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@FoamyGuy
Created March 14, 2025 19:26
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#!/usr/bin/python3
"""
Display a (possibly scaled) X session to a matrix
The display runs until the graphical program exits.
The display doesn't get a keyboard or mouse, so you have to use a program that
will get its input in some other way, such as from a gamepad.
For help with commandline arguments, run `python virtualdisplay.py --help`
This needs additional software to be installed (besides a graphical program to run). At a minimum you have to
install a virtual display server program (xvfb) and the pyvirtualdisplay importable Python module:
$ sudo apt install -y xvfb
$ pip install pyvirtualdisplay
Here's an example for running an emulator using a rom stored in "/tmp/snesrom.smc" on a virtual 128x128 panel made from 4 64x64 panels:
$ python virtualdisplay.py --pinout AdafruitMatrixHatBGR --scale 2 --backend xvfb --width 128 --height 128 --serpentine --num-address-lines 5 --num-planes 4 -- mednafen -snes.xscalefs 1 -snes.yscalefs 1 -snes.xres 128 -video.fs 1 -video.driver softfb /tmp/snesrom.smc
"""
import shlex
from subprocess import Popen
import contextlib
import click
import numpy as np
from PIL import ImageEnhance
from pyvirtualdisplay.smartdisplay import SmartDisplay
import adafruit_blinka_raspberry_pi5_piomatter as piomatter
import adafruit_blinka_raspberry_pi5_piomatter.click as piomatter_click
from adafruit_blinka_raspberry_pi5_piomatter.pixelmappers import simple_multilane_mapper
@contextlib.contextmanager
def TerminatingPopen(*args, **kw):
p = Popen(*args, **kw)
try:
yield p
finally:
print("exterminate", p.poll())
p.kill() # The harshest way to end the subprocess
print("exterminated?", p.poll())
@click.command
@click.option("--scale", type=float, help="The scale factor, larger numbers mean more virtual pixels", default=1)
@click.option("--backend", help="The pyvirtualdisplay backend to use", default="xvfb")
@click.option("--extra-args", help="Extra arguments to pass to the backend server", default="")
@click.option("--rfbport", help="The port number for the --backend xvnc", default=None, type=int)
@click.option("--brightness", help="The brightness factor of the image output to the matrix",
default=1.0, type=click.FloatRange(min=0.1, max=1.0))
@click.option("--use-xauth/--no-use-xauth", help="If a Xauthority file should be created", default=False)
@piomatter_click.standard_options
@click.argument("command", nargs=-1)
def main(scale, backend, use_xauth, extra_args, rfbport, brightness, width, height, serpentine, rotation, pinout,
n_planes, n_temporal_planes, n_addr_lines, n_lanes, command):
kwargs = {}
if backend == "xvnc":
kwargs['rfbport'] = rfbport
if extra_args:
kwargs['extra_args'] = shlex.split(extra_args)
print("xauth", use_xauth)
if n_lanes != 2:
pixelmap = simple_multilane_mapper(width, height, n_addr_lines, n_lanes)
geometry = piomatter.Geometry(width=width, height=height, n_planes=n_planes, n_addr_lines=n_addr_lines,
n_temporal_planes=n_temporal_planes, n_lanes=n_lanes, map=pixelmap)
else:
geometry = piomatter.Geometry(width=width, height=height, n_planes=n_planes, n_addr_lines=n_addr_lines,
n_temporal_planes=n_temporal_planes, rotation=rotation)
framebuffer = np.zeros(shape=(geometry.height, geometry.width, 3), dtype=np.uint8)
matrix = piomatter.PioMatter(colorspace=piomatter.Colorspace.RGB888Packed, pinout=pinout, framebuffer=framebuffer, geometry=geometry)
with SmartDisplay(backend=backend, use_xauth=use_xauth, size=(round(width*scale),round(height*scale)), manage_global_env=False, **kwargs) as disp, TerminatingPopen(command, env=disp.env()) as proc:
while proc.poll() is None:
img = disp.grab(autocrop=False)
if img is None:
continue
if brightness != 1.0:
darkener = ImageEnhance.Brightness(img)
img = darkener.enhance(brightness)
img = img.resize((width, height))
framebuffer[:, :] = np.array(img)
matrix.show()
if __name__ == '__main__':
main()
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