Symbol Type
Symbol type
Three different symbol types are provided for displaying DES elements giving a trade-off between image quality and rendering speed.
Uses "points" to display particles. These are 2 dimensional squares drawn in the plane of the screen at the appropriate location, and with width and height "radius" x 2.
"Points" are drawn extremely fast in OpenGL, and since a typical analysis may have thousands of DES elements this is the default display method.
Uses a cube of width, height and depth "radius" x 2 to display particles.
This only ever shows 3 faces, so it is reasonably fast to draw, but it looks a bit odd showing a spherical element as a cube. However cubes have depth and orientation, and can be lit, so the result is better-looking that a "point".
Draws a sphere of the relevant radius, giving a "true" particle appearance. However spheres require many facets for rendering, making these slower to draw.
is a value between 1 and 5 which determines the number of facets used to render the sphere symbols. Each increment halves the equatorial and meridional angular increment size, quadrupling the number of facets on the symbol.
The default value of 1 gives a rather "pointy" looking particle symbol, but it is usually acceptable given their small size. Higher quality values may be necessary when generating images for presentation.
