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TAXIROUTE_LINEFACTOR = 32/30; -- Multiplying factor for texture coordinates
TAXIROUTE_LINEFACTOR_2 = TAXIROUTE_LINEFACTOR / 2; -- Half o that

-- T        - Texture
-- C        - Canvas Frame (for anchoring)
-- sx,sy    - Coordinate of start of line
-- ex,ey    - Coordinate of end of line
-- w        - Width of line
-- relPoint - Relative point on canvas to interpret coords (Default BOTTOMLEFT)
function DrawRouteLine(T, C, sx, sy, ex, ey, w, relPoint)
   if (not relPoint) then relPoint = "BOTTOMLEFT"; end

   -- Determine dimensions and center point of line
   local dx,dy = ex - sx, ey - sy;
   local cx,cy = (sx + ex) / 2, (sy + ey) / 2;

   -- Normalize direction if necessary
   if (dx < 0) then
      dx,dy = -dx,-dy;
   end

   -- Calculate actual length of line
   local l = sqrt((dx * dx) + (dy * dy));

   -- Quick escape if it's zero length
   if (l == 0) then
      T:SetTexCoord(0,0,0,0,0,0,0,0);
      T:SetPoint("BOTTOMLEFT", C, relPoint, cx,cy);
      T:SetPoint("TOPRIGHT",   C, relPoint, cx,cy);
      return;
   end

   -- Sin and Cosine of rotation, and combination (for later)
   local s,c = -dy / l, dx / l;
   local sc = s * c;

   -- Calculate bounding box size and texture coordinates
   local Bwid, Bhgt, BLx, BLy, TLx, TLy, TRx, TRy, BRx, BRy;
   if (dy >= 0) then
      Bwid = ((l * c) - (w * s)) * TAXIROUTE_LINEFACTOR_2;
      Bhgt = ((w * c) - (l * s)) * TAXIROUTE_LINEFACTOR_2;
      BLx, BLy, BRy = (w / l) * sc, s * s, (l / w) * sc;
      BRx, TLx, TLy, TRx = 1 - BLy, BLy, 1 - BRy, 1 - BLx;
      TRy = BRx;
   else
      Bwid = ((l * c) + (w * s)) * TAXIROUTE_LINEFACTOR_2;
      Bhgt = ((w * c) + (l * s)) * TAXIROUTE_LINEFACTOR_2;
      BLx, BLy, BRx = s * s, -(l / w) * sc, 1 + (w / l) * sc;
      BRy, TLx, TLy, TRy = BLx, 1 - BRx, 1 - BLx, 1 - BLy;
      TRx = TLy;
   end

   -- Set texture coordinates and anchors
   T:ClearAllPoints();
   T:SetTexCoord(TLx, TLy, BLx, BLy, TRx, TRy, BRx, BRy);
   T:SetPoint("BOTTOMLEFT", C, relPoint, cx - Bwid, cy - Bhgt);
   T:SetPoint("TOPRIGHT",   C, relPoint, cx + Bwid, cy + Bhgt);
end