RE: slow 2d image generation

jim

i just switched to a DisplayImplJ3D with a TwoDDisplayRendererJ3D...the image 
did not load much faster, but it definitely looked much better (less grainy) 
and the pan/zoom functions were very smooth...basically it solved #2 and #3 
problems from my initial email, but #1 still remains....any ideas on loading 
data into visad more quickly?....the file is only 147k, so it should be quick, 
right?

thanks to jim k for the suggestion!

jc

> -----Original Message-----
> From: Jim Koutsovasilis [mailto:jimk@xxxxxxxxxx]
> Sent: Monday, January 05, 2004 4:46 PM
> To: Jim Cookas
> Cc: visad@xxxxxxxxxxxxxxxx
> Subject: Re: slow 2d image generation
> 
> 
> Hello Jim,
> 
> if you are using a DisplayImplJ2D display, try a 
> DisplayImplJ3D instead.
> It might be faster.
> 
> Regards,
> Jim.
> ---
> Jim Koutsovasilis
> Bureau of Meteorology, Australia
> jimk@xxxxxxxxxx
> 
> On Mon, Jan 05, 2004 at 04:24:52PM -0600, Jim Cookas wrote:
> > hello group
> > 
> > first off, many thanks to all who helped with my previous 
> question regarding constant maps...however, i now have a new 
> problem...
> > 
> > the application i am currently developing with visad has a 
> feature to load and display 2d image data from an ascii 
> file...i am using the textadapter class to read the file and 
> turn into a flatfield...the ascii file is in the tab-spaced 
> format that the textadapter class can read....here is a snip 
> of the first five lines of an example ascii file:
> > 
> > <snip>
> > (Down_Range,Cross_Range)->(RCS)             
> > Down_Range  Cross_Range     RCS
> > -755.383    -755.383        -124.0984508
> > -731.684    -755.383        -124.0586397
> > -707.986    -755.383        -123.995843
> > -684.288    -755.383        -123.9096856
> > 
> > ...and so on
> > </snip>
> > 
> > in this case, 'down_range' maps to the x-axis, 
> 'cross_range' maps to the y-axis, and 'rcs' maps to an rgb 
> value...everything loads and displays fine, but there are 
> three major problems:
> > 
> > 1) loading the data is ___sloooow___...the example file i 
> snipped above comes to 147515 bytes (256 x 256 image size) 
> and it takes a solid 30 seconds from when the file is opened 
> to when the image is finally displayed...we have c++ code in 
> other applications that loads and displays the same data 
> almost instantly...is it a java problem?...is it visad?...is 
> it something i'm doing wrong?
> > 
> > 2) panning and zooming of the image (and line plots for 
> that matter) are slow and choppy...when data is rendered as 
> points, these functions are very quick, smooth, and 
> acceptable...is there any way to speed up panning/zooming?
> > 
> > 3) is there any way to increase the resolution of the image 
> rendering to make it more 'smooth'?...right now it looks 
> textured...when zoomed in closely, the data points look very 
> triangular...any ideas?
> > 
> > thanks in advance for any help that can be provided...let 
> me know if you need more information from me...peace!
> > 
> > jc
> > 
> 
>