Fixing arrow events to draw head

This commit is contained in:
2025-09-19 16:22:44 -05:00
parent f34cf69b8c
commit f15b1a9990

View File

@@ -1,4 +1,5 @@
# Python imports
import math
# Lib imports
import cairo
@@ -33,12 +34,49 @@ class Arrow(BrushEvent):
def process(self, brush: cairo.Context):
brush.set_line_width(self.size)
brush.set_line_cap(1) # 0 = BUTT, 1 = ROUND, 2 = SQUARE
brush.set_source_rgba(*self.color)
brush.set_operator(cairo.OPERATOR_OVER);
brush.move_to(self.points[0].x, self.points[0].y)
brush.line_to(self.points[1].x, self.points[1].y)
x1, y1 = self.points[0].x, self.points[0].y
x2, y2 = self.points[1].x, self.points[1].y
# Arrow body
brush.move_to(x1, y1)
brush.line_to(x2, y2)
# Arrow head
ah1, ay1, \
ah2, ay2 = self.get_arrow_head_points(x1, y1, x2, y2)
brush.move_to(x2, y2)
brush.line_to(ah1, ay1)
brush.move_to(x2, y2)
brush.line_to(ah2, ay2)
brush.stroke()
def get_arrow_head_points(self, x1, y1, x2, y2, arrow_head_length = 25, arrow_angle = 45):
# Convert angle to radians
angle_rad = math.radians(arrow_angle)
# Calculate the angle of the main line
line_angle = math.atan2(y2 - y1, x2 - x1)
# Arrowhead angles (one on each side of the line)
angle1 = line_angle + math.pi - angle_rad
angle2 = line_angle + math.pi + angle_rad
# Calculate the two arrowhead points
p1 = (
x2 + arrow_head_length * math.cos(angle1),
y2 + arrow_head_length * math.sin(angle1)
)
p2 = (
x2 + arrow_head_length * math.cos(angle2),
y2 + arrow_head_length * math.sin(angle2)
)
return *p1, *p2