Doesn't use them in libc headers so that those don't have to pull in
AK/Platform.h.
AK_COMPILER_GCC is set _only_ for gcc, not for clang too. (__GNUC__ is
defined in clang builds as well.) Using AK_COMPILER_GCC simplifies
things some.
AK_COMPILER_CLANG isn't as much of a win, other than that it's
consistent with AK_COMPILER_GCC.
This adds simple dotted lines (horizontal/vertical only for now).
There's a little number fudging added in to make sure the final
dot is always drawn at the endpoint (for lines with at least a
handful of dots).
It's a common pattern on the web to draw a circle/ellipse by setting
the border-radius to 50%. Previously the painter would do a lot of
extra work painting and clipping each corner, this now detects that
case and replaces it with a single call to fill_ellipse().
The issue mentioned in the previous FIXME also applied to circles,
I just had not noticed. This is still not a prefect fix rather it
just papers over it, but it now seems to render circles correctly.
This is a first pass at antialiased outline ellipses, currently
this is done by painting two filled AA ellipses, and then
subtracting the inner ellipse from the outer.
This produces a good result, but unfortunately requires allocating
a temporary bitmap in the painter. I did try a simpler method
using the existing line painting functions, and drawing the
ellipse as many line segments, but that produced very poor results.
I think with some work it should be possible to remove the extra
allocation, and I've left a big FIXME for this, but I could not
get this working well.
This commit adds draw_ellipse() and moves the shared code
for circles and ellipses to draw_ellipse_part().
draw_ellipse_part() can draw an entire circle in one call using
8-way symmetry and an ellipse in two calls using 4-way symmetry.
Previously we transformed each rasterized point when drawing a line.
Now we transform the lines' endpoints instead.
That means running two transforms per line instead of transforms for
each pixel. It is not clear that the overhead for the fast path is
still worth it. If we still want to optimize identity and translations,
it is probably better to do that inside AffineTransform.
In addition this will behave nicer if the transform includes scaling.
Previously this would rasterize lines before scaling. Which means
drawing too many points when scaling down, and not drawing enough
points when scaling up.
With the new approach we will automatically rasterize at pixel scale.
This is essentially the same as OpenGL, where vertices are transformed
and rasterization happens in screen space.
Instead of taking a callback that performs the coordinate transformation
we now just take a bool template parameter.
Thanks to Idan for suggesting this! :^)
If the effective 2D transform is just a basic translation, we now simply
translate the underlying painter before & after drawing AA lines.
This avoids all the extra math that otherwise has to happen when mapping
points through an affine transform.
This noticeably increase "mousing around" performance on Wikipedia. :^)
