Hi all, is there any likelihood or possibility of such a function
being incorporated into the Psychtoolbox?
Many thanks, Luke
being incorporated into the Psychtoolbox?
Many thanks, Luke
I don't know if such a function is likely to come out, but I always
approximate the height of text by the width of two e's.
TextHeight = SCREEN(win, 'TextWidth', 'ee');
Not perfect, but it usually works well enough.
Charles.
approximate the height of text by the width of two e's.
TextHeight = SCREEN(win, 'TextWidth', 'ee');
Not perfect, but it usually works well enough.
Charles.
On Tuesday, January 18, 2005, at 11:07 AM, lukephi wrote:
>
>
> Hi all, is there any likelihood or possibility of such a function
> being incorporated into the Psychtoolbox?
>
> Many thanks, Luke
>
>
>
>
>
> Post your message to: psychtoolbox@yahoogroups.com
> Please indicate OS9, OSX, or WIN version, and include your full name.
> Denis Pelli, David Brainard, and Allen Ingling.
> http://psychtoolbox.org
>
> Yahoo! Groups Links
>
>
>
>
>
>
>
>
----------------------------------------------------------------------
Charles A. Collin, Ph.D.
Université d' Ottawa
École de Psychologie
125, rue Université
Pavillon Montpetit, pièce 408C
Ottawa, Ontario.
K1N 6N5
Téléphone: 613-562-5800 #4296
Courriel: ccollin@...
TextWidth is provided by QuickDraw, which does not provide anything
like a TextHeight. However, the psychtoolbox does include TextBounds,
which provides both. "help TextBounds".
Note that TextWidth is very fast, while TextBounds is quite slow.
best
denis
p.s.
i note that through some oversight, TextBounds.m has not been copied
from the OS9 Psychtoolbox to the OSX Psychtoolbox. It should be easy to
port. I've pasted it below. We'll try to get it into the next OSX
release.
like a TextHeight. However, the psychtoolbox does include TextBounds,
which provides both. "help TextBounds".
Note that TextWidth is very fast, while TextBounds is quite slow.
best
denis
p.s.
i note that through some oversight, TextBounds.m has not been copied
from the OS9 Psychtoolbox to the OSX Psychtoolbox. It should be easy to
port. I've pasted it below. We'll try to get it into the next OSX
release.
On Jan 18, 2005, at 11:07 AM, lukephi wrote:
>
>
> Hi all, is there any likelihood or possibility of such a function
> being incorporated into the Psychtoolbox?
>
> Many thanks, Luke
>
>
function bounds=TextBounds(w,text)
% bounds=TextBounds(window,string)
%
% Returns the smallest enclosing rect for the drawn text, relative to
% the current location. This bound is based on the actual pixels
% drawn, so it incorporates effects of text smoothing, etc. "text"
% may be a cell array or matrix of 1 or more strings. The strings are
% drawn one on top of another, at the same initial position, before
% the bounds are calculated. This returns the smallest box that will
% contain all the strings. The prior contents of the scratch window
% are lost. Usually it should be an offscreen window, so the user
% won't see it. The scratch window should be at least twice as wide
% as the text, because the text is drawn starting at the left-right
% center of the window to cope with uncertainties about text
% direction (e.g. Hebrew) and some unusual characters that extend
% greatly to the left of their nominal starting point. If you only
% know your nominal text size and number of characters, you might do
% this to create your scratch window:
%
% w=Screen(-1,'OpenOffscreenWindow',[],[0 0 3*textSize*length(string)
2*textSize],1);
%
% The suggested window size in that call is generously large because
there
% aren't any guarantees from the font makers about how big the text
might
% be for a specified point size. The pixelSize of 1 (the last argument)
% minimizes the memory requirements.
%
% Be warned that TextBounds and TextCenteredBounds are slow (taking many
% seconds) if the window is large. They use the whole window, so if the
% window is 1024x1204 they process a million pixels. The two slowest
calls
% are Screen 'GetImage' and FIND. Their processing time is proportional
to
% the number of pixels in the window. We haven't checked, but it's very
% likely that processing time is also proportional to pixel size, so we
% suggest using a small pixel size (e.g. 1 bit, using an offscreen
% window).
%
% The user interface would be cleaner if this function opened and closed
% its own offscreen window, without bothering the user. Unfortunately
the Mac
% OS takes on the order of a second to open and to close an offscreen
% window, making the overhead prohibitive.
%
% Also see TextCenteredBounds.
% 9/1/98 dgp wrote it.
% 3/19/00 dgp debugged it.
% 11/17/02 dgp Added fix, image1(:,:,1), suggested by Keith Schneider
to
% support 16 and 32 bit images.
% 9/16/04 dgp Suggest a pixelSize of 1.
% 12/16/04 dgp Fixed handling of cell array.
% 12/17/04 dgp Round x0 so bounds will always be integer. Add comment
about speed.
Screen(w,'FillRect',0);
r=Screen(w,'Rect');
x0=round((r(RectLeft)+r(RectRight))/2);
y0=round((r(RectTop)+2*r(RectBottom))/3);
if iscell(text)
for i=1:length(text)
string=char(text(i));
Screen(w,'DrawText',string,x0,y0,255);
end
else
for i=1:size(text,1)
string=char(text(i,:));
Screen(w,'DrawText',string,x0,y0,255);
end
end
% Screen(w,'DrawText','',x0,y0); % Set pen position to x0 y0.
image1=Screen(w,'GetImage');
[y,x]=find(image1(:,:,1));
if isempty(y) | isempty(x)
bounds=[0 0 0 0];
else
bounds=SetRect(min(x)-1,min(y)-1,max(x),max(y));
bounds=OffsetRect(bounds,-x0,-y0);
end