clean up "static" and "constexpr" types

- use `static constexpr inline' to avoid requiring
  explicit declarations in object code
- use `const Foo* const' to maybe put into readonly
  binary segment (at least for ELF DSOs)
- `constexpr' in function scope has storage, avoid
  `static'
- don't use `constexpr' where there's no advantage,
  like arrays

We'd like to avoid overhead of atomic initialization
for each function call. No idea how `static constexpr'
requiring storage in the standard plays with atomic
initialization requirement. Hearsay points that
`constexpr' without `static' in block scope behaves
more to our liking. It's all hazy though.

I'm not 100% sure if `static inline constexpr' has any
storage. Hopefully none, like a #define, and stuff
bigger than registers gets coalesced within the same
module, with small stuff being immediates.

1 files changed, 26 insertions, 0 deletions

diff --git a/tracker-aruco/ftnoir_tracker_aruco.cpp b/tracker-aruco/ftnoir_tracker_aruco.cpp
index c322d323..faa8bb44 100644
--- a/tracker-aruco/ftnoir_tracker_aruco.cpp
+++ b/tracker-aruco/ftnoir_tracker_aruco.cpp
@@ -33,6 +33,32 @@
 #include <algorithm>
 #include <iterator>
 
+static const int adaptive_sizes[] =
+{
+#if defined USE_EXPERIMENTAL_CANNY
+    10,
+    30,
+    80,
+#else
+    7,
+    9,
+    13,
+#endif
+};
+
+struct resolution_tuple
+{
+    int width;
+    int height;
+};
+
+static const resolution_tuple resolution_choices[] =
+{
+    { 640, 480 },
+    { 320, 240 },
+    { 0, 0 }
+};
+
 aruco_tracker::aruco_tracker()
 {
     cv::setBreakOnError(true);