And with
self.program['position'] = newPosI get the following error :
File "testVispy.py", line 34, in on_timer
self.program['position'] = newPos
File "/home/chams/.local/lib/python3.6/site-packages/vispy/gloo/program.py", line 409, in __setitem__
vbo.set_data(data)
File "/home/chams/.local/lib/python3.6/site-packages/vispy/gloo/buffer.py", line 381, in set_data
raise RuntimeError("Cannot set data on buffer view.")
RuntimeError: Cannot set data on buffer view.
@cgharib This is definitely a surprise to me, but I don't have the historic context for why it is this way. A workaround is to reuse a VertexBuffer (or other buffer type) yourself, update the data, then reset that buffer. Like this with
_pos:class MyCanvas(app.Canvas):
def __init__(self):
app.Canvas.__init__(self)
self.program = gloo.Program(vertex, fragment, count=2)
self._pos = gloo.VertexBuffer()
self.program['position'] = np.array([[.5, 0], [-.5, 0]], dtype=np.float32)
self.timer = app.Timer("auto", self.on_timer)
self.timer.start()
self.show()
def on_timer(self, event):
totalTime = self.timer.elapsed
x = .5*np.cos(totalTime)
newPos = np.array([(x, 0), (-x, 0)])
self._pos.set_data(newPos.astype(np.float32))
self.program['position'] = self._pos
self.update()@almarklein @rougier Any memory why gloo.Program creates a View for each of the buffers? Meaning self.program['position'] is a DataBufferView when the program is created?
@cgharib Actually if you set the VertexBuffer in the __init__ and then do self.program['position'] = newPos.astype(np.float32) then it seems to work. The main problem seems to be that the gloo.Program creation defaults to creating a View. I'm not exactly sure why the original self.program['position'] = works as that should be a View too.
Hey. Thanks for all your answers. So here's how I would write it based on @djhoese 's code.
import numpy as np
from vispy import app, gloo
vertex = """
attribute vec2 position;
void main() {
gl_Position = vec4(position, 0., 1.);
}
"""
fragment = """
void main() {
gl_FragColor = vec4(1.,0.,0.,1.);
}
"""
class MyCanvas(app.Canvas):
def __init__(self):
app.Canvas.__init__(self)
self.program = gloo.Program(vertex, fragment, count=2)
self.vertexBuffer = gloo.VertexBuffer(np.array([(.5, 0), (-.5, 0)], dtype=np.float32))
self.program['position'] = self.vertexBuffer
self.timer = app.Timer('auto', self.on_timer)
self.timer.start()
self.show()
def on_draw(self, event):
gloo.clear()
self.program.draw('lines')
def on_timer(self, event):
totalTime = self.timer.elapsed
x = .5*np.cos(totalTime)
newPos = np.array([(x, 0), (-x, 0)], dtype=np.float32)
self.vertexBuffer.set_data(newPos)
self.update()
c = MyCanvas()
app.run()Does it seem idiomatic to you ? Thanks a lot !
@cgharib I personally would change your timer handler to do
self.program['position'] = newPos. It feels more future-proof and avoids the possibility of the VertexBuffer being copied inside the Program and your set_data not having an effect. Hopefully that makes sense. Either way should work so do what feels good to you.
Hello all, I am trying to specify a z position of an EllipseVisual's center so that I can layer it on image visuals, but it seems as if that is not allowed as only the first 2 elements of the passed center are used to create the vertices of the ellipse. Is there something I am missing or does this require an edit?
@tjjdoman_gitlab It looks like you are right that the center point is only 2D. You could try using an STTransform to force the Z position by doing
ellipse.transform = STTransform(translate=(0, 0, some_z_shift)). You may also run into issues with drawing order between the Image and Ellipse where you may need to do something like ellipse.order = -5, but see if the Z position works well enough first.
