'''
Mission 14 - Line Art
Objective 9
'''
from codex import *

# Grid spacing (pixels)
GRID = 10

# Variables for screen center
x_center = int(display.width / 2)
y_center = int(display.height / 2)

# Draw a grid of white pixels
for y in range(0, display.height, GRID):
    for x in range(0, display.width, GRID):
        display.set_pixel(x, y, WHITE)

# Horizontal and vertical lines
display.draw_line(0, y_center, display.width, y_center, RED)        
display.draw_line(x_center, 0, x_center, display.height, RED)
# Blue border
display.draw_rect(0, 0, display.width, display.height, BLUE)

def draw_web(x1, y1, x2, y2, count, color):
    # Calculate the step size "deltas" for x and y
    dx1 = int((x2 - x1) / count)
    dy1 = int((y2 - y1) / count)
    dx2 = dy1
    dy2 = -dx1
    # Draw the line and move endpoints by dx, dy
    for i in range(count):
        display.draw_line(x1, y1, x2, y2, color)
        x1 = x1 + dx1
        y1 = y1 + dy1
        x2 = x2 + dx2
        y2 = y2 + dy2

# String art!
WEB_SPACING = 20
# outside webs
draw_web(0, 0, 0, 239, WEB_SPACING, GREEN)
draw_web(0, 239, 239, 239, WEB_SPACING, YELLOW)
draw_web(239, 239, 239, 0, WEB_SPACING, CYAN)
draw_web(239, 0, 0, 0, WEB_SPACING, MAGENTA)
# inside webs
draw_web(120, 0, 120, 120, WEB_SPACING, ORANGE)
draw_web(0, 120, 120, 120, WEB_SPACING, RED)
draw_web(120, 239, 120, 120, WEB_SPACING, WHITE)
draw_web(239, 120, 120, 120, WEB_SPACING, PINK)