Re: [wxperl-users] WxPerl & OpenGL Question

[Mark D. <mar...@zn...>]

Hi,

My knowledge of OpenGL is very limited so the help I can offer is very
sketchy.

I think the solution to zooming is using glPushMatrix() and glTranslatef().

So in the wxGLCanvas.pm demo module, if you look at

Wx::DemoModules::wxGLCanvas::Cube->Render()

you'll see the statement

glTranslatef( 0, 0, -5 );

If you change this to glTranslatef( 0, 0, -20 );

you get a different zoom factor.

So I guess you would need to change it to something like
glTranslatef( 0, 0, $self->GetZoomFactor() );

add a couple of subs to the module:

sub GetZoomFactor {
    my $self = shift;
    return $self->{zoomfactor} || -5;
}

sub SetZoomFactor {
    my $self = shift;
    $self->{zoomfactor} = shift;
}

then add some interface element to call SetZoomFactor in response to
user request.

I think the first two params to glTranslatef() hold the answer to
panning left / right - but I'm not sure.

That's the limit of my OpenGL knowledge I'm afraid.


Regards

Mark




Vaughn Staples wrote:
> Mark,
> 
> Your examples have been immensely helpful ... thank you very much.
> 
> Could I also ask for guidance on the methods necessary to zoom in/out? 
> I have had no difficulty modifying the code to spin the cube in the 
> X/Y/Z axis, but changing the zoom perspective is beyond my grasp.  I'm 
> also seeking counsel on panning left-to-right, but I believe once I 
> solve the zoom issue that panning should not be difficult to solve on my 
> end.
> 
> Best regards,
> 
> Vaughn
> 
> ----- Original Message ----- 
> From: "Mark Dootson" <mar...@zn...>
> To: "Vaughn Staples" <vau...@in...>
> Cc: <wxp...@li...>
> Sent: Monday, March 19, 2007 5:05 PM
> Subject: Re: [wxperl-users] WxPerl & OpenGL Question
> 
> 
> Hi,
> 
> You need to install the wxDemo modules
> 
> cpan Wx::Demo.
> 
> This may give you all the info you needed.
> 
> If not, I have a couple of rough examples for you.
> 
> http://www.wxperl.co.uk/example1.txt
> 
> does exactly what you described - diplays two controls side by side.
> 
> I though that you probably wanted to have a split window so you could
> resize your filelist vs the GLCanvas so I did
> 
> http://www.wxperl.co.uk/example2.txt
> 
> to include Wx::SplitterWindow.
> 
> Both these examples use the wxGLCanvas.pm from the Wx::Demo so that
> needs to be installed.
> 
> Best Regards
> 
> Mark
> 
> 
> Vaughn Staples wrote:
>> I am trying to construct a wxPerl frame containing a menubar at the 
>> top
>> followed by twin widgets below that are tiled side-by-side.  The one 
>> to
>> the left is a listCtrl containing a list of image files, and most
>> importantly the one to the right is a glCanvas that will be used to 
>> draw
>> primitives and/or display images.
>>
>> I have studied the glCanvas "minimal.pl" distributed by Mattia but
>> cannot seem to retrofit it to solve the above purpose.
>>
>> Can anyone share guidance and/or provide a simple wxPerl example of 
>> how
>> to embed an openGL-related canvas in a wxPerl frame which contains 
>> other
>> items?
>>
>> Many thanks in advance,
>>
>> Vaughn 
>