pygame通过重心坐标 用纹理填充三角形

texture_x = int(alpha * texture_image.get_width())
texture_y = int(beta * texture_image.get_height())为什么没有gama

2024/3/30 15:45:52

在使用重心坐标进行纹理映射时，通常是通过计算 alpha 和 beta 来确定纹理图片上的对应位置，而 gamma 通常是通过 alpha 和 beta 相互关系来计算的，因为重心坐标满足 alpha + beta + gamma = 1。因此，通常情况下不需要单独计算 gamma，因为它可以通过 alpha 和 beta 推导得到，从而减少了计算的复杂性和冗余。

import pygame
from pygame.locals import *
import sys
import mathpygame.init()width, height = 800, 600
screen = pygame.display.set_mode((width, height))vertices = [(160, 300, 1), (400, 40, 1), (600, 300, 1)]angle = 0
rotation_speed = 2  # 可根据需要调整旋转速度
c=pygame.time.Clock()
f=False
suofang=100
ax=0
ay=0
bx=0
by=0
cx=0
cy=0ci=0
zx=0
zy=0
zhongxina=0
zhongxinb=0
zhongxinc=0img=pygame.image.load("1.png").convert_alpha()
def draw_triangle(vertices):#points = [rotate_point(vertex, angle) for vertex in vertices]global ciglobal axglobal ayglobal bxglobal byglobal cxglobal cypoints = []new_vertices = []for x, y, z in vertices:new_x = x * math.cos(math.radians(angle)) - z * math.sin(math.radians(angle))new_z = x * math.sin(math.radians(angle)) + z * math.sin(math.radians(angle))new_vertices.append((new_x, y, new_z))(ax, ay, az), (bx, by, bz), (cx, cy, cz) = new_vertices#print(p,';;')# 绘制多边形#pygame.draw.polygon(screen, (200, 200, 200), transformed_points)#print(transformed_points)while True:screen.fill((255, 255, 255))#c.tick(7)for event in pygame.event.get():if event.type == QUIT:pygame.quit()sys.exit()keys = pygame.key.get_pressed()if keys[pygame.K_UP]:f = Trueif event.type == pygame.KEYUP:f = Falseif f==True:suofang=suofang-10draw_triangle(vertices)#angle += rotation_speed#print("....","ax",ax ,"ay",ay,"bx",bx,"by",by,"cx",cx,"cy",cy)for h in range(600):for w in range(600):zx = wzy = h# 重心坐标在求出中心后就不需要了，后面需要用这个坐标来判断屏幕中每个像素是否在三角形内#print(zx,zy)za1 = -(zx - bx) * (cy - by) + (zy - by) * (cx - bx)za2 = -(ax - bx) * (cy - by) + (ay - by) * (cx - bx)zhongxina = za1 / za2zb1 = -(zx - cx) * (ay - cy) + (zy - cy) * (ax - cx)zb2 = -(bx - cx) * (ay - cy) + (by - cy) * (ax - cx)zhongxinb = zb1 / zb2zhongxinc = 1 - zhongxina - zhongxinbif (0<zhongxina<1 and 0<zhongxinb<1 and 0<zhongxinc<1):#print(h,w)pygame.Surface.set_at(screen, (int(w), int(h)),(img.get_at((int(zhongxina*img.get_width()),int((zhongxinb*img.get_height()))))))#(img.get_at((int(i/10),int(gao/10)))))# zx =(ax + bx + cx) / 3# zy =(ay + by + cy) / 3# #重心坐标在求出中心后就不需要了，后面需要用这个坐标来判断屏幕中每个像素是否在三角形内## '''# x,y=500  abc三点不满足大于0小于1# -0.7076923076923077# 1.3282051282051281# 0.3794871794871797# 1.0## x,y=143 都满足大于0小于1，在三角形内# 0.94 0.04666666666666667 0.013333333333333384 1.0## x,y=300 都满足，在三角形内# 0.2153846153846154 0.6102564102564103 0.1743589743589743 1.0## x,y=0 不满足，不在三角形内# 1.6 -0.4666666666666667 -0.13333333333333341 0.9999999999999999## x=770,y=143 不满足 不在三角形内# -0.6676923076923077 -1.0251282051282051 2.692820512820513 1.0##  x=230,y=190满足，在#  0.6205128205128205 0.147008547008547 0.23247863247863246 1.0# '''# za1=-(zx-bx)*(cy-by)+(zy-by)*(cx-bx)# za2=-(ax-bx)*(cy-by)+(ay-by)*(cx-bx)# zhongxina=za1/za2## zb1=-(zx-cx)*(ay-cy)+(zy-cy)*(ax-cx)# zb2=-(bx-cx)*(ay-cy)+(by-cy)*(ax-cx)# zhongxinb=zb1/zb2## zhongxinc=1-zhongxina-zhongxinb#print(zhongxina,zhongxinb,zhongxinc,zhongxina+zhongxinb+zhongxinc,"zx,",zx,"zy",zy)pygame.Surface.set_at(screen, (int(zx), int(zy)),(190, 90, 90))pygame.display.flip()