# Rpolyhedra.Rmd

title: "Rpolyhedra" output: rmarkdown::html_vignette vignette: > %\VignetteIndexEntry{r} %\VignetteEngine{knitr::rmarkdown}

## \usepackage[utf8]{inputenc}

# Introduction

This package is a curation made based on the poly package found on http://www.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:

- 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.
- A database of the scraped polyhedra.
- 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.

```
library(rgl)
library(dplyr)
library(Rpolyhedra)
setupKnitr()
```

## 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)
```

## 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()
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])
}
```