python - 使用draw()而不是eventloop时的pyglet

Question

我正在尝试用 pyglet 画一个圆。但当我使用 draw() 函数而不是 app.run() 循环时，它是不可见的。有什么建议我可以做什么吗？谢谢

from math import *
from pyglet.gl import *

window = pyglet.window.Window()

def makeCircle(x_pos, y_pos, radius, numPoints):
    verts = []
    glClear(pyglet.gl.GL_COLOR_BUFFER_BIT)
    glColor3f(1,1,0)
    for i in range(numPoints):
        angle = radians(float(i)/numPoints * 360.0)
        x = radius *cos(angle) + x_pos
        y = radius *sin(angle) + y_pos
        verts += [x,y]
    circle = pyglet.graphics.vertex_list(numPoints, ('v2f', verts))
    circle.draw(GL_LINE_LOOP)
    input()

makeCircle(5,5, 100, 10)

Answer 1

您必须调用window.flip()更新窗口。

由于您没有设置投影矩阵，因此必须在标准化设备坐标中绘制几何图形，所有 3 个分量 (x, y, z) 的范围都在 [-1, 1] 范围内。请注意，当通过 pyglet.app.run() 启动应用程序时，pyglet 默认设置投影矩阵。

调用window.flip()并更改几何形状:

from math import *
from pyglet.gl import *

window = pyglet.window.Window()

def makeCircle(x_pos, y_pos, radius, numPoints):
    verts = []
    glClear(pyglet.gl.GL_COLOR_BUFFER_BIT)
    glColor3f(1,1,0)
    for i in range(numPoints):
        angle = radians(float(i)/numPoints * 360.0)
        x = radius *cos(angle) + x_pos
        y = radius *sin(angle) + y_pos
        verts += [x,y]
    circle = pyglet.graphics.vertex_list(numPoints, ('v2f', verts))
    circle.draw(GL_LINE_LOOP)

    window.flip()           # <--------

    input()

makeCircle(0, 0, 0.5, 10)   # <--------

<小时/>

或者，您可以自己设置正交投影，通过 glOrtho 。例如:

from math import *
from pyglet.gl import *

window = pyglet.window.Window()

def makeCircle(x_pos, y_pos, radius, numPoints):
    verts = []

    glMatrixMode(GL_PROJECTION)
    glOrtho(0, 640, 0, 480, -1, 1)
    glMatrixMode(GL_MODELVIEW)

    glClear(pyglet.gl.GL_COLOR_BUFFER_BIT)
    glColor3f(1,1,0)
    for i in range(numPoints):
        angle = radians(float(i)/numPoints * 360.0)
        x = radius *cos(angle) + x_pos
        y = radius *sin(angle) + y_pos
        verts += [x,y]
    circle = pyglet.graphics.vertex_list(numPoints, ('v2f', verts))
    circle.draw(GL_LINE_LOOP)

    text = 'This is a test but it is not visible'
    label = pyglet.text.Label(text, font_size=36,
                          x=10, y=10, anchor_x='left', anchor_y='bottom',
                          color=(255, 123, 255, 255))
    label.draw()

    window.flip()
    input()

makeCircle(5,5, 100, 10)