Reputation: 66945
So I have a 8x8 square. There is a line in it.
Line size == 8 angle == 0.
One of line points is always on one of the top corners.
What would be a formula to retrieve points coordinates where line crosses borders of square? (positive angle means one of line points is 0, 0. negative 0, 8 )
What would be math formula for each of coordinates points? (in pseudo code if possible)
Upvotes: 3
Views: 6202
Reputation: 332
line_end_x = line_start_x + cos(angle)*line_length
line_end_y = line_start_y + sin(angle)*line_length
if your line crosses a vertical edge:
intersection_x = edge_x
intersection_y = line_start_y + (intersection_x - line_start_x) * tan(angle)
if your line crosses a horizontal edge:
intersection_y = edge_y
intersection_x = line_start_x + (intersection_y - line_start_y) * tan(angle-pi/4)
EDIT: corrected
Upvotes: 6