Make pinhole.hpp robust against min/max preprocessor macros (typically from windows.h)

rerun_cpp/src/rerun/archetypes/pinhole_ext.cpp

@@ -36,7 +36,8 @@ namespace rerun {
         /// Assumes the principal point to be in the middle of the sensor.
         static Pinhole from_fov_and_aspect_ratio(float fov_y, float aspect_ratio) {
             const float EPSILON = std::numeric_limits<float>::epsilon();
-            const float focal_length_y = 0.5f / std::tan(std::max(fov_y * 0.5f, EPSILON));
+            // `max` has explicit template args to avoid preprocessor replacement when <windows.h> is included without NOMINMAX.
+            const float focal_length_y = 0.5f / std::tan(std::max<float>(fov_y * 0.5f, EPSILON));
             return from_focal_length_and_resolution(
                 {focal_length_y, focal_length_y},
                 {aspect_ratio, 1.0}

rerun_cpp/tests/windows_min_max_robustness.cpp

@@ -0,0 +1,10 @@
+
+// `<windows.h>` by default defined min and max as macros, which can cause issues with std::min and std::max.
+// This can be easily turned off by the user with `#define NOMINMAX` before including `<windows.h>`.
+// However, users might not know about this or forget about it and we want to be robust against it.
+//
+// This test checks that rerun.h is robust against this issue by explicitly setting `min`/`max` macros and including rerun.hpp.
+#define min(a, b) (this does not compile)
+#define max(a, b) (this does not compile)
+
+#include <rerun.hpp>