ggeasy: Easy Access to 'ggplot2' Commands

tg_bounds <- function(tg,lab,theta){
  bounds <- grid:::grid.Call(grid:::L_textBounds, 
                             grDevices::as.graphicsAnnot(tg$label[lab]),
                             tg$x[lab],
                             tg$y[lab], 
                             resolveHJust(tg$just, tg$hjust), 
                             resolveVJust(tg$just,tg$vjust), 
                             tg$rot, theta)
  bounds <- unit(bounds, "inches")
  convertUnit(bounds,unitTo = attr(tg$x,'unit'),valueOnly = TRUE)
}

rg_bounds <- function(rg,lab,theta){
  bounds <- grid:::grid.Call(grid:::L_rectBounds,
                             rg$x[lab],
                             rg$y[lab],
                             rg$width[lab],
                             rg$height[lab],
                             resolveHJust(rg$just, rg$hjust), 
                             resolveVJust(rg$just,rg$vjust),
                             theta)
  bounds <- unit(bounds, "inches")
  convertUnit(bounds,unitTo = attr(rg$x,'unit'),valueOnly = TRUE)
}

extend_bound <- function(bounds,rot,draw = FALSE){
  
  #left right center points
  xy <- rotatePoint(pivot = c(mean(bounds[c(180,360),1]),bounds[180,2]),
                    point = matrix(c(median(bounds[,1])-bounds[1,3],bounds[180,2],
                                     median(bounds[,1])+bounds[1,3],bounds[180,2]),
                                   ncol=2,byrow = TRUE),
                    rot = rot)
  
  #top/bottom left vertices
  xy_l <- rotatePoint(pivot = xy[1,],
                      point = matrix(c(xy[1,1],xy[1,2]+bounds1[1,4],
                                       xy[1,1],xy[1,2]-bounds1[1,4]),
                                     ncol=2,byrow = TRUE),
                      rot = rot)
  #top/bottom right vertices
  xy_r <- rotatePoint(pivot = xy[2,],
                      point = matrix(c(xy[2,1],xy[2,2]+bounds1[2,4],
                                       xy[2,1],xy[2,2]-bounds1[2,4]),
                                     ncol=2,byrow = TRUE),
                      rot = rot)
  
  ret <- rbind(xy_l,xy_r)
  
  if(draw)
    lines(ret[c(3,1,2,4,3),1],ret[c(3,1,2,4,3),2])
  
  ret <- ret[c(3,1,2,4),]
  
  return(ret)
}

rotatePoint <- function(pivot, point, rot) {
  # Rotate clockwise, angle in radians
  rad <- rot * pi / 180
  x <- (cos(rad) * (point[,1] - pivot[1])) - (sin(rad) * (point[,2] - pivot[2])) +pivot[1]
  y <- (sin(rad) * (point[,1] - pivot[1])) + (cos(rad) * (point[,2] - pivot[2])) + pivot[2]
  return(cbind(x, y))
}

linesIntersect <- function(x1, x2, x3, x4, y1, y2, y3, y4){
  result = 0
  denom = (y4 - y3)*(x2 - x1) - (x4 - x3)*(y2 - y1)
  ua = ((x4 - x3)*(y1 - y3) - (y4 - y3)*(x1 - x3))
  
  # If the lines are parallel ...
  
    if (denom == 0) {
      # If the lines are coincident ...
      
        if (ua == 0) { 
          # If the lines are vertical ...
          
            if (x1 == x2) {
              # Compare y-values
              
                if (!((y1 < y3 && max(y1, y2) < min(y3, y4)) ||
                      (y3 < y1 && max(y3, y4) < min(y1, y2))))
                  result = 1
            } else {
              # Compare x-values
              
                if (!((x1 < x3 && max(x1, x2) < min(x3, x4)) ||
                      (x3 < x1 && max(x3, x4) < min(x1, x2))))
                  result = 1
            }
        }
    }
    else { # ... otherwise, calculate where the lines intersect ...
      
      ub = ((x2 - x1)*(y1 - y3) - (y2 - y1)*(x1 - x3))
      
      ua = ua/denom
      
      ub = ub/denom 
       # Check for overlap 
      
        if ((ua > 0 && ua < 1) && (ub > 0 && ub < 1)) 
          result = 1
    }
  return(result)
}

edgesIntersect <- function(x1, x2, y1, y2, r){ #r is LRect
  result = 0
  
  if (linesIntersect(x1, x2, r[1], r[2], y1, y2, r[5], r[6]) ||
      linesIntersect(x1, x2, r[2], r[3], y1, y2, r[6], r[7]) ||
      linesIntersect(x1, x2, r[3], r[4], y1, y2, r[7], r[8]) ||
      linesIntersect(x1, x2, r[4], r[1], y1, y2, r[8], r[1]))
    result = 1
  
  return(result)
}

rectIntersect <- function(r1,r2) {
  result = 0
  
  if (edgesIntersect(r1[1], r1[2], r1[5], r1[6], r2) ||
      edgesIntersect(r1[2], r1[2], r1[6], r1[7], r2) ||
      edgesIntersect(r1[3], r1[4], r1[7], r1[8], r2) ||
      edgesIntersect(r1[4], r1[1], r1[8], r1[1], r2))
    result = 1
  
  return(result)
}

find_rot <- function(rot,tg){
  this_tg <- tg0
  this_tg$rot <- rot
  bounds1 <- do.call('rbind',lapply(seq(1,360,1),tg_bounds,tg = this_tg,lab = 1))
  bounds2 <- do.call('rbind',lapply(seq(1,360,1),tg_bounds,tg = this_tg,lab = 2))
  plot(bounds1[,c(1:2)],type='l',xlim=c(-10,15),ylim=c(300,380))
  xy <- extend_bound(bounds1,rot = rot,draw = TRUE)
  lines(bounds2[,c(1:2)])
  xy2 <- extend_bound(bounds2,rot = rot,draw = TRUE)
  rectIntersect(r1 = c(xy),r2 = c(xy2))
}

txt <- c("Hi there","Hi there")
tg <- textGrob(label = txt,x = c(0.25,0.4),y=c(0.5,0.5))

for(rot in 0:90){
  if(find_rot(rot,tg)==0) break
}

dev.off()
grid.newpage()
fg <- frameGrob()
tg <- textGrob(label = txt,x = c(0.25,0.4),y=c(0.5,0.5))
fg <- packGrob(fg, tg0)
grid.draw(fg)

grid.newpage()
fg <- frameGrob()
rg <- rectGrob(x = tg$x, y = tg$y, width = stringWidth(tg$label), height = stringHeight(tg$label))
fg <- packGrob(fg, rg)
fg <- packGrob(fg, tg)
grid.draw(fg)