1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
|
function res = CV1Test(useRTbox)
% res = CV1Test([useRTbox=0]) - A timing test script for HMDs by use of a photometer.
%
% Needs the RTBox, and a photo-diode or such, e.g., a ColorCal-II,
% connected to the TTL trigger input.
%
% Atm., we still measure a discrepancy of about 75 msecs between what
% 'Flip' reports according to our drivers timestamping, and what the
% photometer based timestamping reports. That's still not good enough, and
% i'm out of ideas on how to improve this.
%
% Onset scheduling also becomes erratic for short waitframes intervals
% between white flashes.
%
if nargin < 1 || isempty(useRTbox)
useRTbox = 0;
end
waitframes = 90;
% Setup unified keymapping and unit color range:
PsychDefaultSetup(2);
% Select screen with highest id as Oculus output display:
screenid = max(Screen('Screens'));
%PsychDebugWindowConfiguration([],0.75);
% Open our fullscreen onscreen window with black background clear color:
PsychImaging('PrepareConfiguration');
% Setup the HMD to act as a regular "monoscopic" display monitor
% by displaying the same image to both eyes:
% PsychDebugWindowConfiguration; hmd = PsychVRHMD('AutoSetupHMD', 'Monoscopic', 'HUD=0 DebugDisplay');
hmd = PsychVRHMD('AutoSetupHMD', 'Monoscopic');
PsychOculusVR1('Verbosity', 3);
Screen('Preference','Verbosity', 3);
[win, rect] = PsychImaging('OpenWindow', screenid);
ifi = Screen('GetFlipInterval', win);
% Render one view for each eye in stereoscopic mode, in an animation loop:
res.vbl = [];
res.failFlag = [];
res.tBase = [];
res.measuredTime = [];
if useRTbox
rtbox = PsychRTBox('Open'); %, 'COM5');
% Query and print all box settings inside the returned struct 'boxinfo':
res.boxinfo = PsychRTBox('BoxInfo', rtbox);
disp(res.boxinfo);
% Enable photo-diode and TTL trigger input of box, and only those:
PsychRTBox('Disable', rtbox, 'all');
PsychRTBox('Enable', rtbox, 'pulse');
WaitSecs(1);
% Clear receive buffers to start clean:
PsychRTBox('Stop', rtbox);
PsychRTBox('Clear', rtbox);
PsychRTBox('Start', rtbox);
if ~IsWin
% Hack: Enable async background reads to speedup box operations:
IOPort ('ConfigureSerialport', res.boxinfo.handle, 'BlockingBackgroundRead=1 StartBackgroundRead=1');
end
end
while ~KbCheck
Screen('FillRect', win, 0);
tBase = Screen('Flip', win);
%Screen('Flip', win);
%tBase = WaitSecs(0.5);
res.tBase(end+1) = tBase;
Screen('FillRect', win, 1);
res.vbl(end+1) = Screen('Flip', win, tBase + (waitframes - 0.5) * ifi);
% Measure real onset time:
if useRTbox
% Fetch sample immediately to preserve correspondence:
[time, event, mytstamp] = PsychRTBox('GetSecs', rtbox)
if isempty(mytstamp)
% Failed within expected time window. This probably due to
% tearing artifacts or GPU malfunction. Mark it as "tearing"
% and retry for 1 full more video refresh:
res.failFlag(end+1) = 1;
[time, event, mytstamp] = PsychRTBox('GetSecs', rtbox);
if isempty(mytstamp)
% Ok, this is fucked up. No way to recover :-(
res.failFlag(end) = 2;
res.measuredTime(end+1) = nan;
else
% Got something:
res.measuredTime(end+1) = max(mytstamp);
end
else
% Success!
res.failFlag(end+1) = 0;
res.measuredTime(end+1) = max(mytstamp);
end
if ~isempty(time)
fprintf('DT Flip %f msecs. Box uncorrected %f msecs.\n', 1000 * (res.vbl(end) - res.tBase(end)), 1000 * (max(time) - res.tBase(end)));
end
else
fprintf('DT Flip %f msecs.\n', 1000 * (res.vbl(end) - res.tBase(end)));
end
end
% Backup save for safety:
save('OculusTimingResults.mat', 'res', '-V6');
sca;
close all;
figure;
if useRTbox
PsychRTBox('Stop', rtbox);
PsychRTBox('Clear', rtbox);
if ~IsWin
% Hack: Disable async background reads:
fprintf('Stopping background read op on box...\n');
IOPort ('ConfigureSerialport', res.boxinfo.handle, 'StopBackgroundRead');
IOPort ('ConfigureSerialport', res.boxinfo.handle, 'BlockingBackgroundRead=0');
fprintf('...done, now remapping timestamps.\n');
end
% Primary save for safety:
save('OculusTimingResults.mat', 'res', '-V6');
% Remap box timestamps to GetSecs timestamps:
res.measuredTime = PsychRTBox('BoxsecsToGetsecs', rtbox, res.measuredTime);
fprintf('...done, saving backup copy of data, then closing box.\n');
plot(1:length(res.vbl), 1000 * (res.vbl - res.tBase), 1:length(res.measuredTime), 1000 * (res.measuredTime - res.tBase));
% Close connection to box:
PsychRTBox('CloseAll');
dT = res.measuredTime - res.vbl;
dT = dT(~isnan(dT));
dT = 1000 * mean(dT);
ifi = ifi * 1000;
fprintf('Mean difference Measurement - Flip: %f msecs [-half refresh: %f msecs], frames %f\n', dT, dT - ifi / 2, (dT - ifi / 2) / ifi);
else
plot(1:length(res.vbl), 1000 * (res.vbl - res.tBase));
end
title('Corrected data [msecs]:');
|