@djhoese I'm using the turntable camera with the vispy.scene. I have a bunch of points in 3d space, and would like to have the camera rotate around its center of mass instead of the origin point
Hello guys. I'm developing a software to visualize thickness maps by using PyQt as Desktop Framework, however, I'm experiencing some problems. The central widget is a grid layout with multiple scatter plots, in a sub grid each, When i minimize and maximize the window multiple times the layout tends to collapse, then i get the following error
WARNING: Traceback (most recent call last):
File ".\src\CrushingApp.py", line 324, in <module>
sys.exit(app.exec_())
File "C:\Users\site-packages\vispy\app\backends\_qt.py", line 508, in event
out = super(QtBaseCanvasBackend, self).event(ev)
File "C:\Users\site-packages\vispy\app\backends\_qt.py", line 825, in paintGL
self._vispy_canvas.events.draw(region=None)
File "C:\Users\\site-packages\vispy\util\event.py", line 455, in __call__
self._invoke_callback(cb, event)
File "C:\Users\site-packages\vispy\util\event.py", line 475, in _invoke_callback
self, cb_event=(cb, event))
<< caught exception here: >>
File "C:\Users\site-packages\vispy\util\event.py", line 471, in _invoke_callback
cb(event)
File "C:\Users\site-packages\vispy\scene\canvas.py", line 217, in on_draw
self._draw_scene()
File "C:\Users\site-packages\vispy\scene\canvas.py", line 266, in _draw_scene
self.draw_visual(self.scene)
File "C:\Users\site-packages\vispy\scene\canvas.py", line 304, in draw_visual
self.add_with_artificial_variable(expr)
File "C:\Users\site-packages\vispy\ext\_bundled\cassowary\simplex_solver.py", line 381, in
add_with_artificial_variable
raise RequiredFailure()
vispy.ext._bundled.cassowary.error.RequiredFailure
ERROR: Invoking <bound method SceneCanvas.on_draw of <CanvasMapaEspesores (PyQt5) at 0x149ed69fe08>> for DrawEventis there a way to avoi
avoid/fix* this
sometimes collapse the entire layout
Now i got the last version and It is working as expected by the moment. Now i have another problem. I need to put some annotations in a view with a turntable camera, I'm using vispy.scene.visuals.Text which is a 2D Text which follows the camera rotation, i would like to set a background and i tried by creating a plane, set transform properties then copy the rotation of the camera, but the roll angle is not working on turntable. Is there another way to set a background rectangle for a vispy.scene.visuals.Text?
this is that i want
self.t2 = scene.visuals.Text('Test Text', parent=self.view.scene, color='green')
self.t2.font_size = 14
self.plane = scene.visuals.Plane(
width=1000,
height=300,
parent=self.t2
)
self.plane.transform = vispy.visuals.transforms.STTransform(translate=(0, 0, 0),
scale=(1., 1., 1.)).as_matrix()
def on_mouse_move(self, event):
if event.button == 1 and event.is_dragging:
self.plane.transform.reset()
self.plane.transform.rotate(self.view.camera.azimuth, (0, 0, 1))
self.plane.transform.rotate(90 - self.view.camera.elevation, (0, 1, 0))
self.plane.transform.rotate(self.view.camera.roll, (1, 0, 0))
in the code of vispy the roll camera angle appears as 'not implemented' :(
I understand what you're going for. I just don't understand what is going wrong. I don't have a lot of experience with the TurntableCamera but if you could provide me an end to end example (a small example that I can copy/paste and run locally) then I might have some ideas. So far I'm not really sure exactly how it is wrong since I haven't played with it myself
import numpy as np
import vispy.scene
from vispy.scene import visuals
from vispy.visuals import text
class CustomCanvas(vispy.scene.SceneCanvas):
def __init__(self):
super(CustomCanvas, self).__init__(keys='interactive', show=True)
self.unfreeze()
self.view = self.central_widget.add_view()
self.xyz_top = None
self.textLabelMax = None
self.backgroundLabelMax = None
self.events.mouse_move.connect(self.on_mouse_move)
self.freeze()
def on_mouse_move(self, event):
if(event.button == 1 and event.is_dragging):
self.backgroundLabelMax.transform.reset()
self.backgroundLabelMax.transform.rotate(self.view.camera.azimuth, (0, 0, 1))
self.backgroundLabelMax.transform.rotate(90 - self.view.camera.elevation, (1, 0, 0))
self.backgroundLabelMax.transform.translate(self.xyz_top)
def draw_cloud_points(self):
pos = np.random.normal(size=(100000, 3), scale=0.2)
# one could stop here for the data generation, the rest is just to make the
# data look more interesting. Copied over from magnify.py
centers = np.random.normal(size=(50, 3))
indexes = np.random.normal(size=100000, loc=centers.shape[0]/2.,
scale=centers.shape[0]/3.)
