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When printing with a scale, eg. 1:10, line-widths are scaled too. They should not. 1) they become very faint in the printout, 2) line-width in CAD carries extra information (Andrew told me:)

- Draw a rectangle, say 100 x 100 (I use mm unit, but does it matter?)
1
- Turn on print preview
- Turn off print preview
- OK
2
- Turn on print preview
- Set scale 1/10
- Lines are thicker now, this is good
- Turn off print previw
- Lines stay thick in model view, should that be so?
3
- Set layer 0 to use dash as line-style
- Turn on print preview
- Looks OK
- Set scale 1/10
- Dashes hardly visible, looks almost like a continuous line

In the end of 2,3 a way to reset line width display in model view is to cancel scaling in print preview, ie. turn on print preview, set scale 1:1. I suppose this is a regression since TP1: model view always is unscaled.

The line-width scaling is quite accurate now: Draw two lines 10 mm apart. Set line-width 0.5mm. Set scale 1:20 and the lines exactly touch.

Reading  FS#441  I fired up the Library Browser, which works fine here, RC2 from tgz on Ubuntu 10.04, BTW.

The freedxf.com drawings “horseman” and two “women” claim to be “Creative Commons Attribution-NonCommercial-ShareAlike 3.0”. In my opinion, the “NonCommercial” clause does prohibit distribution in QCAD3, which is a commercial package. For a discussion see http://wiki.creativecommons.org/Defining_Noncommercial

Something with hatching changed between 3.10 and 3.12; Changelog for 3.11.2 states: “Add support for hatch patterns defined per entity”. That may be?

Attached drawing from an older version; open in current and see a black box where there should be earth. Change scaling of hatch from 10 to 254 and it will be exactly the same it was when saving the file.

Curiously, that is like swapping inches and mm? Looking into prefs, there is a new drop down: “Messsytem für Linien und Schraffuren” and it read “imperial”; making it metric and bingo, my drawing looks as intended!

This is bad, because each drawing has to be changed! I changed the application default drawing setting to metric and the existing drawing still had imperial set…

Probably a heuristic was on order? If the drawing does not specify the new setting, and the drawing units is metric, use metric?

As of TP1, a script once loaded into the runtime, does reflect changes to the file it was loaded from only after a restart of the whole of QCAD. This adds a considerable time overhead to developing scripts. Therefore I want to suggest a reload mechanism, that works kind of like the one known from a web browser.

As there is no clear separation between users custom scripts and ribbonsoft supplied scripts, checking the modification time for every access to any script might prove a performance hit.

Possibly a user script can be written, to invalidate another certain script and have the runtime reload it from file? I could add that to my menu.

Or as some magic, that can be written to “MyAction.init()”?

Rationale:

Let QCAD handle extended entity data, that is used in the industry to instruct postprocessing applications, e.g. the tooling of a mill or robot.

When I say group code or specs below, I refer to this document http://www.autodesk.com/techpubs/autocad/acad2000/dxf/extended_data_dxf_ab.htm

Current:

In the property editor I can add key value pairs to drawing entities. As in this script:

entity.setProperty(new RPropertyTypeId("MY_KEY"), "MY_VAL");
entity.setProperty(new RPropertyTypeId("MY_REAL"), 123);

In DXF this results in a group code “QCAD” followed by alternating keys and values as strings and typed positions respectively:

[…]
  0
LINE
[…]
1001
QCAD
1000
MY_KEY
1000
MY_VAL
1000
MY_REAL
1040
123.0
[…]

Expected:

From reading the specs, this looks perfectly valid. I’d say though, that QCAD is not right to expect any extended data to follow this pattern. The extended entity data, that I want to recreate eg, looks like this:

[…]
  0
LINE
[…]
1001
MY_DATA
1000
MY_FOO: some text
1000
MY_BAR: 1.250000
[…]

That is: a group code, followed by some string values. Notice that the (limited) typing facilities mentioned in the spec are not used, but the application relies on its own peculiar parsing. The same group code appears in the head of the document as an APPID:

[…]
  0
APPID
  2
MY_DATA
 70
     0
  0
[…]

Proposed:

I suggest, that QCAD uses APPIDs to group extended data. Otherwise data loss may occur. In order to not have to maintain a table of known APPIDs, that tells how to parse their extended data, I further suggest that QCAD not expect extended data to follow a “key value” pattern but an “APPID entries” pattern. Here too data would be lost, if there was an odd number of entries in the extended table and QCAD insisted on its own approach.

