#!/usr/bin/env python
# coding: utf-8

# # Geodesic lines on livemap: `flat` parameter.
# 
# 
# Parameter `flat` enables or disables geodesic lines on livemap.
# 
# Layers that support `flat` parameter are `geom_segment()` and `geom_path()`:
# 
# - `False` (by default) - allows projection to curve a line
# - `True` - keeps a line flat

# In[1]:


from lets_plot import *


# In[2]:


LetsPlot.setup_html()


# In[3]:


data = {
    'lon': [-73.7997, -149.9002],
    'lat': [40.6408, 61.2180],
}


# #### 1. Default Presentation
# 
# By default a geodesic is drawn for `geom_path()` and `geom_segment()` on livemap. It is the shortest path between points on earth.

# In[4]:


ggplot(data, aes(x='lon', y='lat')) + \
    geom_livemap() + \
    geom_path()


# #### 2. With flat=True
# 
# If it is necessary to indicate distances for example, travel routes, a straight line is better. This is how `geom_path()` is rendered with parameter `flat=True` on livemap.

# In[5]:


ggplot(data, aes(x='lon', y='lat')) + \
    geom_livemap() + \
    geom_path(flat=True)