TextBackgroundColor

1
Hi,

I'd like to highlight text using the psychtoolbox3 on winxp. Using the
screen drawtext command, I see that there's a backgroundColor option,
but nothing happens when I change it (changing the color of the text
works fine).

I google around and I found this in the OSX Psychtoolbox: History of
changes:

Created a new screen command 'TextBackgroundColor' which sets the
background color of text. 'DrawText' draws not only the characters
into a window, but a full rectangle of pixels bounding the characters.
The background is the region of that rectangle not filled by
characters. By default, the text background is tranparent and the
background color setting is ignored. When the TextAlphaBlending
preference flag is set, 'DrawText' obeys the background color and
blends it into the window obeying blending rules set by Screen's new
'BlendFunction' command.

So, I set the TextAlphaBlending screen preference to 1 but to no avail.

So, does anyone know how to change the text background color or
highlight text with or without enabling alpha blending?

Tobias Andersen
2
Sorry, unsupported on Windows and Linux, MacOS/X only.

This page on our Wiki...

<http://psychtoolbox.org/wikka.php?wakka=PlatformDifferences>

...lists the most important differences between different OSs.

-mario

--- In psychtoolbox@yahoogroups.com, "curiuz" <curiuz@...> wrote:
>
> Hi,
>
> I'd like to highlight text using the psychtoolbox3 on winxp. Using the
> screen drawtext command, I see that there's a backgroundColor option,
> but nothing happens when I change it (changing the color of the text
> works fine).
>
> I google around and I found this in the OSX Psychtoolbox: History of
> changes:
>
> Created a new screen command 'TextBackgroundColor' which sets the
> background color of text. 'DrawText' draws not only the characters
> into a window, but a full rectangle of pixels bounding the characters.
> The background is the region of that rectangle not filled by
> characters. By default, the text background is tranparent and the
> background color setting is ignored. When the TextAlphaBlending
> preference flag is set, 'DrawText' obeys the background color and
> blends it into the window obeying blending rules set by Screen's new
> 'BlendFunction' command.
>
> So, I set the TextAlphaBlending screen preference to 1 but to no avail.
>
> So, does anyone know how to change the text background color or
> highlight text with or without enabling alpha blending?
>
> Tobias Andersen
>