[Clam-devel] KeySpace speed up

[bennett kolasinski]

David-- very neat re: the KeySpace speedup, maybe it'll give my aging
powerbook g4 a little break :)  I'll start dusting off my OpenGL texts
now...

Attached is an initial* patch for adding BarGraph view to Annotator--
I haven't had much chance to test it in part because my computer's
running strangely today and I haven't had much luck running Annotator
with anything but the Chords example on my Mac (will investigate and
give a more detailed report when I have one...).  It compiles and
links fine though.  If anyone has a chance to run it please let me
know how it runs (I'll be lurking on IRC for a while today as well).

B

*and by 'initial' I mean 'final until somebody finds a problem with it' :)

On 6/7/07, David García Garzón <dgarcia at iua.upf.edu> wrote:
> With the help of Gonzalez bross (Sergio and Eduard) i speeded up a lot the
> render of the KeySpace view. KeySpace is no more the visualization bottle
> neck.
>
> My poor previous implementation rendered a lot of small polygons (of several
> pixels) and assigned colors to each one, Each polygon was sent vertex to
> vertex. This had a lot of Graphic system overhead.
>
> Now i just build a texture with the color of selected points (matching the
> previous polygons) and we just render a big rectangular square with such
> texture applied. Even the original pixelated look can be obtained now by free
> by not interpolating the texture.
>
> The result is impressive, even without HW acceleration now i can display
> several KeySpaces of several sizes with a minor impact on the frame rate and
> the audio playback.
>
> The mandatory screenshot:
> http://iua-share.upf.edu/wikis/clam/index.php/Development_screenshots
>
> Bennett, some ideas to you:
>
> This same idea can be used in the future to speed up the current vmqt4
> SpecgramRenderer as it also builds the image by using a lot of small colored
> polygons that can be turned into a texture.
>
> An scrolling Spectrogram for the NetworkEditor is also very easy. It just has
> to write a single column of the texture with the incoming frame data and then
> apply the texture with an offset. When texture coords go beyond 1.0 Graphic
> hw takes the texels from the begining at 0.0 so we can write it as a circular
> buffer with no fuss to the OpenGL system.
>
> Are you familiar with OpenGL? If not, we could get a talk on the irc. Once you
> have a reference implementation such as KeySpace, it is not as complicated.
>
> David.
>
>
> _______________________________________________
> Clam-devel mailing list
> Clam-devel at llistes.projectes.lafarga.org
> https://llistes.projectes.lafarga.org/cgi-bin/mailman/listinfo/clam-devel
>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: AddBarGraphViewToAnnotator_initial.patch
Type: application/octet-stream
Size: 9787 bytes
Desc: not available
URL: <http://lists.clam-project.org/pipermail/clam-devel-clam-project.org/attachments/20070607/b03eb683/attachment-0003.obj>