Incorrect json representation for graphics

[fchapoton]

see https://groups.google.com/forum/#!topic/sage-devel/Wjo7NkmvCks

The problem lies in the file src/sage/plot/plot3d/index_face_set.pyx, where the json is generated. There are two problems with the generated json:

1. The quote signs used in the file are ' and not " as per Json spec.

2. Every dictionary key is unquoted, which is incorrect. Thus, a point

   {x:0,y:0,z:0}

   should really be

   {"x":0,"y":0,"z":0}

   as per Json spec.

CC: @novoselt @egourgoulhon

Component: graphics

Author: Frédéric Chapoton

Branch/Commit: fbd8b10

Reviewer: Paul Masson

Issue created by migration from https://trac.sagemath.org/ticket/22253

[fchapoton]

Commit: 9a7269f

[fchapoton]

Branch: u/chapoton/22253

[fchapoton]

Description changed:

--- 
+++ 
@@ -1 +1,15 @@
 see https://groups.google.com/forum/#!topic/sage-devel/Wjo7NkmvCks
+
+
+The problem lies in the file `src/sage/plot/plot3d/index_face_set.pyx`, where the json is generated. There are two problems with the generated json:
+
+1. The quote signs used in the file are `'` and not `"` as per [Json spec](http://www.ecma-international.org/publications/files/ECMA-ST/ECMA-404.pdf).
+2. Every dictionary key is unquoted, which is incorrect. Thus, a point 
+    
+        {x:0,y:0,z:0}
+        
+    should really be
+
+        {"x":0,"y":0,"z":0}
+        
+    as per Json spec.

[fchapoton]

Author: Frédéric Chapoton

[fchapoton]

New commits:

9a7269f

trac 22253 fixing json repr of index_face_set

[7ed8c4ca-6d56-4ae9-953a-41e42b4ed313]

Changed commit from 9a7269f to 5f7e950

[7ed8c4ca-6d56-4ae9-953a-41e42b4ed313]

Branch pushed to git repo; I updated commit sha1. New commits:

5f7e950

trac 22253 fix doctests

[7ed8c4ca-6d56-4ae9-953a-41e42b4ed313]

Branch pushed to git repo; I updated commit sha1. New commits:

11e4447

trac 22253 fix more doctests

[7ed8c4ca-6d56-4ae9-953a-41e42b4ed313]

Changed commit from 5f7e950 to 11e4447

[fchapoton]

comment:4

Seems ok with the canvas3d viewer (in sagenb):

sage: u,v = var('u,v')
sage: def cf(u,v): return sin(u+v/2)**2
sage: P = parametric_plot3d((cos(u), sin(u)+cos(v), sin(v)),
....: (u,0,2*pi), (v,-pi,pi), color=(cf,colormaps.PiYG), plot_points=[60,60])
sage: P.show(viewer='canvas3d')

Needs to be tested in other kinds of notebooks.

Ok also in jupyter notebook. Remains to check in cloud (not that easy).

[53959995-fd20-47f5-85e6-5e769b863d1f]

comment:5

All doctests pass in sage/plot/plot3d. Works with the new native Three.js viewer.

I would like to point out that this modification will bloat Three.js files without any change to the rendering, since JavaScript doesn't care whether array keys are quoted or not. Presumably that was part of the motivation for using formally incorrect JSON to begin with, so I didn't change it when writing the Three.js viewer.

[53959995-fd20-47f5-85e6-5e769b863d1f]

Reviewer: Paul Masson

[7ed8c4ca-6d56-4ae9-953a-41e42b4ed313]

Changed commit from 11e4447 to d04e1b5

[7ed8c4ca-6d56-4ae9-953a-41e42b4ed313]

Branch pushed to git repo; I updated commit sha1. New commits:

e98721d	Merge branch 'u/chapoton/22253' in 7.6.b1
d04e1b5	trac 22253 one more detail

[fchapoton]

comment:7

one still needs to change

local/share/sage/ext/doctest/rich_output/example.canvas3d

but this is not under git control ?

[fchapoton]

comment:8

Attachment: example.canvas3d.gz

I have attached the modified example file. What now ?

[7ed8c4ca-6d56-4ae9-953a-41e42b4ed313]

Branch pushed to git repo; I updated commit sha1. New commits:

061c579	Merge branch 'u/chapoton/22253' in 7.6.b3
969685a	trac 22253 fixing the canvas3d example file

[7ed8c4ca-6d56-4ae9-953a-41e42b4ed313]

Changed commit from d04e1b5 to 969685a

[fchapoton]

comment:10

This should be good now, but patchbots will not have a look. Please check and review.

[53959995-fd20-47f5-85e6-5e769b863d1f]

comment:11

Failing doctest from most recent alterations:

File "src/sage/repl/rich_output/output_graphics3d.py", line 159, in sage.repl.rich_output.output_graphics3d.OutputSceneCanvas3d.example
Failed example:
    rich_output.canvas3d
Expected:
    buffer containing 649 bytes
Got:
    buffer containing 829 bytes

[7ed8c4ca-6d56-4ae9-953a-41e42b4ed313]

Branch pushed to git repo; I updated commit sha1. New commits:

111dfe2	Merge branch 'u/chapoton/22253' in 7.6.b4
fbd8b10	trac 22253 fixing doctest, plus remove trailing whitespaces

[7ed8c4ca-6d56-4ae9-953a-41e42b4ed313]

Changed commit from 969685a to fbd8b10

[fchapoton]

comment:13

done, should be good now.

[vbraun]

Changed branch from u/chapoton/22253 to fbd8b10