box3D::Z;
-            if (dir1 == Box3D::Z && dir2 == Box3D::X) dir3 = Box3D::Y;
-            if (dir1 == Box3D::Z && dir2 == Box3D::Y) dir3 = Box3D::X;
-            if (dir1 == Box3D::Y && dir2 == Box3D::X) dir3 = Box3D::Z;
-            if (dir1 == Box3D::Y && dir2 == Box3D::Z) dir3 = Box3D::X;
+            Box3D::PerspDir dir3 = Box3D::third_axis_direction (dir1, dir2);
             Box3D::Line line1(*SP3DBoxContext::current_perspective->get_vanishing_point(dir1), lr);
             Box3D::Line line2(*pt_align, *SP3DBoxContext::current_perspective->get_vanishing_point(dir3));
             corners[2] = *line1.intersect(line2);

diff --git a/src/vanishing-point.h b/src/vanishing-point.h
index 4770c74f1b74e7d00ada0853c1bbf3a984482816..de06002e4ddc47e188dc280d985e2468c04bdb63 100644 (file)
--- a/src/vanishing-point.h
+++ b/src/vanishing-point.h
@@ -22,13 +22,22 @@ enum VPState {
     VP_INFINITE    // perspective lines are parallel
 };
 
+// The X-/Y-/Z-axis corresponds to the first/second/third digit
+// in binary representation, respectively.
 enum PerspDir {
-    X,
-    Y,
-    Z,
-    NONE
+    X = 1,
+    Y = 2,
+    Z = 4,
+    NONE = 0
 };
 
+
+/** Given two axis directions out of {X, Y, Z}, returns the remaining one */
+inline Box3D::PerspDir third_axis_direction (Box3D::PerspDir dir1, Box3D::PerspDir dir2) {
+    return (Box3D::PerspDir) ((dir1 + dir2) ^ 0x7);
+}
+
+
 // FIXME: Store the PerspDir of the VP inside the class
 class VanishingPoint : public NR::Point {
 public: