当你通过移动鼠标滚轮放大/缩小时,我试图模仿3dsmax的行为。在3ds Max中,此缩放将朝向鼠标位置。到目前为止,我已经想出了这个小的mcve:
import math
from ctypes import c_void_p
import numpy as np
from OpenGL.GL import *
from OpenGL.GLU import *
from OpenGL.GLUT import *
from glm import *
class Camera():
def __init__(
self,
eye=None, target=None, up=None,
fov=None, near=0.1, far=100000,
**kwargs
):
self.eye = vec3(eye) or vec3(0, 0, 1)
self.target = vec3(target) or vec3(0, 0, 0)
self.up = vec3(up) or vec3(0, 1, 0)
self.original_up = vec3(self.up)
self.fov = fov or radians(45)
self.near = near
self.far = far
def update(self, aspect):
self.view = lookAt(self.eye, self.target, self.up)
self.projection = perspective(self.fov, aspect, self.near, self.far)
def zoom(self, *args):
delta = -args[1] * 0.1
distance = length(self.target - self.eye)
self.eye = self.target + (self.eye - self.target) * (delta + 1)
def zoom_towards_cursor(self, *args):
x = args[2]
y = args[3]
v = glGetIntegerv(GL_VIEWPORT)
viewport = vec4(float(v[0]), float(v[1]), float(v[2]), float(v[3]))
height = viewport.z
p0 = vec3(x, height - y, 0.0)
p1 = vec3(x, height - y, 1.0)
v1 = unProject(p0, self.view, self.projection, viewport)
v2 = unProject(p1, self.view, self.projection, viewport)
world_from = vec3(
(-v1.z * (v2.x - v1.x)) / (v2.z - v1.z) + v1.x,
(-v1.z * (v2.y - v1.y)) / (v2.z - v1.z) + v1.y,
0.0
)
self.eye.z = self.eye.z * (1.0 + 0.1 * args[1])
view = lookAt(self.eye, self.target, self.up)
v1 = unProject(p0, view, self.projection, viewport)
v2 = unProject(p1, view, self.projection, viewport)
world_to = vec3(
(v1.z * (v2.x - v1.x)) / (v2.z - v1.z) + v1.x,
(-v1.z * (v2.y - v1.y)) / (v2.z - v1.z) + v1.y,
0.0
)
offset = world_to - world_from
print(self.eye.z, world_from, world_to, offset)
self.eye += offset
self.target += offset
class GlutController():
def __init__(self, camera):
self.camera = camera
self.zoom = self.camera.zoom
def glut_mouse_wheel(self, *args):
self.zoom(*args)
class MyWindow:
def __init__(self, w, h):
self.width = w
self.height = h
glutInit()
glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB | GLUT_DEPTH)
glutInitWindowSize(w, h)
glutCreateWindow('OpenGL Window')
self.startup()
glutReshapeFunc(self.reshape)
glutDisplayFunc(self.display)
glutMouseWheelFunc(self.controller.glut_mouse_wheel)
glutKeyboardFunc(self.keyboard_func)
glutIdleFunc(self.idle_func)
def keyboard_func(self, *args):
try:
key = args[0].decode("utf8")
if key == "\x1b":
glutLeaveMainLoop()
if key in ['1']:
self.controller.zoom = self.camera.zoom
print("Using normal zoom")
elif key in ['2']:
self.controller.zoom = self.camera.zoom_towards_cursor
print("Using zoom towards mouse")
except Exception as e:
import traceback
traceback.print_exc()
def startup(self):
glEnable(GL_DEPTH_TEST)
aspect = self.width / self.height
params = {
"eye": vec3(10, 10, 10),
"target": vec3(0, 0, 0),
"up": vec3(0, 1, 0)
}
self.cameras = [
Camera(**params)
]
self.camera = self.cameras[0]
self.model = mat4(1)
self.controller = GlutController(self.camera)
def run(self):
glutMainLoop()
def idle_func(self):
glutPostRedisplay()
def reshape(self, w, h):
glViewport(0, 0, w, h)
self.width = w
self.height = h
def display(self):
self.camera.update(self.width / self.height)
glClearColor(0.2, 0.3, 0.3, 1.0)
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT)
glMatrixMode(GL_PROJECTION)
glLoadIdentity()
gluPerspective(degrees(self.camera.fov), self.width / self.height, self.camera.near, self.camera.far)
glMatrixMode(GL_MODELVIEW)
glLoadIdentity()
e = self.camera.eye
t = self.camera.target
u = self.camera.up
gluLookAt(e.x, e.y, e.z, t.x, t.y, t.z, u.x, u.y, u.z)
glColor3f(1, 1, 1)
glBegin(GL_LINES)
for i in range(-5, 6):
if i == 0:
continue
glVertex3f(-5, 0, i)
glVertex3f(5, 0, i)
glVertex3f(i, 0, -5)
glVertex3f(i, 0, 5)
glEnd()
glBegin(GL_LINES)
glColor3f(1, 1, 1)
glVertex3f(-5, 0, 0)
glVertex3f(0, 0, 0)
glVertex3f(0, 0, -5)
glVertex3f(0, 0, 0)
glColor3f(1, 0, 0)
glVertex3f(0, 0, 0)
glVertex3f(5, 0, 0)
glColor3f(0, 1, 0)
glVertex3f(0, 0, 0)
glVertex3f(0, 5, 0)
glColor3f(0, 0, 1)
glVertex3f(0, 0, 0)
glVertex3f(0, 0, 5)
glEnd()
glutSwapBuffers()
if __name__ == '__main__':
window = MyWindow(800, 600)
window.run()
在这段代码中,您可以通过按“1”或“2”键在两种缩放模式之间切换。
按“1”时,我正在进行标准缩放,目前为止效果不错。
问题是当按下“2”时,在本例中,我尝试修改来自此的代码
thread
对于python/pyopengl/pygml,但是因为我不太了解这个答案的基本数学知识,所以我不太清楚如何解决这种不良行为。
如何修复发布的代码,使其像3dsmax一样正确地放大/缩小鼠标?
