greduce reduces the polygon count of an object while trying to keep the general shape of the object. greduce can also be run in batch mode, where no graphical interface appears and the conversion is performed from the command line only.
The Open Triangulated and Open 4 sided File menu options allows you to open the geometry with triangles or quadrilaterals as the polygon type respectively.
It is recommended that you use the percent reduction buttons for speedier operations with this tool. Files with many polygons may take a long time to reduce using the reduction factor and angle parameters.
This will start the tools interactive mode, where you can reduce the object’s polygon count using the sliders and controls provided.
There are two controls for determining the polygon reduction. These are represented as sliders at the bottom of the window. The reduction factor is the primary control. However, this should be used in conjunction with a small increase in the angle factor (e.g. 5).
To simply remove planar polygons, set the reduction factor to a small number and the angle factor to a small number (i.e. 0.001, 0.001). Beneath the sliders are a set of buttons which can be used to reduce the polygon count by differing degrees. For example, remove 10% of the polygons. These controls are approximate and are usually good to plus or minus 5%. In some cases, it will not be possible for the program to remove a large number of polygons. In these cases, hitting 90% reduction will result in a smaller percentage actually removed.
greduce [-v] [-t|-q] -r reduction_factor -a angle infile outfile
This reduces the geometry using the reduction factor and angle factor specified.
greduce [-v] [-t|-q] -p percentage [-a angle] infile outfile
This reduces the polygon count by the percentage specified. The angle does not have to be specified, though it can make a small difference in the resulting geometry.
greduce -v -p 40 -a 10 teapot.bgeo reduced.bgeo
This example will run the polygon reduction program in “batch” mode. With the -v specified, the resulting statistics will be displayed. Sample output from the above command might look like:
Used reduce = 0.151 and angle = 10 Reduced to 170 polygons. 40.9722% reduction
greduce -v -r 0.08 -a 10 teapot.bgeo reduced.bgeo
The above command will reduce the polygons in the teapot file using the parameters specified. Again, the verbose option (-v) will cause some statistics to be displayed when the program is finished. This output will look something like:
Reduced to 193 polygons. 32.9861 % reduction
Verbose option for batch mode versions
Triangulate or make quadrilaterals out of the input file
Reduction factor (corresponds to upper slider in interactive version)
Angle of reduction (corresponds to lower slider in interactive version)
The amount, expressed as a percentage, of the original geometry to reduce.