如何在 PyOpenGL 上创建一个可以对鼠标移动进行“透视旋转”的相机？
Noa*_*oah 5 python opengl pygame pyopengl opengl-compat
我正在创建一个第一人称视角 RPG，我想在移动鼠标时在 PyOpenGL 中旋转相机（就像其他一些游戏，如 Minecraft）。我可以使用什么功能来做到这一点以及如何做到这一点？
我尝试使用gluLookAt()但我不明白它是如何工作的，尽管我经历了不同的来源。我什至不知道它是否有帮助。
import sys,pygame
from OpenGL.GL import *
from OpenGL.GLU import *
cmddown = False
#...
keypress = pygame.key.get_pressed()#Move using WASD
if keypress[pygame.K_w]:
glTranslatef(0,0,0.1)
if keypress[pygame.K_s]:
glTranslatef(0,0,-0.1)
if keypress[pygame.K_d]:
glTranslatef(-0.1,0,0)
if keypress[pygame.K_a]:
glTranslatef(0.1,0,0)
mouse_movement = pygame.mouse.get_rel()#Get mouse event
#This is where the "look around" should be happen
pygame.display.flip()
您可以使用glRotate围绕轴旋转，旋转量由相对鼠标移动 ( pygame.mouse.get_rel()) 给出：
mouseMove = pygame.mouse.get_rel()
glRotatef(mouseMove[0]*0.1, 0.0, 1.0, 0.0)
但这不会让您满意，因为如果鼠标离开窗口，该解决方案将不再起作用。
您必须pygame.mouse.set_pos()在每一帧中将鼠标置于屏幕中间。通过pygame.MOUSEMOTION事件获取鼠标移动。例如：
# init mouse movement and center mouse on screen
displayCenter = [scree.get_size()[i] // 2 for i in range(2)]
mouseMove = [0, 0]
pygame.mouse.set_pos(displayCenter)
paused = False
run = True
while run:
for event in pygame.event.get():
if event.type == pygame.QUIT:
run = False
if event.type == pygame.KEYDOWN:
if event.key == pygame.K_ESCAPE or event.key == pygame.K_RETURN:
run = False
if event.key == pygame.K_PAUSE or event.key == pygame.K_p:
paused = not paused
pygame.mouse.set_pos(displayCenter)
if event.type == pygame.MOUSEMOTION:
mouseMove = [event.pos[i] - displayCenter[i] for i in range(2)]
if not paused:
pygame.mouse.set_pos(displayCenter)
请注意，该操作，如glRotate 与glTranslate设置由新矩阵的矩阵乘法和当前矩阵。
currentMatrix = currentMatrix * newMatrix
这对于模型动画和变换来说是完美的，但对于第一人称运动来说这是错误的方式，必须改变相机的位置和视角。
viewMatrix = viewTransformMatrix * viewMatrix
做这样的操作glGetFloatv(GL_MODELVIEW_MATRIX)和glMultMatrixf。
初始化视图矩阵 bygluLookAt并将视图矩阵加载到变量 ( viewMatrix) by glGetFloatv(GL_MODELVIEW_MATRIX)，在主循环之前。
在每一帧的主循环中：
- 加载单位矩阵(
glLoadIdentity) - 对视图进行新的转换 (
glRotatef,glTranslatef) - 将当前视图矩阵乘以
viewMatrix(glMultMatrixf) viewMatrix为下一帧加载新的视图矩阵
glMatrixMode(GL_MODELVIEW)
gluLookAt(0, -8, 0, 0, 0, 0, 0, 0, 1)
viewMatrix = glGetFloatv(GL_MODELVIEW_MATRIX)
glLoadIdentity()
# [...]
run = True
while run:
# [...]
# init the view matrix
glLoadIdentity()
# apply the movment
if keypress[pygame.K_w]:
glTranslatef(0,0,0.1)
if keypress[pygame.K_s]:
glTranslatef(0,0,-0.1)
if keypress[pygame.K_d]:
glTranslatef(-0.1,0,0)
if keypress[pygame.K_a]:
glTranslatef(0.1,0,0)
# apply the roation
glRotatef(mouseMove[0]*0.1, 0.0, 1.0, 0.0)
# multiply the current matrix by the get the new view matrix and store the final vie matrix
glMultMatrixf(viewMatrix)
viewMatrix = glGetFloatv(GL_MODELVIEW_MATRIX)
为了向上和向下查找，您必须围绕 x 轴应用最终旋转。旋转的支点取决于视角。角度必须相加，并且必须在视图矩阵之后应用旋转，否则运动会根据角度改变（“高度”）级别。
viewMatrix = viewTransformMatrix * viewMatrix
finlalMatrix = lookUpDownMatrix * viewMatrix
为此，您必须将上下旋转矩阵联合起来并将其乘以 viewMatrix
up_down_angle = 0.0
run = True
while run:
