# HG changeset patch
# User Rik <rik@octave.org>
# Date 1382138864 25200
# Node ID 38cf56b77274504c79b9b8ac8a1c4bbc59d1dfe5
# Parent  8a54a481ecb5ee9709202b9d9d3abda2c6724980
Overhaul image, imagesc to use newplot and support low-level invocation form.

* scripts/image/image.m: New variable do_new indicates high-level calling form.
For high-level invocation, call newplot before __img__.  Correct linearity check
if vectors are reversed (high-to-low values).  Only apply image properties to axes
if doing a high-level invocation.

* scripts/image/imagesc.m: New variable do_new indicates high-level calling form.
Delete subfunction __imagesc__ and incorporate minimal amount of code into imagesc.
Only apply climits for high-level invocation.

diff -r 8a54a481ecb5 -r 38cf56b77274 scripts/image/image.m
--- a/scripts/image/image.m	Fri Oct 18 23:44:44 2013 +0200
+++ b/scripts/image/image.m	Fri Oct 18 16:27:44 2013 -0700
@@ -65,15 +65,31 @@
 
   [hax, varargin, nargin] = __plt_get_axis_arg__ ("image", varargin{:});
   
-  if (isempty (hax))
-    hax = gca ();
-  endif
-
   chararg = find (cellfun ("isclass", varargin, "char"), 1, "first");
   
-  if (nargin == 0 || chararg == 1)
+  do_new = true;
+  if (nargin == 0)
     img = imread ("default.img");
     x = y = [];
+  elseif (chararg == 1) 
+    ## Low-Level syntax
+    do_new = false;
+    x = y = img = [];
+    idx = find (strcmpi (varargin, "cdata"), 1);
+    if (idx)
+      img = varargin{idx+1};
+      varargin(idx:idx+1) = [];
+    endif
+    idx = find (strcmpi (varargin, "xdata"), 1);
+    if (idx)
+      x = varargin{idx+1};
+      varargin(idx:idx+1) = [];
+    endif
+    idx = find (strcmpi (varargin, "ydata"), 1);
+    if (idx)
+      y = varargin{idx+1};
+      varargin(idx:idx+1) = [];
+    endif
   elseif (nargin == 1 || chararg == 2)
     img = varargin{1};
     x = y = [];
@@ -85,9 +101,25 @@
     img = varargin{3};
     chararg = 4;
   endif
-  
-  htmp = __img__ (hax, x, y, img, varargin{chararg:end});
-  set (hax, "layer", "top");
+
+  oldfig = [];
+  if (! isempty (hax))
+    oldfig = get (0, "currentfigure");
+  endif
+  unwind_protect
+    if (do_new)
+      hax = newplot (hax);
+    elseif (isempty (hax))
+      hax = gca ();
+    endif
+
+    htmp = __img__ (hax, do_new, x, y, img, varargin{chararg:end});
+
+  unwind_protect_cleanup
+    if (! isempty (oldfig))
+      set (0, "currentfigure", oldfig);
+    endif
+  end_unwind_protect
 
   if (nargout > 0)
     h = htmp;
@@ -105,89 +137,89 @@
 ## Created: July 1994
 ## Adapted-By: jwe
 
-function h = __img__ (hax, x, y, img, varargin)
-
-  if (isempty (img))
-    error ("__img__: matrix is empty");
-  endif
+function h = __img__ (hax, do_new, x, y, img, varargin)
 
   ## FIXME: Hack for integer formats which use zero-based indexing
   ##        Hack favors correctness of display over size of image in memory.
-  ##        True fix will be done in C++ code. 
+  ##        True fix must be done in C++ code for renderer. 
   if (ndims (img) == 2 && (isinteger (img) || islogical (img)))
     img = single (img) + 1;
   endif
 
-  if (isempty (x))
-    x = [1, columns(img)];
-  endif
+  if (! isempty (img))
+
+    if (isempty (x))
+      x = [1, columns(img)];
+    endif
 
-  if (isempty (y))
-    y = [1, rows(img)];
-  endif
+    if (isempty (y))
+      y = [1, rows(img)];
+    endif
 
-  xdata = x([1, end]);
-  ydata = y([1, end]);
+    xdata = x([1, end]);
+    ydata = y([1, end]);
 
