01-intro.Rmd

---
output: html_document
editor_options: 
  chunk_output_type: console
---
# rgl and bookdown eek


One chunk, two widgets. 

```{r rgl-line, echo=TRUE, eval=TRUE}
colpal <- function(n = 26, drop = 5) sf::sf.colors(n)[-seq_len(drop)]

library(rgl)
clear3d()
#p3 <- mfrow3d(1, 2, sharedMouse = TRUE)
(geometry <- cbind(x = c(0, 0.5, 1), y = c(0, 0.5, 1), z = c(0, 0, 0.8)))
(topology1 <- rbind(.v0 = c(1, 2), .v1 = c(2, 3)))
lines3d(geometry[t(topology1), ], lwd = 3, col = "firebrick")
material3d(col = "black")
axis3d("x")
axis3d("y")
axis3d("z")
title3d(xlab = "x", ylab = "y", zlab = "z")
quads3d(cbind(c(0, 1, 1, 0), c(0, 0, 1, 1), c(0, 0, 0, 0) - 0.01), col="gray")
rglwidget()
#next3d()
clear3d()
(topology2 <- rbind(.v0 = c(1, 2, 1), .v1 = c(2, 3, 1)))
triangles3d(geometry[t(topology2), ], col = "firebrick")
material3d(col = "black")
axis3d("x")
axis3d("y")
axis3d("z")
title3d(xlab = "x", ylab = "y", zlab = "z")
quads3d(cbind(c(0, 1, 1, 0), c(0, 0, 1, 1), c(0, 0, 0, 0)), col="gray")

rglwidget()
```



## Quads


Quads are a funny case, usually carried by two triangles (at least implicitly) but they are an important computer graphics element. 


## Rando

```{r rando}
rgl::clear3d()
rgl::plot3d(matrix(rnorm(27), 9, 3))
rglwidget()
```