kicad-developers team mailing list archive

[Dick Hollenbeck <dick@...>]

Vesa Solonen wrote:
> I made some very simple tests for antialiasing graphics on wxGTK. Mostly
> I experimented with wxpython demo package to get a grip how stuff is
> done. Attached is two line patch and results with wxGCDC wrapper. It
> seems there is quite a work to do for proper future proof graphics
> update. Currently there is no caching so it takes a long time to draw
> all primitives and for high quality, drawing needs to be ported to some
> path based api. From the screenshot it can be clearly seen that every
> path style primitives (circles, boxes) draw nicely, but (font)
> connections get messed because of rounding errors or something. Redraw
> is not implemented, so to get antialiased display minimize–maximize
> cycle or 'painting' with other window has to be done. Also dot grid is
> messed like fonts.
>
> Some links I used for inspiration:
>
> http://chandlerproject.org/bin/view/Projects/WxPythonGraphicsContext
> http://docs.wxwidgets.org/trunk/classwx_graphics_context.html
> http://wxforum.shadonet.com/viewtopic.php?t=17122
> http://repo.or.cz/w/geda-gaf/pcjc2.git
>
> The last one as an example of what caching gives and
> http://www.cairographics.org/ capabilities demo, which is used on wxGTK.
> Bug http://trac.wxwidgets.org/ticket/4187 almost got me – I saw what was
> going on, but didn't know why.
>
> -Vesa

I am excited about wxGraphicsContext class. I am not excited about the 
wxGCDC class. I am not sure I understand the thinking behind wxGCDC. 
It only exposes the wxDC API, which is not as rich as the 
wxGraphicsContext API.

Without using wxGCDC, at any point in newly written code, a call can be 
made to

wxGraphicsContext* Create(const wxWindowDC& dc)

as part of the window's drawing function.

Then the returned wxGraphicsContext* can be used to draw into the 
wxWindow correct?

The path support brings irregular border capability to filled areas and 
is a richer base to build on. However, it relies on "double" not 
"int" parameters.

I am not excited about the patch. I would get excited about using the 
wxGraphicsContext class after the February release.

It is not clear to me why the refresh is not working. But this is a 
major new study that could probably be put off until after the release.

Just my 2 cents.

Dick


*wxGraphicsContext <cid:part1.01020601.08050000@...>** 
*Create*(*const wxWindowDC <cid:part2.04090502.04020009@...>& */dc/)