Hello matplotlib developers,
I have implemented "svg.image_noscale" feature for ps and pdf backends. I think
that resampling/scaling should be avoided, when vector format can scale image
itself.
One advantage is that original image can be recovered from final file. Moreover
as it is vector format it should be dpi independent and always provide maximum
possible quality - that's original data.
As for svg backend I have commented some transformation changes which
I don't understand and which result in misaligned image and axes.
Without it the misalignment is still there but smaller.
I have also removed MixedModeRenderer from svg as it conflicts with "svg.image_noscale"
and does not seem to be used.
As last change, I restored commented self.figure.canvas.draw() in
FigureCanvasBase.print_figure as I got complaints about "I/O operation on
closed file" when I tried to "draw_artist" in my animation using blit
technique. (It used cached renderer that no longer existed,
self.figure.canvas.draw() updates this cache)
Further more please consider set_animated(False) on all artists before saving
hardcopy and restore animated state after (animated artist should be saved,
although they can not animate in hardcopy)
Thanks for reviewing my suggestions
Jozef Vesely
vesely@...670...
--- /usr/lib/python2.5/site-packages/matplotlib/backends/backend_svg.py 2008-08-03 20:15:03.000000000 +0200
+++ backend_svg.py 2008-11-12 10:08:54.000000000 +0100
@@ -254,9 +254,9 @@
transstr = ''
if rcParams['svg.image_noscale']:
trans = list(im.get_matrix())
- if im.get_interpolation() != 0:
- trans[4] += trans[0]
- trans[5] += trans[3]
+ #if im.get_interpolation() != 0:
+ # trans[4] += trans[0]
+ # trans[5] += trans[3]
trans[5] = -trans[5]
transstr = 'transform="matrix(%s %s %s %s %s %s)" '%tuple(trans)
assert trans[1] == 0
@@ -579,9 +579,9 @@
self.figure.set_dpi(72.0)
width, height = self.figure.get_size_inches()
w, h = width*72, height*72
···
-
- renderer = MixedModeRenderer(
- width, height, 72.0, RendererSVG(w, h, svgwriter, filename))
+
+
+ renderer = RendererSVG(w, h, svgwriter, filename)
self.figure.draw(renderer)
renderer.finalize()
if fh_to_close is not None:
--- backend_ps.py 2008-08-03 20:15:03.000000000 +0200
+++ backend_ps.py.new 2008-11-12 10:04:33.000000000 +0100
@@ -400,7 +400,13 @@
bbox is a matplotlib.transforms.BBox instance for clipping, or
None
"""
-
+ if rcParams['svg.image_noscale']:
+ trans = list(im.get_matrix())
+ numrows,numcols = im.get_size()
+ im.reset_matrix()
+ im.set_interpolation(0)
+ im.resize(numcols, numrows)
+
im.flipud_out()
if im.is_grayscale:
@@ -413,8 +419,12 @@
xscale, yscale = (
w/self.image_magnification, h/self.image_magnification)
-
- figh = self.height*72
+
+ if rcParams['svg.image_noscale']:
+ xscale *= trans[0]
+ yscale *= trans[3]
+
+ #figh = self.height*72
#print 'values', origin, flipud, figh, h, y
clip = []
--- backend_pdf.py 2008-08-03 20:15:03.000000000 +0200
+++ backend_pdf.py.new 2008-11-12 10:06:30.000000000 +0100
@@ -1226,9 +1226,17 @@
gc.set_clip_rectangle(bbox)
self.check_gc(gc)
+ if rcParams['svg.image_noscale']:
+ t = list(im.get_matrix())
+ numrows,numcols = im.get_size()
+ im.reset_matrix()
+ im.set_interpolation(0)
+ im.resize(numcols, numrows)
+
h, w = im.get_size_out()
imob = self.file.imageObject(im)
self.file.output(Op.gsave, w, 0, 0, h, x, y, Op.concat_matrix,
+ t[0],0,0,t[3],0,0, Op.concat_matrix,
imob, Op.use_xobject, Op.grestore)
def draw_path(self, gc, path, transform, rgbFace=None):
--- /usr/lib/python2.5/site-packages/matplotlib/backend_bases.py 2008-08-03 20:15:03.000000000 +0200
+++ backend_bases.py 2008-11-12 10:22:38.000000000 +0100
@@ -1313,7 +1313,7 @@
self.figure.set_facecolor(origfacecolor)
self.figure.set_edgecolor(origedgecolor)
self.figure.set_canvas(self)
- #self.figure.canvas.draw() ## seems superfluous
+ self.figure.canvas.draw() ## not superfluous
return result
def get_default_filetype(self):