Within the specs, deep trees could be constructed with the use of the control string (code 1002, { and }), and the propertyEditor would become a nightmare;) So I propose, that QCAD might parse only extended data with its own APPID in key value pairs, and data with other APPIDs as just an ordered list of entries. (In ECMAscript an array will have to be used, as object properties do not keep sequence.)

In scripting hatchData.addBoundary can use any shape, but only some actually produce something useful, eg. this fails silently:

"ANSI31"

Shouldn’t an exception be thrown?

A hatch my have “holes”, if it eg. is made of two forms, an inner form, and and outer form, where the outer form is filled while the inner form appears like a window inside of the fill, that lets the background be seen.

QCAD exports such hatches as two SVG paths in one single entity. But the “hole” is lost in the process. I know of two workarounds, that preserve the original intention of the QCAD drawing, both get the same result most of the time, the second one looking more robust and easier to implement:

# draw the outer form clockwise, draw the inner form counterclockwise
# set the “fill-rule:evenodd” attribute on the fill definition of the entity

Drawing a star like in the SVG spec in QCAD actually produces the same picture – so that should be the way to go.

http://www.w3.org/TR/SVG/painting.html#FillRuleProperty

In DXF world, as far as I know, colour 7 - white - is magic, in that it shows white in model space on a black background, possibly also black on a light background, and commonly black in paper space irrespectively of background colour. In my opinion, SVG should be considered paper space.

I propose, that white entities get rendered black in SVG files exported from QCAD. What do you think?

The QCAD scripts, that contain a great deal of functionality in the QCAD framework, are so to say open source, in the limited, still powerful, sense that they can be read, inspected and single-handedly adapted to local needs. Wouldn’t it make sense to store these in a public source code repository?

So to allow closer tracking of development, eg. Of course, all of the scripts would then have to know which release of the /kernel/ they require as a support. But that should be a good thing anyways, as soon as a community of framework users arises, wasn’t it?

QCAD 3 TP1 cannot export to PNG (or any other bitmap format). QCAD 2 lets set width and height in pixels of the file to be created. The drawing is then scaled proportionally to fit that. Leaving the height value empty will crash QCAD 2. QCAD 2 will also pad the image with an unspecified value that gets (both absolutely and relatively) smaller when the size increases…

QCAD 2 interface is simple and should meet most users needs. It would be nice to calculate the missing value, if only width or height is set. Some padding might be necessary only when antialiasing is done on export.

Setting scale and DPI instead would require more thinking on users side…

In files exported with the (even PG) exporter I sometimes see values like these: 334.99999999999994 or 570.0000000000001 and very often 12 digits of precision.

To safe on file size, I suggest, that QCAD rounds values on SVG export to eg. three places. When viewed in an ordinary web browser, that will result in a precision of 1 inch / 96dpi / 1000 = 0.00026mm, not? Ends should still meet.

If I understand correctly, SVG export uses svg groups to keep QCAD block entities. This in itself is very useful. There is no way to correctly keep layer information, as QCAD blocks can contain elements on different layers, while SVG only knows about groups. That is a deficiency of SVG.

To save on file size, there was some potential to get rid of ever repeating same attributes on entities, eg: style=”stroke:#000000;stroke-width:0.25;stroke-dasharray:2.16,1.08”

To optimize “By Block” is easy: just set the attribute on the SVG group, and omit on below entities styled “By Block”.

To optimize “By Layer” is a little more involved, but might be solved by using css:
- Create a class by the name of the Layer
- add the class attribute to elements styled “By Layer”

Then only individually styled entities would get a style attribute, and filesize of SVG could be halved in most cases.

