Have subplot() reanchor image axis references, closes #1332

Author: cpsievert

R/subplots.R

@@ -63,7 +63,7 @@
 subplot <- function(..., nrows = 1, widths = NULL, heights = NULL, margin = 0.02, 
                     shareX = FALSE, shareY = FALSE, titleX = shareX, 
                     titleY = shareY, which_layout = "merge") {
- 
+  
 
   plots <- dots2plots(...)
 
@@ -215,16 +215,25 @@ subplot <- function(..., nrows = 1, widths = NULL, heights = NULL, margin = 0.02
       axisMap <- setNames(sub("axis", "", axisMap), sub("axis", "", names(axisMap)))
       newAnchors <- names(axisMap)[match(oldAnchors, axisMap)]
       traces[[i]] <- Map(function(tr, a) { tr[[key]] <- a; tr }, traces[[i]], newAnchors)
-      # also map annotation[i].xref/annotation[i].yref
+      # also map annotation and image xaxis/yaxis references
+      # TODO: do this for shapes as well?
       ref <- list(xaxis = "xref", yaxis = "yref")[[key]]
       if (is.null(ref)) next
-      if (is.null(annotations[[i]])) next
-      annotations[[i]] <- Map(function(ann, a) { 
-        if (!identical(ann[[ref]], "paper")) ann[[ref]] <- a
-        ann
-      }, annotations[[i]], newAnchors)
+      if (length(annotations[[i]])) {
+        annotations[[i]] <- Map(function(x, y) { 
+          if (!identical(x[[ref]], "paper")) x[[ref]] <- y 
+          x
+        }, annotations[[i]], newAnchors)
+      }
+      if (length(images[[i]])) {
+        images[[i]] <- Map(function(x, y) { 
+          if (!identical(x[[ref]], "paper")) x[[ref]] <- y 
+          x
+        }, images[[i]], newAnchors)
+      }
     }
 
+    
     # rescale domains according to the tabular layout
     xDom <- as.numeric(domainInfo[i, c("xstart", "xend")])
     yDom <- as.numeric(domainInfo[i, c("yend", "ystart")])

tests/testthat/test-plotly-subplot.R

@@ -199,6 +199,39 @@ test_that("images accumulate and paper coordinates are repositioned", {
   expect_true(imgs[[2]]$sizey == 0.5)
 })
 
+test_that("images axis references are remapped", {
+  
+  r <- as.raster(matrix(hcl(0, 80, seq(50, 80, 10)), nrow = 4, ncol = 5))
+  
+  # embed the raster as an image
+  p <- plot_ly(x = 1, y = 1) %>% 
+    layout(
+      images = list(list(
+        source = raster2uri(r),
+        sizing = "fill",
+        xref = "x", 
+        yref = "y", 
+        x = 0, 
+        y = 0, 
+        sizex = 1, 
+        sizey = 1, 
+        xanchor = "left", 
+        yanchor = "bottom"
+      ))
+    )
+  
+  s <- subplot(p, p, nrows = 1, margin = 0.02)
+  imgs <- plotly_build(s)$x$layout$images
+  expect_true(imgs[[1]]$x == 0)
+  expect_true(imgs[[1]]$y == 0)
+  expect_true(imgs[[1]]$xref == "x")
+  expect_true(imgs[[1]]$yref == "y")
+  expect_true(imgs[[2]]$x == 0)
+  expect_true(imgs[[2]]$y == 0)
+  expect_true(imgs[[2]]$xref == "x2")
+  expect_true(imgs[[2]]$yref == "y2")
+})
+
 
 
 test_that("geo+cartesian behaves", {