These methods provide a common way to draw HTML text above a canvas.
The getTextInfo method generates div HTML for text with a given font
style/class and angle, measures the element's dimensions, and saves
everything in a cache. The drawText method takes the resulting entry,
finishes generating the inline styles necessary to position the div, and
adds the result to a buffer. The render method dumps the buffer into an
overlay and expires unused cache entries.
Moved canvas creation and size management into a new Canvas class.
This is the first step towards a more object-oriented architecture.
Since we create multiple canvases, and have to maintain several
module-global variables to track their properties, they are the ideal
place to start.
This commit also removes sizing code that was duplicated between
makeCanvas and resizeCanvas.
Due to limitations in our plugin architecture, the categories plugin
duplicates code from Flot's core for adding a dummy point to snap the y
axis to zero. We can get rid of this duplication in 0.9; for now we'll
just update the duplicate to match the change in core that introduced
the new 'zero' option.
This also includes a tweak to zero's default. Previously zero only
received a value if lines were visible; now it always receives a value,
matching the behavior of other contextual options.
Use bind, rather than .mouseleave, because we officially still support
jQuery 1.2.6, which doesn't define a shortcut for mouseenter or
mouseleave. This was a bug/oversight that was fixed somewhere around
1.3.x. We can return to using .mouseleave when we drop support for
1.2.6.
Rounding errors are introduced when calculating the percentage when the total is 100 (for example if percentages have already been calculated). Calculating (total/100) first eliminates the error in this case.
Added a format option 'autoscale' that controls whether the given point
is considered when determining an automatic scale.
The lines & bars 'zero' option controls whether autoscale is set on the
dummy point that is inserted to create the series lower-bound.
Area and bar plots normally use a minimum of zero, since their purpose
is to show size, and using an auto-scaled minimum distorts the plot's
meaning. But this behavior is undesirable in cases where the plot type
is used in more of a decorative sense.
The zero option provides a way to control this behavior. It defauls to
true for bars and filled lines.
When the placeholder has (or inherits) the HTML 'dir' attribute or CSS
'direction' we get unexpected results from text metrics, resulting in
visual glitches on the axes.
The suggested solution in #716 was to set ltr on the placeholder, but
this introduces its own problems, since the user probably *does* expect
rtl on items like the legend. So we'll instead set ltr only on the
canvases.
We should review this behavior at some point; rtl is something we need
to handle, not work around. It also needs to be kept in mind as we move
canvas-text into a plugin. But for now this solution at least ensures
consistent behavior.
When a pie's labels don't fit within its container, the pie is redrawn
with a smaller radius until the labels fit, or a fixed number of retry
attempts are exhausted. The redraw flag was not reset on success,
however, which prevented the pie from being redrawn again after a resize
or update.
The primary canvas uses position: absolute while the overlay canvas does
not. This can cause the two to get out of alignment in rare cases when
floating elements are placed near the plot placeholder. There doesn't
appear to be any reason why the overlay can't also be
absolutely-positioned, so I've just removed the flag entirely.
David Schnur
hizhengfu
Daniel Shapiro
Ivan Novikov
James Ward
Anthony Ryan
Mark Côté