This just an idea :) Having written this, I now realize, that QCAD can style weight, pattern, color each extra, so the optimazition could only be applied to entities, where everything is “By Layer” or “By Block”. But that should be the case most of the time.

Dimension labels in QCAD are (always?) centered on the dimension line, while in exported SVGs the text starts from the center and extends into the writing direction. This can trivially be fixed by adding the attribute “text-anchor:middle” to the respective SVG “text” nodes.

QCAD offers horizontal and vertical alignment choices for text. This is not carried over to PG exported SVGs. Currently QCAD sets the “dy” attribute on text nodes in a way, such that any text in SVG will look like the QCAD vertical alignment was set to “Top” and the horizontal one to “Left”.

Naively one can just omit the “dy” attribute and in SVG this will look like the QCAD vertical alignment was set to “bottom”. At least for single line texts that should be good.

The horizontal alignments can be recreated in SVG with the “text-anchor” attribute for text nodes. The values “start”, “middle” and “end” correspond to the QCAD “left”, “center” and “right” choices.

When PG exporting to SVG, stroke-widths are scaled with the drawing, while they should not.

The SVG PG exporter does not scale hatches.

Text scaling in PG SVG exporter is missing just two small additions: These attributes are not taken care of by now:

font-size, dy

Just use the current value times scale: eg 2.5 * 0.1 to have a scale of 1:10. Looks good here.

Points are not scaled when PG exported to SVG:

Points as crosses are created eg. like this:

d=m 2.5,3 1,0 M 3,2.5 l 0,1

and in SVG look fine like that (scale 1/10):

d=m 2.95,3 0.1,0 M 3,2.95 3,3.05

stroke-width should be left unchanged.

SVG PG exporter, scaled or unscaled, currently only exports the labels of dimensions. Missing are

ticks, arrows, and lines of the dimension.

It will not be as simple as inkscape does it, wrap it all in a <def>.

In print preview lines are correctly scaled to stay the same width when printed, ie 0.25 or so mm thick. Print preview shows that very good.

But the round line-caps mess up the display, as in small scale the line-caps start to meet and make the line look like a continous one.

Print preview should not only correct line weight but also line patterns, so that the distance between dashes increase by scale.

White text gets exported as white text, while it should be exported as black text. Just like it is with lines. Attached patch makes text rendering use the conversion function that is already in the code base.

Font styles “bold” and “italic” are not saved to file.

According to http://docs.autodesk.com/ACD/2011/DEU/filesDXF/WS1a9193826455f5ff18cb41610ec0a2e719-7a4d.htm it is saved in dxf as group code 1071 and according to http://www.autodesk.com/techpubs/autocad/dxf/dxf2002.pdf page 20 its type is “Extended data 32-bit signed long”.

Patch to PG export font styles “bold” and “italic” to SVG. (This only works when a file with the right style is loaded into QCAD, as QCAD will yank such style information upon saving.)

I noticed like this:

in a block pasted from the library, text would be under differently coloured lines, although it should be above them, and this does not look nice.

Drawing order inside of a block should not be changed by a paste operation, not?

Both SvgExporters ignore the exportPoints setting. Attached patch takes care of that. To be applied from within the “scripts” directory.

Nitpicking in File/SvgExport/SvgExport.js, var properties is meant to be a plain Object instead of an Array, isn’t it?

DWG files created with QCAD display really fine now in autocad. There are only two minor issues for ACAD users:

1) ACAD complains, that they were not created with a licensed application. One may not be able to work around that one...

2) ACAD complains, that the file does not specify a codepage. For this one, there should be a way around, shouldn’t it?

I am very happy with the compatibility in the new QCAD. Thank you very much for all the efforts that went into it!

Peter

Snap defaults to auto. Auto snap gets slow in areas where there are many places it can snap to.

Select → Contour (T, C) and click into empty space, will cause an exception, REntityPointer being a null pointer (0×0) and not false, undefined or something like that.

