map-machine/engine/flinger.py
2015-08-07 01:32:29 +03:00

120 lines
4.3 KiB
Python

#!/usr/bin/env python
"""
Author: Sergey Vartanov (me@enzet.ru)
"""
import math
import sys
sys.path.append('../lib')
from vector import Vector
class Flinger(object):
"""
Flinger. Coordinates repositioning.
"""
def __init__(self, minimum, maximum, target_minimum=None, target_maximum=None, ratio=None):
self.minimum = minimum
self.maximum = maximum
if not target_minimum:
target_minimum = Vector()
if not target_maximum:
target_maximum = maximum - minimum
space = Vector()
if ratio:
if ratio == 'geo':
ratio = math.sin((90.0 - ((self.maximum.y + self.minimum.y) / 2.0)) / 180.0 * math.pi)
current_ratio = (self.maximum.x - self.minimum.x) * ratio / (self.maximum.y - self.minimum.y)
target_ratio = (target_maximum.x - target_minimum.x) / (target_maximum.y - target_minimum.y)
if current_ratio >= target_ratio:
n = (target_maximum.x - target_minimum.x) / (maximum.x - minimum.x) / ratio
space.y = ((target_maximum.y - target_minimum.y) - (maximum.y - minimum.y) * n) / 2.0
space.x = 0
else:
n = (target_maximum.y - target_minimum.y) / (maximum.y - minimum.y)
space.x = ((target_maximum.x - target_minimum.x) - (maximum.x - minimum.x) * n) / 2.0
space.y = 0
target_minimum.x += space
target_maximum.x += space
self.target_minimum = target_minimum
self.target_maximum = target_maximum
def fling(self, current):
"""
Fling current point to the surface.
"""
x = map_(current.x, self.minimum.x, self.maximum.x, self.target_minimum.x, self.target_maximum.x)
y = map_(current.y, self.minimum.y, self.maximum.y, self.target_minimum.y, self.target_maximum.y)
return Vector(x, y)
class Geo:
def __init__(self, lat, lon):
self.lat = lat
self.lon = lon
def __add__(self, other):
return Geo(self.lat + other.lat, self.lon + other.lon)
def __sub__(self, other):
return Geo(self.lat - other.lat, self.lon - other.lon)
def __repr__(self):
return `self.lat` + ', ' + `self.lon`
class GeoFlinger:
def __init__(self, minimum, maximum, target_minimum=None, target_maximum=None):
self.minimum = minimum
self.maximum = maximum
# Ratio is depended of latitude. It is always <= 1.
# In one latitude degree is always 40 000 / 360 km.
# In one current longitude degree is about 40 000 / 360 * ratio km.
ratio = math.sin((90.0 - ((self.maximum.lat + self.minimum.lat) / 2.0)) / 180.0 * math.pi)
# Longitude displayed as x.
# Latitude displayed as y.
# Ratio is x / y.
space = Vector()
current_ratio = (self.maximum.lon - self.minimum.lon) * ratio / (self.maximum.lat - self.minimum.lat)
target_ratio = (target_maximum.x - target_minimum.x) / (target_maximum.y - target_minimum.y)
if current_ratio >= target_ratio:
n = (target_maximum.x - target_minimum.x) / (maximum.lon - minimum.lon) / ratio
space.y = ((target_maximum.y - target_minimum.y) - (maximum.lat - minimum.lat) * n) / 2.0
space.x = 0
else:
n = (target_maximum.y - target_minimum.y) / (maximum.lat - minimum.lat) * ratio
space.x = ((target_maximum.x - target_minimum.x) - (maximum.lon - minimum.lon) * n) / 2.0
space.y = 0
self.target_minimum = target_minimum + space
self.target_maximum = target_maximum - space
self.space = space
def fling(self, current):
x = map_(current.lon, self.minimum.lon, self.maximum.lon,
self.target_minimum.x, self.target_maximum.x)
y = map_(self.maximum.lat + self.minimum.lat - current.lat,
self.minimum.lat, self.maximum.lat,
self.target_minimum.y, self.target_maximum.y)
return Vector(x, y)
def map_(value, current_min, current_max, target_min, target_max):
"""
Map current value in bounds of current_min and current_max to bounds of target_min and target_max.
"""
return target_min + (value - current_min) / (current_max - current_min) * (target_max - target_min)