/usr/share/psychtoolbox-3/PsychDemos/DotDemo.m is in psychtoolbox-3-common 3.0.9+svn2579.dfsg1-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 | function DotDemo(showSprites, waitframes)
%
% dot motion demo using SCREEN('DrawDots') subfunction
%
% Usage: DotDemo([showSprites = 0][, waitframes = 1]);
%
% The optional parameter 'showSprites' when set to 1, will draw little
% smiley textures instead of dots, demonstrating sprite-drawing. A zero
% setting, or omitting the setting, will draw dots. A value of 2 will draw
% filled rectangles via textures instead, (ab-)using texture drawing and
% filtering to allow subpixel positioning of drawn rectangles on the
% screen. We slow down the animation for non-zero 'showSprites' so you can
% appreciate the anti-aliased smooth subpixel movement better.
%
% 'waitframes' Number of video refresh intervals to show each image before
% updating the dot field. Defaults to 1 if omitted.
%
% You can exit the demo by any keypress or mouse button press. It will also
% exit by itself after 1000 redraws.
%
% The top of the demo code contains tons of parameters to tweak and
% manipulate if you want.
%
%
% Note: Some versions of MacOS/X have defective dot drawing due to an
% operating system bug. If you happen to have such a system (e.g., OS/X
% 10.6.3 with NVidia Geforce-7xxx hardware) then read "help ScreenDrawDots"
% for a workaround.
%
% Original author: Keith Schneider, 12/13/04
%HISTORY
%
% mm/dd/yy
%
% 12/13/04 kas Wrote it.
% 1/11/05 awi Merged into Psychtoolbox.org distribution.
% -Changed name from "dot_demo" to "DotDemo" to match
% Psychtooblox conventions.
% -Changed calls to "Screen" from "SCREEN" to avoid
% case warning.
% -Added HISTORY section to comments.
% 1/13/05 awi Merged in Mario Kleiner's modifications to agree with
% his changes to Screen 'DrawDots' and also time performance:
% -Increases number of dots (ndots) by 10x
% -Decreases width dot (dot_w) from 0.3 to 0.1
% -Changed the 'OpenWindow' call to specify double
% buffers for onscreen window and 32-bit depth
% -Transpose second argument to Screen 'DrawDots'.
% Mario interchanged x&y matrix axes in this 'DrawDots'
% argument because it allows a direct copy from a MATLAB matrix
% into an OpenGL structure, without memory reordering, which
% is slow. This is controversial because the Psychtoolbox
% uniformly interprets matrix M axis (rows) as screen Y axis and
% matrix N (columns) as screen N axis. This change breaks that
% convention.
% -Add calls to GetSeccs to time performance.
% 3/22/05 mk Added code to show how to specify different color and
% size for each single dot.
% 4/23/05 mk Add call to Screen('BlendFunction') to reenable
% point-smoothing.
% 4/23/05 fwc changed color and size specifications to use 'rand',
% rather than 'random'
% differentsizes is now max size value for random size
% assigment. Decrease nr of dots when differentsizes>0
% added option to break out of loop by pressing key or
% mouse button.
% Will now default to max of screens rather than main
% screen.
% 5/31/05 mk Some modifications to use new Flip command...
% 4/18/10 mk Add support for demo'ing PsychDrawSprites2D() command.
AssertOpenGL;
if nargin < 1
showSprites = [];
end
if isempty(showSprites)
showSprites = 0;
end
if nargin < 2
waitframes = [];
end
if isempty(waitframes)
waitframes = 1;
end
try
% ------------------------
% set dot field parameters
% ------------------------
nframes = 3600; % number of animation frames in loop
mon_width = 39; % horizontal dimension of viewable screen (cm)
v_dist = 60; % viewing distance (cm)
if showSprites > 0
dot_speed = 0.07; % dot speed (deg/sec) - Take it sloooow.
f_kill = 0.00; % Don't kill (m)any dots, so user can see better.
else
dot_speed = 7; % dot speed (deg/sec)
f_kill = 0.05; % fraction of dots to kill each frame (limited lifetime)
end
ndots = 2000; % number of dots
max_d = 15; % maximum radius of annulus (degrees)
min_d = 1; % minumum
dot_w = 0.1; % width of dot (deg)
fix_r = 0.15; % radius of fixation point (deg)
differentcolors =1; % Use a different color for each point if == 1. Use common color white if == 0.
differentsizes = 2; % Use different sizes for each point if >= 1. Use one common size if == 0.
% waitframes = 1; % Show new dot-images at each waitframes'th monitor refresh.
if differentsizes>0 % drawing large dots is a bit slower
ndots=round(ndots/5);
end
% ---------------
% open the screen
% ---------------
screens=Screen('Screens');
screenNumber=max(screens);
[w, rect] = Screen('OpenWindow', screenNumber, 0);
% If you'd uncomment these lines and had the Psychtoolbox kernel driver
% loaded on a OS/X or Linux box with ATI Radeon X1000 or later, you'd
% probably enjoy a 10 bit per color channel framebuffer...