When many tabs are open, the name of contained drawing is not fully shown. One way that some mdi applications do, is to append the name of the active tab to the top window title, which is also useful in other ways. At least a tool tip with the full name of the file on the tab top was nice.

One can draw in print preview. If one does, QCAD starts acting confused, the model view gets restored with a fullbright white background.

Maybe best is to just disable all drawing and measuring in print preview?

It was nice to specify the default Format for saving files. 2010 is too young for distribution to unknown users, better use 2004 or so...

Sometimes the text of a dimension (that is in a block - just a suspicion of mine) will not get rotated. I do not know why this.text.getAngle() sometimes returns a wrong value, but there is a simple workaround: always rotate the text with the dimension:

--- SvgExporterPG-orig.js	2011-09-15 23:11:40.000000000 +0200
+++ SvgExporterPG.js	2011-10-07 13:07:03.715374911 +0200

@@ -428,9 +427,7 @@
         // dimension entity: export text:
         this.writeEntityComment(entity);
         this.text = entity.getTextData();
-//        var angle = this.text.getAngle();
-//        var offset = RVector.createPolar(this.text.getHeight()/2, angle + Math.PI/2);
-//        this.text.move(offset);
+        this.text.setAngle(entity.getAngle());
         this.textColor = entity.getColor();
         this.exportText();
         this.text = undefined;

Chat from  FS#194  singled out, so that can be closed.

Dash patterns in BETA2 are very much out of proportion. BETA2 always PG exports 1:1 and only scales strokes so that in the final rendering they match what a technical drawing would show. As dash patterns depend on stroke, both current stroke and final scale have to be brought in accord.

The patch below also restores the alignment of dashes, so that dashed lines do not end in a gap, at least in most occasions.

--- SvgExporterPG-orig.js	2011-09-15 23:11:40.000000000 +0200
+++ SvgExporterPG.js	2011-10-07 13:28:04.085376719 +0200
@@ -384,32 +384,29 @@
         continuous = true;
     }
     if (!continuous) {
-        //p.scale(this.getPatternFactor());
-        p.scale(1/this.scale);
+        // dash and gap lengths are to be proportional to line weight
+        // beware: line weight unit is 100 times millimeters, convert to current unit
+        // beware: the viewer scales lengths differently from weight
+        p.scale(RUnit.convert(this.weight / 100.0, RS.Millimeter, this.svgUnit) / this.scale);
         var num = p.getNumDashes();
-        var str = "";
+        var str = [];
         for ( var i = 0; i < num; ++i) {
             var len = Math.abs(p.getDashLengthAt(i));
-            // see FS#192:
-            //len = this.convert(len);
-            str += "" + len;
-            if (i < num - 1) {
-                str += ",";
-            }
-        }
-        additionalStyles += "stroke-dasharray:" + str;
-        
-        // does more harm than good
-//        if (isShape(this.shape)) {
-//            var length = this.shape.getLength();
-//            if (isNaN(this.offset)) {
-//                this.offset = this.getPatternOffset(length, p);
-//            } else {
-//                var num = Math.ceil(this.offset / p.getPatternLength());
-        //                this.offset -= num * p.getPatternLength();
-        //            }
-        //            additionalStyles += ";stroke-dashoffset:" + this.offset;
-        //        }
+            str.push(len);
+        }
+        additionalStyles += "stroke-dasharray:" + str.join(",");
+
+        // center dash-array
+        if (isShape(this.shape) && isFinite(this.shape.getLength())) {
+            var length = this.shape.getLength();
+            if (isNaN(this.offset)) {
+                this.offset = -this.getPatternOffset(length, p);
+            } else {
+                var num = Math.ceil(this.offset / p.getPatternLength());
+                this.offset -= num * p.getPatternLength();
+            }
+            additionalStyles += ";stroke-dashoffset:" + this.offset;
+        }
     }

A polyline or polygon created from segments always ends up in layer 0, shouldn’t it stay in the same layer as the segments have been?

