Question

我正在尝试使用Vispy在3d中旋转纹理四边形，但我似乎无法解决它。代码不会产生任何特定的错误，但它根本不会旋转。我是Vispy的新手，也许我在代码中缺少一些重要的组件。也许你们中的一些人之前已经解决了类似的问给我一些见解将有很大帮助。这是代码：

import numpy as np

from vispy import gloo, app
app.use_app('pyqt5')
from vispy.gloo import Program
from vispy.util.transforms import perspective, translate, rotate
import imageio


im = imageio.imread('C:\\vhosts\\VIDEO_TWO_CLONE\\fol1\\im.jpg')


vertex = """
    uniform   mat4 u_model;
    attribute vec2 position;
    attribute vec2 texcoord;
    varying vec2 v_texcoord;
    void main()
    {
        gl_Position = u_model * vec4(position, 0.0, 1.0);
        v_texcoord = texcoord;
    } """

fragment = """
    uniform sampler2D texture;
    varying vec2 v_texcoord;
    void main()
    {
        gl_FragColor = texture2D(texture, v_texcoord);
    } """


def checkerboard(grid_num=8, grid_size=32):
    row_even = grid_num // 2 * [0, 1]
    row_odd = grid_num // 2 * [1, 0]
    Z = np.row_stack(grid_num // 2 * (row_even, row_odd)).astype(np.uint8)
    return 255 * Z.repeat(grid_size, axis=0).repeat(grid_size, axis=1)


class Canvas(app.Canvas):
    def __init__(self):
        app.Canvas.__init__(self, size=(512, 512), title='Textured quad',
                            keys='interactive')

        self.model = np.eye(4, dtype=np.float32)
        # Build program & data
        self.program = Program(vertex, fragment, count=4)
        self.program['position'] = [(1, 1), (-1, 1),
                                    (1, -1), (-1, -1)]
        self.program['texcoord'] = [(0, 0), (1, 0), (0, 1), (1, 1)]
        self.program['texture'] = im # checkerboard()
        self.program['u_model'] = self.model



        self.theta = 0
        self.phi = 0


        gloo.set_viewport(0, 0, *self.physical_size)

        self.show()

    def on_draw(self, event):
        gloo.set_clear_color('white')
        gloo.clear(color=True)
        self.program.draw('triangle_strip')


    def on_timer(self, event):
        self.theta += .5
        self.phi += .5
        self.model = np.dot(rotate(self.theta, (0, 1, 0)),
                            rotate(self.phi, (0, 0, 1)))
        self.program['u_model'] = self.model
        self.update()


    def on_resize(self, event):
        gloo.set_viewport(0, 0, *event.physical_size)

if __name__ == '__main__':
    c = Canvas()
    app.run()

Answer 1

矩阵均匀model，它定义了模型的位置和旋转在方法on_timer中设置。每次执行on_timer时，模型矩阵都会更改，会旋转模型。但似乎计时器永远不会启动，on_timer永远不会被执行。

要启动计时器，您必须在初始化期间调用app.Timer。在类Canvas的构造函数中添加类似于以下代码的内容：

class Canvas(app.Canvas):
    def __init__(self):
        app.Canvas.__init__(self, size=(512, 512), title='Textured quad', keys='interactive')

        .......

        self._timer = app.Timer('auto', connect=self.on_timer, start=True)

另见vispy/examples/tutorial/app/interactive.py

尝试使用Vispy在3d中旋转四边形

1 个答案: