coordinates.hpp: serverToCanonicalYaw now computes s - π/2 instead of π/2 - s.
The codebase uses atan2(-dy, dx) as its canonical yaw convention, where server
direction (cos s, sin s) in (server_X, server_Y) becomes (sin s, cos s) in
canonical after the X/Y swap, giving atan2(-cos s, sin s) = s - π/2.
canonicalToServerYaw is updated as its proper inverse: c + π/2.
The old formula (π/2 - s) was self-inverse and gave the wrong east/west facing
for any NPC not pointing north or south.
game_screen.cpp: Nameplate NDC→screen Y no longer double-inverts. The camera
bakes the Vulkan Y-flip into the projection matrix (NDC y=-1 = screen top,
y=+1 = screen bottom), so sy = (ndc.y*0.5 + 0.5) * screenH is correct.
The previous formula subtracted from 1.0 which reflected nameplates vertically.
Teleporter panel (T key) lets the player teleport between Goldshire,
Stormwind Gate, Ironforge, and Westfall in single-player mode. Adds
serverToCanonical/canonicalToServer conversion at the network packet
boundary so positions are compatible with TrinityCore/MaNGOS/AzerothCore
emulator servers.
Centralizes all coordinate conversions in core/coordinates.hpp with
proper canonical WoW coords (+X=North, +Y=West, +Z=Up). Fixes critical
tile calculation bug that was loading wrong surrounding tiles during
terrain streaming, and fixes position sync sending ADT-raw format
instead of canonical coordinates to the server.
