meshviewer and siro2mesh

The following are brief note for users of "meshviewer", written initially to aid in the interactive viewing of large textured meshes from the "sirovision" software but suitable for other sources of mesh data. The main aim of developing this was to support analysis features not available in the existing viewers, to present the data in various novels displays (stereoscopic and dome), and general to be in more control of a viewer rather than rely on feature support by commercial applications.

• Run the siro2mesh software, this extracts the mesh component.
  For example: siro2mesh sample5.tif
  This will create a file called "sample5.mesh".

• Open the tiff file in an image processing package, eg: Photoshop and save as a TGA file. For example in the above it may be saved as sample5.tga.

To view the mesh and associated texture

Run the software "meshviewer", for example: meshviewer sample5.mesh
To overlay the texture: meshviewer -t sample5.tga sample5.mesh

Use the left mouse button to rotate the mesh, use the centre mouse button to roll the mesh, use the right mouse key to access the popup menus. "+" and "-" to zoom ... see command usage for further options.

The mesh file format is particularly simple. The first line contains the dimensions of the mesh, that is, the number of vertices along each axis. The subsequent lines each consist of 8 floating point numbers. They are: the (x,y,z) coordinate of the vertex, the (u,v) values at that vertex, and finally the (r,g,b) value at that vertex. Note that the (r,g,b) value may optionally not be used if a texture image is supplied to "meshviewer". A sample mesh file is given here: sample5.mesh.zip.

The following screen dumps illustrate a few aspects of the viewer. They use the texture map given below and the mesh file provided above.

Information display	Reshading

Command line usage

Usage: meshviewer [options] mesh_file_name
Options
   -h                           This text
   -d                           Debug/verbose mode
   -f                           Full screen
   -s                           Active stereo
   -ss                          Dual screen stereo
   -a                           Auto rotate
   -rw                          Wireframe
   -rf                          Flat shading
   -rs                          Diffuse shaded
   -rp                          Specular shaded
   -su n                        Sub sample mesh drawing by n
   -t s                         Optional texture image
   -bg r g b                    Background colour
   -l s                         Open a list of mesh files
   -c s                         Optional specification file
   -w s                         Mesh file for warping
   -fly                         Start in fly navigation mode, otherwise inspect

Interface
   Right mouse button           Popup menus
   Center mouse button          Roll camera
   [ ]                          Roll camera
   Left mouse button            Rotate camera (depends on navigation mode)
   Arrow keys                   Rotate camera (depends on navigation mode)
   Left mouse button + shift    Pan camera
   Arrow keys + shift           Pan camera
   Center mouse button + shift  Move camera forward or backward
   < >                          Move camera forward or backward
   + -                          Zoom in/out by changing aperture (ignored in fisheye)
   a A                          Automatic rotation
   9 0                          Change zero parallax distance (stereo only)
   i h c                        Information, help, construction lines
   f1 ... f6                    Special camera views
   1 2 3 ...                    Render modes
   n                            Flip surface normals
   w                            Window dump to TGA file
   r                            Toggle continuous window dump (Use with care)
   q esc                        Quit