# [...]
# init model view matrix
glLoadIdentity()
# apply the look up and down
up_down_angle += mouseMove[1]*0.1
glRotatef(up_down_angle, 1.0, 0.0, 0.0)
# init the view matrix
glPushMatrix()
glLoadIdentity()
# calculate new `viewMatrix`
# [...]
# apply view matrix
glPopMatrix()
glMultMatrixf(viewMatrix)
请参阅以下示例程序，该程序演示了该过程。
请注意，程序将鼠标保持在窗口的中心，因此您不能再“移动”鼠标。因此，应用程序可以通过ESC或停止return。
应用程序可以暂停pause或p。当应用程序暂停时，鼠标不会以窗口为中心。
import pygame
from pygame.locals import *
from OpenGL.GL import *
from OpenGL.GLU import *
import math
pygame.init()
display = (400, 300)
scree = pygame.display.set_mode(display, DOUBLEBUF | OPENGL)
glEnable(GL_DEPTH_TEST)
glEnable(GL_LIGHTING)
glShadeModel(GL_SMOOTH)
glEnable(GL_COLOR_MATERIAL)
glColorMaterial(GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE)
glEnable(GL_LIGHT0)
glLightfv(GL_LIGHT0, GL_AMBIENT, [0.5, 0.5, 0.5, 1])
glLightfv(GL_LIGHT0, GL_DIFFUSE, [1.0, 1.0, 1.0, 1])
sphere = gluNewQuadric()
glMatrixMode(GL_PROJECTION)
gluPerspective(45, (display[0]/display[1]), 0.1, 50.0)
glMatrixMode(GL_MODELVIEW)
gluLookAt(0, -8, 0, 0, 0, 0, 0, 0, 1)
viewMatrix = glGetFloatv(GL_MODELVIEW_MATRIX)
glLoadIdentity()
# init mouse movement and center mouse on screen
displayCenter = [scree.get_size()[i] // 2 for i in range(2)]
mouseMove = [0, 0]
pygame.mouse.set_pos(displayCenter)
up_down_angle = 0.0
paused = False
run = True
while run:
for event in pygame.event.get():
if event.type == pygame.QUIT:
run = False
if event.type == pygame.KEYDOWN:
if event.key == pygame.K_ESCAPE or event.key == pygame.K_RETURN:
run = False
if event.key == pygame.K_PAUSE or event.key == pygame.K_p:
paused = not paused
pygame.mouse.set_pos(displayCenter)
if not paused:
if event.type == pygame.MOUSEMOTION:
mouseMove = [event.pos[i] - displayCenter[i] for i in range(2)]
pygame.mouse.set_pos(displayCenter)
if not paused:
# get keys
keypress = pygame.key.get_pressed()
#mouseMove = pygame.mouse.get_rel()
# init model view matrix
glLoadIdentity()
# apply the look up and down
up_down_angle += mouseMove[1]*0.1
glRotatef(up_down_angle, 1.0, 0.0, 0.0)
# init the view matrix
glPushMatrix()
glLoadIdentity()
# apply the movment
if keypress[pygame.K_w]:
glTranslatef(0,0,0.1)
if keypress[pygame.K_s]:
glTranslatef(0,0,-0.1)
if keypress[pygame.K_d]:
glTranslatef(-0.1,0,0)
if keypress[pygame.K_a]:
glTranslatef(0.1,0,0)
# apply the left and right rotation
glRotatef(mouseMove[0]*0.1, 0.0, 1.0, 0.0)
# multiply the current matrix by the get the new view matrix and store the final vie matrix
glMultMatrixf(viewMatrix)
viewMatrix = glGetFloatv(GL_MODELVIEW_MATRIX)
# apply view matrix
glPopMatrix()
glMultMatrixf(viewMatrix)
glLightfv(GL_LIGHT0, GL_POSITION, [1, -1, 1, 0])
glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT)
glPushMatrix()
glColor4f(0.5, 0.5, 0.5, 1)
glBegin(GL_QUADS)
glVertex3f(-10, -10, -2)
glVertex3f(10, -10, -2)
glVertex3f(10, 10, -2)
glVertex3f(-10, 10, -2)
glEnd()
glTranslatef(-1.5, 0, 0)
glColor4f(0.5, 0.2, 0.2, 1)
gluSphere(sphere, 1.0, 32, 16)
glTranslatef(3, 0, 0)
glColor4f(0.2, 0.2, 0.5, 1)
gluSphere(sphere, 1.0, 32, 16)
glPopMatrix()
pygame.display.flip()
pygame.time.wait(10)
pygame.quit()