add: tmp commit

1 files changed, 31 insertions, 0 deletions

diff --git a/src/ballistics.c b/src/ballistics.c
index 10d97da..418318a 100644
--- a/src/ballistics.c
+++ b/src/ballistics.c
@@ -4,6 +4,12 @@
 #include "constants.h"
 #include "context.h"
 
+static inline double speed_of_sound(double temperature);
+static inline double calculate_retard(DragModel drag_function,
+									  double ballistic_coefficient,
+									  double velocity,
+									  double mach);
+
 double atmospheric_correction(double ballistic_coefficient,
 							  double temperature,
 							  double pressure,
@@ -36,3 +42,28 @@ double calculate_air_density(double temperature,
 	else
 		return pressure / (SPECIFIC_GAST_CONSTANT_DRY_AIR * temperature);
 }
+
+static inline double speed_of_sound(double temperature) {
+	return sqrt(331.3 * (1.0 + temperature - 273.15 / 273.15));
+}
+
+static inline double
+calculate_retard(DragModel ballistic_model,
+				 double ballistic_coefficient,
+                 double velocity,
+                 double mach)
+{
+	double m = velocity / mach;
+for (int i = 0
+}
+
+double retard(DragModel ballistic_model,
+			  double ballistic_coefficient,
+			  double velocity,
+			  double temperature)
+{
+	return calculate_retard(ballistic_model,
+							ballistic_coefficient,
+							velocity,
+							speed_of_sound(temperature));
+}