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
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
|
% MonoStereoDemo
%
% demonstration of displaying a precalculated texture based movie, whilst
% controlling the FE1 goggles using a Tlock packet.
%
% For use with the OSX version of Psychtoolbox.
% tested with version 1.0.5.
% uses the hidden 'LoadNormalizedGammaTable' screen function.
%
% Please note that this demo as configured needs 256MB system ram.
% It also needs the Bits++ from Cambridge Research Systems!!
% Designed to be used in the "mono++" enhanced monochrome mode.
%
% Sections have been lifted from the OSX movie demo etc.
%
% 26/04/2005 ejw wrote it.
clear; close all
% Define screen
whichScreen=max(Screen('Screens'));
% Find the color values which correspond to white and black. Though on OS
% X we currently only support true color and thus, for scalar color
% arguments,
% black is always 0 and white 255, this rule is not true on other platforms will
% not remain true on OS X after we add other color depth modes.
white=WhiteIndex(whichScreen);
black=BlackIndex(whichScreen);
gray=GrayIndex(whichScreen);
% Open up the a window on the screen.
% This is done by calling the Screen function of the Psychophysics
% Toolbox. We need to open the onscreen window first, so that
% the offscreen storage allocated subsequently is properly
% matched to the onscreen frame buffer.
[window,screenRect] = Screen('OpenWindow',whichScreen,128,[],32,2);
% THE FOLLOWING STEP IS IMPORTANT.
% make sure the graphics card LUT is set to a linear ramp
% (else the encoded data will not be recognised by Bits++).
% There is a bug with the underlying OpenGL function, hence the scaling 0 to 255/256.
% This demo will not work using a default gamma table in the graphics card,
% or even if you set the gamma to 1.0, due to this bug.
% This is NOT a bug with Psychtoolbox!
Screen('LoadNormalizedGammaTable',window,linspace(0,(255/256),256)'*ones(1,3));
% draw a gray background on front and back buffers
Screen('FillRect',window, gray);
Screen('Flip', window);
Screen('FillRect',window, gray);
% =================================================================
% CODE NEEDED HERE !
% "linear_lut" should be replaced here with one giving the inverse
% characteristic of the monitor.
% =================================================================
% restore the Bits++ LUT to a linear ramp
linear_lut = repmat(round(linspace(0, 2^16 -1, 256))', 1, 3);
BitsPlusSetClut(window,linear_lut);
% find out how big the window is
[screenWidth, screenHeight]=Screen('WindowSize', window);
% textures can't seem to be bigger than the screen, though they have to be
% square. So the max texture size is the smaller of the screen dimensions!!
max_texture_size = min([screenWidth screenHeight]);
% pre calculate two counter rotating gratings
% some graphics cards have a hardware texture size limit of 256 square
% (any bigger and it is slow). Be aware that textures use up RAM very quickly.
texture_size=256;
if (max_texture_size < texture_size)
error('screen must have a minimum resolution of 256');
end
image=zeros(texture_size,texture_size,3);
[x,y] = meshgrid(1: texture_size, 1: texture_size);
% number of cycles of sine wave in patch
cycles=10;
for orient=1:180
fprintf('Calculating angle %d\n',orient);
phase=cycles*2*pi*((sin(pi*(orient-1)/180)*(y - texture_size/2)+cos(pi*(orient-1)/180)*(x - texture_size/2)) - 1)/(texture_size/2);
mono=0.5*(2^16)*(sin(phase)+1);
% ==================================================================
% CODE NEEDED HERE !
% "mono" should be corrected here for the inverse characteristic of
% the monitor.
% ==================================================================
image = BitsPlusPackMonoImage(mono);
left(orient)= Screen('MakeTexture',whichScreen,image);
phase=cycles*2*pi*((-sin(pi*(orient-1)/180)*(y - texture_size/2)+cos(pi*(orient-1)/180)*(x - texture_size/2)) - 1)/(texture_size/2);
mono=0.5*(2^16)*(sin(phase)+1);
% ==================================================================
% CODE NEEDED HERE !
% "mono" should be corrected here for the inverse characteristic of
% the monitor.
% ==================================================================
image = BitsPlusPackMonoImage(mono);
right(orient)= Screen('MakeTexture',whichScreen,image);
end
% now quickly display the previously calculated textures,
% add in the control for the goggles
fprintf('Displaying counter-rotating gratings, hold a key to exit \n');
while(~KbCheck)
for orient= 1:180
Screen('DrawTexture',window,left(orient));
% bitsgoggles adds the one line image to control the digital o/p
% then calls 'Flip'
% Note that bitsGoggles controls the goggle state for the frame
% >after< it is displayed, hence we set the right goggle open now
bitsGoggles(1,0,window);
Screen('DrawTexture',window,right(orient));
% bitsgoggles adds the one line image to control the digital o/p
% then calls 'Flip'
% Note that bitsGoggles controls the goggle state for the frame
% >after< it is displayed, hence we set the left goggle open now
bitsGoggles(0,1,window);
end
end
% reset the digital output data
Mask=0;
Command=0;
Data=zeros(1,248);
bitsEncodeDIO(Mask,Data,Command, window);
% if the system only has one screen, set the LUT in Bits++ to a linear ramp
% if the system has two or more screens, then blank the screen.
if (whichScreen == 0)
% =================================================================
% CODE NEEDED HERE !
% "linear_lut" should be replaced here with one giving the inverse
% characteristic of the monitor.
% =================================================================
% restore the Mono++ overlay LUT to a linear ramp
linear_lut = repmat(round(linspace(0, 2^16 -1, 256))', 1, 3);
BitsPlusSetClut(window,linear_lut);
% draw a gray background on front and back buffers to clear out any old LUTs
Screen('FillRect',window, gray);
Screen('Flip', window);
Screen('FillRect',window, gray);
Screen('Flip', window);
% Close the window.
Screen('CloseAll');
else
% Blank the screen (zero the Mono++ overlay LUT),
% - doesn't actually quite blank the screen.
BitsPlusSetClut(window,zeros(256,3));
% draw a black background on front and back buffers to clear out any old LUTs
Screen('FillRect',window, black);
Screen('Flip', window);
Screen('FillRect',window, black);
Screen('Flip', window);
Screen('CloseAll');
end
|