indexes = np.clip(indexes, 0, centers.shape[0]-1).astype(int)
scales = 10**(np.linspace(-2, 0.5, centers.shape[0]))[indexes][:, np.newaxis]
pos *= scales
pos += centers[indexes]
# create scatter object and fill in the data
scatter = visuals.Markers()
scatter.set_data(pos, edge_color=None, face_color=(1, 1, 1, .5), size=5)
self.view.add(scatter)
# Adding text label at center / top (Z axis)
self.xyz_top = (pos[:,0].max(), pos[:,1].max(), pos[:,2].max())
self.textLabelMax = visuals.Text(pos=self.xyz_top, text="Test_Label_Max", font_size=24, color="white", parent=self.view.scene)
# Adding plane as background for texts
self.backgroundLabelMax = visuals.Plane(width=5, height = 1, color=(1, 0, 0, 0.4), parent=self.view.scene)
self.backgroundLabelMax.transform = vispy.scene.transforms.STTransform(
scale=(1, 1, 1),
translate=self.xyz_top
).as_matrix()
# Adding turntable with ortographic view
self.view.camera = vispy.scene.TurntableCamera(fov=0, azimuth=0, elevation=90, roll=0)
# Auto focus
self.view.camera.set_range()
def main():
custom_canvas = CustomCanvas()
custom_canvas.draw_cloud_points()
if __name__ == '__main__':
import sys
if sys.flags.interactive != 1:
main()
vispy.app.run()
I based this on this example https://vispy.org/gallery/scene/point_cloud.html#sphx-glr-gallery-scene-point-cloud-py
I'll try to find time to look into this more today or sometime this week
Surprisingly doing
self.backgroundLabelMax.transform.matrix = self.view.camera.transform.matrix and self.backgroundLabelMax.transform.translate(self.xyz_top) gets it pretty close...somehow
Now it's working. I think this is very usefull when u want to visualize annotations over 3D things
import numpy as np
import vispy.scene
from vispy.scene import visuals
from vispy.visuals import text
class CustomCanvas(vispy.scene.SceneCanvas):
def __init__(self):
super(CustomCanvas, self).__init__(keys='interactive', show=True)
self.unfreeze()
self.view = self.central_widget.add_view()
self.xyz_top = None
self.textLabelMax = None
self.backgroundLabelMax = None
self.bgScale = [1, 1, 1]
self.events.mouse_move.connect(self.on_mouse_move)
self.events.mouse_wheel.connect(self.on_mouse_wheel)
self.freeze()
def on_mouse_move(self, event):
if(event.button == 1 and event.is_dragging):
self.backgroundLabelMax.transform.reset()
self.backgroundLabelMax.transform.matrix = self.view.camera.transform.matrix
self.backgroundLabelMax.transform.translate(self.xyz_top)
def on_mouse_wheel(self, event):
pass
"""
self.backgroundLabelMax.transform.reset()
delta = event.delta[1]
if(delta < 0):
print(delta)
if self.view.camera.scale_factor >= 30:
self.view.camera.scale_factor = 30
else:
if self.view.camera.scale_factor <= 10:
self.view.camera.scale_factor = 10
self.backgroundLabelMax.transform.matrix = self.view.camera.transform.matrix
self.backgroundLabelMax.transform.scale(self.bgScale)
self.backgroundLabelMax.transform.translate(self.xyz_top)
"""
def draw_cloud_points(self):
pos = np.random.normal(size=(100000, 3), scale=0.2)
# one could stop here for the data generation, the rest is just to make the
# data look more interesting. Copied over from magnify.py
centers = np.random.normal(size=(50, 3))
indexes = np.random.normal(size=100000, loc=centers.shape[0]/2.,
scale=centers.shape[0]/3.)
indexes = np.clip(indexes, 0, centers.shape[0]-1).astype(int)
scales = 10**(np.linspace(-2, 0.5, centers.shape[0]))[indexes][:, np.newaxis]
pos *= scales
pos += centers[indexes]
# create scatter object and fill in the data
scatter = visuals.Markers()
scatter.set_data(pos, edge_color=None, face_color=(1, 1, 1, .5), size=5)
self.view.add(scatter)
# Adding turntable with ortographic view
self.view.camera = vispy.scene.TurntableCamera(fov=0)
# Adding plane as background for texts
self.backgroundLabelMax = visuals.Rectangle(center = (0, 0, 0), width=3.5, height = 1, color=(1, 0, 0, 0.4), radius=0.3, parent=self.view.scene)
# Adding text label at center / top (Z axis)
self.xyz_top = (pos[:,0].max(), pos[:,1].max(), pos[:,2].max())
self.textLabelMax = visuals.Text(pos=(0, 0, 0), text="Test_Label_Max", font_size=18, color="white", parent=self.backgroundLabelMax)
self.backgroundLabelMax.transform = vispy.scene.transforms.STTransform(
scale=(1, 1, 1),
translate=(0, 0, 0)
).as_matrix()
self.backgroundLabelMax.transform.matrix = self.view.camera.transform.matrix
self.backgroundLabelMax.transform.translate(self.xyz_top)
# Auto focus
self.view.camera.set_range()
def main():
custom_canvas = CustomCanvas()
custom_canvas.draw_cloud_points()
if __name__ == '__main__':
import sys
if sys.flags.interactive != 1:
main()
vispy.app.run()
Looking at the README in that directory, that command is probably out dated. It should be as "easy" as running
make html in the docdirectory. Note however that by default it will run all of the gallery examples which can take a long time. There is a way to make it not do that but I don't remember off the top of my head
@djhoese Really I'm just looking for documentation to read and it seems sparse. I stumbled on that folder in the repo and thought I had to build the docs myself to get documentation I can learn from. Where would you say the best docs to learn vispy are? I also noticed multiple blogs and wiki's on the website are linked but the links are dead.
