Update points for point scanner, compare different approaches.

points_update.py

import time
import napari
import numpy as np
from napari.qt import thread_worker
from qtpy.QtWidgets import QPushButton, QVBoxLayout, QWidget


# Point property for MALDI points
PROPNAME_ACQUIRED = "acquired"

#
# breaks down
#def generate_maldi_points(nx=500, ny=100, dx=20, dy=20):
def generate_point_grid(nx=10000, ny=150, dx=20, dy=20):
    yy, xx = np.meshgrid(np.arange(ny) * dy, np.arange(nx) * dx)
    points = np.vstack([yy.ravel(), xx.ravel()]).T
    return points


viewer=napari.Viewer()

points = generate_point_grid()    
props = {PROPNAME_ACQUIRED: [False] * len(points)}
pts_layer = viewer.add_points(
    data=points,
    properties=props,
    face_color=PROPNAME_ACQUIRED,
    edge_color=PROPNAME_ACQUIRED,
    face_color_cycle=["yellow", "blue"],
    size=10,
    name="Point Scanner",)

acquired_pts_layer = viewer.add_points(
    face_color='red',
    size=10,
    name="Scanned Points",)


shown = [False] * len(points)
unhide_pts_layer = viewer.add_points(
    data=points,
    face_color='green',
    size=10,
    name="Scanned Points",
    shown=shown)


def change_point_property(point_index):
    propertties=pts_layer.properties
    propertties[PROPNAME_ACQUIRED][point_index] = True
    pts_layer.properties = propertties
    pts_layer.face_color=PROPNAME_ACQUIRED

def add_points(point_index):
    # to allow a fair comparison we work backwards,
    # otherwise we would only start with addding 
    # a few points which would of course be faster
    # (we would only notice a slowdown after a whhile)
    acquired_pts_layer.data  = points[:-point_index]

def show_points(point_index):
    shown[point_index] = True
    unhide_pts_layer.shown=shown

@thread_worker(connect={'yielded': change_point_property})
def recolor_thread(*_):
    for i in range(len(pts_layer.data)):
        time.sleep(0.05) # 20 fps
        yield i
    return

@thread_worker(connect={'yielded': add_points})
def points_in_new_layer_thread(*_):
    for i in range(len(pts_layer.data)):
        time.sleep(0.05) # 20 fps
        yield i
    return


@thread_worker(connect={'yielded': show_points})
def show_points_thread(*_):
    shown = [False] * len(points)
    unhide_pts_layer.shown = shown
    for i in range(len(pts_layer.data)):
        time.sleep(0.05) # 20 fps
        yield i
    return

button_layout = QVBoxLayout()
recolor_btn = QPushButton("Recolor")
recolor_btn.clicked.connect(recolor_thread)
button_layout.addWidget(recolor_btn)

add_pts_btn = QPushButton("AddPts")
add_pts_btn.clicked.connect(points_in_new_layer_thread)
button_layout.addWidget(add_pts_btn)

show_pts_btn = QPushButton("ShowPts")
show_pts_btn.clicked.connect(show_points_thread)
button_layout.addWidget(show_pts_btn)


_widget = QWidget()
_widget.setLayout(button_layout)
_widget.setObjectName("Threading Examples")
viewer.window.add_dock_widget(_widget, allowed_areas=["right"])

if __name__ == '__main__':
    napari.run()