%PsychImaging('PrepareConfiguration');
%PsychImaging('AddTask', 'General', 'FloatingPoint16Bit');
%PsychImaging('AddTask', 'General', 'EnableNative10BitFramebuffer');
%[w, rect] = PsychImaging('OpenWindow', screenNumber, 0,[], [], doublebuffer+1);
% Enable alpha blending with proper blend-function. We need it
% for drawing of smoothed points:
Screen('BlendFunction', w, GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
[center(1), center(2)] = RectCenter(rect);
fps=Screen('FrameRate',w); % frames per second
ifi=Screen('GetFlipInterval', w);
if fps==0
fps=1/ifi;
end;
white = WhiteIndex(w);
HideCursor; % Hide the mouse cursor
Priority(MaxPriority(w));
% Do initial flip...
vbl=Screen('Flip', w);
% ---------------------------------------
% initialize dot positions and velocities
% ---------------------------------------
ppd = pi * (rect(3)-rect(1)) / atan(mon_width/v_dist/2) / 360; % pixels per degree
pfs = dot_speed * ppd / fps; % dot speed (pixels/frame)
s = dot_w * ppd; % dot size (pixels)
fix_cord = [center-fix_r*ppd center+fix_r*ppd];
rmax = max_d * ppd; % maximum radius of annulus (pixels from center)
rmin = min_d * ppd; % minimum
r = rmax * sqrt(rand(ndots,1)); % r
r(r<rmin) = rmin;
t = 2*pi*rand(ndots,1); % theta polar coordinate
cs = [cos(t), sin(t)];
xy = [r r] .* cs; % dot positions in Cartesian coordinates (pixels from center)
mdir = 2 * floor(rand(ndots,1)+0.5) - 1; % motion direction (in or out) for each dot
dr = pfs * mdir; % change in radius per frame (pixels)
dxdy = [dr dr] .* cs; % change in x and y per frame (pixels)
% Create a vector with different colors for each single dot, if
% requested:
if (differentcolors==1)
colvect = uint8(round(rand(3,ndots)*255));
else
colvect=white;
end;
% Create a vector with different point sizes for each single dot, if
% requested:
if (differentsizes>0)
s=(1+rand(1, ndots)*(differentsizes-1))*s;
end;
% Wanna show textured sprites instead of dots?
if showSprites == 1
% Create a small texture as offscreen window: Size is 30 x 30
% pixels, background color is black and transparent:
tex = Screen('OpenOffScreenWindow', w, [0,0,0,0], [0 0 30 30]);
% Draw a little white smiley into the window. The white color will
% be modulated by 'colvect' during drawing, so white is basically
% just a placeholder:
Screen('TextSize', tex, 24);
Screen('DrawText', tex, ':)', 0, 0, 255);
% Scale down a bit, otherwise visual clutter ensues:
s = s * 0.2;
% Define randomly distributed rotation angles in a +/- 30 degree
% range around a "vertical" smiley face:
angles = (rand(1, ndots) - 0.5) * 60 + 90;
end
if showSprites == 2
% Create a small texture as offscreen window: Size is 30 x 30
% pixels, background color is black and transparent:
tex = Screen('OpenOffScreenWindow', w, [255,255,255,0], [0 0 30 30]);
% Draw a white rectangle into the window. The white color will
% be modulated by 'colvect' during drawing, so white is basically
% just a placeholder:
Screen('FillRect', tex, 255, [1 1 29 29]);
s = 1;
% Define randomly distributed rotation angles in a +/- 30 degree
% range around a "vertical" smiley face:
angles = (rand(1, ndots) - 0.5) * 60 + 90;
end
% --------------
% animation loop
% --------------
for i = 1:nframes
if (i>1)
Screen('FillOval', w, uint8(white), fix_cord); % draw fixation dot (flip erases it)
if showSprites
% Draw little "sprite textures" instead of dots:
PsychDrawSprites2D(w, tex, xymatrix, s, angles, colvect, center, 1); % change 1 to 0 to draw unfiltered sprites.
else
% Draw nice dots:
Screen('DrawDots', w, xymatrix, s, colvect, center,1); % change 1 to 0 to draw square dots
end
Screen('DrawingFinished', w); % Tell PTB that no further drawing commands will follow before Screen('Flip')
end;
% Break out of animation loop if any key on keyboard or any button
% on mouse is pressed:
[mx, my, buttons]=GetMouse(screenNumber);
if any(buttons)
break;
end
if KbCheck
break;
end;
xy = xy + dxdy; % move dots
r = r + dr; % update polar coordinates too
% check to see which dots have gone beyond the borders of the annuli
r_out = find(r > rmax | r < rmin | rand(ndots,1) < f_kill); % dots to reposition
nout = length(r_out);
if nout
% choose new coordinates
r(r_out) = rmax * sqrt(rand(nout,1));
r(r<rmin) = rmin;
t(r_out) = 2*pi*(rand(nout,1));
% now convert the polar coordinates to Cartesian
cs(r_out,:) = [cos(t(r_out)), sin(t(r_out))];
xy(r_out,:) = [r(r_out) r(r_out)] .* cs(r_out,:);
% compute the new cartesian velocities
dxdy(r_out,:) = [dr(r_out) dr(r_out)] .* cs(r_out,:);
end;
xymatrix = transpose(xy);
vbl=Screen('Flip', w, vbl + (waitframes-0.5)*ifi);
end;
Priority(0);
ShowCursor
Screen('CloseAll');
catch
Priority(0);
ShowCursor
Screen('CloseAll');
end
|