Polylines may consist of lines and arcs. The SVG PG exporter writes them as all straight lines. A better mapping than polyline then was path, as is done with arcs now.

Starting qcad Beta 3 with command line argument -always-load-scripts will bring up debugger:

Uncaught exception at /opt/qcad-3.0.0-beta3-prof-linux/scripts/library.js:2: RangeError: Maximum call stack size exceeded.
2 include(”sprintf.js”);

The labels of dimensions in PG exporter are moved half text-height. Thats a bit much, and actually, no such movement looks more true to the display of same in QCAD itself.

--- SvgExporterPG.js.orig	2011-10-15 18:57:29.994666881 +0200
+++ SvgExporterPG.js	2011-10-15 18:57:39.284666834 +0200
@@ -434,7 +434,7 @@
         //debugger;
         var angle = this.text.getAngle();
         //this.text.setAngle(entity.getAngle());
-        var offset = RVector.createPolar(this.text.getHeight()/2, angle + Math.PI/2);
+        var offset = RVector.createPolar(0, angle + Math.PI/2);
         this.text.move(offset);
         this.textColor = entity.getColor();
         this.exportText();

The capability of running headless, ie. without GUI, is a very welcome addition to QCAD. I suggest one more improvement:

When an exception occurs in a script (running from autostart) and no-gui was opted for on the command line, QCAD should not try to bring up the debugger ever (regardless of any preferences), but print the message of the exception and possibly a backtrace instead.

Otherwise all errors will produce the same message…

SvgExporter.js uses PrintPreview to parse the scale string, and therefore depends on the qt GUI part. That should not make maintenance harder to call RMath directly there? Results seem to match from a first look.

--- SvgExporter.js~	2011-10-20 14:11:45.527589416 +0200
+++ SvgExporter.js	2011-10-20 14:12:46.277502814 +0200
@@ -1,6 +1,5 @@
 include("scripts/library.js");
 include("scripts/date.js");
-include("scripts/File/PrintPreview/Print.js");
 
 /**
  * File exporter implementation for the SVG format.
@@ -116,7 +115,7 @@
     this.svgUnitAbbr = ret[1];
 
     // scale
-    this.scale = Print.parseScale(this.scaleStr);
+    this.scale = RMath.parseScale(this.scaleStr);
 
     var bb = this.doc.getBoundingBox();
     var size = bb.getSize();

In RC1 text in PG SVG will be in the wrong location. The position passed from native code to the SvgExporterPG.prototype.exportEntity is wrong:

Instead of the actual place of the text it gets the position of the surrounding block entity, or, for text that is not in a block, “0,0,0”.

Dimension labels are not affected by this. Also HAlign and VAlign are not passed correctly for text in the model-view block.

RC1 is lazy in saving appearance to config. I noticed, because it always started with default window size. Maximizing was not carried over, also the panels were consistently reset.

Only when eg. dragging the handle to change cad-toolbar width not from preferences it would write an “appearance” section to the config file.

The appearance section should be written rather sooner than later.

Multiline text is in the wrong place. Please see patch below:

— SvgExporterPG.js~ 2011-11-04 22:08:57.000000000 +0100
+++ SvgExporterPG.js 2011-12-07 13:01:43.811533803 +0100
@@ -248,7 +248,8 @@

   this.writeStartElement("flowRoot"); // <flowRoot>
   this.writeFontAttributes();
   var bb = this.text.getBoundingBox();

- var pos = this.text.getPosition();
+ var pos = this.text.getPosition(); always (0,0) ?
+ var pos = bb.getCenter(); // still not right, but closer

   var x = this.convert(pos.x);
   var y = this.convert(pos.y);
   var a = 360 - RMath.rad2deg(this.text.getAngle());

Put the asterisk in tab title of modified files in front of the name, so it can be seen, when there are so many tabs, that the names will be truncated.

Draw a horizontal dimension. Stretch (S S) it. The label remains in place. It should instead go to the new center. (Unless it was manually positioned perhaps...)

Workaround: Pick one extension and drop it to where it was, label gets centered.