-  if (numel (x) > 2 && numel (y) > 2)
-    ## Test data for non-linear spacing which is unsupported
-    tol = .01;  # 1% tolerance.  FIXME: this value was chosen without thought.
-    dx = diff (x);
-    dxmean = (max (x) - min (x)) / (numel (x) - 1);
-    dx = abs ((dx - dxmean) / dxmean);
-    dy = diff (y);
-    dymean = (max (y) - min (y)) / (numel (y) - 1);
-    dy = abs ((dy - dymean) / dymean);
-    if (any (dx > tol) || any (dy > tol))
-      warning ("image: non-linear X, Y data is ignored.  IMG will be shown with linear mapping");
+    if (numel (x) > 2 && numel (y) > 2)
+      ## Test data for non-linear spacing which is unsupported
+      tol = .01;  # 1% tolerance.  FIXME: this value was chosen without thought.
+      dx = diff (x);
+      dxmean = (max (x) - min (x)) / (numel (x) - 1);
+      dx = abs ((abs (dx) - dxmean) / dxmean);
+      dy = diff (y);
+      dymean = (max (y) - min (y)) / (numel (y) - 1);
+      dy = abs ((abs (dy) - dymean) / dymean);
+      if (any (dx > tol) || any (dy > tol))
+        warning (["image: non-linear X, Y data is ignored.  " ...
+                  "IMG will be shown with linear mapping"]);
+      endif
     endif
-  endif
+
+  endif  # ! isempty (img)
 
-  htmp = __go_image__ (hax, "cdata", img, "xdata", xdata, "ydata", ydata,
-                       "cdatamapping", "direct", varargin {:});
+  h = __go_image__ (hax, "cdata", img, "xdata", xdata, "ydata", ydata,
+                         "cdatamapping", "direct", varargin{:});
 
-  px = __image_pixel_size__ (htmp);
+  if (do_new && ! ishold (hax))
+    ## Set axis properties for new images
 
-  if (xdata(2) < xdata(1))
-    xdata = fliplr (xdata);
-  elseif (xdata(2) == xdata(1))
-    xdata = xdata(1) + [0, columns(img)-1];
-  endif
-  if (ydata(2) < ydata(1))
-    ydata = fliplr (ydata);
-  elseif (ydata(2) == ydata(1))
-    ydata = ydata(1) + [0, rows(img)-1];
-  endif
-  xlim = xdata + [-px(1), px(1)];
-  ylim = ydata + [-px(2), px(2)];
+    if (! isempty (img))
+      px = __image_pixel_size__ (h);
+
+      if (xdata(2) < xdata(1))
+        xdata = fliplr (xdata);
+      elseif (xdata(2) == xdata(1))
+        xdata = xdata(1) + [0, columns(img)-1];
+      endif
+      if (ydata(2) < ydata(1))
+        ydata = fliplr (ydata);
+      elseif (ydata(2) == ydata(1))
+        ydata = ydata(1) + [0, rows(img)-1];
+      endif
+      xlim = xdata + [-px(1), px(1)];
+      ylim = ydata + [-px(2), px(2)];
 
-  ## FIXME -- how can we do this and also get the {x,y}limmode
-  ## properties to remain "auto"?  I suppose this adjustment should
-  ## happen automatically in axes::update_axis_limits instead of
-  ## explicitly setting the values here.  But then what information is
-  ## available to axes::update_axis_limits to determine that the
-  ## adjustment is necessary?
-  set (hax, "xlim", xlim, "ylim", ylim);
+      ## FIXME -- how can we do this and also get the {x,y}limmode
+      ## properties to remain "auto"?  I suppose this adjustment should
+      ## happen automatically in axes::update_axis_limits instead of
+      ## explicitly setting the values here.  But then what information is
+      ## available to axes::update_axis_limits to determine that the
+      ## adjustment is necessary?
+      set (hax, "xlim", xlim, "ylim", ylim);
 
-  if (ndims (img) == 3)
-    if (isinteger (img))
-      cls = class (img);
-      mn = intmin (cls);
-      mx = intmax (cls);
-      set (hax, "clim", double ([mn, mx]));
-    endif
-  endif
+      if (ndims (img) == 3)
+        if (isinteger (img))
+          cls = class (img);
+          mn = intmin (cls);
+          mx = intmax (cls);
+          set (hax, "clim", double ([mn, mx]));
+        endif
+      endif
 
-  set (hax, "view", [0, 90]);
+    endif  # ! isempty (img)
 
