The strategy to draw a court is to define the different lines and use geom_path to draw each segment. For circles, we use the following function to create the x-y coordinates. For lines, we just define x-y start and end coordinates.
library(ggplot2)
draw_circle <- function(center = c(0, 0),
diameter = 1,
npoints = 12000,
start = 0,
end = 2){
tt <- seq(start*pi, end*pi, length.out = npoints)
data.frame(
x = center[1] + diameter / 2 * cos(tt),
y = center[2] + diameter / 2 * sin(tt)
)
}Now, we can define each line of the court. Our court dimensions go from -20 to 20 by -10 to 10, which would be 40x20.
side_and_goal_lines <-
data.frame(x = c(-20, 20, 20, -20, -20),
y = c(-10, -10, 10, 10, -10))
center_line <-
data.frame(x = c(0, 0),
y = c(-10, 10))
goal1 <-
data.frame(x = c(-20, -20),
y = c(-1.5, 1.5))
goal2 <-
data.frame(x = c(20, 20),
y = c(-1.5, 1.5))
front6_1 <-
data.frame(x = c(-14, -14),
y = c(-1.5, 1.5))
front6_2 <-
data.frame(x = c(14, 14),
y = c(-1.5, 1.5))
quart_circle6_1_1 <-
draw_circle(center = c(-20, -1.5),
diameter = 12,
start = 1.5, end = 2)
quart_circle6_1_2 <-
draw_circle(center = c(-20, 1.5),
diameter = 12,
start = 0, end = 0.5)
quart_circle6_2_1 <-
draw_circle(center = c(20, -1.5),
diameter = 12,
start = 1, end = 1.5)
quart_circle6_2_2 <-
draw_circle(center = c(20, 1.5),
diameter = 12,
start = 0.5, end = 1)
# Both 9m circles will be linked by a straight 3m line
free_thr9_1_1 <-
draw_circle(center = c(-20, -1.5),
diameter = 18,
start = 1.62, end = 2)
free_thr9_1_2 <-
draw_circle(center = c(-20, 1.5),
diameter = 18,
start = 0, end = 0.38)
free_thr_compl1 <- rbind(free_thr9_1_1, free_thr9_1_2)
# Both 9m circles will be linked by a straight 3m line
free_thr9_2_1 <-
draw_circle(center = c(20, -1.5),
diameter = 18,
start = 1, end = 1.38)
free_thr9_2_2 <-
draw_circle(center = c(20, 1.5),
diameter = 18,
start = 0.62, end = 1)
free_thr_compl2 <- rbind(free_thr9_2_2, free_thr9_2_1)
goal_restr_1 <-
data.frame(x = c(-16, -16),
y = c(-0.075, 0.075))
goal_restr_2 <-
data.frame(x = c(16, 16),
y = c(-0.075, 0.075))
sevenm_1 <-
data.frame(x = c(-13, -13),
y = c(-0.5, 0.5))
sevenm_2 <-
data.frame(x = c(13, 13),
y = c(-0.5, 0.5))
substitution_1 <-
data.frame(x = c(-4.5, -4.5),
y = c(-10.15, -9.85))
substitution_2 <-
data.frame(x = c(4.5, 4.5),
y = c(-10.15, -9.85))
side_and_goal_lines_half <-
data.frame(x = c(5, 20, 20, 5, 5),
y = c(-10, -10, 10, 10, -10))
six_m1 <- rbind(quart_circle6_1_1, quart_circle6_1_2)
six_m2 <- rbind(quart_circle6_2_1, quart_circle6_2_2)We are ready to pass these lines to a ggplot for a complete court. Let’s create a function so we can make small modification to the plot with some parameters and to make easy to calls to our plot creation
As parameters:
vertical: If we want to see a vertical plot
flip: Flips the plot 180°
court_color: Parameter as a hex code or ggplot color name (for example: ‘orange’ or ‘#cfa03c’) for the court
area_color: Parameter as a hex code or ggplot color name for the 6-meter area.
