30 lines
809 B
Python
30 lines
809 B
Python
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from pygame import draw, mouse
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from .. import HEIGHT, WIDTH
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from ..colors import *
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from ..math import *
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class VecProj:
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title = "Vector Projection"
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def render(self, surface):
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x1 = WIDTH / 4
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y1 = HEIGHT / 2 + 100
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x2 = 0.75 * WIDTH
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y2 = HEIGHT / 2
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cx, cy = mouse.get_pos()
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lx, ly = x2 - x1, y2 - y1 # line vector
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llen = length(lx, ly)
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lnx, lny = lx / llen, ly / llen # line normal
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lcx, lcy = cx - x1, cy - y1 # line start - cursor vector
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proj = dot(lcx, lcy, lx, ly) / llen
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draw.line(
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surface, GREEN, (cx, cy), add(x1, y1, *scale(lnx, lny, proj)), 5
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)
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draw.line(surface, WHITE, (cx, cy), (x1, y1), 5)
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draw.line(surface, YELLOW, (x1, y1), (x2, y2), 5)
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