Helicopter rotor collides at twice the rotor diameter

[stiansel]

Describe the bug

Helicopter rotor collision code appears to calculate collisions at twice the actual rotor diameter. This appears to be caused by using the diameter as radius:

Cataclysm-DDA/src/vehicle_move.cpp

Line 421 in f594632

for( const tripoint &rotor_point : g->m.points_in_radius( dsp, info.rotor_diameter() ) ) {

Steps To Reproduce

Came across this while flying for the first time and attempting to land a medevac helicopter at the military helipad map location. This helicopter has "small helicopter rotors" with a diameter of 8 according to the current rotor.json file. If I land with any object within (roughly) the purple circle the helicopter will crash. See attached screenshot.

This location has a two story building which I tested approaching at the 2nd floor. Getting any closer than 8(+1) squares from the rotor center caused the helicopter to crash with the wall. Note how the purple circle extends past the tailboom of the helicopter which appears to be a rare design choice in real life due to interfering with the (imaginary) tail rotor. As such I consider this a bug.

Expected behavior

Expect diameter/radius mismatch to be corrected and helicopter rotor diameter to fit within radius of tailboom on default heli designs. Would be helpful with an indicator of some kind to tell where the rotor is as I'm certain the player character has at least some idea from their position in the craft.

Another related issue: low objects like fuelpumps appear to cause rotor collisions which may not be intended.

Screenshots

Versions and configuration

• OS: Windows 7
• Game Version: 0.E-468-g9e02bc1
• Graphics version: Tiles
• Ingame language: English
• Mods loaded: dda, no_npc_food, aftershock, crt_expansion, magiclysm, alt_map_key, No_Fungi, fuji_mpp, StatsThroughSkills

PS: great job on the vehicle crashes, they're really quite spectacular. :)