# Rpolyhedra

# Introduction

This package is a curation made based on the poly package found on https://netlib.org/polyhedra/ (Original Help message), and the polyhedra database found on http://dmccooey.com/polyhedra/, both of which provide polyhedra databases on its own format. As such, Rpolyhedra provides with the following:

1. A module to scrape the polyhedra for the different sources found with features for incremental correction of issues found and to be found in scraping process.
2. A database of the scraped polyhedra.
3. An R6 polyhedron representation with ‘rgl’ package visualizing capabilities.

# Usage

For final users, the package provides a common interface for accessing public polyhedra databases, analyze properties, compare and visualize them with RGL.

For advanced users, the package provides a simplified set of R6 objects to scrape and compare polyhedra databases.

## Get available polyhedra

Once the original files had been processed, a simple call to `getAvailablePolyhedra()` retrieves a list of the available polyhedra with properties and status in the polyhedra database:

    #show only the first 10 polyhedra.
    head(getAvailablePolyhedra(), n = 10)

    ##    source                      scraped.name            symbol vertices faces
    ## 1  netlib                       tetrahedron {3,3}\t@Y sub 3 @        4     4
    ## 31 netlib               square pyramid (j1)      \t@Y sub 4 @        5     5
    ## 42 netlib        triangular dipyramid (j12)      \t@Y sub 3 @        5     6
    ## 9  netlib                  triangular prism      \t@P sub 3 @        6     5
    ## 32 netlib           pentagonal pyramid (j2)      \t@Y sub 5 @        6     6
    ## 3  netlib                        octahedron {3,4}\t@S sub 3 @        6     8
    ## 37 netlib elongated triangular pyramid (j7)      \t@Y sub 3 @        7     7
    ## 74 netlib  augmented triangular prism (j49)      \t@Y sub 4 @        7     8
    ## 43 netlib        pentagonal dipyramid (j13)      \t@Y sub 5 @        7    10
    ## 2  netlib                              cube {4,3}\t@P sub 4 @        8     6
    ##     status
    ## 1  scraped
    ## 31 scraped
    ## 42 scraped
    ## 9  scraped
    ## 32 scraped
    ## 3  scraped
    ## 37 scraped
    ## 74 scraped
    ## 43 scraped
    ## 2  scraped

## Retrieve a polyhedron

The access to a particular polyhedron can be done with a call to `getPolyhedron(<<source>>, <<polyhedron.name>>)`, which returns a Polyhedron object. For example, to retrieve a cube from the netlib database, the call would be:

    cube <- getPolyhedron(source = "netlib", polyhedron.name = "cube")

# A demo

To try package functionality, a simple demo can be executed which shows the 5 regular polyhedra.

    # 1.  Obtain 5 regular solids
    polyhedra.2.draw <- getAvailablePolyhedra(source = "netlib")
    polyhedra.2.draw <- polyhedra.2.draw %>%
                            filter(scraped.name %in%
                                c("tetrahedron", "octahedron", "cube",
                                   "icosahedron", "dodecahedron"))

    # 2. Setup colors and scales
    n <- nrow(polyhedra.2.draw)
    polyhedron.colors <- rainbow(n)
    polyhedron.scale <- 5

    # 3. Open and setup RGL window
    open3d()

    ## glX
    ##   1

    par3d(FOV = 1)
    rgl.bg( sphere =FALSE, fogtype = "none", color=c("black"))
    rgl.viewpoint(theta = 0, phi=0, zoom=0.8, fov=1)

    # 4. For each polyhedron, setup rotation, position and render
    for (i in seq_len(n)) {
      # Obtain polyhedron
      polyhedron.row <- polyhedra.2.draw[i,]
      polyhedron.name <- polyhedron.row$scraped.name
      polyhedron <- getPolyhedron(source = polyhedron.row$source, polyhedron.name)

      # Setup angles, position into transformationMatrix
      current.angle <- i/n * 2 * pi
      tm <- rotationMatrix(current.angle, 1, 0, 0)
      x.pos <- round(polyhedron.scale * sin(current.angle), 2)
      y.pos <- round(polyhedron.scale * cos(current.angle), 2)
      tm <- tm %*% translationMatrix(x.pos, y.pos, 0)

      # Render
      print(paste("Drawing ", polyhedron.name, " rotated ", round(current.angle, 2),
                  " in (1,0,0) axis. Translated to (", x.pos, ",", y.pos, ",0)",
                  " with color ", polyhedron.colors[i], sep = ""))
      shape.rgl <- polyhedron$getRGLModel(transformation.matrix = tm)
      shade3d(shape.rgl, color = polyhedron.colors[i])
    }

    ## [1] "Drawing tetrahedron rotated 1.26 in (1,0,0) axis. Translated to (4.76,1.55,0) with color #FF0000"
    ## [1] "Drawing octahedron rotated 2.51 in (1,0,0) axis. Translated to (2.94,-4.05,0) with color #CCFF00"
    ## [1] "Drawing cube rotated 3.77 in (1,0,0) axis. Translated to (-2.94,-4.05,0) with color #00FF66"
    ## [1] "Drawing icosahedron rotated 5.03 in (1,0,0) axis. Translated to (-4.76,1.55,0) with color #0066FF"
    ## [1] "Drawing dodecahedron rotated 6.28 in (1,0,0) axis. Translated to (0,5,0) with color #CC00FF"