py: add cam.py

diff --git a/py/cam.py b/py/cam.py
new file mode 100755 (executable)
index 0000000..b44f8f9
--- /dev/null
+++ b/py/cam.py
@@ -0,0 +1,78 @@
+#!/usr/bin/python3
+
+import sys
+import selectors
+import pykms
+from helpers import *
+
+
+w = 640
+h = 480
+fmt = pykms.PixelFormat.YUYV
+
+
+# This hack makes drm initialize the fbcon, setting up the default connector
+card = pykms.Card()
+card = 0
+
+card = pykms.Card()
+res = pykms.ResourceManager(card)
+conn = res.reserve_connector()
+crtc = res.reserve_crtc(conn)
+plane = res.reserve_overlay_plane(crtc, fmt)
+
+mode = conn.get_default_mode()
+
+NUM_BUFS = 5
+
+fbs = []
+for i in range(NUM_BUFS):
+    fb = pykms.DumbFramebuffer(card, w, h, fmt)
+    fbs.append(fb)
+
+vidpath = pykms.VideoDevice.get_capture_devices()[0]
+
+vid = pykms.VideoDevice(vidpath)
+cap = vid.capture_streamer
+cap.set_port(0)
+cap.set_format(fmt, w, h)
+cap.set_queue_size(NUM_BUFS)
+
+for fb in fbs:
+    cap.queue(fb)
+
+cap.stream_on()
+
+
+def readvid(conn, mask):
+    fb = cap.dequeue()
+
+    if card.has_atomic:
+        set_props(plane, {
+            "FB_ID": fb.id,
+            "CRTC_ID": crtc.id,
+            "SRC_W": fb.width << 16,
+            "SRC_H": fb.height << 16,
+            "CRTC_W": fb.width,
+            "CRTC_H": fb.height,
+        })
+    else:
+        crtc.set_plane(plane, fb, 0, 0, fb.width, fb.height,
+            0, 0, fb.width, fb.height)
+
+    cap.queue(fb)
+
+def readkey(conn, mask):
+    #print("KEY EVENT");
+    sys.stdin.readline()
+    exit(0)
+
+sel = selectors.DefaultSelector()
+sel.register(cap.fd, selectors.EVENT_READ, readvid)
+sel.register(sys.stdin, selectors.EVENT_READ, readkey)
+
+while True:
+    events = sel.select()
+    for key, mask in events:
+        callback = key.data
+        callback(key.fileobj, mask)