New world record for panoramic image

This one is 70 gigapixels (590508 x 120750).
Very impressive.
They are using Silverligh to display on the Web.
Such a large image should be viewable by VLIV, it just need the file (actual format is unknown, looks to be PPM) to be converted to TIFF (actually a 64 bit TIFF).
Final image size is about 200 Gigabytes, not something you download or store easily !

Download VLIV latest version 2.5.2

Here is the direct DropBox link, and some sample images :

• a very large one (850 megabytes)
• a small one (8 megabytes)

These are tiff images that have pyramidal organization. You can also load normal Jpegs (preferably large ones), so that you can see virtual tiling in action.

Here is a medium one (15 megabytes)

OpenGL Vertex Buffer Objects

I recently updated my 3d object rendering code to VBO, introduced in OpenGL 1.5. Using them is very simple, and only need 4 additional API calls. Basically, the vertex data, normals and indexes are sent to the graphics card, stored in there, and accessed through an ID. At draw time, only one or two call with IDs are sufficient and performance is very much improved over using previous Vertex Arrays API, because no data is transfered. My frame rate was multiplied by 2 at least and I can now display up to 150 000 000 tris/s on my GeForce 8800 GTS, hardly the fastest card these days.

I also found GLEW library during this work, very nice and useful to develop OpenGL applications, because of poor header support in MS SDK. It allows using API calls without bothering if they are in headers or not, thanks to clever dynamic loading features at runtime and extensive coverage of OpenGL extensions.

Update: After some tests, the number of tris/s is about 230 000 000 on my 8800 GTS.

Chmutov surface 3d printed

I received today a new object I have computed, it is a Chmutov 8 order surface (see this for a description). I used Shapeways service and the object is 5cm square. The material is called "white glaze" and was actually quite cheap thanks to a promotion. The result is very nice, with a glossy finish and handling the object is a pleasure.

Here is a picture.

Parallelizing code

I have modified my fractal generation code to use Intel TBB. While before, on an 8 core machine I was only able to get 13% CPU usage, I now have almost 100%.

The first part I did was layer generation. This means a single parallel_for.

I have then parallelized the triangle generation part (the so-called marching cubes). To do so I have a simple parallel_for and each thread writes its computed triangles to a shared concurrent_vector. Very simple and impressively effective.

So this scales quite well and I was able to achieve an overall speedup of 6x on a 8 core machine, over a single core.