glOrtho 不起作用它仍然被映射到默认坐标

Question

所以我在 python 中使用 pyopengl 来使用 opengl 但是当我在我的重塑函数中使用 glOrtho 来映射我的坐标时它不起作用它仍然被映射到 -1 - 1 这是我的代码：

from OpenGL.GLUT import *
from OpenGL.GL import *

width, height = 500,500

def rectangle(x, y, width, height, color, fill):
    if fill:
        glBegin(GL_POLYGON)
        glColor3ub(color[0], color[1], color[2])
        glVertex2f(x - width/2, y + height/2)
        glVertex2f(x + width/2, y + height/2)
        glVertex2f(x + width/2, y - height/2)
        glVertex2f(x - width/2, y - height/2)
        glColor3ub(255, 255, 255)
        glEnd()
    else:
        glBegin(GL_LINES)
        glColor3ub(color[0], color[1], color[2])
        glVertex2f(x - width/2, y + height/2)
        glVertex2f(x + width/2, y + height/2)
        glVertex2f(x + width/2, y - height/2)
        glVertex2f(x - width/2, y - height/2)
        glColor3ub(255, 255, 255)
        glEnd()

def draw():
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT)
    glClearColor(0.25, 0.25, 0.25, 1)
    glLoadIdentity()

    glBegin(GL_POLYGON)
    glVertex2f(1, 1)
    glVertex2f(-1, 1)
    glVertex2f(-1, -1)
    glVertex2f(100, -1)
    glEnd()

    glutSwapBuffers()


def reshape(w, h):
    glMatrixMode(GL_PROJECTION)
    glLoadIdentity()
    glOrtho(0, w, 0, h, 0, 1000)


glutInit()
glutInitDisplayMode(GLUT_RGBA) # Set the display mode to be colored
glutInitWindowSize(width, height)   # Set the w and h of your window
glutInitWindowPosition(0, 0)   # Set the position at which this windows should appear
window = glutCreateWindow("OpenGL") # Set a window title
glutReshapeFunc(reshape)
glutDisplayFunc(draw) # defines display func
glutIdleFunc(draw) # Keeps the window open
glutMainLoop()  # Keeps the above created window displaying/running in a loop

帮我解决这个问题，我看不出它不起作用的原因

Answer 1

glOrtho 不起作用，因为在 draw 函数的 glLoadIdentity() 指令中。 glLoadIdentity() 加载 Identity matrix. Change the matrix mode after glOrtho with glMatrixMode。这确保了投影矩阵被保留，但单位矩阵被加载到模型视图矩阵中。 OpenGL 是一个状态引擎。一旦状态被改变，它会一直保留直到再次改变，甚至超出帧。

def reshape(w, h):
    glMatrixMode(GL_PROJECTION)
    glLoadIdentity()
    glOrtho(0, w, 0, h, 0, 1000)
    glMatrixMode(GL_MODELVIEW)

glOrtho 不起作用它仍然被映射到默认坐标

glOrtho doesent work it still gets mapped to default coordinates

python

opengl

pyopengl

opengl-compat