Hardware-Assisted Visibility Sorting

Usage

Example Linux:

./havs -if data/spx.off -cf data/spx.col -of data/spx.op

Example Windows:

Release\whavs.exe -if ..\data\spx.off -cf ..\data\spx.col -of ..\data\spx.op

Rendering with pipeline optimization enabled and no LOD (for direct comparison with other volume renderers):

./havs -if data/spx.off -cf data/spx.col -of data/spx.op -none -p

Command Line Options:

./havs -options

Option	Description
-if <mesh>	OFF mesh to load (required)
-cf <colormap>	Colormap file to load
-of <opacitymap>	Opacitymap to load
-bg <float> <float> <float>	RGB background color
-sx <float>	Screen width
-sy <float>	Screen height
-el <float>	Camera elevation
-az <float>	Camera azimuth
-k <int>	K-Buffer size
-p	Pipelining optimization on
-nvbo	Disable VBO rendering
-none	No level-of-detail
-field	Field level-of-detail
-area	Area level-of-detail

The colormap defaults to a rainbow that varies hue from red to magenta
The opacitymap defaults to 0.2 everywhere
The k-buffer size defaults to 2
The level-of-detail defaults to 'field' and is only enabled for meshes with more than 1 million tetrahedra

Runtime Keys:

Key Description

ESC Exits the program

's' Saves the current frame to "image.ppm"

'l' Toggle the current level-of-detail method

Key	Description
ESC	Exits the program
's'	Saves the current frame to "image.ppm"
'l'	Toggle the current level-of-detail method

File Formats:

OFF - The OFF file format that is used in this project is a simple ASCII tetrahedral format with one scalar per vertex and a list of cells indexed from 0.

NUM_VERTICES NUM_CELLS vertex1_x vertex1_y vertex1_z vertex1_s vertex2_x vertex2_y vertex2_z vertex2_s ... vertexn_x vertexn_y vertexn_z vertexn_s cell1_id1 cell1_id2 cell1_id3 cell1_id4 cell2_id1 cell2_id2 cell2_id3 cell2_id4 ... cellm_id1 cellm_id2 cellm_id3 cellm_id4

COL - The COL format is a simple ASCII file used to specify the color portion of the transfer function as RGB values [0,1].

COLORMAP scalar_0 r_0 g_0 b_0 ... scalar_n r_n g_n b_n

OP - The OP format is a simple ASCII file used to specify the opacity portion of the transfer function as alpha values [0,1].

DENSITYMAP scalar_0 a_0 ... scalar_n a_n

Example files are provided in the data directory for testing purposes. The SuperPheonix (spx) dataset was created by Bruno Notrosso (Electricite de France).