Move y-axis grid lines/labels into panel object

We need to control the y-axis line and label locations for each panel
in order to support a log y-axis in a panel.

See #103.

R/plot.R

@@ -1174,6 +1174,7 @@ new.replot_xts <- function(panel=1,asp=1,xlim=c(1,10),ylim=list(structure(c(1,10
  panel$is_ylim_fixed <- is_ylim_fixed
  panel$header <- header
 
+ ### actions
  panel$actions <- list()
  panel$add_action <-
  function(expr,
@@ -1193,7 +1194,8 @@ new.replot_xts <- function(panel=1,asp=1,xlim=c(1,10),ylim=list(structure(c(1,10
  Env$last_action_panel_id <<- panel$id
  }
 
- # NOTE: the header action must be the 1st action for a panel
+ ### header
+ # NOTE: this must be the 1st action for a panel
  header_expr <-
  expression({
  text(x = xlim[1],
@@ -1208,7 +1210,71 @@ new.replot_xts <- function(panel=1,asp=1,xlim=c(1,10),ylim=list(structure(c(1,10
  })
  panel$add_action(header_expr, env = panel)
 
- # y-axis
+ ### y-axis
+ panel$y_grid_lines <-
+ function(ylim)
+ {
+ p <- pretty(ylim, Env$yaxis.ticks)
+ p <- p[p >= ylim[1] & p <= ylim[2]]
+ return(p)
+ }
+
+ yaxis_expr <-
+ function(ylim_expr,
+ yaxis_left,
+ yaxis_right)
+ {
+
+ # y-axis grid lines
+ exp <- substitute({
+ segments(x0 = xlim[1], y0 = y_grid_lines(ylim_expr),
+ x1 = xlim[2], y1 = y_grid_lines(ylim_expr),
+ col = theme$grid,
+ lwd = grid.ticks.lwd,
+ lty = grid.ticks.lty)
+ }, list(ylim_expr = substitute(ylim_expr)))
+
+ # y-axis grid labels
+ if (yaxis_left) {
+ # left y-axis labels
+ exp <- c(exp,
+ substitute({
+ text(x = xlim[1],
+ y = y_grid_lines(ylim_expr),
+ labels = noquote(format(y_grid_lines(ylim_expr), justify = "right")),
+ col = theme$labels,
+ srt = theme$srt,
+ offset = 0.5,
+ pos = 2,
+ cex = theme$cex.axis,
+ xpd = TRUE)
+ }, list(ylim_expr = substitute(ylim_expr)))
+ )
+ }
+
+ if (yaxis_right) {
+ # right y-axis labels
+ exp <- c(exp,
+ substitute({
+ text(x = xlim[2],
+ y = y_grid_lines(ylim_expr),
+ labels = noquote(format(y_grid_lines(ylim_expr), justify = "right")),
+ col = theme$labels,
+ srt = theme$srt,
+ offset = 0.5,
+ pos = 4,
+ cex = theme$cex.axis,
+ xpd = TRUE)
+ }, list(ylim_expr = substitute(ylim_expr)))
+ )
+ }
+
+ ### y-axis labels
+ exp <- c(exp, expression(title(ylab = ylab[1], mgp = c(1, 1, 0))))
+
+ return(exp)
+ }
+
  if (is.null(draw_left_yaxis)) {
  draw_left_yaxis <- Env$theme$lylab
  }
@@ -1321,59 +1387,6 @@ new.replot_xts <- function(panel=1,asp=1,xlim=c(1,10),ylim=list(structure(c(1,10
  }
  }
 
- yaxis_expr <-
- function(ylim_expr,
- yaxis_left,
- yaxis_right)
- {
- # y-axis grid lines and labels
- exp <- substitute({
- segments(x0 = xlim[1], y0 = y_grid_lines(ylim_expr),
- x1 = xlim[2], y1 = y_grid_lines(ylim_expr),
- col = theme$grid,
- lwd = grid.ticks.lwd,
- lty = grid.ticks.lty)
- }, list(ylim_expr = substitute(ylim_expr)))
-
- if (yaxis_left) {
- # left y-axis labels
- exp <- c(exp,
- substitute({
- text(x = xlim[1],
- y = y_grid_lines(ylim_expr),
- labels = noquote(format(y_grid_lines(ylim_expr), justify = "right")),
- col = theme$labels,
- srt = theme$srt,
- offset = 0.5,
- pos = 2,
- cex = theme$cex.axis,
- xpd = TRUE)
- }, list(ylim_expr = substitute(ylim_expr)))
- )
- }
-
- if (yaxis_right) {
- # right y-axis labels
- exp <- c(exp,
- substitute({
- text(x = xlim[2],
- y = y_grid_lines(ylim_expr),
- labels = noquote(format(y_grid_lines(ylim_expr), justify = "right")),
- col = theme$labels,
- srt = theme$srt,
- offset = 0.5,
- pos = 4,
- cex = theme$cex.axis,
- xpd = TRUE)
- }, list(ylim_expr = substitute(ylim_expr)))
- )
- }
-
- # y labels
- exp <- c(exp, expression(title(ylab = ylab[1], mgp = c(1, 1, 0))))
-
- return(exp)
- }
 
  # return
  replot_env <- new.env()
@@ -1382,7 +1395,6 @@ new.replot_xts <- function(panel=1,asp=1,xlim=c(1,10),ylim=list(structure(c(1,10
  replot_env$add_main_header <- add_main_header
  replot_env$add_main_xaxis <- add_main_xaxis
  replot_env$new_panel <- new_panel
- replot_env$yaxis_expr <- yaxis_expr
  replot_env$get_xcoords <- get_xcoords
  replot_env$update_panels <- update_panels
  replot_env$render_panels <- render_panels
@@ -1394,13 +1406,6 @@ new.replot_xts <- function(panel=1,asp=1,xlim=c(1,10),ylim=list(structure(c(1,10
 
  replot_env$new_environment <- function() { new.env(TRUE, Env) }
 
- # function to plot the y-axis grid lines
- replot_env$Env$y_grid_lines <- function(ylim) {
- p <- pretty(ylim, Env$yaxis.ticks)
- p <- p[p >= ylim[1] & p <= ylim[2]]
- return(p)
- }
-
  # function to plot the x-axis grid lines
  replot_env$Env$x_grid_lines <- function(x, ticks.on, ylim)
  {
@@ -1441,11 +1446,12 @@ plot.replot_xts <- function(x, ...) {
  omar <- par(mar = x$Env$mar)
  oxpd <- par(xpd = FALSE)
  usr <- par("usr")
+ # reset par
  on.exit(par(xpd = oxpd$xpd, cex = ocex$cex, mar = omar$mar, bg = obg$bg))
 
  x$render_panels()
 
  do.call("clip", as.list(usr)) # reset clipping region
- # reset par
+
  invisible(x$Env$actions)
 }