-  if (strcmp (get (hax, "nextplot"), "replace"))
-    ## Always reverse y-axis for images, unless hold is on
-    set (hax, "ydir", "reverse");
-  endif
+    set (hax, "view", [0, 90], "ydir", "reverse", "layer", "bottom");
 
-  if (nargout > 0)
-    h = htmp;
-  endif
+  endif  # do_new
 
 endfunction
 
@@ -212,3 +244,4 @@
 %!  h = image (-x, -y, img);
 %!  title ("image (-x, -y, img)");
 
+## FIXME: Need %!tests for linear
diff -r 8a54a481ecb5 -r 38cf56b77274 scripts/image/imagesc.m
--- a/scripts/image/imagesc.m	Fri Oct 18 23:44:44 2013 +0200
+++ b/scripts/image/imagesc.m	Fri Oct 18 16:27:44 2013 -0700
@@ -52,23 +52,66 @@
 
 function h = imagesc (varargin)
 
-  if (nargin < 1 || nargin > 4)
+  [hax, varargin, nargin] = __plt_get_axis_arg__ ("imagesc", varargin{:});
+
+  chararg = find (cellfun ("isclass", varargin, "char"), 1, "first");
+
+  do_new = true;
+  if (nargin == 0)
     print_usage ();
-  elseif (isscalar (varargin{1}) && ishandle (varargin{1}))
-    hax = varargin{1};
-    if (! isaxes (hax))
-      error ("imagesc: HAX argument must be an axes object");
+  elseif (chararg == 1)
+    ## Low-Level syntax
+    do_new = false;
+    img = x = y = climits = [];
+  elseif (nargin == 1 || chararg == 2)
+    img = varargin{1};
+    x = y = climits = [];
+  elseif (nargin == 2 || chararg == 3)
+    img = varargin{1};
+    climits = varargin{2};
+    x = y = [];
+  elseif (nargin == 3 || chararg == 4)
+    x = varargin{1};
+    y = varargin{2};
+    img = varargin{3};
+    climits = [];
+  elseif (nargin == 4 || chararg == 5)
+    x = varargin{1};
+    y = varargin{2};
+    img = varargin{3};
+    climits = varargin{4};
+  endif
+
+  oldfig = [];
+  if (! isempty (hax))
+    oldfig = get (0, "currentfigure");
+  endif
+  unwind_protect
+    if (do_new)
+      hax = newplot (hax);
+    elseif (isempty (hax))
+      hax = gca ();
     endif
-    oldh = gca ();
-    unwind_protect
-      axes (h);
-      htmp = __imagesc__ (hax, varargin{2:end});
-    unwind_protect_cleanup
-      axes (oldh);
-    end_unwind_protect
-  else
-    htmp = __imagesc__ (gca (), varargin{:});
-  endif
+
+    if (do_new)
+      htmp = image (x, y, img, "cdatamapping", "scaled", varargin{chararg:end});
+    else
+      htmp = image ("cdatamapping", "scaled", varargin{:});
+    endif
+
+    if (do_new && ! ishold (hax))
+      ## use given climits or guess them from the matrix
+      if (numel (climits) == 2 && climits(1) <= climits(2))
+        set (hax, "clim", climits);
+      elseif (! isempty (climits))
+        error ("imagesc: CLIMITS must be in form [lo, hi]");
+      endif
+    endif
+  unwind_protect_cleanup
+    if (! isempty (oldfig))
+      set (0, "currentfigure", oldfig);
+    endif
+  end_unwind_protect
 
   if (nargout > 0)
     h = htmp;
@@ -76,31 +119,6 @@
 
 endfunction
 
-function h = __imagesc__ (ax, x, y, img, climits)
-
-  if (nargin == 2)
-    img = x;
-    x = y = climits = [];
-  elseif (nargin == 3)
-    img = x;
-    climits = y;
-    x = y = [];
-  elseif (nargin == 4 && ! isscalar (x) && ! isscalar (y) && ! isscalar (img))
-    climits = [];
-  endif
-
-  h = image (ax, x, y, img);
-  set (h, "cdatamapping", "scaled");
-
-  ## use given climits or guess them from the matrix
-  if (numel (climits) == 2 && climits(1) <= climits(2))
-    set (ax, "clim", climits);
-  elseif (! isempty (climits))
-    error ("imagesc: CLIMITS must be in form [lo, hi]");
-  endif
-
-endfunction
-
 
 %!demo
 %! clf;