1

I am using Vispy to rotate a cube. I can use imageio to use a custom texture in the face of the rotating cube successfully, but I don't understand how to use a movie or gif image.

Full source code:

import numpy as np

from vispy import gloo, app
from vispy.gloo import Program, VertexBuffer, IndexBuffer
from vispy.util.transforms import perspective, translate, rotate
from vispy.geometry import create_cube
import imageio

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


vertex = """
uniform mat4 model;
uniform mat4 view;
uniform mat4 projection;
uniform sampler2D texture;

attribute vec3 position;
attribute vec2 texcoord;
attribute vec3 normal;
attribute vec4 color;

varying vec2 v_texcoord;
void main()
{
    gl_Position = projection * view * model * vec4(position,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=(750, 750), title='Textured cube',
                            keys='interactive')
        self.timer = app.Timer('auto', self.on_timer)

        # Build cube data
        V, I, _ = create_cube()
        vertices = VertexBuffer(V)
        self.indices = IndexBuffer(I)

        # Build program
        self.program = Program(vertex, fragment)
        self.program.bind(vertices)

        # Build view, model, projection & normal
        view = translate((0, 0, -5))
        model = np.eye(4, dtype=np.float32)
        self.program['model'] = model
        self.program['view'] = view
        self.program['texture'] = im # checkerboard()

        self.activate_zoom()

        self.phi, self.theta = 0, 0

        # OpenGL initalization
        gloo.set_state(clear_color=(0.30, 0.30, 0.35, 1.00), depth_test=True)
        self.timer.start()

        self.show()

    def on_draw(self, event):
        gloo.clear(color=True, depth=True)
        self.program.draw('triangles', self.indices)

    def on_resize(self, event):
        self.activate_zoom()

    def activate_zoom(self):
        gloo.set_viewport(0, 0, *self.physical_size)
        projection = perspective(45.0, self.size[0] / float(self.size[1]),
                                 2.0, 10.0)
        self.program['projection'] = projection

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

if __name__ == '__main__':
    c = Canvas()
    app.run()
genpfault
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Anay Bose
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1 Answers1

1

A gif or a movie is essentially many image frames, coming one after the other.

What you would need to do is read the images from the GIF into an array containing the RGB(A) values of each image (for GIF, you can use the code from e.g. https://gist.github.com/BigglesZX/4016539), and then advance self.program['texture'] to the next frame of the GIF in on_timer.

In case you want to loop the texture, you could use the modulo operator %, so you don't run over the array boundaries, with something like

# gif_array is the array populated with GIF frames
self.program['texture'] = gif_array[index % (len(gif_array) - 1)]
index = index + 1
skalarproduktraum
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