lines_color: Parameter as a hex code or ggplot color name for all the lines
court <- function(vertical = FALSE, flip = FALSE, court_color = '#1871c9',
area_color = '#d1b111', lines_color = 'white'){
make_flip <- NULL
if(flip) make_flip <- '-'
type_of_plot <-
ifelse(vertical,
paste0('aes(y, ', make_flip, 'x)'),
paste0('aes(', make_flip, 'x, ', 'y)'))
plot <- ggplot(mapping = eval(parse(text = type_of_plot))) +
geom_path(data = side_and_goal_lines, size = 1, color = lines_color) +
geom_path(data = goal1, color = 'red', size = 1.5) +
geom_path(data = goal2, color = 'red', size = 1.5) +
geom_polygon(data = side_and_goal_lines, fill = court_color) +
geom_path(data = center_line, size = 1, color = lines_color) +
geom_polygon(data = six_m1, fill = area_color) +
geom_polygon(data = six_m2, fill = area_color) +
geom_path(data = front6_1, size = 1, color = lines_color) +
geom_path(data = front6_2, size = 1, color = lines_color) +
geom_path(data = quart_circle6_1_1, size = 1, color = lines_color) +
geom_path(data = quart_circle6_1_2, size = 1, color = lines_color) +
geom_path(data = quart_circle6_2_1, size = 1, color = lines_color) +
geom_path(data = quart_circle6_2_2, size = 1, color = lines_color) +
geom_path(data = free_thr_compl1, linetype = 'dashed', size = 1, color = lines_color) +
geom_path(data = free_thr_compl2, linetype = 'dashed', size = 1, color = lines_color) +
geom_path(data = goal_restr_1, size = 1, color = lines_color) +
geom_path(data = goal_restr_2, size = 1, color = lines_color) +
geom_path(data = sevenm_1, size = 1, color = lines_color) +
geom_path(data = sevenm_2, size = 1, color = lines_color) +
geom_path(data = substitution_1, size = 1, color = lines_color) +
geom_path(data = substitution_2, size = 1, color = lines_color) +
coord_fixed() + # We want to maintain the 40x20 proportion
theme_void()
return(plot)
}And half a court with the same parameters.
half_court <- function(vertical = TRUE, flip = FALSE, court_color = '#1871c9',
area_color = '#d1b111', lines_color = 'white'){
make_flip <- NULL
if(flip) make_flip <- '-'
type_of_plot <-
ifelse(vertical,
paste0('aes(y, ', make_flip, 'x)'),
paste0('aes(', make_flip, 'x, ', 'y)'))
plot <- ggplot(mapping = eval(parse(text = type_of_plot))) +
geom_path(data = side_and_goal_lines_half, size = 1, color = lines_color) +
geom_polygon(data = side_and_goal_lines_half, fill = court_color) +
geom_polygon(data = six_m2, fill = area_color) +
geom_path(data = goal2, color = 'red', size = 1.5) +
geom_path(data = front6_2, size = 1, color = lines_color) +
geom_path(data = quart_circle6_2_1, size = 1, color = lines_color) +
geom_path(data = quart_circle6_2_2, size = 1, color = lines_color) +
geom_path(data = free_thr_compl2, linetype = 'dashed', size = 1, color = lines_color) +
geom_path(data = goal_restr_2, size = 1, color = lines_color) +
geom_path(data = sevenm_2, size = 1, color = lines_color) +
coord_fixed() +
theme_void()
return(plot)
}Now we draw a court:
court()
And half a court:
half_court(vertical = TRUE, flip = TRUE,
court_color = 'orange',
area_color = 'darkgreen',
lines_color = 'darkblue')
As the code to generate the court in ggplot ends with a theme_void() call at the end of our function, we can extend this plot and add other information on top.
For example, let’s generate some data on where some shots were taken and if they were a goal or not:
shots <-
data.frame(x = c(-13, -12, 11, -11, 9.5),
y = c(2, 5, -3, -1, 0),
goal = c(1, 0, 1, 1, 0))Now we just generate out court and then add our new layer.
court() +
geom_point(data = shots, aes(x, y),
color = ifelse(shots$goal == 1, 'Green', 'Red'),
size = 4)
